NIST

PUBLICATIONS

NBSIR 78-887

DEVELOPMENT AND EVALUATION OF

AN LNG SAMPLING MEASUREMENT SYSTEM

W. R. Parrish

J. M. Arvidson

J. F. LaBrecque

Thermophysical Properfteb Divibiun

National Engineering Laboratory

National Bureau of Standards

Boulder, Colorado 80303

July 1978

Prepared for: LNG Sampling Measurement Supervisory Committee

*QC —

100

.U56

*78-887

NBSIR 78-887

DEVELOPMENT AND EVALUATION OF

AN LNG SAMPLING MEASUREMENT SYSTEM

W. R. Parrish

J. M. Arvidson

J. F. LaBrecque

Thermophysical Properties Division

National Engineering Laboratory

National Bureau of Standards

Boulder, Colorado 80303

July 1978

Prepared for:

LNG Sampling Measurement Supervisory Committee

U.S. DEPARTMENT OF COMMERCE, Juanita M. Kreps, Secretary

Sidney Harman, Under Secretary

Jordan J. Baruch, Assistant Secretary for Science and Technology

NATIONAL BUREAU OF STANDARDS, Ernest Ambler, Director

Rational Bursal of Stanfe-Js APR 17 1979

CONTENTS

Page

1.0 SUMMARY

.

1 2.0 INTRODUCTION 2 2.1. Scope of Project 2 2.1.1. Gas Analysis 2 2.1.2. LNG Sampling 3 2.2. Method of Evaluation 4

3 . 0 PREVIOUS WORK 7 3.1. Gas Analysis 7 3.2. LNG Sampling 7 4.0 GAS ANALYSIS 13

4.1. Comparison Between Gas Chromatograph and Mass Spectrometry . . 13

4.1.1. Gas Chromatograph System 13

4.1.2. Mass Spectrometer System 18

4.1.3. Evaluation of Results 19

4.2. Statistical Evaluation of GC Analyses 21

4.3. Evaluation of Gas Chromatograph Column Configuration and

Digital Integrators 23

4.3.1. Selection of Column Configurations and Column

Packings 26

4.3.2. Digital Integrator Evaluation 35

4.4. Determination of the Effect of Operating Variables on Gas

Chromatograph Analysis Accuracy and Precision 35

4.5. Sample Handling Procedures 38

4.5.1. Test Apparatus and Procedure 38

4.5.2. Evaluation of Results 40

4.6. Conclusions and Recommendations 4 0 4.6.1. Accuracy and Precision of Analysis by Gas

Chromatography 4 0 4.6.2. Sample Handling 4 2 4.6.3. Recommended Criteria for Selecting a Gas Chromatograph-Integrator System 42

4.6.4. Recommendations for Future Work 4 3 5.0 LNG SAMPLING 4 3 5.1. Laboratory Tests 44

5.1.1. Laboratory Facility ' 44

5.1.2. Experimental Procedure 48

5.1.3. Experimental Results 51

5.2. Confirmation Tests 94

5.2.1. NBS LNG Flow Facility Test 1 94

5.2.2. Shipboard Tests 99

5.2.3. LNG Flow Facility Test 2 106

5.3. Conclusions and Recommendations 125

5.3.1. Recommended LNG Sampling System Design and

Operating Criteria 128

5.3.2. Recommendations for Future Work 128

6.0 REFERENCES 130

APPENDIX 7.1. Gas Analysis Data 132

APPENDIX 7.2. Recommended Criteria for Selecting a Gas Chromatograph for Use in Analyzing Vaporized LNG Samples .... 149

APPENDIX 7.3. Method for Computing the Uncertainty of a Gas

Analysis and a Method for Rejecting a Given Analysis . . 150

APPENDIX 7.4. Sampling Data 154

8.0 ACKNOWLEDGMENTS 196

iii

DEVELOPMENT AND EVALUATION OF AN LNG SAMPLING MEASUREMENT SYSTEM

W. R. Parrish, J. M. Arvidson and J. F. LaBrecque

This report describes the development and evaluation of procedures and

components for sampling and analyzing LNG from flowing streams. Laboratory

and field test results showed the total uncertainty in the computed heating

value of samples taken with the recommended sampling system could be routinely within + 0.3 percent; this included the + 0.1 percent uncertainty in

analysis by gas chromatography. Three sample probes and two vaporizer designs were considered. Of the ten operating variables considered, six were

found to be important in sampling. Test results were used to establish

recommended design and operating criteria.

Key words: Custody transfer; density; gas analysis; gas chromatography;

heating value; hydrocarbon; liquefied natural gas; phase equilibrium; pipelines; sampling.

1 . 0 SUMMARY

Accurate determination of the total dollar value of LNG shipments re- quires knowing the cargo heating value; this is computed from the composition. At current LNG prices, a composition error of one percent in the

3 heating value would cause an inequity of roughly $65,000 for one 125,000 m

LNG shipment. Accurate LNG composition determination requires:

a) a sample probe for drawing a sample representative of the fluid

passing the sampling point,

b) a sample conditioner for completely vaporizing the sample,

c) a gas analyzer for accurately and precisely analyzing the sample

composition, and

d) a correct set of operating parameters and procedures.

This report describes the results of a systematic study evaluating all

of the above components. The work was confined to the problem of sampling

from a flowing LNG stream.

Instead of directly measuring the heating value by gas calorimetry, the

gas composition was analyzed so that both heating value and liquid density

could be computed.

For analyzing vaporized LNG samples, gas chromatography was selected

over mass spectrometry because it was found to be more precise and accurate.

By using a gas chromatograph-programmable integrator system, the total un- certainty in the heating value (on a unit volume basis) , as computed from

the analyzed composition, routinely can be less than + 0.1 percent. This

figure includes a + 0.03 percent uncertainty in the calibration gas composition; this uncertainty, which neglects the uncertainty of the individual

components heating value, is based only on the uncertainty in the weighing

process used to prepare the mixtures. The +0.1 percent uncertainty also includes a random error of + 0.06 percent. The random error is three times the

estimated standard deviation of + 0.02 percent. This value represents the

maximum value obtained from over 100 measurements of three or more repetitive

analyses employing a properly operating gas chromatograph-programmable integrator
system. This report recommends procedures and equipment for analyzing vaporized LNG samples.

Based on the results of sampling tests at the NBS LNG Flow Facility, the

total uncertainty of a single measurement in sampling and analyzing LNG mixtures

can be less than +0.3 percent in the computed heating value. This uncertainty

includes the + 0.03 percent uncertainty in the calibration gas composition plus an uncertainty of + 0.27 percent for random error. The +0.27 percent figure

represents three times the upper limit of the standard deviation determined

for the combined sampling plus analysis measurement process. The recommended

sampling system consists of a side tap probe, a steam or electrically heated

tube vaporizer, a gas mixing chamber and a sampling manifold. This report

gives recommended sampling system design criteria. Also, it lists the recom- mended ranges of the operating variables found to affect sampling precision.

Data obtained during a shipboard test has limits of precision of + 0.30%.

See section 5.2.2. These limits compare very favorably to the + 0.27% obtained on the flow facility.

2 . 0 INTRODUCTION

Composition plays an important role in determining the total dollar

value of LNG shipments. Sampling LNG presents special problems because of

possible fractionation during the sampling process. Accurate and precise

composition determination of LNG mixtures (and other cryogenic liquid mixtures) requires a Sampling-Measurement System (SMS) which contains:

a) a sampling probe which draws a sample without altering the composition,

b) a sample conditioner which completely vaporizes the sample, and

c) a gas analyzer which accurately and precisely analyzes the sample.

Also, the SMS may include facilities for collecting representative samples of

vaporized LNG for transport from the sampling point to the analytical laboratory. The proper operating parameters and procedures must be specified to

minimize the total uncertainty in the measurement process.

2.1. Scope of Project

The project consisted of two primary tasks:

a) the evaluation of vaporized LNG analysis methods, and

b) the evaluation of LNG sampling techniques. This project carefully

evaluated possible alternatives for each of the components of the SMS.

Because of the time limitations only the most promising alternatives were

considered in depth. The study covered only sampling from flowing LNG streams.

Emphasis was on compositions typical of Algerian LNG (see table 2.1).

2.1.1. Gas Analysis

The initial phase of work evaluated the relative merits of analyzing

vaporized LNG samples by gas chromatography (GC) and mass spectrometry (MS)

;

accuracy, precision and simplicity were the primary factors considered. The

2
Table 2.1. The anticipated composition range of Algerian LNG.

The values in parentheses denote the ranges covered in this report.

Component Composition Range, mol % Nitrogen

Methane

Ethane

Propane

iso Butane

normal Butane

Pentanes and heavier

0.60 to 1.40 (0 to 11)

84 to 92 (65 to 90)

6 to 9.5 (5 to 18)

2.2 to 3.5 (1.0 to 5.4)

0.3 to 0.5 (0 to 0.8)

0.3 to 0.7 (0.2 to 4.8)

0 to 0.02 (0 to 0.3)

second phase of work was a study of the effect of various parameters on the

accuracy and* precision of analysis by GC; the work included an evaluation of

GC columns and GC data processors (i.e., integrators). Gas mixtures prepared

by weight were used in all of these tests. Also, reliable procedures for obtaining a representative gas sample in a sample cylinder were identified.

2.1.2. LNG Sampling

The sampling portion of the project contained laboratory tests and field

confirmation tests; these tests were performed at the NBS LNG Flow Facility

and aboard the LNG tanker El Paso Consolidated . The laboratory tests evaluated three probes — a pitot tube, a side tap

and a reference probe - and two continuous vaporizers - vaporizer A and a reference vaporizer. To distinguish effects due to the vaporizer from those

of the probes, the probes were used with a reference vaporizer and vaporizer

A with the reference probe. The laboratory evaluation provided a rapid way

to determine the effect of a given operating variable while holding other

variables constant. The variable's effect upon sampling accuracy was determined by using mixtures of known composition. In addition to the three

probes and two vaporizers we considered the following operating variables:

a) flow rate of the liquid stream,

b) flow rate through the sampling device,

c) amount of subcooling (pressure differential between the sample

point and the saturated liquid)

d) temperature of the LNG,

e) pressure drop upstream of the sample vaporizer,

f) time-averaging the sample,

g) vaporizer outlet temperature, and

h) composition, particularly the effect of pentane and higher hydrocarbons.

The field confirmation tests provided a scale-up test for the conclusions obtained from the laboratory tests. Two series of tests were made in

3
the NBS flow facility. Here, operating conditions were closer to the con- ditions of actual LNG facilities in respect to size, pressures and flow

rates. However, there was no way to directly determine the correct composition of the mixture in the flow facility. Also, operating conditions were

not as constant and well defined as in the laboratory apparatus.

The shipboard tests provided an evaluation of a LNG sampling system

under conditions comparable to those in LNG custody transfer operations. The

primary variable evaluated in these tests was sampling rate. The actual LNG

composition was unknown. However, comparisons were made between liquid

samples taken from the inlet header to the ship's vaporizer and gas samples

taken from the vaporizer outlet header. This provided a check on the liquid

sampler performance.

2.2. Method of Evaluation

In LNG custody transfer, the composition is important because it is

needed to compute the heating value and sometimes liquid density. Therefore,

in this report we compared experimental results using compositions, computed

heating values and computed liquid densities. Several sets [1,2] of ideal

gas heating values are available. We chose the values proposed by the A.G.A.

[1] (see table 2.2) because, with their method of correcting for gas nonidealities, computed heating values could be directly compared with the results

of combustion calorimetry. For convenience, we omitted the non-ideality

correction in most of the work. However, in the LNG flow facility tests, the

nonideality correction was necessary to make direct comparison with calorimeter measurements. Methods for computing the liquid density are currently

under study [3]. For the laboratory tests, we chose the semi-empirical

method of Hiza [4] because of its relative simplicity; the extended corresponding states method [3] was used in the field tests.

Table 2.2. Pure component ideal gas heating values [1]

Component Heating Value"*"

Btu/scf MJ/m3

N

2 0 0 CH

4 1012.1 37.701

C

2 H

6 1773.0 66.045

C

3 H8 2523.

93.994

iC

4 H10 3260. 7 121.46

nC

4 H10 3269.

121. 80

iC

5 H12 4008.

149. 33

nC

5 H 12 4018.

149.71

C"6 H14' average 4764.4 177.48

C"7 H 16' average 5509.205.34

The ideal gas volumetric heating value is based on the standard conditions of

60°F (15.6°C) and 30 inches of mercury (0.1016 MPa)

4
This report makes extensive use of statistical techniques in evaluating

the experimental data. Table 2.3 lists the definitions of the statistical

terms used.

Table 2.3. Definition of statistical terms used in this report.

Accuracy - the closeness to the true value.

Average value (x) - the arithmetic average of replicate measurements. The

average value represents the most likely value of the mean. Bias (B) - a systematic offset between the mean and true value.

Estimated standard deviation (s) - an estimate, based on a finite number of

replicate measurements, of the standard deviation of a measurement

process

Mean (X) - a value, usually unknown, about which the measured values of

replicate measurements randomly scatter.

Measurement process - a series of steps used to assign a numerical value to

a physical property.

Random error - an error related only to the random behavior within a measurement process, i.e., not a systematic offset.

Replicate measurements - two or more measurements made under conditions where

all controllable variables are identical for all measurements.

Standard deviation (a) - a parameter often used as a measure of the scatter

of random error in a measurement process.

Systematic error - an estimate of the upper limit of the unknown but fixed errors of a measurement process.

Total uncertainty - the estimated maximum error in a measurement process.

In this report it is computed by summing the systematic error and

the upper limit of the random error — taken to be three times the

estimated standard deviation.

Confidence interval - an interval, based on replicate measurements, for a parameter which will include the true value of the parameter a specified percentage of the time.

Precision - the closeness with which the results of replicate measurements

agree -- usually quantified by the estimated standard deviation.

Determining the composition, like all measurement processes, involves

experimental error. This error may be considered in terms of the accuracy of

a process (bias) and its precision. Bias of a measurement process represents

how closely the mean of the measured quantity conforms to the true value. Precision represents how closely the values obtained from a number of independent,

repeated measurements agree, i.e., random error. Replicate measurements yield estimates of both bias and precision. The

difference between the average value, x, of the measured values, x^, and the

true value is an estimate of the bias in the measurement process. Scatter

about the average value is an estimate of the precision; normally the scatter

is quantitated in terms of the estimated standard deviation, s. In this re- port we assume that the random errors follow the statistics of a normal distribution. The estimated standard deviation is given by

5
s (x

i -x) 2 /(n-l) (2.1)

where n denotes the number of replicate measurements.

The values of x and s will vary among different sets of the same measurement. However, they will vary about the true mean, X, and standard

deviation a. The values of X and a are considered known only after making a very large number of measurements. The values of X and a are estimated by

using x, s and confidence intervals; for example, a 99 percent confidence

interval for the mean value signifies that 99 percent of the time the interval

will include the true value. In this case the interval is given by

where t is the Student's statistic for a 99 percent confidence of n repeated

measurements

For the standard deviation, the confidence interval is given by

where B and B are values derived from the Chi Squared statistic; they are

Li U functions of s, n and the degree of confidence (e.g., 99 percent). The

interval in equation (2.3) is unsymetrical about a. In this report we present values of n, x and s and, as a first approximation assume that x and s are equal to X and a. We use the concept of total uncertainty in assuming a limit on the error

in a measurement process. Total uncertainty reflects two errors — systematic

and random. The systematic error represents an estimate of the upper limit of

the unknown, nonrandom errors of the measurement process. Its estimate is based

on understanding the nonrandom errors of the components within the measurement

process. The random error is estimated to be three times the estimated standard

deviation - this roughly corresponds to a 99.7 percent confidence interval (it

would equal a 99.7 percent confidence interval if the estimated standard deviation equaled the standard deviation)

One of the major goals of this project was to determine which operating

variables affected the precision of composition measurement. To determine if

a given variable changed the precision, measurements would be made at two (or

more) values of the variable. How confidently we could detect the change in

precision depended upon the number of samples taken under each set of conditions and upon the observed change in the estimated standard deviation. As shown

in table 2.4, we have a 65 percent chance of detecting a difference in the precision when there is a factor of four difference between the observed standard

deviation and when the measurement is repeated four times with each value of the

operating variable; for a 62 percent chance of detecting a difference when there

is a factor of two difference in the observed standard deviation it would take

10 measurements with each value of the operating variable.

x - t«s//n < X < x + fs//n (2.2)

B_ • s < a < B. • s (2.3)

6
Table 2.4. Probability of detecting a difference in the standard deviation

between two sets of conditions (A and B) when the measurements have a factor

X difference in standard deviations and they are repeated N times under

each set of conditions [5]

N

Probability, percent

A (= a B/aA

)

1 2 3 4

4 5 25 49 65

6 5 41 71 87

8 5 52 87 95

10 5 62 93 99

3.0 PREVIOUS WORK

To our knowledge no systematic evaluation of LNG Sampling Measurement

Systems (SMS) has been made. However, there are publications on gas analysis

methods and on LNG sampling techniques.

3.1. Gas Analysis

We are unaware of any publications comparing gas chromatographic (GC)

and mass spectrometric (MS) analyses of natural gas. However, ASTM standards

exist for natural gas analysis by gas chromatography [6] and mass spectrometry [7] . Each standard gives the estimated reproducibility of analysis;

values are given for the case of one laboratory and apparatus, and for the case of different laboratories. The ASTM standards indicate that the analyses should be considered suspect if differences between replicate analyses

are greater than those given in table 3.1; also, the table gives the estimated error in heating values for these differences assuming the composition

range given in table 2.1.

There are several papers discussing different GC column configurations;

these are discussed in section 4.

3.2. LNG Sampling

Dalmaze [8] and Trigo [9] discussed two similar continuous SMS which are used in Europe. Figure 3.1 is a schematic of Dalmaze' s system. Both use an upstream facing pitot tube located at the LNG pipe centerline as the probe.

To prevent premature vaporization the probe line is cooled by an outer jacket

through which LNG is circulated and returned to the main line. The sample

then flows through a check valve to prevent backflashing and past an electrically heated vaporizer. Trigo 's system replaces the check valve with a filter. The vaporized sample goes through a vessel to dampen pressure

pulsations (if operating at less than 30 psig (0.3 MPa) ) , past a pressure

controller, and to a chromatograph. Neither author describes the details of

the gas analysis. Dalmaze' s data showed a precision of + 0.6 percent in the

computed heating value of liquid samples taken upstream of a LNG vaporizer;

7
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9
by sampling the totally vaporized LNG stream the precision was 0.4 percent.

(The precision is defined here as three times the estimated standard deviation.) The difference in the average computed heating values between the two

sampling methods is about 0.01 percent when 30 sets of samples were averaged

over seven hours. Dalmaze reports that this difference is well within the

error due to gas analysis alone.

There are at least two batch sampling devices which have been tried. One

is the cryogenic sampler [10] shown in figure 3.2. LNG passes through a cooling passage which surrounds a cup contained in an evacuated outer container. Once the cup is at LNG temperature the sample valve is opened and the

cup is filled with liquid. After the cup is full the sample valve is closed,

the sample lines are disconnected and the sampler is allowed to warm to ambient

temperature. The ratio of the cup volume to the total chamber volume is such

that the final pressure will be approximately 500 psig (3.6 MPa) for LNG. A

valve at the bottom of the sampler is used to draw a gas sample for analysis.

The other batch sampling device which collects the liquid is described by

Cook [11] and is shown in figure 3.3. To take a sample, both valves are opened to allow LNG to flow through the sampler which is well insulated. Once

the sampler is at LNG temperature, as evidenced by a continuous liquid flow

from the device, both valves are closed. Then the device is removed from the

sampling line and allowed to warm up. After the initial pressure rise, a pressure relief valve which is set above the cricondenbar (the maximum pressure at which a mixture may exist in two phases) of the mixture (> 2000 psi

(13.8 MPa)) keeps the sample at a constant pressure and in one phase. Once

the sampler is warm it can be connected directly to an analytical instrument.

Methods for collecting a gas sample from a pipeline have been discussed

by Miller [12]; also, an ASTM standard exists for natural gas sampling from

pipelines [13] . Miller concludes that all of the following filling methods

give good results:

a) liquid displacement,

b) purge by fill and empty,

c) purge at a constant flow rate, and

d) fill of evacuated cylinder with no purge. Also, he briefly describes

the two batch sampling devices used for collecting LNG as a liquid which were

described above.

Finally, Chapman and Payne [14] give some general guidelines for sampling

flowing streams. Although they do not describe cryogenic sampling systems,

many of their guidelines still apply.

10
11
12
4.0 GAS ANALYSIS

Before any sampling data could be taken we had to determine the uncertainty involved in gas analysis. This evaluation and a comparison between

gas chromatography (GC) and mass spectrometry (MS) were made early in the

project. Later, we more carefully evaluated the effect of various operating variables, column configurations, and digital integrators on analysis

precision and accuracy. Appendix 7.1 lists all of the data obtained for

the gas analysis tests.

4.1. Comparison Between Gas Chromatography and Mass Spectrometry

A comparison of precision and accuracy of GC and mass spectrometric

analysis of LNG type mixtures was made by having a local MS laboratory

analyze some prepared mixtures; these mixtures also were analyzed using a GC in our laboratory. The MS laboratory was capable of general quantitative analysis, including hydrocarbon analyses, on a routine basis.

4.1.1. Gas Chromatograph System

4.1.1.1. Apparatus

In this phase of the work we used a gas chromatograph containing two

columns and a filament-type thermal conductivity detector, in conjunction

with a programmable, digital integrator (integrator A) . Traditionally, whenever feasible, peak heights were preferred over peak areas for computing com- positions from GC analyses. The reasons for this were that peak heights were

easier to measure and they were oftentimes more precise than the mechanical

devices available for measuring peak areas. However, programmable integrators

eliminate the drawbacks of using peak areas. Several sets of calibrations

and analyses were made using both peak heights and peak areas. (Integrator

A reports peak areas and/or peak heights.) These tests showed that the com- positions based on peak heights had an estimated standard deviation which

was four to five times greater than the estimated standard deviations for the

the compositions computed from peak areas. Based on these results and the

fact that the linear response between peak height and composition has a limited range, we used peak areas throughout this work.

Table 4.1 lists the GC operating conditions. Figure 4.1 is a schematic

of the GC and ancillary equipment while figure 4.2 shows a chromatogram (on

a logarithmic scale) for a gas mixture typical of Algerian LNG. The GC

contained a sample valve which was used to inject the gas sample from

either of two sample loops into the carrier gas stream. Helium carrier gas was maintained at a constant flow by using two stages of pressure regulation. The column bypass valve was used to bypass Column 2. In the bypass

mode the carrier gas passed through a needle valve set to have the same pressure drop as Column 2; this minimized the baseline upset during valve

switching.

13
Table 4.1. Gas chromatograph operating conditions.

Carrier gas flow rate 27 cc/min (at 14 . 7 psia (0.1 MPa)

Sample loop volumes ^ 0.1 cm

3 each

Sample loop temperature 90°C

Column 1 temperature

(10 ft (3.0 m) x l/£

25°C

i in (3.2 mm) of Durapak*, 60/80 mesh)

Column 2 temperature

(6 ft (1.8 m) x 1/8

25°C

in (3.2 mm) of PoraDak 0. 60/80 mesh

Detector temperature 120°C

Filament current 220 ma

* Certain commercial equipment, instruments, or materials are identified in

this paper in order to adequately specify the experimental procedure. In no case does such identification imply recommendation or endorsement by the

National Bureau of Standards, nor does it imply that the material or equipment identified is necessarily the best available for the purpose.

The integrator had a variety of operating parameters and timed events

which could be used to maximize the precision of the data reduction of a chromatogram. The use of these parameters is illustrated in the next section.

4.1.1.2. Calibration procedure

All GC ' s require calibration with one or more mixtures of known composition; these mixtures should have a composition similar to that of the

unknown mixtures. In this work we prepared all of the calibration mixtures

by weight using high purity components; table 4.2 lists the component con- centrations and their estimated uncertainties for all the prepared mixtures

used here.

To make a calibration run, the sample loop first was purged by alternately evacuating and filling with the calibration gas. We found that one to

three purges were adequate provided that the manifolding was arranged so that

all of the gas passed through the sample loop during purging (see figure

4.1). However, it was imperative that all connections were leak-tight.

After purging, the sample loop was filled to the desired pressure — in our

case 2 psig (0.11 MPa) — and the sample valve was switched, injecting the

mixture into the carrier gas stream. During the first three minutes of the run Column 2 remained in series; this allowed the nitrogen and methane to

travel through both columns and the detector. (These columns did not resolve

oxygen and nitrogen; therefore, any oxygen present was included in the nitrogen peak.) Once the methane was out of Column 2, the column was bypassed,

trapping the ethane. The integrator made a "forced baseline" just prior to

the valve switch and ignored the tailing baseline after the switch. (The

dotted lines under each peak in figure 4.2 represent the baseline as determined by the integrator.) The integrator then picked the bottom of the baseline drift as the baseline for the propane peak. Column 2 remained bypassed

until the butanes passed through Column 1. At 9 minutes Column 2 was switched in again, allowing ethane to elute from the column. As before, the integrator

14
15
Component

C

2

H

6 nC4

H 10

iC

4

H 10

C

3

H 8

CH

4 Time, min. 12.74 7.94 6.72 3.63 2.44

Area, Arib. units 70890 8643 6142 30721 480864

Peak Height, mV 2.846 0.542 0.461 4.095 82.784

Concentration, mol% 5.477 0.707 0.519 2.980 85.936

TIME, mm

Figure 4.2. A chroma to gram of a natural gas mixture. The peak

heights are shown on a logarithmic scale.

16
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17
ignored the baseline upset due to valve switching. The tailing after switching valves was caused by a temporary decrease in carrier gas flow as pressure

gradients in the line were being reestablished. The two peaks on the second

tail were caused by minute air leakage during the valve switch. This leakage

is caused by diffusion and can occur in pressurized helium and hydrogen

systems

The total analysis time was 14.5 minutes. If pentanes were present the same procedure was used but the analysis time increased to 24 minutes. The

prepared mixtures in this study did not contain hexanes.

Using the areas under each peak and the known composition of the calibration gas, relative response factors were computed for each component.

Normally, two or three calibration runs were made and the response factors

averaged for each component. The GC was calibrated at the beginning of each

operating day.

4.1.1.3. Analysis procedure

The procedure for an analysis of an unknown mixture was the same as a calibration run. However, in this case the relative response factors were

used with the peak areas to determine the composition. In our work we nor- malized the results; this eliminated the need to know the exact amount of

sample injected. However, we tried to keep the sample amount, i.e., sample

pressure, constant to within + 5% because variations in sample size may cause

subtle effects which could diminish the analytical accuracy (see section

4.4) . 4.1.2. Mass Spectrometer System

4.1.2.1. Apparatus

The mass spectrometer used for this work was a 180° sector, high precision gas mass spectrometer [15] . It electronically scanned a mass range of

two to 200 with the output recorded on a strip chart. By adjusting the

sample pressure the pressure at the controlled leak could be set between 1 to

100 microns (0.1 to 13 Pa). Tne controlled leak permitted a small amount of

sample to continuously enter the ion chamber; the leak rate was proportional

to the pressure upstream of the controlled leak.

4.1.2.2. Calibration procedure

Prior to running a calibration (or analysis) , a background scan was made

by closing the valve upstream of the controlled leak. Any peaks from the

residual gas were noted. Next, high purity hydrocarbons (> 99.99 percent)

were injected, one at a time, at pressures comparable to the expected partial

pressures in the unknown mixture. The MS response was slightly non linear;

however, this effect was negligible as long as the calibration pressure was within 3 to 4 microns (0.4 to 0.5 Pa) of the components partial pressure in

the unknown mixture.

18
Hydrocarbons fracture inside the ion chamber. Each hydrocarbon has a characteristic cracking pattern and at least one mass peak which is unique

to that hydrocarbon. The response factor was computed for each component by

dividing the characteristic peak height (corrected for background) by the

known calibration gas pressure. (Resolving the iso and normal butane re- quired solving two simultaneous equations.)

4.1.2.3. Analysis procedure

After evacuating the line connecting the sample cylinder to the MS, the

sample pressure was reduced to the desired level by a series of expansions

into evacuated volumes. Then, the sample was opened to the controlled leak

and a mass scan was made. Using response factors, peak heights (corrected

for background) and sample pressure, the composition of each component was calculated

4.1.3. Evaluation of Results

The MS laboratory received two sets of six samples. The first set

contained duplicate samples of mixtures A, B and D, while the second set

contained duplicate samples of mixtures B, C and D; the samples were labeled

with the approximate composition of the sample. The MS lab reported two

analyses on each sample. Table 4.3 gives the results of the MS and GC

analyses. The raw data are listed in Appendix 7.1. Since this was not a statistically balanced test, only a comparison of the bias (i.e., accuracy)

and precision could be made; there was no way to determine what factors

affected the accuracy and precision. However, it was found that the second

set of MS analyses showed a significant improvement in the standard deviation,

whereas, there was little change in the bias. In all cases both biases and

standard deviations for the GC analyses were much smaller than those of the

MS analyses.

The manager of the analytical laboratory where the MS analyses were

made feels that the MS is an important qualatative and quantative tool [15]

However, for routine gas analyses, where all of the components are known, he

believes that a properly designed and operated GC-digital integrator system

will be more precise than the MS. (His laboratory contains several types of

both MS and GC instruments.)

The precision of the MS analysis results obtained in our study is poorer

than would be expected based on the ASTM standard [7] (see table 3.1). One

possible reason is that the reference mixture used in the ASTM standard to

determine analytical precision did not include butanes; butanes and heavier

hydrocarbons made the data reduction of the mass spectrum much more difficult.

Also, the concentration levels of components other than methane were lower in

the ASTM mixture than in our study.

In addition to our comparison we received a tabulation of roughly 30

sets of analyses of natural gas mixtures containing 95 mol percent or more

19
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20
methane. Samples of each gas mixture were analyzed by MS in two different

industrial laboratories and by GC. Also, the heating value of the mixture

was measured by using combustion calorimetry. Table 4.4 lists the average

error and its estimated standard deviation between the computed heating

values, based on gas analysis, and the measured values. Clearly, the GC

analysis is much better than one MS laboratory and has a better estimated

standard deviation than the second MS laboratory.

Table 4.4. The average error and its estimated standard deviation between

the heating values computed from analyses by gas chromatography (GC) , two

different mass spectrometers (MS) and the heating value as measured by com- bustion calorimetry for natural gas mixtures containing 95 mol % or more methane [16]

Analytical

Method

Average Error

Btu/scf

(MJ/m3)

i Standard Deviation

Btu/scf

(MJ/m3)

GC 1.27 0.55

(0. 0473) (0.0205)

MS I 5.05 3.63

(0.1881) (0.1352)

MS II 1.17 1.46

(0.0436) (0. 0544)

The average error is defined here as the average of the absolute value of the

difference between the computed and measured heating values.

4.2. Statistical Evaluation of GC Analyses

Based on the above results the GC was selected to be used in this project.

Therefore, a statistically defined test was required to determine the analytical precision and accuracy of the GC; also, the effect of various operating

parameters needed to be defined. In this test we looked for operator,

composition, and day-to-day effects. We used two operators, four mixtures

(mixtures C, E, F and G, table 4.2) and ran the tests for four days. Figure

4.3 shows the computed ideal gas heating values for mixture E (the calibration gas) as a function of chronological order and operator; the a error

bar represents one estimated standard deviation (0.20 percent) in the heating value. Although there was no operator dependence, there was a day to day

shift in the average value; this probably was due to calibration shifts. Also,

there were apparent changes in the scatter from day to day which could not be

explained; however, excluding the outlier on the last day, the total scatter was 0.09%.

The outlying point on the fourth day illustrates an instrument malfunction discovered in this test. Roughly 20% of the analyses contained one component, usually nitrogen, methane or ethane, whose composition was more

than four estimated standard deviations from the average value. During this

period, the integrator started malfunctioning and had to be returned to the

factory. After receiving the repaired instrument another test was performed,

21
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this time using only one operator and one gas mixture. Figure 4.4 shows

the computed heating values for the 44 analyses which were taken over a two

day period. This time the total spread of computed heating values was 0.07%

and the largest deviation in heating values was 2.8 estimated standard

deviation; 75% of the analyses were within one estimated standard deviation

of the average. This indicated that the malfunctioning integrator had

caused the outliers.

Table 4.5 lists the biases and estimated standard deviations obtained

from the results of the above two tests; values differing from the average

measured value by more than four estimated standard deviations were omitted

in the computations. Comparing the biases of mixture G with those of the

other mixtures points out the necessity of using a calibration gas which is

similar to that of the unknown mixture. Also, the estimated standard deviations were generally larger for mixture G; this indicates that the operating variables would require some modification when analyzing mixtures

containing large amounts of nitrogen and/or ethane.

Figure 4.3 and 4.4 illustrate how an insufficient number of calibration

runs can introduce biases into the computed heating values. Since the calibration gas was the analyzed gas in these figures, the biases had to be

caused by the calibration. In the first test all results were based on a single calibration run at the beginning of the day while two calibrations

were made at the beginning of each day in the second test. We recomputed

the biases for the second test by using the first three runs of each day

for calibration; the bias dropped from 0.009 to 0.005 percent. Thus, it

appears that at least three good (i.e., not a set that includes an outlier)

calibration runs should be used to minimize baises introduced by calibration.

This assumes that the other parameters in the GC system remain constant.

Since this may not always be the case, calibrations should be made several

times during the day as an additional check.

4.3. Evaluation of Gas Chromatograph Column Configuration and Digital Integrators

The previous section determined the precision and accuracy of one gas

chromatograph (GC ) -integrator system. Additional tests employing different

column configurations and integrators were needed to determine the factors

limiting the precision of GC analyses. This section describes tests using

two different three column configurations and two different GC's, and tests directly comparing two different integrators. Table 4.6 summarizes the chromatograph-integrator combinations used in all of the analysis tests.

23
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Table 4.6. Summary of gas chromatograph-integrator systems

used in analysis tests.

Two Column

Configuration

Three Column Conf irugration

Configuration A Configuration B

Chromatograph

Detector

Automatic Valve

Switching

Integrator

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No

A

II

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Yes

A & B

I Hot-wire

No

A

4.3.1. Selection of Column Configurations and Column Packings

Obtaining the most accurate and precise analysis of vaporized LNG

samples requires:

a) resolving oxygen, nitrogen and methane through pentane and column

back flushing (i.e., carrier gas flow reversal) to obtain a composite C,+

D peak,

b) analyzing for all components in a single sample

in j ection

,

c) completing the analysis within approximately 30 minutes,

d) operating the column ovens in an isothermal mode,

f) minimizing the effect of baseline upset by valve switches, and

g) computing the composition by using peak areas. The primary purpose in resolving the nitrogen and oxygen peaks is to

detect contaminated samples since the most likely contaminant is air.

Also, it is a good way to detect leaks in the GC plumbing. The need for

good resolution between the hydrocarbons is obvious. The anticipated con- centration of hexane and heavier components is small (< 0.01 mol percent);

therefore, combining the C^+ fraction into one peak by backflushing causes

an insignificant error in the computed heating value.

The GPA [17] and ASTM [6] analysis procedures suggest using two sample

injections — one injection into a column to resolve air and methane through

pentane followed by a backflush for the C^+ peak; a second injection into a different column to resolve nitrogen, oxygen and methane (the column then is

backflushed to remove the remaining hydrocarbons) . However, the two analyses must be combined. This is done through sample size or methane peak

area. Both methods diminish analytical precision.

The primary reason for minimizing the analysis time is that the peak

height to peak width ratio decreases with increasing residence time. Maximum accuracy and precision in peak area measurement decreases as the ratio

decreases. It was found that, for the column configurations and operating

parameters considered here, the analysis times fell in two ranges — one was

40 minutes or greater and the other was 24 to 30 minutes. Configurations

26
having long analysis times elute the C

g + peak last; the other configurations

elute methane last.

Temperature programming is an attractive way of reducing analysis time

and sharpening peaks of the heavier components. However, whenever feasible,

isothermal column oven operation is normally preferred over temperature programming when using thermal conductivity detectors. This is because flow

variations caused by changing column temperature produce baseline drift when

using these detectors. Temperature programming becomes attractive if the

baseline drift can be compensated for reliably by the integrator or if flame

ionization detectors are used. These detectors are insensitive to flow variations but also do not detect nitrogen, oxygen and carbon dioxide.

Multicolumn configurations require valve switching with its associated

carrier gas flow upsets; these, in turn, produce baseline upsets. The time

duration of baseline upsets are minimized by:

a) adjusting flow restrictors in column bypass lines so that the

steady-state carrier gas flow rate remains constant after switching the column in or out, and

b) using carrier gas inlet pressure instead of mass flow to control

the flow rate [18]

To minimize peak integration problems, each valve switch should occur far

enough away from the nearest peaks to allow baseline establishment between

the peaks and the valve switch.

Traditionally, peak height measurement was preferred over peak area mea- surement for computing composition from chromatograms . Peak height was used

because it was easy, quick and usually more precise than peak area. However,

the peak height response is linear over a narrow concentration range, using

a 0.5 cm"* sample loop volume, peak height response is linear at concentrations below roughly 10 mol percent (peak area response is close to linear

over the entire composition range). Also, peak heights cannot be used with

composite backflush peaks. The currently available programmable integrators

eliminate the drawbacks to using peak areas. Also, since both methane and

Cg+ peaks must be measured, peak area measurement was selected.

Compromises are necessary to meet the requirements listed above. It is

possible to make the complete analysis on one column [19], but it requires

temperature programming between -70°C and 145°C and the Cg+ backflush peak

retention time is about 22 minutes; the C

g + peak width is roughly 3 minutes

which, in combination with the baseline drift caused by temperature programming, can cause errors in the peak area measurement. If the separation of

oxygen and nitrogen is not required, the analysis can be made by temperature

programming between 35 and 145°C. In this case the analysis time is roughly

15 minutes. Based on the data for five replicate natural gas analyses [19]

,

the estimated standard deviation in the computed heating value for this

method is 0.04 percent.

27
The most commonly used column packing for isothermally resolving nitrogen

and oxygen is molecular sieve 5A [18] . It makes a good separation between

nitrogen and methane, but cannot be used with the higher hydrocarbons. This means that at least two columns in series are needed -- one to separate oxygen,

nitrogen and methane (molecular sieve) and one to resolve the higher hydrocarbons (we used DC 200/500 on Chromasorb PAW) . Using this configuration without

temperature programming, the retention time for the pentanes is roughly 20

minutes. After eluting the pentanes, the DC 200/500 column is backf lushed with

the Cg+ peak eluting in another 2 0 minutes; this peak becomes so broad that

at the 0.01 mol percent level it would not be detected using a TC detector

3 and a 0.5 cm sample loop.

When operating the columns isothermally the preferred way to shorten

the pentane and C^-+ retention times is to use two columns to resolve the C^ + hydrocarbons. By selecting the proper column packings, lengths, and temperatures, and by using column bypassing, the components can be eluted in

almost any sequence desired. In this work we considered two three-column

configurations — one which eluted the pentanes and C^+ peaks midway through

the analysis (configuration A) and one which eluted them at the beginning of

the analysis (configuration B)

4.3.1.1. Column configuration A

Figure 4.5 shows a schematic of this three column arrangement and

figure 4.6 is a chromatogram of a sample taken during a flow facility sampling test; table 4.7 lists the operating parameters for this configuration.

The vaporized LNG samples were analyzed using the following automatic valve

switching sequence:

Step 1. Switch valve VI for sample injection -- all columns are in

series

Step 2. Switch valve V2 to bypass columns 2 and 3 after oxygen,

Step 3.

Step 4.

nitrogen and methane have entered these columns; ethane

through pentanes are eluted in this step. (Restrictor A is

adjusted so that its pressure drop is comparable to the pressure drop of columns 2 and 3; this minimizes baseline upset

after valve switchings.

)

Switch valve VI to original position to start backflush.

Switch valve V2 to put columns 2 and 3 back in series with

column 1.

Step 5.

Step 6.

Switch valve V3 to bypass column 3 which now contains oxygen,

nitrogen and methane; ethane (and carbon dioxide, if present) are eluted in this step. (Restrictor B is set to provide

the same pressure drop as column 3.)

Switch valve V2 to bypass column 2; the C^+ peak elutes in

this step.

28
29
30
Step 7. Switch valves V2 and V3 to put column 2 and 3 in series;

oxygen, nitrogen and methane elute in this step.

Table 4.7. Operating conditions for Column Configuration A.

Carrier gas flow rate 3 27.5 scm /min

Sample loop volume 0.5 cm

3

\^ \y J_ H1L LAI _L UCllL^Ci. CL I— U J- G (10 ft. (3 m) x 1/8 in. (3.2 mm) of

15% Squalane on Chromosorb PAW, 60/80 mesh)

Column 2 temperature

(5 ft. (1.5 m) x 1/8 in. (3.2 mm) of

Porapak N, 60/80 mesh)

66°C

Column 3 temperature

5 ft. (1.5 m) x 1/8 in. (3.2 mm) of

Molecular sieve 5A, 60/80 mesh)

66°C

Detector temperature 66°C

Detector current

(Thermistor detector)

Table 4.8 lists the results of a series of analyses made using this

configuration and prepared mixture H (see table 4.2). A comparison of these

results with results given in table 4.4 shows that the precision of the two

different column configurations was comparable. No biases were found in

this test since the same mixture was used for both calibration and analysis;

three calibrations were made prior to running the replicate samples. It is

encouraging that configuration A, with eight valve switches, had about the same precision as the much simpler two column system which had only three valve

switches.

Unfortunately, the backflush peak in configuration A was so broad that

one of the two integrators (integrator A) had difficulties in accurately mea- suring the C,+ peak area at the 0.10 mol percent level (see sections 5.2.3.1).

Although integrator B reliably integrated the C

g + peak, the broad backflush

peak affected the reliability of integrating the following two peaks. It is

extremely unlikely that the integrators would reliably detect a C^+ peak at

the 0.01 mol percent level. (Missing a C

g + concentration of 0.01 mol percent produces a 0.04 percent error in the computed heating value.)

The only way to obtain a relatively precise C^+ analysis is to reduce

the retention time; this can be done by choosing a different three-column

configuration.

4.3.1.2. Column configuration B

If precise determination of pentanes and C^+ concentrations in the 0.01

mol percent range is required, these components must be eluted at the beginning

of the analysis. This is done by using the columns listed in table 4.9 and

the flow scheme shown in figure 4.5. Configuration B uses the following

valve sequence:

31
tnc CD H 3 rH rH •H -P rH 0\0 o O o

-P fO to • • • tO CD > o o o

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tr>

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•P

C

tO o c

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t3

g

g -H ro • . • H CO CJ o o o

+J 0

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(0 CJ

W

g CO 00 r- TJ o o o rH C 0 CJ S3 o o o

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CO

tJl <a o

CD -H o rH CM

-P CO EC o o O

tO 3 CJ . • • g o o o

•h tn

4-> [-> o r~

CO CD o rH o W M rsi o O o 3 > • • -P o o o • X

00 -H • g CO +JC

CD CD CD •H

rH ^ 0 CM CM

XI tO CM rH rH

tO Dj 3

En CDU 0

CUuo 0

MH -P

tO <D3 tj> < PQ rH CD

(0 P > CH1u C 3 c; g tj> 0 3 -H -H <

rH 4H -P 0 C tO U 0U
Step 1. Switch valve VI for sample injection — all columns are in

series

Step 2. Switch valve V2 to bypass columns 2 and 3 after all components

except C,-+ have entered these columns; the iso and normal pentane elute in this step.

Step 3. Switch valve VI back to original position to backflush the

Cg+ component.

Step 4. Switch valve V2 to put columns 2 and 3 into series again.

Step 5. Switch valve V3 to isolate oxygen, nitrogen and methane in

column 3. Ethane through the butanes are eluted in this step.

Step 6. Switch valve V3 to elute oxygen, nitrogen and methane.

Table 4.9. Operating conditions for Column Configuration B.

Carrier gas flow rate 28 scm /min

> Sample loop volume 0.5 cm Column 1 temperature 62 to 68°C

(6 ft. (1.8 m) x 1/8 in. (3.2 mm) of

DC 200/500 on Chromasorb PAW, 60/80 mesh)

Column 2 temperature 60°C

(25 ft. (7.6 m) x 1/8 in. (3.2 mm) of

DC 200/500 on Chromasorb PAW, 60/80 mesh)

Column 3 temperature 65 °C

(6 ft. (1/8 m) x 1/8 in. (3.2 mm) of

Molecular sieve, 5A, 60/80 mesh)

Detector temperature 120°C

Detector current 220 ma

Table 4.8 gives the results of a feasibility test for column configuration B; figure 4.7 is a chromatogram of a mixture containing a C

g + fraction,

The numbers indicate that this configuration produces more scatter than

configuration A. However, these results are inconclusive because during

these tests:

a) there were temperature fluctuations in the column 1 oven (this

oven was a valve oven and was not designed for precise temperature

contol)

b) there were small air leaks which caused baseline shifts during the

n-pentane and ethane peaks, (the shifts were found by running an analysis of the carrier gas) and

c) there were indications that column 3 had been contaminated and

needed to be regenerated; this caused extreme tailing of the

methane peak.

Either of the latter two problems could produce the observed scatter in the

computed heating value. Additional tests should be made to determine the

precision of this configuration under better operating conditions.

33
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Comparison of pentane peak heights showed that the peak heights using

configuration B were twice that of configuration A. A sample containing

was analyzed using configuration B; the peak eluted as a single sharp

peak instead of the broad double peak produced by configuration A.

4.3.2. Digital Integrator Evaluation

The purpose of this work was to directly compare the accuracy and

precision of two different programmable digital integrators. All digital GC

integrators use voltage to frequency converters and counters to convert the

detector output voltage into peak areas. The primary difference in integrators

is in how they treat the converted signal. Both integrators used in this

evaluation employed sophisticated software programs; these programs identified peaks, baseline segments and small peaks riding on the tail of larger

peaks. Also, they compensated for transient baselines when computing peak

areas. Both integrators were programable so that automatic adjustments,

which were unique to the particular analysis, could be made during the

analysis. The primary differences between the two integrators were that

the software programs used different peak detection algorithms and that integrator B had considerably more programming capabilities; however, this

versatility was unnecessary for analyzing vaporized LNG samples.

Table 4.8 shows the results of a direct comparison between the two integrators. For these tests, both integrators were connected directly to the GC

detector output. Although integrator B has significantly greater scatter for some of the components, the precision in the heating value. for both instruments was comparable.

During the last two days of a four day test period both integrators

produced one or more extraneous results. The outliers appeared to occur

randomly among the integrators which excluded the GC as the cause. We

suspect that the outliers were caused by power fluctuations since the

integrators were on different circuits; the GC detector power supply was connected to a constant voltage transformer. Shortly after these tests

there were several power fluctuations severe enough to shut down the integrators .

4.4. Determination of the Effect of Operating Variables on Gas Chromatograph Analysis Accuracy and Precision

Variation in any of the operating parameters listed in table 4.7 could

affect analysis precision and accuracy. However, variables such as column

temperature will be electronically controlled. Therefore, they will be con- stant unless the set point is changed. The variables most subject to change

are sample amount (i.e., sample pressure since a fixed volume sample loop is

used) and carrier gas flow rate because it must be set manually.

35
Table 4.10 lists the results of two tests using column configuration A

and both integrators. In one test we injected samples at pressures of 13.7,

21.1 and 8.6 psia (94,145 and 59 kPa) ; the calibration sample pressure was

13.7 psia (94 kPa) . The table shows that the precision was insensitive to

sample pressure. However, there was an apparent linear relationship between

bias and sample pressure. This test indicates that maintaining the sample

pressure within + 10 percent of that used for calibration will keep the bias

to less than 0.025 percent in the computed heating value.

The observed bias was caused by the method the integrators used to

determine the peak area. Unless the peak was very large and sharp, part of

the peak area was lost during the baseline determination. The absolute

amount of area lost remained nearly constant as the peak area changed,

provided that the peak width at the half-height did not change. Therefore,

the relative amount of area lost decreased with increasing peak size.

Since the methane peak was so large there was a negligible amount of area

lost during baseline determination. However, this was not the case for all

other components except the pentanes. (The pentane peak areas were so small

that the effect was within the data scatter.) This explains why the apparent methane content decreased and the ethane through butane contents increased with increasing sample injection pressure.

In the second test the carrier gas flow was varied by + 7 percent.

Integrator A results were insensitive to the flow variation, whereas, integrator B showed a bias in the computed heating value. This bias was caused

by the method used to establish baseline between the nitrogen and methane

peaks. During these tests integrator B was programmed to force a baseline

at a specified time. The time was set at the bottom of the valley between

3 the two peaks (see figure 4.6) when the carrier gas flow rate was 26.5 scm /min.

Increasing the carrier gas flow rate made the valley bottom occur before the

forced baseline. Therefore, the forced baseline caused the integrator to

ignore part of the methane peak; this lowered the apparent methane content

and raised the apparent composition of the other components. This problem

can be eliminated by having the integrator automatically select the valley

bottom as the baseline when two peaks are not completely resolved.

Based on these tests it appears that the precision and accuracy of the

computed heating values are uneffected by changes of + 7 percent in the

carrier gas flow rate. This conclusion strictly applies only to configuration A. However, it should apply to other column configurations which have

comparable time spacings between valve switches and peak elutions.

36
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37
4.5. Sample Handling Procedures

Typically, the LNG sampling procedure will include the filling of gas

sample containers. Therefore, we need to know which filling procedures are

the most reliable and if there are any effects of storage which could change

the sample composition over a period of time. Considering the filling

procedures described by Miller [12] (see discussion in Section 3.2) and our

own past experiences, we feel that the fill and purge technique along with

purging at a constant flow rate are the simplest and most reliable; however,

when using the latter technique, some method of flow measurement is desirable . In using the purge and fill technique we must know how many purges are adequate to remove the original gas. Miller [12] states that 3 to 8 are sufficient; the ASTM standard [13] recommends 10 at one point and 3 to 8 in

another. The number depends upon the line pressure because the important

factor is the number of sample container volumes of gas, at ambient pressure

(assuming ideal gas behavior) , which pass through the sample container.

Assuming complete mixing, 10 volumes of gas should be adequate. However, we

felt that a test was necessary to determine:

a) the number of purges required, both in filling the sample cylinder

and in purging the lines to the GC, and

b) the effect of sample "aging" which could change the apparent com- position.

4.5.1. Test Apparatus and Procedure

Figure 4 . 8 shows a schematic of the apparatus for evaluating sample

handling techniques. In the first test we determined the number of purges

necessary to reduce the air concentration to below the detectable limit on

the GC. We used 150 cm^ stainless steel sample cylinders with valves at

each end; the valves contained teflon packing and Kel-F stem tips. The

valves were fitted with a gland and nut for making an 0- ring coupling to the

sample line. The sample cylinders were not pretreated in any way. However,

they were pressure checked to 1500 psi (10 MPa) and vacuum checked with a helium leak detector. In this test, we attached a sample cylinder to valve

V5. Initially, several analyses were made directly from the prepared mixture cylinder. In addition to noting the nitrogen content of the mixture,

we also recorded the ratio of the methane to nitrogen peak areas. (This is

a sensitive method for detecting air leaks.) To make sure that air was in

the sample cylinder initially, we evacuated the manifolding between valves

V2 and V3, with V5 and V6 open, but V7 closed; after closing V5, V7 was opened to let air in. Next the manifolding was pressurized to 30 psig (0.3

MPa) with the mixture by opening valves VI and V2. To purge and fill the

sample cylinder we would alternately open valve V5 with V7 closed, then

close V5 and open V7 ; V7 was left open just long enough to bleed the pressure

38
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39
to near ambient. After the desired number of purges, valve V2 was shut and

the manifolding evacuated through V8 . During this evacuation, valve V5 was

open but V6 closed. Next we cracked open valve V6 to fill the manifold to 2 psig (0.11 MPa) . After filling the manifold, valve V5 was closed and V6

opened. Opening valves V3 and V9 evacuated the manifold and GC sample loop.

After V9 was closed we cracked open valve V5 to fill the line with sample

gas and the analysis started. Originally the GC sample loop was purged

several times, but tests showed that one 20 to 30 second evacuation and fill was sufficient. However, if there was sufficient pressure in the sample

cylinder, we repeated the evacuation and fill at least once.

4.5.2. Evaluation of Results

Analyses were taken on samples from cylinders purged and filled 4, 6,

10 and 14 times. Only the last one indicated that all of the air was re- moved. This is equivalent to 42 sample container volumes of gas at ambient

conditions, four times more than would be expected if there was complete

mixing.

In the second test we looked at sample aging to see if processes such

as adsorption on sample cylinder walls would alter sample composition.

Again we used sample cylinders initially containing air and used 14 purge

and fills with a sample pressure of 30 psig (0.3 MPa). However, this time

the sample containers were filled at the O-ring coupling adjacent to valve

V4 ; for analysis we attached the sample cylinders to valve V5 and followed

the line and GC sample loop purging procedure outlined above. To ensure

that the change in composition, if any, was not due to biases in the GC

analysis, the prepared mixture from the cylinder was analyzed before and

after each sample cylinder analysis. Analyses were made at 1/2, 4, 24, 48

hours and 50 days after filling; in all cases the samples were within one

estimated standard deviation of the original mixture for all components.

Additional tests (see section 5.2.1.1) showed that continuous purging

also was a satisfactory sample collecting technique. However, the sample

container was purged the equivalent of 14 or more purge and fills. The gas

throughput was estimated by monitoring the pressure, flow rate (5 to 11

standard liters per minute) and time.

4.6. Conclusions and Recommendations

4.6.1. Accuracy and Precision of Analysis by Gas Chromatography

Based on the results of comparative tests it was found that a gas

chromatograph-digital integrator system was more accurate and precise than mass spectrometry. Additional tests showed that the gas chromatograph produced a bias (i.e., the total uncertainty consists of only analytical precision) of 0.02 percent, or less, in the computed heat value provided that:

40
a) the response factors for computing the composition are the average

of three or more calibrations,

b) the gas chromatograph and digital integrator operating parameters

remain constant during calibration and analysis runs, and

c) the calibration and unknown mixture compositions are comparable.

Test results showed that gas mixtures within the anticipated LNG composition

range given in table 2.1 can be analyzed by gas chromatography using only

one calibration gas (which is within the same range) without producing

biased results.

The total uncertainty in computing the heating value routinely can be

less than + 0.1 percent. This assumes:

a) taking three or more replicate analyses and averaging the computed

heating value,

b) making three or more calibration runs prior to the analyses and

averaging the resulting response factors for each component,

c) using a calibration gas which has a total uncertainty in the

composition which, neglecting the specific heating value of each component,

corresponds to an accuracy of + 0.03 percent in the computed heating value

(if the calibration gas is prepared by a commercial vendor, an independent

verification of the composition should be made)

,

d) using a gas chromatograph-integrator system with a known precision

of 0.06 percent, or better (based on three standard deviations), in the

computed heating value, and

e) following the sample injection procedures described previously

(sections 4.1.1.2 and 4.1.1.3) for gas analysis.

Appendix 7.3 outlines how to compute the total uncertainty and how the

number of calibration and analysis runs affect the uncertainty; also, it

provides a method for rejecting a given analysis.

If precise analysis of is unnecessary, column configuration A

should be used for analyzing vaporized LNG samples. If the pentanes and

peak areas need to be precisely known, column configuration B is recommended;

however, further tests are needed to insure that the configuration will be

as precise as configuration A. Also, other column configurations need to be

evaluated.

To maintain the maximum accuracy and precision, the sample amount and

carrier gas flow rate should be kept constant to within + 7 percent. It is

recommended that a high quality rotameter be used to monitor the flow

rate; the rotameter can be calibrated with a simple soap bubble flowmeter.

Direct comparison of two different integrators showed that the two instruments had comparable precision. Based on all of the tests (see section 4.3.1.1

and 4.3.2), we conclude that, at present, the digital integrator is less precise

than the gas chromatograph employing a thermal conductivity detector. Therefore,

the most precise analysis will be one in which the integrator "sees" the sharpest

41
peaks and the least baseline fluctuations before and after peaks. To maximize

the precision, a programmable integrator should be used.

4.6.2. Sample Handling

Tests showed that both the purge and fill technique and the continuous

purge technique were accurate methods for collecting vaporized LNG samples.

However, both techniques require some care to insure that the cylinder has

been purged properly.

Commercially available stainless steel sample cylinders are recommended

for collecting gas samples. No special preparation of the cylinders is

required prior to their use. Tests showed that stainless steel cylinders do

not alter the hydrocarbon content over a six week period. (However, stainless steel is not inert to sulphur compounds.)

4.6.3. Recommended Criteria for Selecting a Gas Chromatograph- Integrator

System

Based on our experience we recommend that the following features be

included in any gas chromatograph-integrator system dedicated to routine

analysis of vaporized LNG samples:

a) Automatic valve switching - this is required to insure that the

right valve is switched at the right time.

b) Thermal conductivity detector — this is the only detector that is

sensitive to all the components in natural gas and is linear in

response over the anticipated concentration ranges (i.e., the

output signal is directly proportional to the concentration) . Hot

wire filaments are preferred over thermistors because they provide

superior stability, longer operating life and fewer anomalies of

operation [20] . The instrument should contain a thermal protect

device to minimize the risk of oxidizing the filaments. To maximize sensitivity the detector cell volume should be as small as possible

c) Isolated power supply -- this is necessary to prevent electrical

noise generated by oven temperature controllers from entering the

detector circuitry. The detector power input should be connected

to a constant voltage transformer to minimize effects of line

power fluctuations.

d) Carrier gas flow control by inlet pressure — this is preferrable

to mass flow control when the analysis involves valve switching [18].

A two-stage pressure regulator should be used to keep the inlet

pressure constant.

e) Readily accessible valve and column connections — this is needed

to make routine maintenance and leak checking easy.

f) Programmable digital integrator — this is necessary to maximize

the analytical precision. A memory protect feature should be used

42
to prevent losing programs during momentary power failures. A

constant voltage transformer should be connected to the integrator

to minimize noise due to line power fluctuations.

4.6.4. Recommendations for Future Work

If C;-+ hydrocarbons must be analyzed precisely, additional testing of

column configuration B is needed to determine the analytical precision of

the method. Other column packings should be considered for column 1 of this

configuration

A survey of the open literature shows that there is no widely accepted

method for analyzing vaporized LNG samples. An extensive study should be

made to determine the best gas chromatographic technique for analyzing LNG

type mixtures. The study should include selecting the best column packings,

column configurations and detectors. Capillary columns should be considered

because these columns produce extremely sharp peaks which are ideal for use with digital integrators. Once the gas chromatograph system has been

selected, extensive tests should be made to establish representative values

for the precision and accuracy of the technique.

5.0 LNG SAMPLING

The sampling tests included both laboratory and field tests. The laboratory tests provided close control of all operating variables whereas the

field tests permitted evaluation of a full scale sampling system.

The chronological order of the tests and the variables considered for

their effect on sampling accuracy and precision were:

a) laboratory tests (Probe Evaluation) - sampling rate, LNG flow rate,

temperature, pressure, degree of subcooling and three probes;

b) laboratory tests (Vaporizer Evaluation) - sampling rate, temperature, degree of subcooling, LNG flow rate and two vaporizer

designs

c) field tests (LNG Flow Facility Test 1) - three probes and three

vaporizers

d) laboratory tests (General Tests) - accumulator residence time,

vaporizer outlet temperature, pressure drop upstream of

vaporizer, heat leak to sample probe and presence of heavy

components (C

5 +) in the LNG,

e) field tests (Shipboard Tests) - sampling rate and comparison between liquid and vapor sampling,

f) field tests (LNG Flow Facility Test 2) - sampling rate, heat leak,

start-up transients and three variations of a vaporizer design.

This section discusses all the laboratory tests before describing the field

tests

43
5.1. Laboratory Tests

5.1.1. Laboratory Facility

This section discusses all aspects of the laboratory facility with the

exception of the gas analysis equipment; this is discussed in section 4.1.1.

5.1.1.1. Laboratory Scale Apparatus

Figure 5.1 shows a schematic of the laboratory scale apparatus used in

this work. The cryogenic portion of the apparatus was contained in an evacuated double walled dewar which was 33 inches (840 mm) deep and had a 10-3/4 inch (270 mm) inside diameter. The LNG vessel, which was 8-1/2 inch

(215 mm) long with an outer diameter of 8 inches (203 mm), had an inner

volume of roughly 6 liters; the wall was copper and the two end plates were

brass. A centrifugal pump circulated LNG through a turbine flowmeter, with

a range of 0.2 5 to 2.5 gpm (0.016 to 0.16 L/s), and through the test section

between valves Tl and T2. All of the lines in this loop were 1/2 inch (12.7

mm) O.D. copper tubing except for a 3 inch (76 mm) long section containing

1 inch (25 mm) O.D. copper tubing just downstream of valve Tl . This short

section acted as a mixing chamber to reduce flow turbulence caused by the

valve. The test section was a 6-3/4 inch (171 mm) long straight section.

It contained two probes — an upstream facing pitot tube and a side tap.

Both probes were mounted vertically and were made of 1/16 inch (1.59 mm)

O.D. by 0.023 inch (0.58 mm) I.D. stainless steel tubing. There was roughly

6 inches (150 mm) of line between the probes and valves T4 and T5.

Besides the pitot tube and side tap, a "reference" probe was located in

the straight-run leg of a tee positioned just upstream of valve Tl. Since

the flow into the tee was downward, the reference probe was in essence

located on the bottom of the line. There were 8 inches (200 mm) of 0.023

inch (0.58 mm) I.D. stainless steel tubing between this probe and valve T3.

Valves Tl through T6 were bellows valves which were located inside the

insulating vacuum space at LNG temperature. They were actuated by stem

extensions protruding through the top plate of the apparatus. Valves T3

through T6 were mounted on a brass plate which was soldered to the top of

the mixing chamber.

After a probe was selected by opening either valve T3, T4 , or T5, the

sample passed through 1/16 inch (1.59 mm) O.D. by 0.023 inch (0.58 mm) I.D.

stainless steel tubing to one of three vaporizers. If the sample went to

the reference vaporizer it first passed through valve T6 and 8 inches (203

mm) of tubing; valve T6 was a needle valve used to provide additional pressure drop to prevent sample backflash, i.e., flow reversal due to vaporization. The reference vaporizer consisted of a 5 inch (127 mm) long section

of 1/16 inch (1.58 mm) O.D. by 0.051 inch (1.28 mm) I.D. stainless steel

tubing and a 12 inch (304 mm) long section of 1/8 inch (3.18 mm) O.D. by

0.101 inch (2.56 mm) I.D. stainless steel tubing. The sample was vaporized

44
To To

M1XCH4 N 2 Vac Vent

T17 To Gas

Chromatograph

I | 41 | i Relief it it i JWW? I 1 1 Lsrf- TR T7

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r-klj-oJ-cfe

00k Sampler

T3X T4X T5X 0 n . Ref. Tn I Jpr Sample Probes

Insulating Vacuum Space'

Figure 5.1. Schematic of laboratory scale apparatus.

45
by passing a low voltage, high amperage DC current through the two sections

of tubing. To prevent shorts, the two ends of the vaporizer were epoxied

into micarta couplings. The reference vaporizer was located less than 1/2

inch (13 mm) from where the sample line left the vacuum insulated space.

After the sample left the vaporizer it went to a manifold containing a

2 liter accumulator, through a 0 to 11.4 liter per minute (1pm) rotameter

and back to the LNG vessel. The lines between the vaporizer and rotameter

were 1/4 inch (6.35 mm) O.D. by 0.190 inch (4.83 mm) I.D. copper tubing; the

copper tubing downstream of the rotameter was 3/8 inch (9.53) O.D. by 0.343

inch (8.71 mm) I.D. The accumulator could be isolated by closing valves T7

and T8; to maintain the sample flow, valves T9 and T10 (a regulating valve)

were opened when the accumulator was isolated. Samples could be taken from

the accumulator through valve T14 and from the bypass line through valve

T17.

The second vaporizer, vaporizer A, contained an electrically heated

vaporizing element, an adjustable back pressure regulator and a 0 to 30 psig

(0.1 to 0.3 MPa) pressure gauge in a single unit. The heating element was a 1-1/4 inch (31.8 mm) wide by 28 inch (71.1 cm) long section of 100 mesh, 316

stainless steel screen wrapped around a 1/2 inch (12.7 mm) O.D. stainless

steel tube. The diameter of the tube plus screen was 0.71 inches (18 mm).

The vaporizer was designed to have the sample flow through the screen perpendicular to the axis of the tube. Also, the vaporizer contained a bypass

valve and a pressure relief valve to protect the pressure gauge; both of

these valves were capped in this study. Approximately 15 inches (381 mm) of

stainless steel tubing connected the probes to vaporizer A. To prevent

premature vaporization the line was vacuum jacketed to within 1 inch (25 mm)

of the vaporizer inlet. When using this vaporizer, valves Til and T12

replaced the function of valves T7 and T9

The third vaporizer was a Cook sampler. Whereas the reference vaporizer and vaporizer A were for continuous sampling, the Cook sampler was designed for the batch sampling. Since the LNG sample was used to cool the

sampler, the lines were piped to return the vapor to the LNG vessel; otherwise, the mixture would be depleted too quickly. The line from the probes

to the sampler was roughly 15 inches (381 mm) long and vacuum jacketed.

Liquid nitrogen (LN

2

) was used as the refrigerant in this study. The

LN

2 vessel was 9-7/8 inches (251 mm) in diameter and 10-3/4 inches (273 mm)

long and could contain about 10 liters of liquid. The LNG vessel was cooled

by liquid flowing from the LN

2 vessel and through a coil wrapped and soldered on the LNG vessel. Cold nitrogen vapor leaving the coil went to

another coil soldered on a 1/8 inch (3.2 mm) thick copper plate located

roughly 2 inches (50 mm) below the top plate. All lines into the vacuum

space were in thermal contact with this plate to reduce heat leakage. After

46
leaving the copper plate the nitrogen went to valve Nl and to a 0-44 liter

per minute full scale rotameter and/or to bypass valve N2 . When the apparatus was temporarily shutdown, e.g., overnight, nitrogen gas vented through

another line which contained a relief valve set at 8 psig (0.16 MPa)

During these periods the LN

2 vessel needed to be filled every 24 to 2 8 hours. The LNG vessel cooled at a rate of 1 to 2 K per day during idle

periods

To minimize radiation heat leak in the vacuum space, the apparatus was surrounded by a copper radiation shield. This shield was fastened to the

LN

2 vessel and extended up to the copper plate.

5.1.1.2. Instrumentation

The temperature was measured using a platinum resistance thermometer

(PRT) calibrated on the IPTS-68 temperature scale. The PRT was encased in a copper sheath pressurized with helium gas and positioned near the bottom of

the LNG vessel. To measure the resistance we used a one ma constant current

source with a potentiometer and a nanovolt null detector. The thermometer

current was monitored by measuring the voltage drop across a 100 ohm standard resistor. Initially, we had the output from the null detector go to a power regulator; this regulator powered either a 120 or a 230 ohm heater

wrapped on the LNG vessel. Although the temperature control was good (+

0.01 K) , crosstalk developed between the power regulator and the null detector. This control method was dropped and thereafter the temperature was controlled by manually adjusting the LN

2 flow rate; using this method we could control the temperature to + 0.0 3 K or better.

The saturation pressure of the LNG was measured with a 0 to 100 psia (0

to 6.9 MPa) quartz bourdon tube pressure gauge; this gauge was calibrated

against an air dead weight gauge. The difference between the LNG pressure

in the test section and in the LNG vessel was measured with a 0-300 inches

of water (0 to 0.07 5 MPa) differential pressure gauge; this gauge was not

calibrated during this project.

5.1.1.3. Safety features

Since the project involved flammable fluids all vents on the LNG system

were tied to the room vent system. In addition, all vacuum pump outlets

were connected to the same vent system. A relief valve, set at 120 psig

(0.93 MPa), was located on the sample return line; this relief valve lead to

the vent system. Finally, the insulating vacuum system had a relief valve

connected to the vent and a pressure switch-solenoid valve combination. If

the vacuum pressure increased to 100 microns (13 Pa) , or, if there was a power failure the solenoid closed, isolating the vacuum space from the

vacuum pump.

47
5.1.1.4. Recirculation pump motor

In the early stages of the project we had problems with motors to drive

the recirculation pump. The same pump had been operated in liquid helium

using a small three phase induction motor [21] . However, this motor had too

much slippage when used with LNG (the density of LNG is four times greater

than that of liquid helium) . Two small motors in tandem still did not

provide sufficient torque. Next we went to a 1/7 HP (106 watt) DC brush

motor. The motor had sufficient torque but operated only 100 hours before

the brushes failed. We replaced the brushes and used the same motor for

another 90 hours. We then purchased and installed a larger three phase

induction motor (1/2 hp (373 watt) at 10,000 rpm) ; it worked satisfactorily

for the remainder of the project.

5.1.2. Experimental Procedure

5.1.2.1. Cooldown and Filling Procedure

After checking for leaks the insulating vacuum space was evacuated for

-4

15 or more hours. By this time, the pressure was down to 10 mm Hg (0.1

Pa) or less. The complete LNG system was evacuated and back filled several

times with high purity nitrogen which passed through a molecular sieve

purifier. The cooldown was started by filling the LN

2 vessel with liquid

nitrogen. With bypass valve N2 (see figure 5.1) wide open it took about 2 hours to bring the apparatus to 110 K. Once at LNG temperature, all instruments and the pump were tested and

the system was checked for cold leaks. If all was well the prepared mixture

was condensed into the LNG vessel. Using a pressure of 40 to 50 psi (0.27

to 0.34 MPa) above the mixture's saturation pressure it took about one hour

to fill the LNG vessel; when the LNG vessel was full there was a sudden rise

in the pressure of the LNG system. At this point the startup was complete.

5.1.2.2. Preparation of Known Mixture

Because the accuracy of Sampling-Measurement Systems needed to be

known, prepared mixtures of known composition were required in the laboratory scale apparatus. Of the several preparation methods considered, it was decided that the fastest and most accurate method was to fill a large

3 (1.75 ft (49.6 L) ) gas cylinder with pure fluids and analyze the resulting

mixture. (Size and weight limitations of the mass balance made preparation

by weight unfeasible.) Partial pressures were used as a guide for estimating how much of each component should be added. Prior to filling, the

cylinder was evacuated while being warmed with a heat lamp for at least 48

hours. The cylinder was filled to 1100 psi (7.59 MPa), which was well

below the dew point pressure of the mixtures used here, and warmed with heat

lamps for at least 6 hours. To enhance mixing, the cylinder was alternately

heated in vertical and horizontal positions; when in the horizontal position

a heat lamp was placed at each end of the cylinder. Next, a sample of the

48
mixture was analyzed on the GC; the cylinder then was heated for several more hours before making another analysis. If the analyses did not agree,

the procedure was repeated until they did. (It never took more than 4 8 hours to obtain complete mixing.) Next, a series of at least 6 analyses were

made on the mixture and the results averaged to determine the composition as accurately as possible.

After filling the LNG vessel the cylinder pressure was 100 to 150 psig

(0.79 to 1.14 MPa) . The mixture remaining in the cylinders was analyzed

again to see if the composition had changed. Also, this gas mixture was analyzed several times during each operating day so that day to day shifts

in the analysis could be detected. Table 5.1 gives the final sets of

analyses for the prepared mixtures.

5.1.2.3. Operating procedure

The daily startup consisted of bringing the system to the desired

operating condition and calibrating the gas chromatograph. The reference

vaporizor and vaporizer A required 15 to 30 minutes, depending upon the

sample flow rate, to establish steady-state conditions. The flow through

the vaporizer had to be stable to obtain temperature control because the

sample stream constituted 25 to 50 percent of the heat load on the system.

(The only other major heat input was from the pump motor.)

After establishing the desired operating conditions the accumulator was isolated by closing valve T8 and valve T7 or Til (see figure 5.1), depending

upon the vaporizer used. (Operating the Cook sampler is discussed below.)

To ensure a representative sample of the mixture leaving the vaporizer, the

sample passed through the accumulator for at least 10 minutes under steadystate conditions. Immediately after isolating the accumulator either valve

T9 or T12 was opened (valve T10 remained open) to avoid upsetting the system. At this time the operating variables could be changed so that the

system would be stable when the next sample was ready to be taken. Under

normal operation the power input to the reference vaporizer was set so that

the tubing just downstream was warm to the touch; vaporizer A contained a thermostated heater set at 125°F (40°C)

To analyze the trapped sample in the accumulator the line between valve

T14 and the GC was evacuated by opening valves VI, V5 and V6 (see figure

4.1) After closing valve V6 , the line then was pressurized to about 2 psig

(0.11 MPa) by opening valve T14. This purge and evacuate procedure was repeated three times; next valve T14 was left open and VI closed. Then the

analysis procedure described in section 4.1.1.3 was followed.

To draw a sample from the accumulator bypass line, valves V2 and V7 were opened to evacuate the line connecting V2 and T16. After closing V7

valve T17 was opened to pressurize the line to about 2 psig (0.11 MPa).

After repeating the purge procedure three times, valve V2 was closed and T17

49
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50
left open. Next, the analysis procedure was followed. The sample flow in

the bypass line was uninterrupted during the purging procedure.

Initially, at least two analyses were made on each sample. Since each

analysis took 14.5 minutes, this limited us to analyzing a maximum of two

samples per hour. Once the integrator was repaired, only one analysis was made on each sample unless the results were more than three estimated standard deviations, for gas analysis alone, from the expected values. In this

case, another analysis was made; in all cases, duplicate analyses were

within one estimated standard deviation of the first analysis for all components. The prepared mixture from the cylinder was analyzed several times

a day. Most often these were made during a temperature change and/or a LN

2 vessel filling — each of which took about 30 minutes. The prepared mixture

also was analyzed at the end of the day after shutting down the apparatus.

Sample flow to the Cook sampler was obtained by closing valves T6 , Til,

and T12 and by opening valves T7 and T8 and the valves on the Cook sampler

(see figure 5.1). Once the sampler contained only liquid the valves on the

sampler were closed and it was allowed to warm up. Next the accumulator was evacuated by closing valve T8 and opening valve T13 for several minutes.

After closing valve T13, the downstream valve on the Cook sampler was opened.

Then the accumulator was isolated by closing valve T7 and the mixture analyzed following the procedures described above.

5.1.2.4. Control of operating variables

The operating variables initially considered in this study were temperature, Reynold's number in the test section (Re), difference between the

pressure at the sampling point and saturation pressure (Ap) and sampling

rate (Q) . The temperature was maintained by balancing the refrigerant flow

against the heat input. Usually temperature control was held by having only

valve Nl open (see figure 5.1); however, when operating at high sample flow

rates, bypass valve N2 had to be opened as much as 1/4 turn. Both Re, i.e.,

flow rate in the test section, and Ap were set by adjusting pump speed and

valve T2. (In all tests reported here valve Tl remained wide open.) Valve

T15 controlled the sampling rate.

5.1.3. Experimental Results

The laboratory tests were divided into three phases:

a) Probe Evaluation

b) Vaporizer Evaluation

c) General Tests.

The first two phases were conducted prior to the first flow facility

tests. The last series of tests were made to explain the unexpectedly poor

results obtained at the flow facility. The second flow facility tests and

the shipboard tests followed the general laboratory tests.

51
5.1.3.1. Probe evaluation

The purpose of this phase of work was to:

a) determine which, if any, operating variables affected the reliability of the three probes,

b) determine which of the test probes was the most reliable,

c) show that the reference probe produced samples of the same composition as the test probes, and

d) establish the precision and accuracy of the reference probe.

The reason for using a reference probe was to determine the mixture composition. This probe design is unfeasible for most industrial applications.

However, to prove the probe's reliability required tests using mixtures of

known composition. In the probe evaluation three different compositions

were used and two of these were mixtures of known composition.

In addition to the composition, the following operating variables were

considered

a) three sample flow rates (Q)

,

b) four Reynold's numbers (Re) in the test section,

c) two operating pressures, i.e., temperatures, and

d) five differential pressures (Ap) i.e., the difference between the

pressure at the sampling point and the saturation pressure of the

mixture.

Table 5.2 lists the values of the variables according to run number and

table 5.3 gives the estimated standard deviations in composition, ideal gas

heating value and liquid density for each probe in each test. Except where

noted in the text, average values of composition, ideal gas heating value,

and liquid density for these tests are indistinguishable statistically from

the corresponding values given in table 5.1. (Appendix 7.4 lists the raw

data for all sampling tests.) Except for Test 2, the estimated standard

deviation in heating value and density for the sampling data is presented as

a percentage of the average values obtained from analyses of the prepared

mixture in the gas cylinder. In Test 2 the percentage is based on the

average of all of the probe analyses.

Test 1 The purpose of this test was to establish the feasible operating range

of the variables and to identify operating variables which affect the reliability of the probes. Prepared mixture 1 was used in this test. Figure

5.2 shows the deviation in the computed ideal gas heating values as a function of probe and run number. The deviation is the difference between the

heating value obtained via the probe sample and the heating value given in

table 5.1 for mixture 1, all divided by the tabular value. Replicate points

for a given run number represent the results of replicate gas analyses. We

found that the occasional large scatter between replicate analyses was

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caused by a GC integrator malfunction (see section 4.2). Although this

scatter confuses the results somewhat, figure 5.2 (and table 5.2) shows that

the pitot tube tends to be more erratic. The results showed that it is

possible to obtain representative samples at a Ap as low as 1.8 psi (0.012

MPa) ; the pressure drop in the sampling system prevented us from trying a lower Ap.

A statistical analysis of the results from the reference probe and the

prepared mixture indicate that the reference probe collected a representative sample. The figure indicates that most of the computed heating values

were slightly higher than the prepared mixture; this bias apparently was caused by not making three independent GC calibrations each day. Figure 5.2

shows that all three probes sampled the same liquid.

Test 2 The first test was not a statistically designed experiment; therefore,

the effect of each operating variable could not be quantitatively determined. Nitrogen was added to the mixture to bring the nitrogen content to

roughly 1.34 mol % for Test 2. (Two intermediate concentrations of 0.55 and

4.34 mol % nitrogen content were made before reaching the 1.34 mol % level;

the data taken with these mixtures are given in Appendix 7.4 but not discussed here.) In this test the sampling rate was varied between 2.4 and 7.2

slpm (standard liters per minute, at 70° F (21° C) and 14.7 psia (0.101 MPa)).

Figures 5.3 and 5.4 show the scatter, on a percentage basis about the mean,

in the computed heating value and density as a function of run number and

probe. There seems to be a day-to-day effect in the scatter with the first

and last days being the worst and best, respectively. The only plausible

explanation for this behavior is that the contents may not have been well

mixed on the first day (this same trend seems apparent in figure 5.2).

In these tests the prepared mixture was condensed into the LNG vessel

from the top. This unfortunately minimized the mixing during the filling

process. The same procedure was followed when adding nitrogen. In each

case the sampling tests began immediately after filling and the only mixing

occurred during the recirculation of the LNG.

Table 5.4 lists the estimated standard deviations of the composition,

heating value and liquid density as a function of probe and sampling rate.

The test results show that the sampling rate has a strong effect on sampling

precision.

Test 3 In this test we varied the temperature, flow rate and pressure difference but kept the sampling rate constant at 4.2 or 5.6 slpm. Prepared

60
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mixture 4 was used in this test. Recirculation pump characteristics permitted operation at both low and high flow rates (Reynolds numbers of 17,000

to 31,500) at a low Ap (3.6 psi (25 kPa) ) , but only the low flow rate at the

high Ap (10.1 psi (70 kPa) ) . Shortly after starting this test the turbine

meter stopped working. However, we had already noted the pump speed re- quired for the desired flow rates at each Ap when operating at 111 K and

used these to set the flow rate. We assumed that the same Ap and pump speed

were required to obtain the desired flow rates at 120 K. This was verified

later when the turbine meter began working again.

Figure 5.5 shows the deviation in the ideal gas heating value for this

test. Neither the figure nor a statistical analysis of the data (see table

5.3) show an effect due to Re, Ap or T. Again, the pitot tube had the most

scatter. The nitrogen content in the liquid was 0.024 mol% lower than in the

prepared mixture 2; calculation showed that this could have been caused by

nitrogen going into the vapor phase during condensation into the apparatus.

Test 4 The purpose of this short test was to ascertain the effect of laminar

flow on sampling precision. The difference in operating variables between

this test and test 3 was that the Reynold's number was 1500 or 17,000 instead

of 17,000 or 31,500. In this test the low flow rate was maintained the first

day while Ap and temperature were varied; the second day the flow rate and

Ap were varied while the temperature was held constant at 111 K. Figure 5.6

shows the deviation in ideal gas heating value. During the first part of the

second day the power supply for the pump frequently tripped the circuit breaker.

Each shutdown caused the vaporizer to warm up. We believe that the increased

scatter during the first part of day 2 was caused by the reference vaporizer

not being at steady state conditions when the gas sample was trapped in the

accumulator. Once the power supply problem was fixed (prior to run number 177)

the scatter became comparable to that of the previous day.

The results indicate that the probes work equally well in laminar and

turbulent flow. The statistical analysis shows that the nitrogen content

decreased by 0.006 mol% when going from 111 to 120 K. This effect had not

been detected in any other test, nor for any other component. However, by

the time of this test roughly 100 samples had been withdrawn from the apparatus, thus increasing the vapor space in the LNG vessel. Calculations

showed that this apparent temperature effect could have been caused by

the increased amount of nitrogen in the vapor phase at 120 K.

5.1.3.2. Vaporizer evaluation

The probe tests showed that the reference probe to be the most reliable

of the three probes tested. Therefore, the reference probe was used in the

evaluation of vaporizer A and the Cook sampler. Since the Cook sampler is

64
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66
is designed for batch sampling, it is not a continuous vaporizer like the

reference vaporizer and vaporizer A. Preliminary testing of the Cook sampler

showed that it would not work well on the laboratory apparatus. Cook [22]

indicated that it is designed for use with high sampling rates so that the

total sampling time would be less than 30 seconds. In our tests the sampling rate was so low that it took at least 30 minutes to cool the sampler

down. By this time the sampler valves were very cold and leaked when closed.

Because of this problem and because the primary interest was in continuous

sampling systems the Cook sampler was not tested further on the laboratory

apparatus. However, vaporizer A was found to work at low sampling rates; it was evaluated in the same manner as the probes. Prepared mixture 4 was used

in both tests. Table 5.5 lists the values of the operating variable and 5.6

lists the estimated standard deviation in composition, ideal gas heating

value and liquid density.

Test 1 The purpose of this test was to evaluate vaporizer A at two sampling

rates (2.0 and 5.6 slpm) , temperatures (111 and 120 K) , pressure differences

(3.6 to 10.1 psi (25 to 70 kPa) ) and flow rates (Re of 18,000 to 35,000);

these conditions are comparable to those used for the probe evaluations.

Figure 5.7 shows the deviation in heating values for this test. The estimated standard deviation in the heating value for this vaporizer was about

20 times greater than that observed for the reference vaporizer during the

probe tests. However, the precision of the reference system was poorer in

this test than in any other test. This increased scatter was due to either

incomplete accumulator purging and/or to taking a sample too quickly after

starting the reference vaporizer. Three points on the third day showed that

the reference system precision was a factor of three worse than usual.

During these runs the accumulator residence time was 40 to 120 seconds; the

samples were analyzed after 10 minutes of purging the accumulator. The fourth

reference sample was taken after the accumulator was purged for 20 minutes

this sample was representative of the prepared mixture.

Once it was obvious that vaporizer A was not performing wellj we made

several minor changes to try to reduce the scatter. Originally the sampling

rate was set by using valve T15 (see figure 5.1); starting with run 137, the

sample rate was set by adjusting the pressure regulator on the vaporizer.

This did not improve the results. During most of this test the throttling

valve (valve T6, figure 5.1) for the reference vaporizer was roughly 1/4

open. We made two reference vaporizer runs (runs 108 and 109) with the

valve wide open, thinking that the valve might be preventing backf lashing

(this was the purpose of the valve) . With the valve wide open, the pressure

drop in the lines between the probe and the two vaporizers was comparable.

67
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Having the valve wide open did not diminish the performance of the reference

probe. Near the end of the test the sampling rate was increased to 16 slpm

(runs 137, 140 and 141) or 10 slpm (the last five runs) . Since the higher

sampling rate seemed to improve the vaporizer performance, another test was planned to determine the effect of high sampling rate.

Test 2 In this test we operated at 111 K and a Ap of roughly 3.8 psi (27 kPa)

and varied the Reynold's number between 16,000 and 33,000 and sampling rate

between 6.7 and 19 slpm. Figure 5.8 shows the deviation in the heating

values for this test. The estimated standard deviation in heating value for

vaporizer A in this test was 0.25 percent as compared to 0.76 percent for the

first test but still high compared to the typical 0.05 percent obtained for

the reference vaporizer. We do not know why runs 188 and 189 are so different

from the rest of the data.

5.1.3.3. General tests

To explain the poor results obtained in the first flow facility test

(see section 5.2.1.1) it was necessary to conduct additional laboratory

measurements. These tests considered whether sampling precision could be

affected by:

a) eliminating the sample accumulator,

b) increasing or decreasing the vaporizer outlet temperature,

c) heat leak to the sample probe,

d) minimizing the pressure drop upstream of the vaporizer,

e) decreasing the sample residence time in the accumulator, and

f) having relatively high concentrations of heavy hydrocarbons (C^'s

through Cg's) in the LNG.

The following operating variables were held constant during each test:

a) temperature and pressure,

b) sampling rate, Q (except when varying accumulator residence time),

c) Reynold's number (Re) in the test section, and

d) differential pressure, Ap.

Table 5.7 gives the values of the operating variables for these tests.

These variables values were in the range known to give good results in the

previous laboratory tests. Prepared mixture 6 (see table 5.1) was used in

tests 1 through 5; LNG, which was prepared by condensing natural gas con- taining C,+ was used in the last test. The reference vaporizer was used in

D all of the tests.

Test 1

The purpose of this test was to determine the sampling precision when

drawing samples from the accumulator bypass line while having the accumulator

bypassed. In all previous laboratory tests (but not the first flow facility

test) samples had been taken only from the accumulator. Table 5.8 and

72
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73
Table 5.7. Date, run number and operating conditions for general tests; reference

vaporizer used throughout these tests; R, S, and P refer to reference,

side tap and pitot tube probes, respectively.

Test 1. Temperature = 123.0 K, Pressure = 36.0 psia (248 kPa), Sampling Rate = 5.0 slpm, Reynolds Number = 22,800, AP = 5.0 psi (35 kPa).

Date Run Number Probe Accumulator Bypassed

4/14 191 R No 192 Yes

ii

i yj Mi es

ii 1 QA. i yt

„ INO

ii

1 33 „i es

ii 196 " Yes

ii 197 No

n i no NO

n

1 99 n Yes

ii CUV Yes 4/15 201

" No

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II INO

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II 207 Yes

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II 211 P Yes 212 II No 4/19 213 R No

ii 214

n Yes

n 215 S Yes

n 216

ii No

ii 217 P Yes

n 218 n No

ii 219 s No

ii 220

II Yes

ii 221 p Yes

M 222 II No

ii 223 R Yes

ii 224

H No

ii 225 P No

ii 226

ii Yes 4/20 227 R Yes

228

ii No

H 229 S Yes

ii 230 n No

74
Table 5.7. (Continued)

Test 1 . (Continued

Date Run Number Probe Accumulator Bypassed

4/20 231 R Yes

n 232 ii No

ii 233 P Yes

ii 234 n No

ii 235 S Yes

n 236 ii No

ii 237 ii Yes

ii 238 n Yes

Test 2. Temperature = 123.0 K, Pressure = 36.0 psia (238 kPa), Sampling Rate = 5.0 slpm, Reynolds Number = 22,800, AP = 5.0 spi (36 kPa), Probe = side

tap.

Date Run Number Vaporizer Power, Watts Accumulator Bypassed

4/21

4/22

4/25

239

240

241 242

243

244

245

246

247

248

249

250

251 252

253

254

255

256

257

258

259

260

261

262

263

264

0.0

99.6

98.6

97.5

98.1

0.0

98.6

97.5

97.0

H 96.5

ii 63.2

62.0

Yes

NoYes

No

Yes

NoNo

Yes

No

Yes Yes

No

NoYes

No

Yes

No

Yes

NoYes

NoYes

No

Yes No

No

75
Table 5.7. (Continued)

Test 3. Temperature = 123.0 K, Pressure = 35.5 psia (245 kPa), Sampling Rate

5.0 slpm, Reynolds Number = 22,900, Ap = 5.0 psi (35 kPa).

Ua te Kun Numuer Probe Probe Heater

Watts

4/25 265 S 0.1

ii £00 9fiR ii 0.4

M CO9fi7/

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ii COO n 6.7

H/ CO 9CQ co? n

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270 ii 0.1

II 971 CI \ ii 0.4

II 979 CI C

ii 1 .0

II 97"5 CI O

ii 1 .7

II 274 ii 3.8

II 275 ii 6.7

4/29 299 ii 0.0

M 300 ii 1 .7

n 301 ii 6.7

ii 302 ii 1 .7

ii 303 n 6.7

ii 304 n 0.0

M 305 n 6.7

n 306 ii 1 .7

n 307 ii 0.0

ii 308 n

1 .7

n 309 ii 0.0

n 310 ii 6.7

Test 4. Temperature = 123.0 K, Pressure - 35.3 psia (243 kPa), Sampling Rate = 5.0 slpm, Reynolds Number 23,500, Ap = 5.0 psi (35 kPa), Probe = side

tap.

Date Run Number Needle Valve,

4/26 276 Yes

n 277 Yes

ii 278 No

n 279 Yes

n 280 No 4/27 281 No

ii 282 Yes

ii 283 No

ii 284 Yes

ii 285 No

I 286 Yes

ii 287 No

ii 288 Yes

n 298 No

ii 299 Yes

76
Table 5.7. (Continued)

Test 4. (Continued)

Date Run Number Needle Valve, Throttled

4/27 291 No 292 Yes 5/02 311 - No 312 No 313 No 314 No

31 5 No 316 No

317 Yes 318 Yes 319 Yes 320 Yes

321 Yes

Test 5. Temperature = 112.0 K, Pressure = 16.8 psi (116 kPa), Ap = 8 psi,

Reynolds Number = 9,100 (56 kPa), Probe = side tap.

Date Run Number Sampling Rate Accumulator

slpm Residence Time, s

4/28 293 12.2 10.5

294 8.6 15.0

295 5.9 21.8

296 12.2 10.5

297 8.6 15.0

298 12.2 10.5

Test 6. Sampling Rate = 5 slpm, Ap = 5.0 psi (35 kPa), Reynolds Number = 22,000.

Date Run Number Temperature Pressure prQbe

5/11 322 123.5 32.2 222 S

n 323 " "

11 "

ii 224 " " "

"

ii 325 " " "

"

ii 225 11 " " "

ii 327 " " "

" 5/12 328 121.5 32.1 221

ii 229 " " "

11 330

|| II II H II

77
Table 5.7. (Continued)

Test 6. (Continued)

Date Run Number Temperature J**TMTM Pro be

5/12 332 121.5 32.1 221 S

ii 333 " " " "

ii 234 " 11 11 11 5/16 335 120.0 40.1 276

336

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ii 240 11 " 11 "

M 241 " " "

1

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figure 5.9 show that the scatter increased markedly when the accumulator was

not used. This indicates that the vaporization process generates inhomogeneities in the sample which can be eliminated by time averaging the sample

in an accumulator. The accumulator was used in all remaining tests.

In addition to taking discrete samples we continuously fed a small gas

sample stream 10 cc/min) to an ultrasonic detector. It was hoped that by

continuously monitoring overall composition fluctuations (there was no easy

way to selectively monitor one component) a periodic behavior could be

found. Samples from the bypass line, accumulator, prepared mixture cylinder

and from a pure methane cylinder were analyzed continuously. Only the pure

methane sample showed no composition fluctuations. The other samples showed

random fluctuations with the bypass sample having the largest scatter. The

fluctuations in the prepared mixture and accumulator samples were comparable

in magnitude. This indicates that even gas mixtures withdrawn from cylinders will contain some composition variations. Unfortunately, it was not

possible to quantify the fluctuations in terms of mol percent.

Test 2 The dew point temperature of the LNG mixtures in the first flow facility

test was well below ambient temperature; however, it was thought that a possible problem could have been the use of a long vaporizer warmed only by

cold water. To simulate this condition in the laboratory we varied the

power to the vaporizer; this, in effect, changed the vaporizer length.

Three different power levels, 0, 62 and 98 watts, were used. With no input

power, the vaporizer plus approximately 5 feet (1.5 m) of the 1/4 inch O.D.

(6.4 mm) copper tubing downstream of the vaporizer became coated with frost.

At 62 watts the vaporizer outlet temperature was warm to the touch; this was

the temperature that was used in all other laboratory tests. At 100 watts,

the tubing just downstream of the vaporizer was too hot to touch for more

than a second. At all three power levels the accumulator remained at am- bient temperature. Only the side tap probe was used in this test and the

values for the 62 watt case were taken from the previous test.

Table 5.9 shows that only the 0 power case affected the sampling precision. These results tend to indicate that it is better to vaporize the

sample quickly. It was thought that the higher heat input might offset the

effect of bypassing the accumulator. However, table 5.9 and figure 5.10

show that the increased heat input did not improve the sampling precision

when the accumulator was bypassed.

Test 3 In the first flow facility test the lines from the probes to the vaporizers were uninsulated. Therefore, it was thought that heat leak could

cause the observed sampling problems. To test the effect of heat leak we

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attached 42 ohm heaters to the pitot and side tap probe. Since the probe

line was 1/16 inch (1.6 mm) O.D. tubing it was impractical to wrap heater

wire directly on the tubing. The heater wire was wrapped on a copper cylinder which was soft soldered to the probe lines approximately 1.5 inches (38

mm) from where they entered the test section. The heaters covered approximately 0.5 inches (13 mm) of the 1/16 inch (1/6 mm) stainless steel tube

2 2 giving a heat transfer area of 0.10 in (63 mm ).

In the first part of the test we heated the side tap and took samples

at input powers of 0.10, 0.42, 0, 1.7 and 6.7 watts — this corresponds to

0.2, 0.7, 0, 3 and 11 percent of the power (62 watts) to the vaporizer. As

figure 5.11 shows there was no apparent effect on sampling. At 6.7 watts

the heater shorted out. The test was repeated for the pitot tube. Although,

statistically, there was no apparent change in the precision, increasing the

heat seemed to decrease the methane and nitrogen content (runs 269 through

275 in figure 5.12). Therefore, it was decided to repeat the test with the

heat input randomized instead of systematically increasing the input power.

Table 5.10 lists the estimated standard deviations. This test showed that

the apparent trend noted before for nitrogen was coincidence and that there was

no detectable effect on the sampling precision.

During the last run of this test, this heater shorted out too. When

the apparatus was disassembled we found that both heaters were unsoldered

from the tubing. Soft solder (50% Sn, 50% Pb) melts at 490 K [23] and the

thermal conductivity for 304 stainless steel is roughly 0.12 watts/cm-K

[24]. Using these values, the heater length and tube dimension, and 6.7

watts input power, thermal conductivity calculations show that the temperature of the inside tube wall could have been as high as 480 K. Therefore,

there had to be film boiling inside the probe line. The effect of heat leak was studied in the second flow facility test.

Test 4 During previous tests the needle valve upstream of the reference vaporizer was used to provide some pressure drop in the liquid phase which would

reduce the possibility of backf lashing. In the vaporizer evaluation (see

section 5.1.3.2) we opened the needle valve and found no apparent change in

the sampling precision. If the needle valve could be omitted it would

eliminate an operating variable in the LNG sampling system. Therefore, we

wanted to confirm the previous results in this test using the side tap

instead of the reference probe.

When wide open there was an estimated 0.03 psi (0.2 kPa) across the

needle valve (valve T6, figure 5.1); in this case regulating valve T15 was used to control the sample flow rate. The maximum pressure drop (^ 1.5 psi

(10.3 kPa) ) across the needle valve was obtained by using it to control the

sampling rate; in this case all valves downstream of the needle valve were

wide open. (We estimated the pressure drop in the vaporizer and the line to

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the vaporizer to be 1.0 psi (6.9 kPa) and 1.8 psi (12.4 kPa) , respectively.)

When controlling the sampling rate with the needle valve, the sampling rate

had fluctuations of ^ + 50 percent of the average reading.

Table 5.11 and figure 5.13 show that the amount of pressure drop across

the needle had no apparent effect on the sampling precision. However, there

may have been sufficient resistance in the line to the vaporizer to prevent

backflashing . This test was repeated in the second flow facility test.

Test 5 The first test in this phase of work clearly indicated that an accumulator was needed. However, the minimum acceptable residence time in the

accumulator was not determined. In this short test we varied the residence

time between 10 and 22 seconds. Residence times for past tests were in the

range of 15 to 30 seconds. The 10 second residence time corresponded to a full scale reading on the rotameter used to measure the sampling rate.

Figure 5.14 shows the heating values for this short test. Although the

first point (293) appears too high it still is well within the error limits

of gas analysis alone. There were too few data points to do a statistical

analysis on each residence time. However, an analysis of the whole group

indicated that the estimated standard deviation in computed heating values

was comparable to the best values obtained in other laboratory tests (^ 0.02

percent)

Test 6 In all of the previous laboratory tests, prepared mixtures containing

nitrogen and methane through butane were used. The LNG for the first flow

facility test was prepared by condensing natural gas obtained from the local

gas utility. The liquid contained roughly 0.2 mol percent hexanes and

higher hydrocarbons. It was thought that the presence of heavy components

may have caused some of the sampling problems experienced in the first flow

facility test. Therefore, additional natural gas from the local utility was condensed and transferred into the laboratory apparatus. While holding all

operating variables constant, a series of runs was made to determine the

effect of heavy components on the sampling precision.

Table 5.12 lists the average values and estimated standard deviations

for this test; figure 5.15 shows the deviation in the heating value. (The

deviation is defined here as the difference between the measurement and

average value divided by the average value for the given mixture.) Runs

were made with different nitrogen levels. All of these analyses were made

using column configuration A (see section 4.3.1.1). The estimated standard

deviations for the first two days were comparable to previous laboratory

tests. (The 0.005 mol percent value for the estimated standard deviation of

nitrogen was typical for the gas chromatograph used on this test.) However,

the imprecision was much greater in the heating value on the last day. This

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was due to an increase in the scatter of the normal pentane and the C,+

6 component peaks. An estimated standard deviation of 0.04 mol percent in

the Cg+ peak corresponds to nearly 2 Btu/scf (0.08 MJ/m3

) or 0.17 percent in

the ideal gas heating value. The problem was not in sampling but in the

inability of the digital integrator to correctly determine the area of the

peak. (This problem is discussed in section 4.3.1.1).

At the time of these tests we did not have a calibration gas containing

pentanes; therefore, response factors for the pentanes and C

& + (assuming the

peak contained equal parts of n-hexane and n-heptane) were estimated by

taking the ratio of the response factor for the given component to that of

n-butane [25] and multiplying that by the response factor for n-butane as determined from calibration. The same approach was used for the oxygen and

carbon dioxide peaks except that nitrogen, instead of n-butane, was used in

the ratio.

Based on the results of this test, the presence of heavy components does

not affect the sampling precision but they can affect the analytical precision.

This test pointed out the analytical problem of correctly integrating the Cg+

backflush peak.

5.2. Confirmation Tests

It was important that the conclusions obtained from the small scale laboratory tests be confirmed in a facility comparable to the proposed industrial installation. Three confirmation tests were made — two at the NBS

LNG Flow Facility and one aboard the LNG tanker El Paso Consolidated . The

shipboard test was made after completing the laboratory tests and between

the two flow facility tests.

5.2.1. NBS LNG Flow Facility Test 1 The LNG flow facility [26] is an outdoor pilot plant which has been

used primarily for LNG flowmeter measurements. Figure 5.16 shows a schematic of the facility and table 5.13 lists the pertinent operating data.

For the sampling tests a 3 ft (0.9 m) long test section was inserted roughly

10 ft (3 m) downstream of the recirculation pump. All lines in the flow

loop were 2.5 in (72 mm) diameter stainless steel pipe and all lines except

the test section were vacuum jacketed.

Table 5.13. LNG flow facility operating characteristics

Temperature Range 95-140 K

Temperature Stability + 1 K or better

Pressure Range 19-110 psia (0.13-0.76 MPa)

Pump Discharge Pressure

(above weigh tank pressure) 2.7-30 psid (19-207 kPa)

LNG Flow Rate 20-200 gpm (76-760 Lpm)

Reynold's Number 10,000-100,000

94

Vaporized samples from the test section were collected in 150 cm sample

cylinders for analysis in the laboratory GC. For these tests we used column

configuration A (see section 4.3.1.1). The vaporized samples also could be

sent to a gas gravitometer and combustion calorimeter. These units were

located approximately 50 ft (15 m) away in a constant temperature room. The

residence time of gas in the line between the sample panel and calorimeter

was 1.6 minutes. Additional gas samples could be taken just upstream of the

calorimeter and gravitometer.

It was possible to send gas samples directly to a process gas chromatograph. But since it measured only the concentration of nitrogen, methane,

ethane, carbon dioxide and propane it was not used in these tests. Also,

there was a pitot tube (up and downstream facing pitot)-air vaporizer sampling system [27] downstream of the sampling test section. It was used only

in the first test.

During the initial startup the flow loop was purged with dry nitrogen

and then cooled down with liquid nitrogen which was recirculated through the

flow loop. After cooldown, LNG was transferred into the weigh tank. For

the sampling tests the LNG was pumped from the bottom of the weigh tank and

returned to the top of the weigh tank. The temperature was controlled by

adjusting the liquid level in the liquid nitrogen heat exchanger.

The "true" composition of the LNG in the flow facility could not be

measured. This limited the tests to comparing only the precision of the

various sampling systems. However, the composition could be held constant

throughout an operating day. System venting during shutdown caused day to

day shifts in the composition. LNG for this test was made by condensing the

natural gas supplied by the local gas utility. The gas was dried with a desiccant and the carbon dioxide was removed by filtering the liquid [27].

In Test 1 we wanted to compare three probes -- a side tap, a side tap

with a capillary opening and an upstream facing pitot tube; two vaporizers — a water heated coil and vaporizer A; and the Cook sampler. Figure 5.17

shows a schematic of the sampling system (a sample accumulator was nofc- used) . All three probes were mounted horizontally in the test section and

were 6 in (152 mm) apart. The test section was enclosed in a 5 in (127 mm)

section of copper tubing. The annular space was evacuated to provide insulation. (However, during the tests it became obvious that the vacuum was very poor because a heavy layer of frost formed on the outer tube.) All

three probes were made of 1/8 in (3.2 mm) O.D. by 0.101 in (2.56 mm) I.D.

stainless steel tubing. The probe lines were vacuum jacketed 6-1/2 in (165

mm) beyond the 5 in (127 mm) tube. The pitot tube had a 90° bend with the

intake on the flow section center line.

96
Vent

Sample

Bottle

Sampling Panel

To Calorimeter &

Gravetometer

XT8

To Vacuum

T7

T If T6

To Vent txjT5

Relief

Cook

Sampler

t

X

T4

T3

XT2

H

2 0/Glycol

Bath

Pitot

Tube

<] LIMG Flow

Sampling Test Section

To Vacuum

Sample

Bottle

To Vent

Figure 5.17. Schematic of sampling system used in flow facility test 1.

97
It was thought that if part of the pressure drop between the probe and

vaporizer could be taken in the liquid phase there would be no danger of

backflash; hence, it would not matter how the sample was vaporized downstream. Therefore, a capillary probe was built which contained a 1/4 in

(6.4 mm) long section of 0.007 in (0.18 mm) I.D. tubing. This was soldered

into the 1/8" (3.2 mm) O.D. tubing. The capillary section produced roughly

5-1/2 psi (38 kPa) pressure drop for a liquid flow corresponding to 8 slpm

of gas flow.

The water heated vaporizer consisted of 10 ft (3 m) of 1/4 in (6.35 mm)

O.D. x 0.190 in (4.83) I.D. copper tubing immersed in a water-glycol bath

which was at ^ 30°F (-1°C) . During operation the coil would have a ice

layer which extended about 3 ft (0.9 m) along the tubing in the bath.

5.2.1.1. Test results

The results of this test were extremely poor; the best agreement between two samples was 0.04% in the heating value. However, this was fortuitous because the typical scatter was on the order of one percent. The

scatter was unaffected by the probe and vaporizer used. It was found that

the heating values of the samples taken five minutes apart from the same sampling system varied by 0.7 percent; samples taken simultaneously from the

same stream at the panel and at the gravitometer inlet differed by 1.5

percent. However, during all of these tests the calorimeter and gravitometer remained steady. (The gas specific gravity is much less sensitive to

composition than the heating value, e.g., in the composition range studied a 1.5 percent change in the heating value corresponds to only 0.4 percent

change in the specific gravity.)

Initially, it was thought that the scatter could be caused by the

different methods of filling the sample cylinder. Samples taken at the

panel were purged and filled 14 times; the sample cylinders at the gravitometer/calorimeter inlet were filled by continuous purge through. To test

the effect of sample cylinder filling procedure on precision, one of the

calibration gases was connected to the sample panel. Using comparable

sample flows and pressures to those used in the other tests, samples were

taken at both the panel and the gravitometer/calor imeter inlet. The resulting sample compositions were within the error of the gas analysis alone;

therefore, the sample cylinder filling procedure was not a problem.

The possibility that the scatter was caused by either liquid composition fluctuations or by the presence of vapor in the test section was considered. The stability of the densimeter in the LNG flow facility indicated

that there were no composition fluctuations. The possibility of two phase

flow was eliminated because the vortex shedding flowmeter would have behaved

erratically in two phase flow. At this point it was decided to make additional laboratory tests (see section 5.1.3.3) to determine the cause of the

poor sampling precision.

98
Even with the erratic sampling precision, the following qualitative results were obtained:

1. It was not possible to obtain reliable samples from the Cook sampler

as tested; this sampler should have been insensitive to the problems experienced with the continuous samplers. However, it is possible that valve T2

(figure 5.17) was leaking during the warm up period or that the reduction in

sample pressure when filling the sample cylinder caused partial condensation. (The ambient air during these tests was 30 to 40°F (-1.1 to 4.4°C)).

2. Based on the band width of the gravitometer trace, the up and down

pitot-air vaporizer and the capillary probe-water vaporizer systems produced

more precise samples than did the side tap-vaporizer A system. The gravitometer band width for the capillary probe-water vaporizer samples and

gravitometer calibration gas (air) were comparable. Also, it was found that

the heating values for the side tap-vaporizer A samples were 0.5 to 1 percent

higher than those from the other two systems; the heating value difference

between these two systems was less than 0.2 percent.

3. The capillary probe is not a feasible probe in industrial applications where entrained solids could cause plugging. In the flow facility

there were small amounts of solid carbon dioxide which plugged the capillary

line

5.2.2. Shipboard Tests

Using the information obtained in the laboratory and first flow facility

tests, a full scale sampling system was designed for tests aboard the LNG

tanker El Paso Consolidated . Sampling tests were made at Canvey Island,

England during the ship's cargo system trials. Two sampling systems were

installed — a liquid sampling system was installed on the 3 inch (76 mm)

diameter header to the ship's LNG vaporizer; a gas sampling system was placed on the 16 inch (406 mm) diameter vaporizer outlet header. Sampling

the gas phase provided a check on the liquid sampling system.

Figure 5.18 shows a schematic of the liquid sampling system and table

5.14 lists the component dimensions. The system had a 1/4 inch, schedule 80

pipe (13.7 mm O.D. x 7.67 mm I.C.) side tap probe mounted horizontally on

the header. All valves, fittings and tubing upstream of the sample panel

were stainless steel; tubing in the panel was copper and the other components were brass. Except for the filter connections and union just upstream

of the vaporizer, all connections upstream of the vaporizer were socket

welds. The line between the header and vaporizer was wrapped with a one

inch (25 mm) layer of fiberglass pipe insulation and sealed with duct tape.

Valves Tl and T2 were bellows valves with the valve components welded together. (We have had success using these valves in cryogenic applications.)

Valve T2 was a metering valve; it and the back pressure regulator were used

to control the sampling rate.

99
100
Table 5.14. Dimensions of LNG Sampling System used on Shipboard Tests

Component Length

inches (mm)

Outer Diameter

inches (mm)

Inner Diameter

inches (mm)

Vaporizer Header 3.5 (88.9)

(3 in pipe)

Side tap and 1 i ne between header and

Valve Tl

Ah (114) 0.540 (13.7)

{h in Sch 80

pipe)

0.302 (7.67)

Line between Valve

Tl and filter (contained a long radius

90° bend)

11 (279) 0.25 (6.4) 0.180 (4.57)

Line between filter

and Valve T2

*3 (76) 0.25 (6.4) 0.180 (4.57)

Line between Valve

T2 and union at vaporizer

18 (460) 0.125 (3.18) 0.101 (2.56)

Vaporizer tubing

(formed into a 4

in (102 mm) diameter helix)

45 (1140) 0.188 (4.76) 0.164 (4.15)

Vaporizer Casing

(with welded cap

ends)

20 (508) 6.00 (150) 5.94 (151)

Line from Vaporizer

to union (contained

a long radius 90°

bend)

11 (279) 0.25 (6.4) 0.180 (4.57)

Line to Valve T3 14 (356) 0.25 (6.4) 0.180 (4.57)

Accumulator

(with welded cap

ends)

24 (610) 6.00 (152) 5.94 (151)

101
The nitrogen purge connection (which was insulated up to valve T3) was

used for displacing air from the sampling system; it was located downstream

of the 60 micron filter so that nitrogen could be used to back purge the

filter, if necessary. However, the filter never clogged during these tests.

Because of film boiling, a precise (+ 20 percent) design of the sample

vaporizer would have been extremely tedious. Therefore, the design was

based on the warming of methane gas from 115 to 310 K. A flow rate of 65

slpm was used. We assumed that the steam side temperature was constant at

340°F (171°C) this corresponds to the temperature of 205 psia (1.41 MPa)

steam isentalpically expanded to 60 psia (0.4 MPa). The heat transfer

resistances on the steam side and in the tube wall were negligible compared

to the gas phase resistance; properties of methane [28,29] at 150 K were

used in the calculations. The final vaporizer tube length was twice the

length computed using the above assumptions.

The steam inlet line, vaporizer and condensate line were insulated;

this was done primarily for personnel safety. Condensate from the vaporizer

was used to warm the bottom of the accumulator to provide additional mixing.

The accumulator was sized to provide a 30 second residence time for a sample rate of 65 slpm and sample pressure of 50 psig (0.45 MPa). The

length to diameter ratio was 2.5 and the volume was 11 liters.

The sample panel layout was designed so that the sample flow could be

maintained with or without sample cylinders in the system. The back pressure regulator was extremely useful for making minor changes in the sampling

rate and setting the sample cylinder pressure.

The gas sampling system consisted of a 1/4 inch, schedule 80 pipe (13.7 mm O.D. x 7.67 mm I.D.) side tap mounted vertically on the top of the outlet

header, a block valve and 1/4 inch (6.35 mm) O.D. by 0.190 inch (4.83 mm)

I.D. copper tubing going to the sample panel. This panel had the same layout as the liquid sample panel but included a needle valve upstream of

the accumulator for flow control. This system was designed for a vaporizer

outlet pressure comparable to the inlet pressure (65 psig (0.055 MPa)).

However, the outlet pressure was only 1.5 to 2 psig (0.112 to 0.115 MPa);

this reduced the sampling rate to approximately 1 slpm from the anticipated

10 or more slpm.

Gas analyses were made using a gas chromatograph containing a 30 ft

(9.1 m) long column of DC 200/500 on Chromasorb P and a 5 ft (1.5 m) molecular sieve 5A (MS) column. The column valve configuration permitted backflushing the DC 200/500 column and bypassing the MS column. Nitrogen and

methane were resolved on the MS column. Ethane through the butanes were

separated on the DC 200/500 column; the column was backflushed to obtain a C

5 + peak. Digital integrator A was used to measure peak areas. The precision

of the analytical system was found to be 0.06 percent in the computed heating value.

102
5.2.2.1. Test Results

The primary purpose of this test was to examine the precision of the LNG

sampling system. The LNG was totally vaporized downstream of the sampling

probe and the analysis of this gas was to serve as the basis on which to evaluate the liquid sample analysis. However, the analyses of the vaporized gas

produced erratic results that are felt to be more a function of the low pressure of the gas than composition change in the pipeline. Of the six sets of

sampling data taken, only the second set contained sufficient samples taken

under constant vaporizer conditions to directly compare the gas and liquid

sample compositions. See figure 5.19. Since composition variations were

probably less of a factor than the gas analyses, separate means and standard

deviations were computed for the liquid samples and for the gas samples for

each of the six data sets. See table 5.15. The heating values are computed

using the A.G.A. method [1] and assumes equal parts of iso and normal pentane;

the liquid phase densities were computed from the extended corresponding states

model [3] (Appendix 7.5 lists the compositions and operating parameters for all

of the tests)

During the first data set the vaporizer inlet pressure varied erratically

(30-56 psig) . Therefore, these samples were taken only to gain experience in

operating the sampling system. For data set 6, the chromatograph-integrator

system was behaving erratically with respect to the butane peaks. For these

reasons, the results for these two data sets, as given in table 5.15, do not

represent a properly operating system under stable operating conditions and

were not included in subsequent data analysis.

Although the conditions under which liquid samples were taken for data

sets 2, 3, 4, and 5 are considered acceptable for sampling purposes, some points

were deleted from the data analyses. It was found that the LNG sampling system

worked well at sampling rates of 12.5 slpm or greater; however, two samples,

run No. 19 at 3.4 slpm and run No. 57 at 6.2 slpm, yielded poor results and wer

omitted from the analyses. Also during these tests the accumulator residence

time of the "good" liquid samples ranged between 28 and 76 seconds, and on this

basis run No. 25 was also omitted. Run No. 31 was omitted from the data analyse

because it did not go through the accumulator and run No. 35 was omitted as the

evidence indicated that it was an outlier. For data set 4, run No. 51 was analy

three times; the first analysis, being completely wrong, was omitted.

An estimate of standard deviation was calculated based on data sets 2, 3,

4, and 5. For the liquid samples the value obtained was 0.72 Btu/scf with 17

degrees of freedom. An upper 99% confidence bound for the standard deviation

based on this estimate is 1.18 Btu/scf, or 0.1% based on a heating value of

1200 Btu/scf.

103
eW/flAI '3fllVA 9NI1V3H OBlfldlAlOG

J3S/nia '3m VA 9NI1V3H QBlfldlAlOG

104
Table 5.15. Average values and estimated standard deviations in composition, real qas heatinq value,

and liquid density for shipboard tests.

Data Sample Number Average Value and Estimated Standard Deviation in Set of

Points Composition, mol % Heating

Value

BTU/SCF

(MJ/m3

)

Liquid

Density

N2 CH 4 C 2 H 6 (-3^8 n C4H10 g/cm-*

1

* T=114.6

L

G

7

1

0

u.

0

201

1 A 0 14j

209

85.864

3.101

83.762

10.063

2.252

11. 553

2.983

0.716

3.442

0.452

0.155

0.541

0.416

0.134

0.494

0.020

0.020

0.0

1165.8

35.9

(43.428)

(1 .338)

1176.7

(43.833)

0.4682

0.0107

0.4752

2 T=114.6

L 7 0

0 110 003 85.149

0.036

10.558

0.024

3.176

0.013

0.511 0.004

0.460

0.003 0.0450.003

1165.8

0.5 (43.428)

fo n?n

S

0.4712

0.0001

G 8 0

0 109007 85.112

0.049

10.573

0.051

3.184

0.009

0.515

0.005

0.460

0.002

0.047

0.057

1166.3

0.5 (43.446)

(0.020)

0.4713

0.0001

3 T=114.6

L 4 0

0 015

017 82.544

0.031 12.353

0.038

3.863

0.023

0.623 0.0050.563

0.004

0.040

0.028

1195.8

0.41 (44.547)

( 01 5 S

\

• u 1 3 J

0.4799

0.0001

G 4 00 016

016 82.2580.563

12.611

0.496

3.898

0.101

0.614

0.027 0.5530.002

0.051

0.008

1198.3

5.6 (44.638)

(0.211)

0.4806

0.0016

4 T=115.0

L 8 00 0006

0015

79.045

0.080

14.515

0.050

4.854

0.023 0.800

0.005 0.719

0.004

0.067

0.003 1236.2

0.9 (46.050)

0.4914

0.0009

G 4 0

0 001

002 78.9710.134

14.530

0.075

4.868

0.024

0.802

0.008

0.721

0.004

0.108

0.082

1237.9

2.8

(46.112)

(0.102)

0.4916

0.0007

5 T=116.0

L 2 0 0 78.367 0.055

15.042 0.0465.000

0.013 0.8080.0015 0.720

0.006

0.064

0.010

1242.6

0.7 (46.289)

( 027)

0.4917 0.0002

G 2 0.0. 001

002 78.2800.091

15.139

0.037

5.006

0.064

0.800

0.009

0.714

0.002

0.062

0.006

1243.0

0.9 (46.304)

(0.035)

0.4919

0.0003

6 * T=116.5

L 7 0 0 77.905

0. 09

15.361

0. 07 5.1120. 022

0.821 0.0060.733 0.005

0.078

0.007

1247 .

5

0.9

(46.471

)

(.035)

0.4926

0.0006

G 4 0. 0 78.216

0.356

15.229

0.284

5.081

0.106

0.692

0.225

0.724

0.004

0.057

0.040

1242.6

5.6 (46.287)

(0.209)

0.4912

0.0015

These tests occurred during unstable conditions (refer to text for details) and the values for the means and standard deviations are not meaningful.

105
A commercial "primary standard" calibration gas was used for gas chromatograph calibrations. During the calibrations it became obvious that the

reported and actual calibration gas compositions were different. This discrepancy was found by comparing the nitrogen to methane response factor ratio

with the ratio obtained from Dietz's data [25]. Table 5.16 gives the manufacturer's stated composition and error limits along with the composition

determined in our laboratory. Column configuration A was used with mixture

H as the calibration gas. The difference between the stated and actual

composition represents a 0.5 percent error in the heating value. This means

that if the stated compositions had been used there would have been a bias

of 0.5 percent in the computed heating value. This experience points out

the importance of accurately knowing the composition of calibration gases

used in custody transfer. If possible the stated composition should be

verified by an independent gas analysis laboratory.

5.2.3 LNG Flow Facilitv Test 2 At this point, we had a full scale LNG sampling system which had worked

in the field. However, another field test was necessary to determine:

a) the criteria for establishing sampling rate,

b) the effect of using steam versus electricity for sample vaporization,

c) the effect of not using a needle valve to control sampling rate, and

d) the effect of heat leak.

Figure 5.20 shows the flow schematic for this test. We built three vaporizers -- two steam heated and one electrically heated. One of the steam

vaporizers had the same dimensions as the electric vaporizer; the second

steam vaporizer had a 50 percent larger tube inner diameter and the tube

length was 40 percent longer than the other two vaporizers. Table 5.17

gives the important dimensions of the vaporizers and sampling systems;

figure 5.21 is a schematic of one of the sampling systems. The old test

section was replaced with a test section containing two side taps mounted

horizontally. The side taps were 1/4 inch schedule 80 (13.7 mm O.D. x 7.67 mm I.D.) stainless steel pipe. Except for the vaporizers, all dimensions on both sampling systems were identical. Therefore, by operating two

vaporizers simultaneously we made direct comparisons between vaporizer

designs. The LNG sample lines to the vaporizers were wrapped with a 1/2

inch (13 mm) thick layer of fiberglass pipe insulation and sealed with duct

tape. Also, the steam vaporizers, steam inlet lines and condensate lines

were insulated for personnel safety.

Valve SI was a block valve (see figure 5.21) and valve S2 a metering

valve; both valves were all welded stainless steel bellows valves. Neither

valve was degreased before use and stem extensions were not used.

106
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CD .c: s_ +J o c/1 Q. c

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to c to o TO ai cu Q. > E >

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TOc o

CO TO c S_ > TO S- to to a

(U TO TO XJ TO c +-> LO CU to SOJ "O cu CU .E c JZZ JZZ 1— TO +J +->

107
108
Table 5.17. Dimensions of LNG sampling system used in second flow

facility tests (see figure 5.21 for schematic of sampling system).

Component

Test section

Side tap and line

between test section

and valve SI 1

Line between valve £1

and filter 1 (contained

a short radius 90° bend)

Line between filter

and valve S2 1

Length

Inches (mm)

36 (914)

4-1/2 (114)

11 (279)

2 (51)

Line between valve S2

and union at vaporizer 1 13-1/2 (343)

Vaporizer 1 tubing

Vaporizer 2 tubing

Vaporizer 3 tubing

For vaporizers 1 and 2 steam casing (with

flat welded ends)

Impingement chamber

(with flat welded ends)

Line between impingement chamber and downstream union

Accumulator 1

36 (914)

50 (1270)

36 (914)

10 (254)

1-1/2 (38)

8 (200)

16 (406)

Outer Diameter

Inches (mm)

3-1/8 (79.4)

Inner Diameter

Inches (mm)

2.812 (71.42)

0.540 (13.7) 0.302 (7.67)

(1/4 in. Sch 80 pipe)

0.25 (6.4)

0.25 (6.4)

0.25 (6.4)

1/8 (3.18)

3/16 (4.76)

1/8 (3.18)

6 (152)

1-1/2 (38)

0.25 (6.4)

5.125 (130.2)

0.180 (4.57)

0.180 (4.57)

0.180 (4.57)

0.101 (2.56)

0.156 (3.96)

0.101 (2.56)

5.5 (140)

1.376 (34.95)

0.180 (4.57)

4.805 (122)

These dimensions apply to both sampling systems

109
110
The two steam vaporizer tube lengths were twice the tube length com- puted by considering only the heat transfer resistance of a pure methane gas

phase (see section 5.2.2 for more details). For this test we used a steam

generator which produced roughly 50 psia (0.34 MPa) saturated steam.

To prevent the entrainment of fine droplets in the steam vaporizer

outlet steam, an impingement chamber was included in each steam vaporizer.

The stainless steel chamber consisted of a 1-1/2 inch (38 mm) diameter

cylinder 1-1/2 inches (38 mm) long. It was constructed so that the vapor

plus mist leaving the vaporizer tube contacted the upper surface of the

chamber. The combination of impingement, sudden flow decrease and flow

reversal hopefully would eliminate any remaining liquid droplets.

The electric vaporizer dimensions were chosen to correspond to one of

the steam vaporizers so that a direct comparison between vaporizers could be

made. However, the impingement chamber was not used with the electric

vaporizer. This vaporizer consisted of thin wall (0.012 in (0.30 mm))

stainless steel tubing with electrical leads attached at each end. Since

the tubing was used as the resistive heater a high amperage (18 amps) low

voltage (4.3 volts) direct current was used. To prevent possible shorts,

the vaporizer tube was epoxied into micarta couplings at each end.

Initially, the accumulator volume was two liters but the first day's

test results showed that the accumulator was too small. Thereafter, a four

liter accumulator was used.

Analysis of the LNG used in the first flow facility test showed relatively high concentration of C^+. To obtain a more representative LNG

mixture, the LNG for this test was purchased from San Diego Gas and Electric

Company. However, even this LNG contained approximately 0.08 mol percent

C c +.

D For sample analysis, column configuration A was used. Prepared mixture

H (table 4.2) was used as the calibration gas. Both integrators A and B

were connected to gas chromatograph II so that their results could be

compared.

5.2.3.1. Test results

A total of seven tests were made in the flow facility over a four day

period. Table 5.18 lists the pertinent operating parameters and lists a comparison of measured and computed heating values and specific gravities.

The computed quantities are real gas values computed from the compositions

using the A.G.A. methods [1]. Table 5.19 gives the average values and

estimated standard deviation of the compositions and the liquid densities

computed using the extended corresponding states method [3]

Ill
a)

p 1 i p CD 1 rH CD 1 Sh u > • G

Qj 0) CD CD tO rH Cn CD C r-> * u g C P p G tO H O,

UJ +J o CD c CQ

H > Pn

O

CO r^ t/1 re rH •H rH o a> 0 10 Sh a CD - CD SH p p > p CD CD E rH CN T3

111 nj CD P P tO T3 CO -rl

g 1 t 4-J rH tO 10 in CO <W (0 CD

fC a; *rH

r»t i CO

O 0 G tOg CD CD < i H rH C r* rG (1) x* 1—

! | H m CD f—

Eh 0) Jh rd «* E (0 0 P rH rH

0)

u

U rH

g rH CO TS 10 CN

CDC 3 o CO in rrj CU >1 (0 > • rH

fd « e H

g

p CO rH > 01 33 in > rH

Tj in r- 00 >i CD ro rH in <T\ rH in o o in rH o r~

G P P O LO

O LD o •rj<O in o in o r- o rO

O o o

-H •H CO o >X1 o O ix)O U3 o o VD o VD o VD o VD o r- o P >

to

g o o o o o o o o o o o O o O o O o O o o o

<Du 0

.g

u

u

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r-< rJ

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CM ,—

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—

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to En

p CN ro ro CN

0] < CQ

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0)

112
CD 1 rH 1 h e M

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rH

T3 VDm > CD r- o o VD LD

-P -P o o o o o o H o r~ o r-~ o > a • • • • td £ o o o o o o 0u u

•H

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44 0 • • O u "3* O "3" o

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r4

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TS

CD

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CD

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4-> c

id

to

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rH

rd>

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td • a c • CD ft, >

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rH -H

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4->

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TJ -a

CD CD

to CO 3 3

CO to

4-> 4-> rH rH 3 3

to to

CD CD

5-l 54 < m

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C

rd

in

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4-> CQ 00

00rH

to

td

4J

to

CD

4-1

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4-1

44oc

r-icc

•H

C7> CD X!

CD si

4-»

4-1 td

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rH

td>

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4-1

4-) td

4-) CO

>1 a

td

CD

4-> to

CD • Si rj)

4-i

a

r-i V) to

r-i as<D

CO 5-1 •H O

si <D Eh

U

CD +J

CDE0

4->

•r-i >

tdUu

CD +J

0)E

•H

V40

r4

CD

4-) CDEO

4J •H>

rrj U

CT> CT> u

CD

4->CDe

•r-i UO

CD CD

in

CD

4-1 CDEo

4-> H>

tdu

tn

13 t 13 c c c

td id id

id td id td > o o o

4-1 ooo4-1 4-1 N N

-H -H H $4 o o a a

a

id id id > > > ooo E E E U U V)

M-l M4 44 ooo S ^ ^

rH rH rH h ti Im in vd

113
Table 5.19. Average values and estimated standard deviations in composition and liquid density for the second flow facility test.

1 Test Vaporizer Sampling Average Value and Estimated Standard Deviation in Rate

si pm Composition, mol % Liquid

Density

"2 l-2 n6 if H nT < H

1 0

1 *»5 n 1 g/cm3

2

life 511 j 2

1 14 0.0 84. 997 0^413

12. 005 0^334

?L- . tit 414

0.067

o 1 an 0.005 0.006

0. 048 o!ooo40.037 o!ooi0.083 o!ooo80.4593

0.0015

19 0.0009 0.002 84.609

0.486

j 12. 324 0.390

2.469

0.077

0.193 0.0060.232 0.007

0.049

0.002 0.0380.002 0.0840.003

0.4607

0.0016

A

1 2 13 a.o 84.454

0.831 12.439 0.673

2.506 0.132

0.196

0.010

0.233 0.013

0.049

0.002 0.0390.002 0.084 0.46100.0022

16 0.0 84.669

0.080 12.302 0.019

2.466

0.080 0.1870.004

0.220

0.005

0.044 0.0008

0.035

0.001

0.077 0.0010.4603

0.0006

2 13 0.007

0.005

83.772 0.075

12.968 0.064

2.604

0.013 0.2050.001

0.244

0.001

0.052 0.00080.058

0.001

0.090

0.001

0.4537

0.0005

B

1 22 0.011

0.003 83.8660.050

12.904 0.0372.585

0.016 0.2030.002

0.242

0.002 0.052 0.0008

0.057

0.001

0.090

0.001 0.4534

0.0005

C

2 1 16 1.611

0.024 80.026 0.118

14.712 0.1192.959 0.018

0.293 0.0060.345

0.007

0.067 0.002

0.053 0.0020.114 0.006 0.4802

0.0038

1 6.0 1.444 0.424

79.903

0.302

14.932 0.241

3.012 0.043 0.238

0.003

0.280 0.005

0.052

0.006 0.042 0.002 0.0950.008 0.4797

0.0012

D

2 9.8 1 .611 0.024 80.026

0.118

14.712 0.1192.959

J. 018 0.233u.uuz

0.274

0.003

0.051

0.001 0.042

0.002

0.090 0.005 0.4768

0.0010

2 4.9 1.665 0.71879.978

0.819

14.771 0.086 2.889

0.036 0.228

0.013 0.269

0.002 0.050

0.003

0.040

0.004

0.102

0.009 0.4795

0.0007

9.5 1.491 0.024 80.103

0.132

14.757 0.0822.956

0.025 0.2340.014

0.275

0.003 0.0520.003 0.0420.002

0.089

0.005 0.4770

0.0008

E

1 1 19 4.122

0.008

74. 153 0.01317.161

0.013

3.662 0.0060.291 0.00030.347 0.0030.077 0.0007 0.054

0.0006 0.1330.001

0.5015 0.0010

1 16.8 4.138

0.018

74.083

0.062 17.2020.059

3.669 0.015 0.292

0.001

0.349 0.001

0.077 0.0002

0.055 0.0004 0.134

0.0003

0.5020

0.0010

F

1 3 15.3 4.043

0.026 74.223 0.049

17.174 0.0383.654

0.020 0.2920.0006 0.3480.001

0.077 0.00030.054

0.0005 0.134 0.0005

0.5020

0.0012

G

l 1 16.9 3.231 0.279

74. 597 0.12917.517

0.139

3.729 0.0190.298

0.003

0.356

0.002 0.078 0.00L

0.056 0.00060.136 0.002

0. 5002 0.0005

1 Intearator A results used in this test.

2 Integrator B results used in this test.

114
Test A

Because the sampling rates would be comparable to those used in laboratory tests, two liter accumulators were used in test A. However, the test

results suggested that the accumulator was too small. Figure 5.22 shows the

deviation from the average heating value for this test. At the sample rates

used in this test the accumulator residence time ranged between 10 and 18

seconds; this same range gave good results in laboratory tests. All remaining tests were made using four liter accumulators.

Test B

As shown in figure 5.23, results of test B clearly confirmed the need

for the larger accumulator. Possible reasons for this include:

a) the use of a constant wall temperature vaporizer (as opposed to

the constant heat flux vaporizer used in the laboratory apparatus) , or

b) the presence of a finite heat leak into the sample line.

Unfortunately, we did not have sufficient time to identify the reason for

needing the longer residence time.

Two points were eliminated from figure 5.23 and from the statistical

analysis of test B results. For no obvious reason, one sample had a methane

content five standard deviations higher than the average value for the test

(both integrators gave the same result) . However, the second outlier was

the first sample taken after changing the sampling rate; it was taken less

than 20 minutes after the change. This suggested the possibility of flow

transients affecting the sampling precision.

Test C

Test C was a short test to determine if sampling system startup transients affected sampling precision. Figure 5.24 shows the deviation in heating value for this test. The deviations are relative to the average values

obtained under steady conditions in test D which was run on the same day. In

this test, samples were taken every 15 minutes after putting the sampling system in operation. Although the scatter was greater, especially in the nitrogen,

methane and ethane contents, there was no obvious trend with time. Another

sample was rejected in Test D which was one percent higher than the average

heating value in that test; it too was drawn less than 30 minutes after

changing sample rates. These results suggest that the sampling rate should

be established at least 30 minutes before taking a sample.

Test D

Test D was made to determine the sampling precision of the two steam

vaporizers at low sampling rates. The initial sampling rates were 9.8 and

9.5 slpm in vaporizers 1 and 2, respectively. At these rates neither the

gravitometer nor the calorimeter indicated the precision being diminished

for either vaporizer. These sampling rates corresponded to a linear liquid

115
3 S- o o

Cl

t+I i- lO>

s_ ai o N a*

<+- +-> o

ai O

CL ai >

T3

to > +-> >

a> ec CD +-> CL o c (/> ai

+-> s- fO T3

CD -C at E

Cl

in

CO </) cn CO LO < E UJ (8 CL CO ai

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aj E co

+-> 3 in a CL c +J E a> n3 rO o

<_> f— en he -!-> ak cxz

+j <t 03 +-> c 4-> C in

in ai O)

a>

to +j 03 Cl

+-> E o >> 03

(/) (/) aj (O CM

CL > u E Sro 03 CD o M- (/) N

C\J

%'3fl"IVA 9NI1V3H Nl N0I1VIA3Q

116
DC

LU

CO

CM 3O Sa>

14- NJ

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ra

1/1 >

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> a

a> CD 13 C CD a p

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to E

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to 0

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re CM

to T3

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oj a) to

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a.E

O +-> O CQ (O C +-> c

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a)

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n3 TJ a 4- to

COCM

5-

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117
CD

>

to

toCD

s-

<1)

CLE • 0 o

o +J

01 to J= CO c >,

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% '3mVA 9NI1V3H Nl N0I1VIA3Q

118
flow rate of 4.0 cm/s and 1.6 cm/s in vaporizer 1 and 2, respectively.

Next, the sampling rates were lowered so that the linear flow rates were

2.4 cm/s and 0.8 cm/s in vaporizers 1 and 2, respectively. For both liquid

vaporizers these rates the gravitometer indicated a poorer sampling precision but the calorimeter did not. Figure 5.25 shows the change in precision

of the computed heating value when going to the lower sampling rate. If the

linear flow rate in the sample vaporizer was the important factor in determining sampling precision at low sample rates, the vaporizer 2 results at

9.5 slpm would have been much poorer than actually observed. This suggests

that the poor precision at low sample rates originates at some point in the

sampling system, other than in the vaporizer. It seemed plausible that the

low sample flows could have been too low to provide adequate mixing in the

acculuator. However, this probably was not the case because the accumulator

residence time was 68 s in these tests; good results were obtained during

shipboard tests with residence times of 120 s. However, the shipboard accu- mulator was heated to induce mixing.

Test E

Figure 5.26 shows the deviation in computed heating values for test E; this was a short test to see if the needle valve is necessary in a sampling

system to prevent backflow. In this test the needle valve (valve S2, figure

5.21) was fully open. These results confirmed the laboratory results in

that a needle valve is not necessary, at least when using a tube vaporizer

where there is a finite pressure drop in the vaporizer. (However, the needle

valve is useful for controlling sampling rates.) The pressure difference

between the test section and sample panel varied between 0.5 psi (3 kPa) and

1.5 psi (10 kPa) during this test; when using the needle valve to control

the sample rate the pressure difference was typically 20 psi (0.14 MPa) to

35 psi (0.24 MPa). (No significance should be put on the unusually high

precision of this test; these estimated standard deviations are smaller than

that of analysis alone.)

Test F

Test F was a comparison of electric (vaporizer 3) and steam (vaporizer 1)

vaporizers. Figure 5.27 shows the deviation in computed heating value for

this test. In this test the electric vaporizer had a heat input of 77

watts; at this power level, roughly half of the vaporizer was frostfree and

the outlet temperature was roughly 100°F (38°C) . As expected, the precision

of the steam and electric vaporizers was comparable.

Test G

The last test considered the effect of heat leak on precision. Up to

this point the sample lines had been insulated with fiberglass pipe insulation. During operation the lines felt slightly cool to the touch in most

119
DC

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+-> 03 +J C\J 10

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<o N

+J n- CLE S_ 3 <T3 O > o </) CL

CD n> Q >

LO

CM

S_3

% '3f11VA 9NI1V3H NI N0I1VIA3Q

120
LJJ CD

o

4-

<T3

ro

0)

S- TJ

CU

+-> Q.EO

u

C 4J

•i- to

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o >>

> o

CD (O

CM

CD

s-CD

% '3fllVA 9NI1V3H Nl N0I1VIA3Q

121
CO

LLJ CQ

3

O

C 1

SS_ 4- o4— onCD

to I—

CD Cl 3 E

r— H3 (O to >

QJ

sr o

•r- C

+j ai

ra -o

CD jz o

to T3

a> <a >> — < <u

<a >

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T3 -Q CU

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ai -o .c • c

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122
places; at the 90° bend between the block valve (Valve Si) and needle valve

(Valve S2) there was a frost spot on the line to vaporizer 2 (or 3) . No

frost spots appeared on the sample line to vaporizer 1. For this test, the

insulation was removed from the sample line to vaporizer 1. Samples from

this vaporizer were going to the calorimeter and gravitometer during the

insulation removal. Before all of the insulation had been stripped away the

calorimeter went off scale, indicating a heating value of greater than 1195

3 Btu/scf (44.515 MJ/m ). As figure 5.28 shows, the computed heating values

were significantly higher for the uninsulated sampling system. (The deviations are referenced to the average values obtained in test F.) The sample

analyses indicated a 0.8 mole percent reduction in nitrogen which was statistically significant. Also, there was a 0.3 mole percent increase in the

ethane content; but based on the limited number of samples, this increase

could not be considered statistically significant. This indicates that

backflashing occurred in the sample line and that it enriched the heavy

components in the observed samples.

General Comments

Based on the shipboard tests, we expected frost to accumulate at the

90° bend on the steam vaporizer sample outlet lines at sample rates above 10

slpm. The impingement chamber apparently worked satisfactorily because

there never was any indication of frost at the bend. The sample lines were

felt at and near the bends several times throughout the tests; there was never an indication that the line was cooler at the bend.

Throughout these tests, the comparison between the measured and com- puted heating values was fairly good considering that the fraction

ranged between 0.08 and 0.13 mol percent. An analysis of the heavy fraction

indicated that it had roughly equal parts of Cg's and C^'s. Therefore, the

response factor for C,+ peaks, K~ was computed by

6 C

6 +,

KV

KnC

4

< D„C

6 + °nC7 >/ 2 V4 ».U

where K „ is the measured response factor for normal butane and the D's are

nC^

the response factor reported by Dietz [25]

Except for runs E, F and G (the final day's tests), the agreement

between measured and computed specific gravities was excellent. It is not

known why the final day's results were consistently low by 1.3 to 1.4 percent,

especially since the heating values agreed to 0.14 percent or better.

The estimated standard deviation in the computed liquid densities

listed in table 5.19 is much larger than observed in previous tests. However,

the densities in the flow facility tests reflected both temperature and

composition fluctuations. The temperature fluctuations, which were as large

as 1.5 K, make comparisons based on density meaningless.

123
o

CO

O E <4- ro

CO

I

CO

I CD

i

CNI

I

C O

+-> -o

ro c: Ol ro >> < co CD ro CO >

Dlr—O -t-> r— -O a

ia e cuCL

t_ to

es T3 QJ Sai -£z

4-> 1— 3 n O.E • -a o o rr u

-i-> ai co

+-> +-> rs C >, (1) •i- 4-> N

CO I

S. C T- o

O U Cl •- ro ro +J M— >

ro

•r- 3 E > O O

QJ i— 5- Q <4- 4—

oI

CM

QJ

S-3
Throughout these tests, integrator A had difficulties in reliably

measuring the peak area because the peak had a small peak height and

wide peak width compared to the other peaks (see section 4.3.1.1 for more

details) . Except for the first day integrator B reported consistent C,+

b peak areas. Therefore, the C

g + peak area for integrator A was computed by

assuming that the ratio of the C

g + peak area to that of the normal butane

peak area was equal for both integrators; this ratio for integrator B was constant to within + 2 percent throughout the tests. (A check showed that

the ratios of iso to normal butane peak areas for the two integrators were

equal to within one percent or better.)

During the first two days the two integrators reported comparable

compositions for all components except iso and normal pentane; this difference was traced to calibration problems with integrator B. The typical

spread between the calculated heating values for the two integrators was

0.05 to 0.14 percent; the difference in pentane contents reported by the two

integrators accounted for this heating value difference.

On the third day (Test D) the program in integrator A was altered to

hopefully eliminate the scatter in detecting the Cg+ peak. This change not

only did not improve the peak detection but it caused increased scatter

in integrating the nitrogen and methane peaks. (In this chromatographic

column arrangement, nitrogen and methane eluted after Cg+.) The differences

in computed heating values differed by as much as one percent with integrator A showing the most scatter.

On the last day the integrator A program was identical to the program

used the second day. On this day integrator B gave erratic nitrogen con- tents even though no program changes were made. However, we noted that the

peak width parameter (which was automatically updated after each peak)

varied between 20 and 66 seconds. This variation affected the next (nitrogen) peak area measurement but not the methane peak area measurement. This

is because the typical peak widths for nitrogen and methane were 2 0 and 60 s, respectively. Agreement between the two integrators occurred only when the

updated peak width parameter was between 20 and 30 s.

5.3. Conclusions and Recommendations

This work has systematically considered many factors which could affect

the precision and accuracy of the composition of samples withdrawn from a flowing LNG stream. Laboratory and field tests showed that it is feasible

to obtain and analyze representative samples with a precision (based on three standard deviations) of better than + 0.3 0 percent in the computed

heating value; this includes the gas analysis precision of + 0.06 percent.

The accuracy of the measurement depends only on the gas analysis accuracy;

both laboratory and shipboard tests showed that a properly designed and

operated sampling system produces no statistically significant bias. A

125
comparison of measured and computed heating values during the second flow

facility test verified that the difference between the two values was within

the combined uncertainty of the calorimeter measurement (+ 0.3 percent [30])

and the sampling measurement process.

Table 5.20 summarizes the variables evaluated in the sampling tests and

groups them according to their effect on sampling precision and accuracy.

The test results indicated that heat leak causes backflashing of nitrogen

(and probably methane) which enriches the samples in the heavy (^2+) com- ponents. However, field tests showed that insulating the sample line with

one inch (25 mm) thick layer of fiberglass pipe insulation sealed with duct

tape eliminates the heat leak problem.

Table 5.20. Variables evaluated for their effect on LNG sampling

precision and accuracy.

Variables affecting both sampling precision and accuracy:

• Heat leak to liquid sample line

Variables affecting sampling precision but not accuracy:

• Sampling rate

• Vaporizer design

• Time-averaging the vaporized sample

• Sampling rate transients

• Probe design

Variables not affecting sampling precision and accuracy:

• Temperature and pressure at the sampling point

• Pressure differential between the sampling point pressure and

the equilibrium LNG pressure

• Flow rate past the sampling point

• Pressure drop in the liquid sample line between the sampling

point and vaporizer

• Composition of the liquid being sampled.

Five variables were found to adversely affect sampling precision. Both

laboratory and field tests showed that below a certain sampling rate, the

sampling precision diminishes; this minimum sampling rate varied among

various sampling system designs. A mechanism for the sampling rate's importance is unknown. Attempts to correlate the sampling rate with heat leak,

accumulator residence time, linear flow rate in the liquid sample line and

linear flow rate in the vaporizer failed. However, criteria for setting the

minimum allowable sample rate must be found before general guidelines for

LNG sampling system design can be established. The next section gives

sampling rates for the recommended sampling system design.

126
Laboratory results clearly indicated that a small diameter tube vaporizer was better than a vaporizer with a large cross sectional area. Tests

also, showed that rapid sample vaporization gave the best results. However,

there is no advantage in having the vaporizer outlet temperature above 100 °F

(38°C) . Both steam and electrically heated vaporizers produce comparable

results

The need to time-average the sample stream leaving the vaporizer in an accumulator arises from fractionation during vaporization. The minimum

residence time necessary to obtain precise results depended upon the sampling system; residence times of 20 to 120 s gave good results.

Although the field tests were inconclusive, they indicated that taking

samples within 30 minutes of a major change in sampling rate diminishes

sampling precision. However, minor fluctuations and slow drifts in sampling

rates did not affect the results.

The side tap probe was found to be more reliable than an upstream

facing pitot tube. For unknown reasons the pitot tube occasionally gave

erratic results.

The conclusion that certain variables did not affect sampling error

must be considered valid only over the ranges tested; however, this range

usually included the anticipated operating ranges of on and off-loading of

LNG tankers.

There is no reason to expect the temperature and pressure to affect

sampling error provided the conditions are far from the critical point of

the LNG.

At some low value the difference between the pressure of the sampled

liquid and the saturation pressure of the LNG (i.e., subcooling) in combination with heat leak should create premature vaporization which could adversely

affect sampling precision; however, this effect was not detected at pressure

differentials as low as 3.9 psi (25 kPa) (this corresponds to ^ 0.5 K subcooling) . LNG flow rates corresponding to Reynold's numbers ranging between 1500

and 50,000 did not affect sampling precision; it is unlikely that there

would be any adverse effect on precision at the higher Reynold's numbers

anticipated in on and off loading operations.

The fact that a pressure drop in the liquid sample line which is com- parable to the pressure drop in the vaporizer is unnecessary eliminates the

need for a liquid flow control valve. However, this conclusion is known to

be valid only when using a tube vaporizer.

Finally, there is no problem in sampling LNG mixtures which contain up

to 0.15 percent C

5 +. The heavies would be a problem if they raised the

sample dew point temperature to near ambient temperature.

127
5.3.1. Recommended LNG Sampling System Design and Operating Criteria

Based on the laboratory and field test results, the following sampling

system design criteria are recommended:

Probe - side tap mounted horizontally with the probe flush with the

wall of the LNG pipe; probe inner diameter should be as small as feasible

(< 0.25 inch (6. 4 mm) )

Liquid phase needle valve - optional, but useful for flow control.

Liquid sample line - use as small a bore tubing as feasible (< 0.20

inch (5.1 mm)) and make the line as short as possible. (A filter is recom- mended to prevent line plugging.)

Sample vaporizer - use a coiled tube vaporizer with the tube inner

diameter comparable to the sample line tubing. If steam is the vaporizing

medium, use the design procedure outlined in section 5.2.2 with an impingement chamber. Electrically heated vaporizers can be designed using the same procedure as steam vaporizers; however, thin walled tubing is necessary to

minimize the necessary amperage. Also, a thermostatic control is necessary

to prevent the vaporizer from overheating if the sample flow rate decreases.

Accumulator - size for a residence time of at least 45 s; the length

to diameter ratio of the accumulator should be greater than 1.5. The sample

inlet line should extend to near the bottom of the vessel but the outlet

line should not penetrate the vessel volume. Heating the bottom of the

accumulator may produce improved mixing.

Insulation - the probe and liquid sample line should be insulated

sufficiently to prevent moisture from condensing on the lines.

The following sample system operating conditions are within the range of

values found to give good results in the field tests and therefore are recom- mended : Sampling rate - greater than 20 slpm; this criteria applies only to

the recommended sampling system.

Sample pressure - preferrably greater than 20 psig (0.24 MPa) to provide

sufficient gas sample for purging and replicate analyses from a 500 cm^

sample cylinder.

Vaporizer outlet temperature - 80 to 100°F (27 to 38°C)

The shipboard tests and flow facility test 2 sampling systems both

worked satisfactorily and may be considered proven sampling systems.

5.3.2. Recommendations for Future Work

All tests clearly indicated that sampling rate is an important operating variable but no criteria for establishing the minimum acceptable rate

were found. The existing test results need to be carefully reexamined for

clues to understanding how sampling rate affects sampling precision. Hopefully,

this would provide the answer, or would at least suggest future tests.

At this point, the need for time averaging denotes the lack of understanding of the sample vaporization process. Different vaporizer designs

128
should be tested with the goal of understanding the vaporization process and

eliminating the need for an accumulator, if possible. (These tests probably

would provide some insight into the sample rate problem too.)

Resolving the uncertainties associated with the sampling rate and

vaporizer design will likely allow establishment of general design and

operating criteria. At this point a standard procedure should be developed

for continuously sampling LNG from flowing streams.

Other types of LNG sampling techniques need to be studied. There

should be additional work on systems for batch sampling LNG, e.g., Cook

sampler. Also, reliable systems for sampling LNG from tanks need to be

developed

The goal of all future work should be to establish the basis for standard LNG sampling procedures which have an uncertainty comparable to that

obtained from gas analysis alone.

129
6.0 REFERENCES

1. Caldwell, B. J., Fuel Gas Energy Metering, Transmission Measurement Committee Report Number 5 (revised) , page 55 (1976) , American Gas Association, Inc., Arlington, VA.

2. Armstrong, G. T. , E. S. Domalski and J. I. Minor, Standard combustion

data for the fuel gas industry, American Gas Association 1972 Operating

Section Proceedings, page D-72 (1972).

3. McCarty, R. D. , A comparison of mathematical models for the prediction

of LNG densities, Nat. Bur. Stand. (U.S.) Internal Report, NBSIR 77-867

(Oct. 1977).

4. Hiza, M. J., An empirical excess volume model for estimating liquefied

natural gas densities, submitted to Journal of Fluid Phase Equilibria

(1977).

5. Natrella, M. G. , Experimental Statistics, Handbook 91, National Bureau

of Standards (1963) .

6. "Standard Method for Analysis of Natural Gas by Gas Chromatography,"

ASTM Designation: D1945-64 (Reapproved 1973)

7. "Standard Method for Analysis of Natural Gases and Related Types of Gaseous Mixtures by the Mass Spectrometer," ASTM Designation: D1137-53.

8. Dalmaze, M. R. , LNG sampling technique, Gaz Aujourdhui 9_6, 448 (Nov. 1972).

9. Trigo, J., System samples LNG accurately, Hydrocarbon Proc. p. 8 3 (April

1976) .

10. The Cosmodyne Corporation, Cryogenic Sampler Bulletin TDS-8064, Torrance,

Calif.

11. Cook, H. L. , Method and apparatus for sampling refrigerated volatile

liquids, U.S. Patent No. 3,487,692 (Jan. 1970).

12. Miller, A. J., Techniques for sampling natural gas, SNG, and LNG, Pipe

Line Industry 39. (3), 70 (Sept. 1973).

13. "Standard Method of Sampling Natural Gas," ASTM Designation: D1145-53.

14. Chapman, J. A. and G. D. Payne, Sampling system guidelines, paper presented at the 19th Annual ISA Analysis Instrumentation Symp. , April 24-

26, 1973, St. Louis, MO.

15. Turbett, J. R. , Rockwell International, Atomics International Division,

Golden, CO (private communication, 1977).

16. Conn, A. P., Transco, Houston, TX (private communication, 1976).

17. Method of Analysis for Natural Gas and Similar Gaseous Mixtures by Gas

Chromatography, GPA Publication 2261-72, Gas Processors Association,

Tulsa, OK.

18. Thompson, B. , Fundamentals of Gas Analysis by Gas Chromatography, Varian

Associates, Inc., Palo Alto, CA (1977).

130
19. Purcell, J. E. and C. P. Gilson, Improved Analysis of Natural Gas,

Chromatography Newsletter 1 (2) , 45 (Nov. 1972) , published by PerkinElmer Corp., Norwalk, CT.

20. Lawson, A. E. , A versatile, low cost gas chromatograph, American

Laboratory (May 1969).

21. Ludtke, P. R. , Performance characteristics of a liquid helium pump, Nat.

Bur. Stand. (U.S.) Internal Report, NBSIR 75-816 (July 1975).

22. Cook. H. L . , Transco, Houston, TX (private communication, 1977).

23. Handbook of Chemistry and Physics, 45th Ed., p. D86, The Chemical Rubber

Co., Cleveland, OH.

24. Childs, G. E., L. J. Ericks, and R. L. Powell, Thermal conductivity of

solids at room temperature and below, Nat. Bur. Stand. (U.S.) Monograph

131, p. 257 (Sept. 1973)

25. Dietz, W. A., Response Factors for Gas Chromatographic Analyses, J. of

Gas Chromatograph, p. 68 (Feb. 1967)

26. Mann, D. B., Cryogenic flowmetering research at NBS, Cryogenics 11 , 179

(1971)

27. Brennan, J. A., Cryogenics Division, National Bureau of Standards, Boulder,

CO (private communication, 1976).

28. Goodwin, R. D., The thermophysical properties of methane from 90 to 500 K

at pressure to 700 bar, Nat. Bur. Stand. (U.S.) Technical Note 653 (April

1974)

29. Hanley, H. J. M. , W. M. Haynes, and R. D. McCarty, The viscosity and thermal • conductivity coefficients for dense gaseous and liquid methane, J. of Phys.

and Chem. Ref. Data 6 (2), 597 (1977).

30. "Standard Method of Test for Calorific Value of Gases in Natural Gas Range

by Continuous Recording Calorimater , " ASTM Designation: D1145-53. *

31. Hiza, M. J., W. M. Haynes and W. R. Parrish, Orthobaric liquid densities

and excess volumes for binary mixtures of low molar-mass alkanes and

nitrogen between 105 and 140 K, J. Chem. Thermodynamics 9_, 873 (1977).

131
APPENDIX 7.1. GAS ANALYSIS DATA

This appendix lists the compositions and computed ideal gas heating

values obtained during the evaluation of gas analysis techniques. The

heating values were computed using the values listed in table 2.2. To

3 convert from MJ/m to BTU/SCF multiply by 26.845. Unless stated otherwise,

all peak areas were measured using integrator A. Mix in these tables refers

to the prepared mixtures listed in table 4.2.

7.1.1. Comparison Between Mass Spectrometry and Gas Chromatography.

Table 7.1.1 lists the mass spectrometry analyses obtained from a local

laboratory. The table lists the reported duplicate analyses on each sample.

Table 7.1.2 lists the gas chromatograph analyses obtained using the two

column configuration.

132
Table 7.1.1. Results of mass spectrometer analyses.

Composition, mol %

ID Mix N

2 CH

4

C

2 H

6

C

3 H 8

441

441

445

445

442

B

B

BB

A

5.62

3.42

1.81

5.23

8.53

84.42

86.61

87.55

84.89

76.72

8.34

8.61

8.49

8.38

4.21

.35

0.00

.98

.25

5.97

442

444

444

443

443

AA

AD

0

6.91

8.45

7.58

1.16

1.49

78.49

76.69

77.57

84.03

83.12

4.73

4.22

4.25

4.93

4.71

4.92

6.24

6.14

5.74

6.59

446

446

501

501

503

0

D

B

BB

7.09

5.23

2.35

1 .50

1.83

78.22

79.86

87.77

88.20

88.13

4.43

4.37

8.48

8.95

8.59

6.19

6.64

0.00

0.00

.14

503

502

502

504

504

B

D0

DD

1.68

1.32

1 .23

1.69

1.23

88.12

82.53

83.01

82.76

83.32

8.82

4.12

4.46

4.63

4.52

0.00

7.73

7.00

6.62

6.62

505

505

5u6

506

C

C

CC

3.33

1.03

4.22

1.21

88.24

90.55

87.15

90.53

6.30

6.53

6.07

6.67

1.35

1.04

1.84

.67

Heating

Value

iC 4H 10 nC

4

H 10 MJ/m

.70 .56 39.207

.80 .55 39. 994

.62 .55 40.966

.DO C

. b6

2.59 1.99 42.980

2.93 2.01 43.358

2.45 1.95 42.918

2.47 1.99 43.250

1 Q J.9o AC 1 D A .04 4.06 45.528

.09 3.98 43.189

.01 3.88 43.985

.84 .56 40.391

• 82 • 53 40 • 31

.74 .56 40.523

.82 .56 40.732

.07 4,23 46.339

.08 4.23 46.059

.03 4.28 45.726

.02 4.30 45.371

.57 .21 39.549

.65 .20 40.466

.50 .22 39.473

.71 .21 40.285
Table 7.1.2. Results of gas chromatographic analyses.

Composition, mol t

tied L l liy Date Mix Value

N 2 LH

4 C„H,

2 6 3 8 iC

4

H 10

nC

4

H 103 Mnu/1 /mIII 9/ 8 B 1.352 88.111 8.408 .958 .485 .686 41.098

9/ 8 1 .349 88. 141 8.401 .954 .477 • 678 tliVOI

9/ 8 A 4.330 81 .301 4.765 4.803 2.401 2.400 44.153

9/10 B 1 .423 88.043 8.389 .980 .475 .690 41 .073

9/10 B 1 .260 88.204 o « h Uo .474 .680 41.127

9/13 R 1 .305 88.106 8.422 .991 .485 .691 41 . 142

9/13 B 1.296 88.116 8.^17 .991 .485 .696 41 .148

9/13 C ,66b 90.514 6.041 2.170 .307 .302 40.896

9/13 C .552 90.654 6.022 2.157 .306 .309 40.931

9/13 B 1 .331 88. 109 8.394 .985 .490 .691 41.125

9/13 B 1.33b 88.094 8.399 .999 .485 .687 41.f25

9/14 B 1.291 88.199 8.379 .978 .476 .677 41 .109

9/14 B 1.297 88.189 8.379 .972 .476 .687 41.112

' ' i ** D 1 .341 88.163 8.359 .9/6 .* 4ft1 HO J • o * o 41 (1Q0 9/14 A 4.503 80.947 4.736 4.921 2.432 2.462 44.224

9/14 A 4.159 81.465 4.745 4.872 2.385 2.375 44.216

9/14 A 4.05b 81.507 4.756 4.899 2.393 2.390 44.293

3/14 A 4.042 Rl .600 4.727 4.872 2.381 2.378 44 • 255

9/14 A 4.031 81.564 4.734 4.889 2.391 2.390 44.289

9/14 B 1 .255 88.241 8.383 .971 .475 .675 41.117

9/29 B 1.357 88.182 8.344 .971 .477 .668 41.064

9/29 q 1 .347 88. 103 8.403 .978 .491 .678 41.108

9/29 D .009 85.342 5.086 4.873 0.000 4.690 45.828

9/29 D .008 85.449 5.064 4.855 0.000 4.624 45.756

9/29 0 .008 85.386 5.065 4.872 0.000 4.670 45.804

9/29 Q .009 85.369 5.075 4.861 0.000 4.686 45.81

9/29 c .644 90.505 6.033 2.191 .304 .323 40.929

9/29 c .618 90.580 6.048 2.154 .295 .305 40.899

9/29 c .681 90.562 6.020 2. 143 .297 .297 40.857

10/ 1 1 .382 85.887 8.504 2.990 .527 .710 42.31

10/ 1 c .625 90.526 6.061 2.163 .310 .315 40.926

10/ 1 c .626 90.562 6.044 2.155 .305 .308 40.907

10/ 1 c .623 90.561 6.046 2.154 .306 .310 40.910

10/ 1 c .620 90.538 6.066 2.164 .306 .306 40.919

10/ 1 0 .011 85.277 5.108 4.878 0.000 4.727 45.867

10/ 1 0 .008 85.166 5.104 4.897 0.000 4.826 45.961

10/ 1 0 .009 85.285 5.082 4.877 0.000 4.748 45.877

10/ 1 0 .008 85.291 5.086 4.877 0.000 4.738 45.871

10/ 1 E 1.375 85.877 8.495 3.010 .519 .724 42.329

10/ 4 1.391 85.993 8.432 2.956 .519 .709 42.263
Table 7.1.2. (Continued)

Mix Composition, mol % Heatn ng

Val ue Date N 2 CH 4 C 2H 6 C 3 H 8 iC 4H 10

nC 4 K1Q MJ/m 3

10/ 4 C .645 90.525 6.043 2.168 .305 .315 ^0.912

10/ 4 C .631 90.563 6.042 2.159 .299 .306 <*0.900 10/ * c .632 90.571 6.034 2.153 .301 .309 ^0.898

10/ 4 c .639 90.541 6.056 2.158 .301 .305 40.901
7.1.2. Statistical evaluation of gas chromatographic analyses.

Table 7.1.3 lists the data taken to determine the accuracy and precision of gas chromatographic analyses using the two column configuration.

The first digit of the analysis number refers to the day while the remaining

digits refer to the sequence number. In this table, mixtures A, B, C and D

correspond to mixtures E, F, G and C in table 4.2. Table 7. 1.3. A lists the

outlying analyses which were not included in the statistical evaluation.

Table 7.1.4 gives the results of repetitive analyses of mixture E which were

made after the integrator was repaired (see section 4.2.).

136
Table 7.1.3. Raw data for determining the precision and accuracy of gas chromatographic analyses.

nalysis Composition, mol % Heati ng Number Operator Mix

No

L CH„ r H C,H„

3 8

1 C a H i r\ 4 10 nC.H1n

Val ue

3 MJ/m 101 2 0 .615 90.585 6.031 2. 152 .308 . 309 40.909

102 1 c 10.969 65.875 16.249 5.436 .496 .976 42 .468

103 2 3 .974 88.224 7.257 2.560 .491 . 494 41 .660

104 1 A 1 .383 85.921 8.480 2.978 .523 .715 42.300

105 2 C 10.980 65.878 1 6 .240 5.439 .491 .973 42.457

106 c 1 TOA. O D • 7 1 (J 8.487 2.980 . bc4 7 1 cr 107 1 B .971 88.196 7.270 2.570 .495 . 499 41 .677

108 1 D .614 90.585 6.040 2.150 .303 . 309 40.906

109 2 D .614 90.562 6 .054 2 . 156 .305 .310 40.916

110 1 rU 10. 966 65.802 16.306 5.463 .500 .963 42.493

111 1 A 1 .383 85.905 8.495 2.980 .526 .711 42.304

112 2 B .970 88.219 7.260 2.572 .491 . '488 41 .664

113 2 A 1.385 85.893 8 .484 2.988 .526 .724 42.316

114 1 9 • 971 88.216 7.262 2.568 .493 .491 41 .666

115 1 0 .613 90.589 6.037 2.154 .301 .306 40.904

116 2 c 10.980 65.839 16.280 5.444 .493 .965 42.466

117 1 A 1 .380 85.931 8.468 2.995 .519 . 707 42.297

118 1 L 10. 969 o t> • a 1 b 16.249 5.439 • 495 . y 1 2 42 .466

119 2 D .614 90.581 6.039 2.153 .299 .314 40.909

120 2 B .971 88.194 7.277 2.568 .497 .493 41.675

121 2 C 10.964 65.791 16.313 5.466 .495 .970 42.500

122 c

AA QF Q O 1 BD • 9e

8.491 2.978 • 514 7 1 O • fid 4£ • 123 1 0 .614 90.589 6.019 2.164 .303 .311 40.910

124 1 s .971 88.206 7.271 2.564 .495 .493 41 .669

201 1 A 1.381 85.919 8 .494 2.976 .522 . 708 42.297

202 2

Q .971 Ho • 1 9

j

7.270 2.582 . 496 • 48 8 4 1 . 0 1 0 203 1 c 10.960 65.883 16.261 5.432 .499 .965 42.466

204 2 D .614 90.561 6.043 2.157 .312 .313 40.922

205 2 A 1 .382 85.918 8.488 2.981 .524 . 707 42.298

206 2 C 1 0 .970 65.842 16.280 5.449 • 497 • 961 42.473

207 1 0 .615 90.572 6.050 2.156 .304 .303 40.908

208 1 B .969 88.197 7.272 2.562 .498 .502 41 .679

209 1 A 1.382 85.915 8.497 2.977 .523 .706 42.297

210 2 0 .614 90.547 6.066 2.166 .302 .305 40.919

211 1 c 10.969 65.832 16.288 5.442 .498 .971 42.481

212 2 8 .971 88.213 7.270 2.568 .492 .466 41 .663

213 2 C 10.971 65.855 16.281 5.444 .492 . 956 42.462

214 2 A 1.384 85.909 8.481 2.993 .522 .711 42.304

215 1 D .614 90.594 6.036 2.149 .302 .306 40.901

216 1 B .969 88.203 7.273 2.564 .497 .'494 41.673
Table 7.1 .3. (Continued)

Analysis

Number

217

218

219

220

221

222

223

224

301

302

303

304

305

306

307

308

309

310

311

312

313

314

315

316

317

318

319

320

321

322

323

324

401

402

<*03

t*V<*

Operator Mix Composition, mol %

N

2 .614

1.382

10.969

.971

10.970

.972

1 .382

.613

.614

.972

10.956

1 .385

10.989

.971

.615

1.383

.972

10.962

.613

1 .381

1 .383

.971

.614

10.980

.614

.969

1.384

10.970

.617

1.383

10.965

.971

.968

10.980

1.383

.616

CH

4 90.566

85.926

65.817

88.199

65.841

88.200

85.919

90.573

90.593

88.195

65.740

85.919

65.815

88.168

90.565

85.888

88.183

65.775

90.557

85.893

85.870

88.170

90.555

65.823

90.565

88.175

85.877

65.850

90.565

85.931

65.837

88.172

88.217

65.849

85.915

90.589

C

2 H

6 6.058

8.480

16.309

7.270

16.270

7.262

8.494

6.037

6.032

7.279

16.360

8.494

16.289

7.304

6.049

8.506

7.290

16.339

6.052

8.504

8.527

7.298

6.053

16.281

6.053

7.297

8.509

16.280

6.052

8.479

16.274

7.294

7.264

16.250

8.484

6.024

C

3 H 8 2.150

2.981

5.444

2.573

5.459

2.578

2.975

2.165

2.155

2.562

5.480

2.980

5.453

2.569

2.154

2.983

2.573

5.453

2.165

2.984

2.988

2.570

2.170

5.452

2.156

2.570

2.984

5.438

2.152

2.982

5.461

2.577

2.564

5.459

2.986

2.166

1C

4

H 10 .307

.523

.496

.491

.497

.494

.521

.303

.304

.497

.497

.517

.490

.497

.307

.525

.492

.504

.304

.521

.523

.497

.303

.498

.300

.497

.525

.502

.306

.521

.497

.498

.490

.500

.523

.303

nC

4

H 1Q

.305

. 709

.964

.!»96

.963

. <»94

. 709

.310

.303

. <»96 .967

.705

.965

.*9l

.311

.715

.^90

.967

.309

.717

.709

. '+<)<* .306

.966

.312

.'93

.721

.960

.308

. 704

.966

. '+88

.V97

.963

. 709

.302

Heating Value

MJ/m 3 40.911

42.297

42.480

41.673

42.477

41.674

42.296

40.915

40.903

41.674

42.523

42.291

42.467

41.681

40.916

42.312

41.674

42.505

40.919

42.311

42.31^

41.683

40.919

42.47b

40.913

41.682

42.318

42.470

40.911

42.291

42.483

41 .681

41 .668

42.470

42.301

40.904
Table 7.1.3. (Continued)

Analysis _ . Ml- Composition, mol % Heating Number Operat0r "

1X rH

Value

N

2 CH4 C

2 H

6

C

3

H 8

iC

4

H 10

nC

4

H 1Q MJ/m

3

405 1 3 » 9 71 88.206 7.272 2.568 .495 .'-»89 41.66tJ 406 2 A 1.383 85.929 8.464 2.978 .532 .714 42.J02

407 2 C 10.979 65.863 16.248 5.433 .496 .980 42.466

408 1 0 .614 90.571 6.039 2.155 .306 .315 40.917

409 2 3 .970 88.186 7.264 2.568 .505 .507 41.690

^10 1 C 10.965 65.794 16.264 5.496 .505 .976 42.516

411 1 A 1.383 85.894 8.487 2.982 .530 .724 42.318

412 2 0 .614 90.562 6.042 2.167 .303 .312 40.919

413 2 A 1.383 85.924 8.471 2.988 .524 .710 42.300

414 1 0 .613 90.568 6.044 2.155 .306 .314 40.917

415 1 3 .971 88.204 7.265 2.571 .496 . '-»92 41.672

416 2 C 10.976 65.868 16.245 5.447 .495 .969 42.464

417 2 6 .971 88.185 7.270 2.591 .495 41.680

418 2 0 .615 90.583 6.036 2.153 .306 .308 40.908

419 1 C 10.979 65.846 16.249 5.453 .504 .969 42.475

420 1 A 1.383 85.905 8.498 2.984 .523 .707 42.302

421 1 3 .972 88.200 7.268 2.568 .495 .497 41.674

422 2 A 1.382 85.927 8.^74 2.982 .526 .710 42.299

423 2 C 10.981 65.866 16.231 5.457 .503 .961 42.464

424 1 0 .615 90.577 6.042 2.156 .302 .308 40.908
Table 7. 1.3. A. Outlier analyses not used in statistical evaluation.

tlber* OP^tor Mix Co.po.1t1on.wlX

N

2 CH

4

C

2 H

6

C

3 H 8

iC

4

H 10

nC

4

H 10 MJ/m3 42.296

41 .024

42.631

42.613

41 .671

40.98<t 40.954

42.565

41 .693

42.749

42.623

40.909

42.524

42.297

42.908

42.650

41.667

42.414

41.691

42.299

104 1 A 1 .393 65.912 8.479 2.978 .523 .715

109 2 0 .328 90.846 6.055 2. 156 . 305 .310

110 1 c 10.620 66.129 16. 320 5.468 .500 .964

121 2 c 10.690 66.041 16.330 5.472 .496 .971

202 2 d .982 88.183 7.269 2.582 .496 . 488

210 2 D .4<44 90.715 6.068 2.167 .302 . 305

217 2 C .502 90.677 6.059 2.150 .307 .305

219 1 c 10. 760 66.01

16. 320 5.448 .496 . 965

220 2 3 .918 88.253 7.269 2.573 .491 . 496

303 1 C 1 0.400 66.252 16.390 5.490 .498 . 969

310 1 c 10.680 66.028 16.360 5.460 .505 .968

317 2 0 .628 90.550 6.054 2.156 .300 .312

323 2 c 10.880 65.900 16.290 5.466 .497 .967

403 1 A 1 .392 85.907 8.483 2.986 .523 .709

410 1 c 10.060 66.527 16.^29 5.501 .506 .977

411 1 A .594 86.591 8.547 3.014 .530 .724

415 1 B .983 88.19<» 7.264 2.571 .496 .492

416 2 C 10.999 66.006 16.069 5.459 .496 .971

417 2 3 .9^5 88.208 7.272 2.592 .495 .488

420 1 A 1 .390 85.899 8.497 2.984 .523 . 707
Table 7.1.4. Raw data for determining the accuracy and precision of gas chromatographic analysis taken after integrator repair.

Analysis Time N, Number 101 1117 1.383

102 1 133 1 .382

103 1 149 1 .382

1 0* 1204 1 .383

105 1219 1.381

106 1234 1.384

107 1250 1 .383

108 1305 1.383

109 1321 1 .378

110 1336 1.381

111 1351 1 .381

112 1407 1 .383

113 1422 1 .383

114 1437 1 .382

115 1452 1.383

116 1507 1.381

117 1522 1.384

118 1538 1.380

119 1553 1 .379

120 1608 1.383

121 1623 1 .378

122 1639 1.378

201 1102 1.382

202 1117 1 .381

203 1133 1.382

20* 1 148 1.385

205 1204 1.378

206 1219 1 .387

207 1234 1 .386

208 1350 1.386

209 1306 1 .385

210 1331 1.386

211 1336 1.383

212 1352 1.384

213 1407 1.385

214 1422 1.384

215 1438 1.384

216 1453 1 .385

217 1508 1.385

218 1524 1.383

219 1539 1 .384

220 1554 1.384

221 1609 1.383

222 1624 1.384

Composition, mol % CH A 2 6 3 8 85.925 8.*77 2.982

85.933 8.479 2.980

85.90* 8.487 2.989

85^913 8.476 2.998

85.903 8.504 2.976

85.907 8.501 2.977

85.908 8.492 2.979

85.939 8.469 2.980

85.960 8.458 2.971

85.9*1 8.*70 2.976

85.927 8.*85 2.975

85.918 8.*93 2.979

85.930 8.475 2.981

85.910 8.*93 2.983

85.915 8.*88 2.980

85.927 8.*82 2.983

85.935 8.*76 2.974

85.936 8.*78 2.976

85.923 8.*89 2.978

85.935 8.473 2.975

85.9*3 8.*83 2.973

85.923 8.489 2.977

85.907 8.*96 2.985

85.938 8.*7* 2.979

85.922 8.*87 2.975

85.900 8.507 2.978

85.967 8.*63 2.966

85.910 8.500 2.974

85.91

1

8.*90 2.984

85.902 8.503 2.980

85.901 8.*98 2.982

85.905 8.508 2.977

85.905 8.500 2.984

85.892 8.507 2.989

85.913 8.*90 2.982

85.913 8.*88 2.982

85.885 8.513 2.981

85.906 8.500 2.979

85.887 8.500 2.997

85.886 8.520 2.980

85.911 8.498 2.978

85.902 8.499 2.986

85.890 8.514 2.982

85.908 8.494 2.982

Heating Value

C

4 K 10

nC

4

H 10 MJ/m 3

.526 .707 *2.297

.521 .705 *2.291

.527 .711 *2.308

.523 .707 *2.303

.522 .71* *2.305

.521 .710 *2.299

.522 .716 *2.30*

.521 .708 *2.290

.521 .712 *2.287

.521 .711 *2.292

.52* .709 *2.296

.521 .706 *2.295

.521 .710 *2.29*

.522 .710 *2.302

.525 .709 *2.300

.522 .705 *2.295

.52* .707 *2.290

.522 .709 *2.293

.520 .711 *2.298

.523 .711 *2.293

.520 .703 42.287

.52* .709 42.300

.522 .709 42.303

.522 .706 42.291

.521 .713 42.297

.520 .710 42.300

.520 .706 42.280

.519 .710 42.294

.522 .707 42.298

.521 .708 42.299

.520 .71* 42.303

.521 .703 42.294

.520 .708 42.301

.521 .707 42.305

.520 .710 42.297

.523 .710 42.300

.52* .713 42.310

.52* .707 42.299

.52* .708 42.310

.521 .711 42.307

.523 .706 42.297

.523 .706 42.302

.523 .706 42.306

.522 .710 42.301
7.1.3. Evaluation of gas chromatograph column configuration and digital

integrator

Table 7.1.5 lists the data used in the evaluation of column configuration A; table 7.1.6 gives comparable data for column configuration B. Table

7.1.7 compares the two integrators. All of these tests used prepared mixture H .

142
Table 7.1.5. Column configuration A evaluation data.

Date N

2 CH

4

C

2 H6

C

3 H 3 8/1/77

8/1/77

8/1/77

8/1/77

8/1/77

.603

.598

.599

.593

.599

90.123

90.108

90.112

90. 1 08

90.U5

6.527

6.540

6.537

6.543

6.541

2.197

2.203

2.200

2.20*

2.194

8/1/77

8/1/77

8/1/77

8/ 1/77

8/1/77

.597

.597

.600

.594

.599

90.104

90.118

90.109

90. 1 09

90.102

6.543

6.545

6.544

6.549

6.547

2.203

2.191

2.196

2. 195

2.198

8/1/77

8/1/77

8/2/77

8/2/77

8/2/77

.597

.593

.593

.602

.601

90.117

90.119

90.114

90.104

90.119

6.544

6.542

6.540

6.536

6.536

2.192

2.195

2.201

2.207

2.193

8/2/77

8/2/77

8/2/77

8/2/77

8/2/77

.601

.602

.602

.603

.610

90.115

90.101

90.11^

90.129

90.106

6.539

6.542

6.539

6.532

6.534

2.193

2.204

2.195

2. 192

2.193

8/2/77

8/2/77

8/2/77

8/2/77

9/2/77

.606

.604

.602

.611

.615

90.099

90.102

90.098

90.030

90.090

6.542

6.542

6.546

6.609

6.547

2.202

2.201

2.200

2.201

2.196

8/2/77

8/2/77

8/2/77

.621

.604

.606

90.111

90.138

90.079

6.548

6.545

6.558

2.167

2.165

2.204

tion, mol % Heati ng Value

ic

4

H 10

nC

4

H 10iC

5 H 12

nC

5 H ]2 MJ/m 3

.291 .238 .009 .013 41.030

.291 .239 .010 .011 41.039

.292 .239 .010 .012 41 .037

.290 .239 .010 .012 41.0*3

.291 .238 .011 .011 41 .03*

.292 .239 .010 .012 41 .0*1

.292 .236 .010 .012 41.033

.291 .238 .010 .012 *1.036

.291 .239 .010 .013 *1.0*1

.291 .239 .010 .013 41.0*0

.291 .238 .010 .012 41.03*

.291 .240 .010 .011 *1.037

.292 .239 .009 .012 *1.0*1

.291 .238 .010 .011 41.038

.291 .239 .011 .011 41.030

.291 .238 .010 .012 41.032

.291 .238 .010 .012 41.039

.291 .238 .010 .012 41 . 032

.288 .235 .009 .011 41.022

.291 .238 .013 .013 41.033

.291 .238 .010 .012 41.036

.290 .238 .010 .012 41.036

.291 .2*0 .010 .013 *1.0*0

.291 .238 .010 .010 41 .050

.291 .240 .010 .011 41.032

.291 .241 .010 .012 41. 01*

.290 .237 .010 .011 41.01*

.291 .240 .010 .012 41 .0*2
Table 7.1.6. Column configuration B evaluation data.

Comoosition, mol % Heating

Val ue

riA ua toL c NN

2 CH

4

C H C H i c H nL

4

H 10

if u nL

5 H 12

0 MJ/m

9/ 1 7/77 • o^O 90 .108 O • * / O Pa p All • 0 1 0 ** 1 • 0 J9

9/ 1 7/77 90 • UUU • C 7 J • C O D

A A O • 0 1 c 41 . 1 1)8 9/17/77 .580 90.098 6.530 2.196 .291 .283 .008 .012 41 .076

9/17/77 .583 90.023 6.586 2.212 .292 .284 .008 .012 41.101

9 / 19/77 .592 90.080 6.53^ 2. 199 .291 .283 .010 .012 41 .075

9/19/77 .594 90.046 6.556 2.207 .292 .284 .010 .011 41 .086

9/19/77 .610 90.082 6.520 2.192 .291 .283 .010 .011 41 .060

9/19/77 .591 90.034 6.572 2.206 .292 .284 .010 .012 41 .092

9/19/77 .595 90.031 6.560 2.214 .292 .285 .010 .012 41 .093

9/19/77 .591 90.059 6.553 2.201 .290 .284 .010 .013 41 .083

9/19/77 .592 90.052 6.555 2.203 .292 .283 .010 .013 41 .085
Table 7.1.7. Data for the comparison between integrators A and B.

Composition, mol % Integrator N"2 CH

4

C

2 H6 C3 H

S ic4

H 10nC

4

H 1QiC

5 H 12 nC

5 H 12 MJ/m 3

A .59tt 90.107 6.535 2.212 .291 .236 .011 .010 41 .0<»0 B .595 90.107 6.54<f 2.204 .292 .2<f0 .010 .010 41 .041

A .607 90.109 6.539 2.197 .291 .236 .010 .011 41 .029

B .610 90.090 6.54<» 2.205 .290 .238 .011 .012 41 .037

A .599 90. 110 6.539 2.201 .291 .239 .010 .011 41 .037

B .592 90.122 6.533 2.199 .292 .239 .010 .012 41 .039

A .620 90.09B 6.536 2.199 .291 .236 .010 .011 41 .024

• OCX 90 . 099 6.531 c . c v vj .290 . 238 .009 .012 41. 024

A • 6090.105 6.539 2.206 .292 .235 .011 .011 41 . 037

B .597 90.118 6.533 2.201 .290 .239 .012 .012 41.038

A .619 90.090 6.542 2.199 .292 .238 .010 .011 41 .029

B .620 90.077 6.546 2.201 .292 .2M .012 .011 41 .037

A .607 90.108 6.534 2.202 .291 .237 .010 .011 41.032

B .605 90.121 6.524 2.201 .289 .239 .011 .010 41.029

A .604 90.099 6.538 2.206 .292 .237 .013 .010 41.039

B .616 90.078 6.542 2.206 .289 .241 .014 .014 41 .042

A .601 90.108 6.533 2.208 .292 .237 .010 .011 41 .038

B .605 90.107 6.532 2.208 .290 .237 .009 .011 41 .033

A .602 90.104 6.542 2.202 .292 .237 .010 .012 41 .038

B .610 90.099 6.539 2.202 .290 .236 .011 .013 41.034

A .603 90.098 6.541 2.205 .293 .238 .010 .012 41 .040

B .609 90.108 6.523 2.204 .289 .240 .013 .014 41 .036
7.1.4. Determination of the effect of operating variables on gas chromatograph analysis accuracy and precision.

Table 7.1.3 lists the data for various sample pressures; table 7.1.9

lists the data for different carrier gas flow rates. Prepared mixture H was used throughout these tests.

146
Table 7.1.8. Data for determining the effect of sample pressure on gas chromatograph analysis accuracy and precision.

Samp! e Pressure

kPa9*

9*

9<* 94

94

9494

9<» 949*

94

94

145

145

145

145

1*5

145

145

145

145

145

59

59

59

59

59

59

59

59

59

59

Integrator N

A .594

B .597

A • 598

D . DUO

AA

B .594

AM • 373

Qo fifth. AD

A .592

QD • Do9

AA LAC • OU3

o . ou i

AA . DOd

B .605

A .606

B .601

A • 608

B • 606

A .605

b • t>02

AA

B .618

A .592

B .607

A .590

B .607

A .592

B .589

A .601

B .616

CH

4

C

2 H5 90.073 6.534

90.062 6.543

90.065 6.529

90.066 6.535

90.069 6.537

90.071 6.534

90.070 6.533

90.065 6.540

90.066 6.539

90.057 6.554

90.067 6.538

90.067 6.547

89.930 6.621

89.951 6.624

89.953 6.619

89.949 6.617

89.940 6.620

89.942 6.629

89.943 6.619

89.940 6.623

89.944 6.624

89.942 6.628

90.159 6.480

90.121 6.489

90.164 6.473

90.142 6.483

90.173 6.471

90.147 6.482

90.169 6.467

90.162 6.480

90.152 6.470

90.139 6.476

Composition, mol

C

3

M R iC

4

H 10 2.204 .291

2.201 .292

2.214 .290

2.201 .289

2.200 .291

2.201 .293

2.208 .290

2 . 1 98 . 289

2.202 .290

2.194 .293

2.206 .291

2.199 .291

2 .240 • c95

2.225 .293

2.219 .295

2.225 .295

2.231 .295

2.225 .294

2.225 .296

2.226 .293

2.222 .295

2.221 .295

2. 189 • cob

2.178 .286

2.185 .286

2.178 .290

2.177 .288

2.177 .290

2.183 .287

2.173 .291

2.190 .287

2.180 .289

%

nC

4

H lniC

5 H 1?

.283 .010

.284 .010

.282 .010

.283 .011

.284 .010

.284 .009

.284 .011

.283 • 00H

.285 .010

.286 .009

.283 .010

.285 .008

.287 .010

.287 .009

.287 .010

.290 .009

.288 .010

.288 .009

.288 .010

.289 .010

.288 .010

.290 .010

.279 .010

.284 .011

.279 .011

.280 .011

.280 .009

.279 .009

.282 .009

.284 .007

.279 .010

.281 .009

Heati ng Value

J 5 H

1 9 MJ/m 3

.011 41 .076

.011 41 .078

.011 41 .078

.010 41.069

.011 41 .074

• 0 1 J 41. 0 79

All • Oil 4 1 . 0 77 .013 41.069

.012 41.079

.011 41.078

41.081

.013 41 .081

.011 41.124

.010 41.113

.011 41.112

.011 41*114

.011 41.118

.012 41.119

.012 41.115

.013 41.118

.011 41.115

.013 41.119

.011 41 .046

.013 41.039

.010 41 .041

.011 41.039

.012 41.039

.010 41.034

.011 41.040

.014 41 .046

.011 41 .040

.011 41.033
Table 7.1.9. Data for determining the effect of carrier gas flow rate on gas chromatograph analysis accuracy and precision.

Flow Rate scm^/min

Integrator N

2 CH

4

C

2 H

6 26.5 A .599 90.068 6.533

26.5 B .603 90.065 6.539

26.5 A .597 90.071 6.537

26.5 B .594 90.073 6.532

26.5 A .599 90.068 6.537

26.5 8 • 599 90.057 6.544

26.5 A .598 90.056 6.539

26.5 B .599 90.065 6.539

26.5 A .600 90.072 6.540

26.5 B .595 90.071 6.541

24.2 A • 606 90.040 6.531

24.2 B .525 90. 1 14 6.547

24.2 A • 607 90.065 6.517

24.2 B • 522 90.153 6.533

24.2 A • 610 90.045 6.528

24.2 B • 518 90. 127 6.552

24.2 A .610 90.043 6.535

24.2 B • 514 90.138 6.551

24.2 A .609 90.049 6.534

24.2 B .511 90.141 6.551

27.6 A • 607 90.062 6.537

27.6 B .614 89.921 6.630

27.6 A • 608 90.053 6.537

27.6 R • 612 89.924 6.632

27.6 A .604 90.109 6.523

27.6 B .617 89,920 6.630

27.6 A .608 90.093 6.544

27.6 B .616 89.875 6.662

27.6 A .607 90.046 6.545

27.6 B .615 89.883 6.655

Composition, nol % Heating

Value

C

3 H 8

4 10

nC .H,

„

4 10

iC c H, 0

5 12 nC-H, „

5 12

3 MJ/m

2.202 .292 .283 .010 .012 41.075

2.200 .290 .283 .009 .010 41.069

2.198 .291 .283 .010 .012 41.074

C o C- u -* ?«5 • nU lt ?c 2.200 .291 .284 .010 .011 41.074

2.201 .292 .283 .011 .012 41 .078

2.209 .292 .284 .010 .011 41.081

2.201 .291 .284 .009 .012 41.074

> 1 O 1 2. 1 V

. C*» J • CO J A 1 A .010 • U 1 c A 1 ATA 41 . |J 1 U 2.198 .291 .284 .009 .011 41.074

2.227 .293 .284 .010 .008 41.083

2.214 .294 .287 .010 .009 41.115

2.218 .292 .283 .010 .008 41.072

~y 1 Oft

. 2^1 . CO' .010 A ft Q 41. i)f 1 2.224 .293 .283 .010 .008 41.077

2.206 .293 .286 .009 .008 41.111

2.221 .292 .283 .010 .007 41.076

2.205 .291 .285 .009 .007 41.108

2. c 1° . 29c • CO J • 010 Aft?. 0 0 f

/. 1 A "T "l 41 .0 7

J

2.205 .291 .284 .010 .037 41.109

2.201 .292 .279 .010 .012 41.069

2.230 .297 .289 .009 .011 41.119

2.204 .293 .284 .010 .011 41.074

2.229 .296 .289 .009 .009 41.118

2.168 .291 .283 .010 .011 41.049

2.224 .297 .288 .010 .012 41.117

2.157 .293 .284 .011 .011 41.050

2.240 .298 .288 .009 .011 41.134

2.203 .292 .285 .010 .011 41.077

2.234 .297 .292 .011 .012 41.134
APPENDIX 7.2. RECOMMENDED CRITERIA FOR SELECTING A GAS CHROMATOGRAPH

FOR USE IN ANALYZING VAPORIZED LNG SAMPLES

Based on our experiences during this project, we recommend the following features be incorporated into any gas chromatographs used for analyzing

vaporized LNG samples:

a) automatic valve switching,

b) hot-wire filament detector with a thermal protect device to minimize

the risk of oxidizing the filaments; the detector cavity should

have minimal gas volume,

c) a separate electrical input line for the detector power supply,

d) carrier gas flow control by pressure instead of mass flow, and

e) valve and column ovens which are accesible for leak checking all

fittings

As a precaution, we recommend that the thermal conductivity detector

power input be connected to a constant voltage transformer.

For the digital integrator we recommend that the "memory protect"

feature be used; also, it is recommended that a constant voltage transformer

be used with the digital integrator.

149
APPENDIX 7.3. METHOD FOR COMPUTING THE UNCERTAINTY OF A GAS ANALYSIS

AND A METHOD FOR REJECTING A GIVEN ANALYSIS

This appendix suggests useful statistical techniques for computing the

uncertainty in composition measurement; also, it describes a simple procedure for rejecting a given analysis from a set of replicate analyses of

the same sample. Examples are given for both methods.

7.3.1. Computing the composition uncertainty of a given sample.

As mentioned in section 2.2., a logical way to estimate the error in a measurement process is to treat the error as composed of two parts — accuracy

and precision. By following the recommendations of section 4.6.1, the only

source of bias in a gas chromatograph analysis is the error in the calibration gas composition. The total uncertainty ( + D) (and how they estimated

it) of each component's composition should be given by the supplier of the

calibration gas. If possible, the composition should be verified by another

gas analysis facility.

The size of the random error (i.e., standard deviation) will be unique

to each gas chromatograph-integrator system; however, comparable systems

should have comparable standard deviations. Test results showed that the

standard deviation for calibration and analyses can be assumed equal. If we

make N^ calibration runs before analyzing a gas sample N^ times, the value

and total uncertainty of a given component (or derived property such as heating value) will be

x + (D + s«t y 1/N + 1/N

C

) (7.3.1)

where x is the average value (i.e., x = E x.),sisan estimate, based on

i=l 1 replicate measurements, of the standard deviation and t the Student's t

statistic for the desired confidence interval (e.g., 99 percent). There are

two choices for the value of s — one is to compute s from measurements on

the given sample, i.e.

V

NA

E (X. - x

i

) 2 /(NA

-l) . (7.3.2)

i=l

The second, and preferred, choice is to use the composite standard

deviation, s , which is based on all previous sets of analyses. Since s^ is

p

c

P

computed from many analyses it more closely represents the true standard

deviation of the measurement process. The composite, or pooled, standard

deviation is given by

VM( E j=l

M

s^ =V< £ (Nzn- 1 ) s *)/ 1 (N, • - 1 ) (7.3.3) AJ J j = l

AJ

150
where NA

_. is the number of replicate analyses taken on the jth sample, s. is

the estimated standard deviation for that set (computed using 7.3.2) and M

is the total number of samples analyzed.

The Student's t statistic used will depend upon the chosen confidence

interval and the chosen standard deviation (s or s )

P

This approach could be applied to the sampling system if several samples could be taken during a period when the LNG composition is constant.

The results of four replicate analyses of a sample give the following

methane contents: 90.080, 90.032, 90.080 and 90.070 mol percent. Prior to

these analyses, there were three calibration runs in which the response

factors for each component were averaged. The stated uncertainty in the

methane content of the calibration gas is + 0.003 mol percent.

The average methane value is 90.066 mol percent and the estimated

standard deviation, s, is 0.023. Using these values, the Student's t statistic for three degrees of freedom (i.e., - 1) and a 99 percent confidence

interval from table 7.3.1 of 5.841, we obtain the total uncertainty in the

methane content:

However, prior to this analysis, a sufficient number of analyses were

made so that I (N . - 1) =52 (which is the number of degrees of freedom),

and the composite standard deviation, s^, is 0.020. Based on 52 degrees of

freedom, t is approximately 2.68 and the total uncertainty becomes

This value is 60 percent smaller than the other; also, it is more representative of the expected uncertainty.

The size of the confidence level depends upon the number of analyses;

however, the width decreases as the square root of 1/NA

- This makes it

unattractive to make more than three or four analyses. If there had been

ten analyses instead of four in the above example the confidence interval

would be + 0.038; this is only 13 percent smaller than when using four

analyses

The value of s^ can be updated using the above data and equation 7.3.3,

i.e. ,

Example 1

+ 0.106 mol %.

Aj

+ (0.003 + 0.020*2.68 / 1/4 + 1/3) = + 0.044 mol % m

P

* which is a negligible change in this case.

s 0.0202

151
Table 7.3.1. Values of the Student's t distribution used to calculate

confidence intervals for the mean [5]

Degrees of

Freedom

Student's t Distribution

Confidence Interval

95% 99%

1 12.706 63.657

2 4. 303 9.925

3 3.182 5.841

4 2.776 4.604

5 2.571 4.032

6 2.447 3.707

7 2.365 3.499

8 2.306 3.355

9 2.262 3.250

10 2.228 3.169

11 2.201 3.106

12 2.179 3.055

13 2.160 3.012

14 2.145 2.977

15 2.131 2.947

16 2.120 2.921

17 2.110 2.898

18 2.101 2.878

19 2.093 2.861

20 2. 086 2.845

21 2. 080 2.831

22 2.074 2. 819

23 2.069 2.807

24 2. 064 2.797

25 2.060 2.787

26 2. 056 2.779

27 2.052 2.771

28 2.048 2.763

29 2.045 2.756

30 2. 042 2.750

40 2.021 2.704

60 2. 000 2.660

120 1.980 2.617

OO 1. 960 2 . 576

7.3.2. Methods of rejecting an analysis.

To reject a given analysis we need to run two or more analyses and

compute the difference, R, between the maximum and minimum measured values.

One of these two points can be rejected if

R = max

- x > A* s min p

(7.3.4)

where A is a function of the number of analyses, N (ref . [5] , p. 17-3)

Table 7.3.2 lists the values of A. Using this criterion, only one out of one hundred rejected analyses will be rejected when it should not have been.

152
Table 7.3.2. Values of A as a function of N,

.

A

NA

A7V

2 3. 64

3 4.12

4 4.40

5

6 4.76

7 4.88

8 4.99

9 5.08

10 5.16

Example 2 , Three replicate analyses are run and the measured methane contents are

90.132, 90.021 and 90.032 mol percent. From previous analyses we know that

s is 0.020. Can the first value be rejected?

P

Using equation 7.3.4,

p R = 90.132 - 90.021 > 4.12-0.020

0.111 > 0.082.

Therefore, the first point should be rejected. However, if the first

value had been 90.103 mol percent, it would not be rejected using this procedure.

153
APPENDIX 7.4 SAMPLING DATA

This appendix lists all of the measured operating variables in the

sampling tests according to run number. The sample analysis along with the

computed liquid density are listed after operating variables for each test.

All compositions were measured using integrator A unless stated otherwise.

7.4.1. Laboratory Test Data

In table 7.4.1 "Mix" refers to samples of the mixture present in the

apparatus during the given test, e.g., 1; analyses of the corresponding gas

cylinder will have a Mix number greater than 100, e.g., 101. Mix 100 represents analyses of the calibration gas (see table 4.2, mixture E) . The

listed heating values are ideal gas values computed using the values given

3 in table 2.2; to convert from MJ/m to Btu/scf multiply by 2 6.845.

154
Table 7.4.1. Laboratory Test Data Probe Test 1 (runs 20 through 32 were not used in any statistical evaluation).

RUN 0 ATE TEMPERATURE PRESSURE LNG FLOW RATE SAMPLING OELTA P PROBE VAPORIZER

NUMBER K MP A LPM RATEt SLPM KF A POWER, WATTS

1 12/22 113.0 .C99 3.41 2.0 25. S 7.6

2 12/22 113.0 .C99 3.41 2.0 25. R 7.0

3 12/22 113.0 .099 3.44 2.0 25. P 7.0

4 12/22 113.0 .100 3.48 6.0 25. P 64.0

5 12/23 113.0 .10 0 3.44 6. 0 25

S 70.1

6 12/23 113.0 .101 3.41 6. 0 26. R 70.6

7 12/23 113. 0 .100 3.44 2.0 27. P 6.8

8 12/23 113.0 .10 0 3.48 2.0 19. P 12.6

9 12/23 113.0 .101 3.44 2.0 12. P 2.5

10 12/2 3 113 .0 .10 3 5.79 2.0 12 • p 4.0

11 12/23 113.0 .102 5.90 2.0 13. R 4.0

12 12/27 113.0 .102 1.93 2. 0 25. R 8.9

13 12/27 113.0 .102 1.89 2.0 25. S 8.9

14 12/27 113.0 .10 2 1.89 2.0 25. P 8.9

15 12/27 113.0 .102 1.89 6.0 25. P 67.7

16 12/27 113.0 .102 1.85 6. 0 25. S 64.4

17 12/27 113.0 .10 3 1.89 6.0 25. R 67.7

18 12/28 120.0 .173 3.67 4.6 25. R 44.6

19 12/28 120. 0 .173 3.79 4.6 25. P 45 . 9 20 12/23 120.0 .173 3.79 4.6 25

S 47. 3

21 12/28 113.0 . 124 3.71 2.2 25. S 10 .1 22 12/28 113.0 .125 3. 75 2.2 25. R 11.6

23 12/28 113.0 .125 3.75 2.2 25. P 11.4

24 12/29 113.0 . 126 3.75 2.2 25. S 10.8

25 12/29 113.0 .126 3.79 2.2 25 . R 13.8

26 12/29 113, 0 .126 3.79 2.2 25. P 13.1

27 12/29 113.0 .12 6 3.75 6.7 24. P 68.5

28 12/29 113.1 . 128 3.79 6. 7 26. R 69.7

29 12/29 113.

.127 3.79 6.7 25. S 69.7

30 1/03 113. u .251 3.79 3. 1 25. S 31.4

31 1/03 113.0 .252 3.82 3.2 25. P 33.4

32 1/C3 113.0 .253 3.79 3.2 25. R 33.1
Table 7.4.1. Probe Test 1 (continued)

Run

lumber Time Mix CH4

C

2 H6

1 1307 0.033 85. 6*6 11.68 0 2 13*6 0.003 35.667 11.6*0

2 1*0* 0.300 85.692 11.620

2 1*26 101 0.000 85.619 11.720

3 1*51 0.0 jQ 85.557 11.760

3 1507 C.30Q 85.533 11.760

3 152* ! 0.000 85.5*o 11.759

<* 151*7 0.003 85.639 11.660

1+ 1602 0.003 85.691 11.653

5 1012 1 0.000 85.611 11.699

5 1031 101 0.000 85.610 11.710

6 1059 O.COO 85.675 11.6*9

6 1115 0 . C 0 0 85 . 6*9 11.660

7 1251 0.000 85.723 11.619

7 1308 1 0.003 85.j7 11 .6*0

8 13*7 1 0.000 85.663 11.650

8 1*0* O.COO 85.693 11.633

8 1*22 101 C.0Q3 85.608 11 . 7 20

9 1**7 O.COO 85.723 11.610

9 150* 1 0.003 85.73* 11.609

10 1531 1 0.003 85.533 11.730

10 15*9 ! 0.000 85.517 11.730

11 1607 ! 0.003 85.679 11.6*0

11 1623 0.003 35. 695 11.6*1

11 16*1 101 0 . U 0 J 85.555 11.7*1

12 1019 0.000 85.672 11.675

12 1038 0.003 85.691 11.637

12 1057 0 . 0 u 0 35.67* 11 .66*

12 956 101 0.000 85.591 11.739

13 11** 0.003 85.683 11.6*9

13 1203 0.000 85.728 11.6 30 1* 1235 0.003 85.66* 11.621

1* 1252 0.003 85.666 11.621

15 1336 0.003 85.6*8 11.689

15 135* 1 0.003 85.6*9 11.685

15 1*10 0.003 85.6*3 11 .67*

16 1605 0.003 85.76* 11.611

16 1621 0.000 85. 703 11.659

16 15*6 101 0.000 85.672 11 .699

17 16*2 0.000 85.637 11.673

17 1658 1 0.000 85 .696 11 .669

18 1002 0.000 85.713 11.660

18 1018 ! 0.000 85.707 11.667

18 103* 0.000 85.723 11.673

19 1112 0.003 85.565 11.719

19 1130 0.000 85.511 11.759

19 11*7 0.000 85.*87 11.785

19 1203 0.033 85.503 11.771

20 1251 O.uOO 85. 713 11.660

20 1308 0.000 85.727 11.651

Hedti ng

Val ue none i t v C

3 H 8

iC

4

H 10nC

4

H 1Q 3 3 MJ/nT gm/cm

l.*01 .5*1 .730 *2 . 982 .*691

1.399 .55* .7*0 *2. 989 . *6 91 1.391 .553 .7h* *2. 981 .*690

1.386 .539 .736 *2 . 988 . *691

1 . 399 .5** .7*0 *3. 015 . *69*

1 .*0 3 .552 .751 *3. 033 . *695

l.*0* .5*8 . 7*3 *3. 023 . *69*

1.381 .5** .726 *2 . 96* . *689

1.382 . 5*3 .73* *2 . 966 . *689

1 .*01 .5*7 .7*2 *3. 003 . *692

1.391 .555 .73* *3. 000 . *692

1.390 .55C .736 *2 . 960 . *690

1.38* .5*8 .739 *2 . 986 . -+691 1.378 .5*7 .733 *2.959 • *689

1.375 .5*6 .730 *2. 962 . *689

1.39* .551 .7*1 *2 . 986 .*691

1.395 .5*9 .733 *2. 97* • *690

1 . 39* .5*7 .731 *2.995 .*692

1.380 .5*8 .739 *2 . 96* . *689

1.371 .5*9 .737 *2, 957 . *688

1 .*17 .57* .7 75 j^»<Q71 .*698

l.*15 .571 .768 *3. 061 ,*697

1.383 .5*8 .7*5 *2.982 ,*691

1.380 .5*7 .737 *2. 970 .*690

l.*05 .55* .7*5 *3. 025 . *69*

1.377 .5*0 . 7 36 *2.971 .*690

1.38* .5*6 .7*2 *2 . 97* .*690

1.379 . 5** .739 *2 . 975 . *690

1.39* .5*3 .73* *3. 000 .*692

1.386 . 5** .738 *2. 97* . *690

1.380 .537 .725 *2. 9*8 . *68 8 l.*09 .557 .7*9 *2. 999 .*692

1 .*07 .553 . 753 *2 . 998 .*692

1.393 .5*C .730 *2.979 .*691

1 .397 .539 .730 *2 . 980 . *691

1 .*0 0 .5*3 .7*0 *2. 990 . *691

1.371 .53* .720 *2. 931 ,*686

1.378 .537 .723 *2. 95* .h688

1 . 375 .536 .718 *2. 958 .*689

1.381 .536 . 726 *2 . 960 .*669

1.378 .53* .723 *2. 95* . *688

1.377 .529 .720 *2 . 9*5 . *589

1.38* .527 .715 *2. 9** . *589

1.373 . 525 .739 *2.932 .*588

l.*20 .5*8 .7*8 *3. 025 .*596

l.*20 .553 .758 *3. 0*3 .*598

l.*19 .550 .759 *3. 05* .*598

l.*25 .550 .751 *3. 0*7 .*598

1.380 .53* .712 *2.9** .*589

1.382 .52* .716 *2.937 .*588
Table 7.4.1. Probe Test 1 (continued)

Run

um bet* Time Mix N

2 CH

4

C

2 H6

5 n 1 £ c * lux n nn i u • u U J 0 5 • D o 5 11 7 51 1 1 . I C 1 21 1 5 c 1 C • 5 H o 8 5. 181 11.619

"> 1 c 1

1 ccc cc; z. 5

• 5 H c O 5 . c U U 11.610

5 5 lO 1 J c

c ^ a

« 5 5 0 OH. Qj. Q i. 7

11 7C 1 11. O J 22 16h5 2 .5V2 8^.952 11.749

5c o7 17 0 8 2 » 5 4 H 5 5 • 1 6 2 lit'- **7 2 3 1 7 2h 2 # 5 ^ i+ 85 . 1 h 7 11.660

2** 10 i+3 • 546 8 5.231

24 10 59 2 • 546 85.223 11.590

25 1136 2 • 547 85.289 11.520

5 5 115c • 54 8 85.279 1X 1X

-. 7 7o Ao

5 c; c 5 115c 117O 1UC 10 5 • u c o

a 7

111 t;i (1 1 . 5 1 U c 0 lc JO c • CU5 * A0

at; n qc 1111 * P.7Q O O 7 C D 1 5 c; 1 1 c 5 1 c • 54 8

AC; O .? • nU H q2 1 1 A/aQ 26 1309 2 .546 85.063 11.639

c / 1 0 *+• 5 4 d 0 5. c c 5 11 c;7Q 1 1 • 5 f 5

c\5 7f X O 5 « c. X X . 5 l 5 57C (

1 i. 5 n 1 H c u 1 u U1 7 A QC A A 7 0 • 5 U 5

5 ft C 0 1HHD 5 O 5 . too 1111 .50? C, c, q 28 1503 2 .5<*9 35.269 11.560

5 Q i c j. ? c • 5*+ o 0 5 • tHU 1111 ^ a n • 5 0 U

1 c;7 15?r c •

c;5 4 7f a c 5 t c

0 5. c C 5 1111 Q i 5u7

5 Q 1 ^ 5 c: 1 5 c 5 11 (11 Ul u*uuu Ac; O 5 7 7 1 . i OX 11 k ^ n 1 1 • D D U o u

1 n n n i u u u o HU • 7O 07 Q5 AOX.1 Qf70c? 1111 «1lOUAn

7o nu 1 fi 5 A 3 4 • 3 3 9 81.968 11.140

31 1113 3 4.330 81.891 11.200

31 1131 3 4.335 81.908 11*180

31 1159 101 0.000 85.615 11.719

32 1225 3 4.333 82.007 11.130

32 12*2 3 4. 340 81.993 11.139

C

3 H 8

iC

4

H 10nC

4

H 1Q

Heating

Value

MJ/m 3 Density

gm/cm 3

1.390

1.385

1.383

1.1,26

1.1+36

• 5 27 ,5h0

.535

.557

.557

• 727 .733

.730

.762

.761.

kZ . 97 3 "2.752

kZ. 7kZ

kZ . 8^5

kZ. 858

• h591

.1+703 .1+703

.1+712

.1+712

1 to n

x . o o U 1.387

1.381+ 1.378

1.381

. 5 o 1 .535

.535

.532

.537

7 "7 t. . / 0 H .728

.72^

.730 .726

Hi. I

U 1*2. 756

h2. 728

h2.73C

h2.712

. * f U o

.1+701* .1+702

.1+7C2

.i+700

1.370

1.31*6

1.1+15 1.hh2

1.h31*

.536

.536

.555 .563

.55h

• 7 2 7 .70**

.71.8 .753

hZ .712

kZ . 866

i*2. 798

i+2. 827

h2.822

/ 7 rt n

. H f U U .^683

.1+707 .<+710 .i*709

1.380

1.376

2.989

1.372

1.377

.536

.537

.523

.527

.532

• f 30 .727

.712

.720

.713

h 2 . 73 2 i*2.727

42. i*23 1+2.706 42.705

, 7(1 7

• +701

.1+717 .1+699

.i+698

1.379

1.369

1.371

1.32<*

1.331*

• 533

.529

.535

.520

.519

• 720

.721

.703

.695

.701

i*2 • 719

1+2.706

i*2.932

hI.IOh

hI.107

i. 7 n + .1+700 .1+687

.1*789

.1*789

1.353

1.350

1.396

1.32h

1.321*

.523

.525

.51*6 .513

.515

.703

.702

.72i»

.69<» .690

i*l. li*i* i*l. 135

1*2.989

1*1.090

1*1. 089

.1*792 .h791

.1*693 .1+788

.1*788
Table 7.4.1 . Probe Test 2

RUN DATE TEMPERATURE PRESSURE LNG FLOW RATE SAMPLING DELTA P PROBE VAPORIZER

1BER K MP A L P M RATE • SLPM KP A POWER. W/

33 1/03 113.0 .147 3. 75 2.4 26. R 16.2

3<f 1/03 113.0 .148 3.71 2.4 25. P 17.4

35 1/03 113.0 .148 3.79 2.4 26. S 18.9

36 1/03 113.0 . 148 3. 79 2.4 25. R 16.0

37 1/03 113.0 • 148 3.79 2.4 25. S 16.0

38 1/03 113.0 .148 3.79 2.4 25. P 16.0

39 1/04 113. 0 .142 3.82 7.1 25. s 94.1

40 1/04 113.0 .149 3.79 7.3 25. R 78.3

41 1/04 113.0 .147 3.79 2.4 25. P 73.5

42 1/0 4 113.0 7 O I . C CP. K lit 1*

43 1/04 113.0 .147 3.75 7.2 25. s 77. 9 44 1/04 113.0 .147 3.79 7.2 25. P 77.9

45 1/04 113.0 .150 3.75 2.4 25. P 18.9

46 1/04 113.0 .150 3.79 2.4 25. s 36.5

47 1/04 113.0 . 149 3.75 2.4 25 • R 13.7

49 1/04 113.0 .150 3.75 2.4 25. R 18.7

49 1/05 113.0 .148 3.75 2.4 25. R 19.1

50 1/05 113.0 .148 3.79 2.4 25. s 19.4

51 1/05 113.0 .149 3.75 2.4 25. P 19.4

52 1/05 113.0 .149 3.82 7.2 25. S 71.4

53 1/05 113.0 .150 3.79 7.1 26. P 66.0

54 1/05 113.0 .150 3.79 7.0 25. R 74.8

55 1/05 113.0 .152 3.79 5.8 26. S 58.5

56 1/05 113.0 .150 3.79 5.5 26. P 54.6

57 1/05 113.0 .155 3.63 5.6 24. R 52.2
Table 7.4.1. Probe Test 2 (conti

NuSber Time Mix N

2 33 1323 4 1.340

33 1340 4 1. 341

34 1426 It 1.342

35 1448 4 1.339

35 1505 4 1.338

36 1548 4 1.341

36 1603 4 1.335

36 1620 101 0,003

37 1639 4 1.338

37 1655 4 1.336

38 1727 4 1.338

38 826 4 1.336

39 1006 u 1.341

39 1022 4 1.340

39 856 101 0.000

40 1039 4 1. 341

<*0 1055 4 1.350

40 1111 It 1.338

41 1201 4 1.339

41 1217 4 1.338

42 1250 4 1.340

43 1319 4 1.354

43 13 36 (. 1.343

44 1424 4 1.340

44 1440 4 1.340

45 1459 4 1.338

45 1515 4 1.351

46 1533 L, 1.336

46 1550 4 1.337

47 1609 4 1.338

47 1625 4 1.340

48 1644 4 1. 338

48 1700 k 1.341

48 1716 101 0 .GOO 49 911 4 1.340

49 944 4 1.331

50 1008 4 1.337

50 10 24 4 1 .340

51 1044 4 1. 339

51 1059 4 1.352

51 1120 101 0.000

52 1143 4 1.335

52 1159 4 1.332

53 1221 4 1.337

53 1255 4 1.334

54 1321 4 1.340

54 1337 4 1.340

54 1350 101 0.000

55 1459 4 1.337

55 1517 4 1.339

nued)

CH

4

C

2

H

6 C3

H 8 iC

4

H 10 83.913

83.927

83.907

83.960

83. 985

11.970

11.960

11.970

11.950

11.939

1.450

1.450

1.445

1.419

1.429

.569

.566

.570

.570

.552

83.885

83.919

85.713

83.777

83.779

11.959

11.940

11.674

12 .040

12.030

1.458

1.449

1.379

1.480

1.490

.577

.581

.534

.581

.587

83.798

83.753

83.946

83.946

85.605

12.000

12.020

11.979

11.979

11.729

1.491

1.493

1.425

1.426

1.392

.589

.589

.555

.555

.536

83.961

83.934

83.952

84. 090

84. 084

11 .970

11.969

11.979

11. 870

11.879

1.425

1.430

1.417

1.403

1.406

.551

.559

.555

.548

.546

83.952

83.798

83.964

83.947

83.956

11.969

12.080

11.959

11.980

11.969

1.438

1.437

1.424

1.425

1.429

.549

.560

.553

.555

.552

83. 898

83. 887

83.984

83.962

83.942

11.990

11.990

11.961

11.980

11.980

1.440

1.450

1.425

1.423

1.424

.563

.561

.547

.553

.557

83.905

83.953

83.939

85.649

83.965

11.989

11.950

11.968

11.702

11.961

1.440

1.424

1.429

1.377

1 .423

.560

.561

.557

.543

.563

83.965

83.997

83.993

83. 862

83.853

11.969

11.940

11.930

11.999

11.999

1 .419

1.421

1.431

1 .456

1.459

.558

.555

.555

.570

.571

85.617

83.967

83.969

83. 974

83.984

11.730

11.970

11.980

11.971

11 .961

1.389

1.424

1.418

1.429

1.429

.538

.557

.559

.552

.549

83.954

83.954

85.634

83.994

83.957

11.969

11.969

11.709

11.951

11.970

1.427

1.432

1.400

1.428

1.437

.555

.555

.537

.550

.554

Heating

iCH-, „ Value Densi ty

4 10 3 MJ/m

. 757 42.632 • 4741

.756 42.625 .4740

. 766 42.637 .4741

.762 42.614 .4739

.757 42.598 .4738

.780 42.659 . 4743

.776 42.651 .4742

.700 42.937 .4688

.785 42.703 .4746

.778 42.706 .4746

.784 42.7 04 • 4746

.809 42.733 .4748

.754 42.606 .4739

.754 42.607 .4739

.738 42.994 .4692

. 752 42 .598 .4738

.758 42.609 .4739

.759 42.606 .4739

.750 42. 554 .4734

.745 42.554 .4734

.752 42.604 .4738

.771 42.655 . 4744

.757 42.600 .4738

.754 42.606 .4739

.754 42.603 .4738

.771 42 . 640 .4741

.762 42.631 .4741

.747 42. 590 .-+737 .745 42.597 .4738

.759 42.613 . 4739

766 42.632 • 4741

.774 42.620 .4740

.766 42.616 ,<+739

.729 42.976 .4691

.748 42.601 .4738

.758 42.609 .4738

.751 42.591 .4737

.751 42.593 .4737

.775 42.660 .4743

.766 42.650 .4743

.726 42.984 .4691

.748 42. 601 .4738

.742 42.596 .4738

.737 42.590 .4737

.743 42.591 .4737

.755 42.605 .4739

.750 42.604 .4738

.720 42.978 .4691

.740 42.585 .4737

.743 42.600 .4738
Table 7.4.1 Run Number

Probe Test 2 (continued)

Time Mix N, CH,

C 2 H 6 C 3 H 8iC 4 H 10nC 4H 10

Heating

Value MJ/m 3 Densi ty gm/cm

56 1538 4 1. 341 83. 969 11.970 1.420 .552 . 748 42.593 .4738

56 1554 4 1.334 83.967 11.970 1.439 .551 .740 42. 598 .4738

57 1611 J* 1.343 83. 963 11.950 1.432 .559 .753 42.603 .4739

57 1628 4 1.336 83. 967 11.950 1.435 .561 .751 42. 607 .4738

57 1640 101 0.000 85.607 11.720 1.404 .539 .730 42.993 .4692
Table 7.4.1 . Probe Test 3 RUN DATE TEMPERATURE PRESSURE LNG FLOW RATE SAMPLING DELTA P PROBE VAPORIZER

NUMBER K MP A LPM RATEf SLPM KPA POWER, WATTS

58 1/31 111.0 . 127 7.19 5.6 25. S 57.0

59 1/31 111.0 .127 7.19 5.6 25. R 57.0

60 1/31 111.0 .126 7.19 5.6 24. P 60 . 8 61 1/31 111.0 .128 1.89 5.6 71 . R 58.9

62 1/31 111.0 . 128 1.89 5.6 69. S 64.0

63 1/31 111.0 .127 1.89 5.6 7:. P 69.3

6<* 1/31 111.1 .128 1.89 5.6 25. P 64.0

65 1/31 111.0 .126 1.89 5.6 25. S 6h. 0 66 1/31 111.0 .126 1.89 5.6 25. R 64.4

67 1/31 120.0 .226 1.89 4.2 26. R 46.2

68 1/31 120.0 .227 1.89 4.2 25. P 45.6

69 1/31 120.0 .227 1.89 4.2 25. S 4*5.6 70 2/01 120. 0 .226 7.19 4.2 25. S 53.7

71 2/01 120 . Q .226 7.19 4.2 25. R 49.7

72 2/01 120 .0 .227 7.19 4.2 25. P »*7 .6

73 2/01 120 .0 .227 1.89 4.2 25. R 50. 4 74 2/01 120. 0 .227 1.89 4. 2 25. S 50.4

75 2/01 120 . 0 .227 1.89 4.2 25. P 48.3

76 2/01 120 .0 .231 1.89 4.2 69. R 40.6

77 2/01 120.0 .231 1.89 4. 2 69. S 43.6

78 2/01 120.0 .230 1.89 if.70. P 41.6

79 2/02 111. 0 .127 1.89 5.6 25. s 63.6

eo 2/02 111.0 .127 1.89 5.6 25. p <47.6 81 2/02 111.0 .127 1.89 5.6 25. R 60.5

82 2/02 111.0 .126 7.19 5.6 25. P 62.8

63 2/02 111 . 0 .126 7.19 5.6 25. S 66. 4 84 2/02 111.0 .127 7.19 5.6 25. R b7.Z

85 2/02 111.0 .127 1.89 5.6 70. P 66,4

86 2/02 120.0 .226 1.89 4.2 69. S 51.5

87 2/02 120.0 .229 1.89 4.2 70. R 1*9.3

88 2/03 120.0 .229 1.89 4.2 70. S 38. 4 89 2/03 120.0 .229 1.89 4.2 69. R 1*1.6 90 2/03 120.0 .229 1.89 4.2 70. P 4+1.6 91 2/03 120.0 .228 7.19 4.2 25. S 1*1.

92 2/03 120.0 .227 7.19 4.2 25. P i*1.0

93 2/03 120 . 0 . 229 7.19 i*.2 Zk. R i*1.0

9i* 2/03 111. 0 . 127 1. 89 5.6 69. R 63.2

95 2/03 111.0 .127 1.89 5.6 70. S 52.2

96 2/03 111.0 .127 1.89 5.6 70. P 63.2
Table 7.4.1. Probe Test 3 (continued)

Ru n dumber Time Mix N

2 CH

4

C

2 H

6

58 10 58 5 1.219 84 • 565 9.510

sJ ao 10 35 X U 7 1.256 ru . f, n h Q . (i 7f> •iQ j j 11 11 ?uL t 5 1.220 84 .546 9.535

fed 1 1 4 8 5 1.223 84 .430 9 • 5 74 60 1205 5 1.222 84.447 9.552

61 1222 5 1.218 84.609

Pi 7 1 7ll7 B 1 7 1 Q OH. RU Cih7 3 O O Q . 5 77

Pi7 1 O l. H 1 pi* n 1 • C H J

ftii O H • 5 7f AO 62 1311 105 1 • 237 84.565 9. . 5 7P, 63 1354 5 1.214 84.515 9.561

64 H19 5 1.218 84.5 85 9*519

65 1441 5 1.213 84.5 88 9*519

66 1504 5 1.215 84.5 47 9. 525

67 15 33 5 1.215 84.5 51 9.535

68 1557 5 1.221 84.532 9.546

69 1622 5 1.217 84 • 5 6 0 9.529

69 1641 10 5 1. 242 84. 547 9* 524

70 1019 5 1.223 84.5 77 9.504

7 0 10 37 105 it 241 84.5 87 9.499

71 1118 5 1.223 84. 528 9.518

72 1144 5 1. 223 84 . 612 9*509

73 1214 5 1.218 84 • 5 85 9*512

74 1238 5 1 . 77 n 84 . 5 27 1255 1.219 84.5 74 9*517

75 1314 5 1.217 84.588 9.526

76 1512 5 1*219 84. 5 82 9*515

77 15 34 c

9 1 . 7 1 f> RUOH . 5i> 7c 7C q s s n 7f oA CJ 1.771 OHAll 5VOO7 A o, 5 7 7

7 8 1621 105 1. 252 oh. ?yu

79 1038 5 1.218 84.455 9.615

79 1058 5 1. 204 84. 561 9*529

79 1137 5 1*219 84.5 20 9*551

79 1155 105 1.237 84.4 85 9*595

80 1217 5 1.214 84.5 0 6 9*540

80 1238 105 1.235 84.523 9.557

81 13 01 1*216 84.5 35 9 . 556

82 1325 5 1.219 64.588 j % j & j 83 1351 C X . C X 7 All OH .»?HU ^ i* n Q • 5 77

84 1413 1 . 77S 84 • 3 55 9*636

Qi, 1 4 59 5 1.214 84.512 9* 537

85 1516 5 1.217 84.507 9.572

86 1539 5 1.213 84.530 9.564

87 1626 5 1.215 84.509 9.559

88 959 5 1.216 84.549 9.548

98 941 105 1.238 84.543 9.537

C

3

H 8iC

4

H 10nC

4

H 1Q

Heating

Value

MJ/m 3 Densitygm/cm 3

3.524

3.493

3.514

3.554

3.558

.481

.479

.482

.494

.494

.701

.690

.704

.725

.728

43.028

42. 976

43. 032

43.093

43.091

.4788

.4786

.4789

.4794

.4793

3.495

3.505

3.503

3.500

3.521

.481

.481

.479

.480

.484

.697

.705

.689

.692

.705

43.006

43.026

42.997

43.004

43.048

.4786

,h788

.4787

.4787

.4790

3.505

3.505

3.523

3.514

3.513

.479

.4 79 .483

.483

.483

.694

.696

.707

.702

.705

43.013

43. 016

43. 040

43. 034

43. 036

.4785

.4787

.4789

.4662

.4663

3.506

3.507

3.501

3.486

3.523

.4 79 .482

.488

.482

.492

.709

.698

.708

.705

.716

43. 029

43.012

43.023

42.999

43.050

.4662

.4662

.4662

.4661

.4664

3.476

3.506

3.505

3.501

3.491

.482

.481

.483

.486

.483

.698

.698

.706

.703

.695

42. 997

43.016

43.003

43.023

43.011

.4660

.4661

.4663

.4662

.4661

3.492

3.528

3.485

3.498

3.518

.484

.482

.486

.485

.483

.708

.703

.699

.697

.711

43. 020

43.045

43.025

43.017

43.065

.4661

.4663

.4662

.4663

.4791

3.520

3.525

3.501

3.526

3.502

.488

.484

.480

.491

.479

.698

.701

.702

.723

.704

43. 040

43.043

43.032

43.066

43.024

.4788

.4789

.4790

.4791

.4789

3.507

3.488

3.520

3.576

3.539

.482

.477

.464

.469

.484

.704

.693

.710

.719

.714

43. 036

43.005

43.041

43.113

43.059

.4789

.4786

.4789

.4795

.4790

3.515

3.511

3.532

3.510

3.499

.485

.480

.483

.478

.484

.704

.702

.702

.699

.699

43.047

43.038

43.050

43.028

43.015

.4790

.4663

.4664

.4662

.4662
Table 7.4.1. Probe Test 3 (continued)

Run Number Tims Mix N„

2 CH. CH,2 6

93 1257 5 1.223 84.527 9.552

93 1315 105 1.239 84.5h7 9.534

94 1333 c 1.212 84.527 9.564

94 1350 5 1.216 84.522 9.559

95 1423 5 1.217 84. 509 9.546

96 1451 5 1.224 85.100 8.931

96 1511 5 1.217 84.539 9.55k

C

3 H8 iC

4

H 10nC

4

H 10

Heating

Value HJ/m 3 Density

gm/cm 3 3.519

3.499

3.499

3.508

3.511

.479

.482

.489

.487

.493

.700

.700

.709

.708

.724

43.033

43.013

43.045

43. 045

"43. 061

.4663

.<.662 .4789

.4789

."791

3.548

3.500

.486

.482

.711

.708

42.888

43.034

.4776

.4789
Table 7.4.1 . Probe Test 4 RUN NUMBER

146

147

1<»8 149

150

151

152

153

154

155

156

157

158

159

160

161

162

163

164

165

166

167

168

169

170

171

172

173

174

175

176

177

178

179

180

OATE

2/25

2/25

2/25

2/25

2/25

2/25

2/25

2/25

2/25

2/25

2/25

2/25

2/25

2/25

2/25

2/25

2/25

2/25

2/25

2/25

2/25

2/25

2/25

2/25

2/28

2/28

2/28

2/28

2/28

2/28

2/28

2/28

2/28

2/28

2/28

TEMPERATURE

K

11.0

11.0

11.0

11.0

11.0

11.0

20.0

20.0

20 .0 20.0

20.0

20. 0 20.0

20.0

20.0

20.0

20 . 0 20.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1 . 0

PRESSURE

MP A

.127

.126

.126

.125

.127

.126

.233

.231

.231

.228

.229

.229

.231

.231

.231

.229

.230

.229

.127

.126

.126

.127

.126

.126

.126

.126

.126

.127

.127

.127

.126

.126

.126

.126

.12 6

LNG FLOW RATE SAMPLING DELTA P LPM RATE, SLPM KPA PROBE VAPORIZER

POWER, WATTS

.23

.19

.19

.30

.26

.26

.23

.26

.26

.38

.30

.30

.30 .30

.30

. 34 .34

• 3<t .30

.30

. 34 .30

.30

.30

,3<4

.34

.34

3. 79 3.75

3.79

.31.

. 34 .38

3.79

3.79

5.6

5.6

5.6

5.6

5.6

5.6

<*. 2 t*.Z 4.2

4. 2

4.2

4.2

4.2

4.2

4.2

if.

i*.

4.2

5.6

5.6

5.6

5.6

5.6

5.6

5.6

5.6

5.6

5.6

5.6

5.6

5.6

5.6

5.6

5.6

5.6

28.

28.

28.

69.

70.

69.

71.

71.

71 . 27.

27.

27. 69.

70.

70.

2e.

28.

28.

7C . 70.

69.

27. 27.

27.

29.

29.

29. 26.

28.

2d.

29.

29.

29.

28. 27.

56.2

61.2

61.2

64.4

6- . <

6<*. 8 91.2

if 1.0

41.3

45.2

45.6

45.6

46.2

42.5

46. 2 43.2

43.6

43.2

54.8

64.0

63.6

63.2

63.6

64.0

60.5

60.5

60.5

60.5

6J.5

60.5

60.5

60.5

63.2

60.8

57.8

181 2/28 111.0 127 3. 79 5.6 27. 58.5
Table 7.4.1. Probe Test 4 (continued)

NurnHer Time Mix N

2 CH

4

146 945 5 1.214 84.616 9.508

147 10C0 5 1.214 84.606 9.507

1 L A X o -J ftOHl. c; ft £,

i 5 OO 1033 5 1.212 84. 570 9.530

150 1048 5 1.213 84.637 9.492

151 1133 c 1.213 84.618 9.513

152 1134 5 1.208 84.593 9.519

1149 C

5 1 . c 1 1 04 • o U c 9.514

15«t 1209 c 1.206 64.559 9.543

154 1230 1U5 1.252 84.539 9.538

155 1250 C 1.203 84.588 9.527

156 1307 5 1.204 84.597 9.521

151 loco Ct> 1 • c 0 ^ 84 .5 72 9.531

158 1341 5 1.213 84.607 9.500

159 1356 c 1.205 84.581 9.541

160 1412 5 1.208 84.610 9.517

161 1428 e 1. 206 84.624 9.509

IOC X H H J c fl/. C. 1 U O H •Dit

163 1518 5 1.209 84.615 9.508

164 1536 5 1.213 84.637 9.504

164 1551 105 1.236 84. 536 9.533

165 1611 5 1.208 84.612 9.509

IOC 1 k ^ ? C X1 • ?ic X c? P. L. ^ 7 k Q 5 ^ 5 167 1650 5 1.211 84. 586 9.522

168 1707 5 1.210 84 .604 9.525

169 1725 5 1.209 84.477 9.525

169 2740 105 1.241 84. 565 9.513

1 0 7

1 7Ct 1 n n 1 u u li1 Jul 7, a 1 ft UQ7

170 916 5 1.214 84.631 9.487

170 855 105 1.239 84.578 9.515

171 931 5 1.212 34.530 9.540

172 952 5 1.212 84.659 9.476

1 f C

1 n i a 1 U u 3 C 1.213 0 4 • o 2 0 y • * o u 173 1025 5 1.212 84.532 9.556

174 1044 5 1.215 84.539 9.529

175 1102 5 1.214 84.685 9.458

175 1118 5 1.212 34.664 9.434

I'D Hot c 1 . w 1 J Hi. C u 7 ^ • -> 5 1 177 1154 c 1.211 84.540 9.531

177 1225 105 1.241 84.571 9.526

178 1243 5 1.213 84.596 9.538

179 1300 c 1.215 84.631 9.490

179 1316 c 1.213 84.628 9.481

180 1331 5 1.207 84. 606 9.505

181 1350 5 1.211 84.635 9.502

181 1407 105 1.240 84.587 9.505

Heati ng

r h if h nL

4

M 10 Value Density

MJ/m

3 gm/cm^

3.486 .480 .697 43.303 .4786

3.503 .479 .692 43. C06 .4786

J.f.80 .480 .700 •3.012 .u787

3.501 .484 .703 43.028 .4788

3.479 .4 76 .701 42.997 .4785

3.478 .478 .700 43. 002 .4786

3.493 .481 .706 43.021 .4661

3.489 .482 .702 43.014 .•660

3.500 .483 .704 43.034 .4662

3.490 .430 .701 43. 003 .4662

3.490 .482 .705 43.022 .4661

3.493 .481 .704 43.022 .4661

3.500 .483 .705 43.029 .4662

3.502 .479 .700 43.012 .4660

3.490 .479 .704 43. 024 .4661

3.485 .480 .700 43. 010 .4660

3.482 .481 .698 43.006 .4659

3. 490 .482 .705 43.013 .4660

3.481 .479 .708 43.011 .4660

3.470 .480 .697 42.994 .4785

3.518 .479 .699 43.021 .4789

3.491 .480 .700 43.C12 .4786

3.492 .484 .702 43.023 .4787

3.500 .482 .700 43. 020 .4787

3.481 .477 .703 43.010 .4786

3.550 .499 .740 43.099 .4793

3.504 .481 .696 43.005 .4788

2.971 .521 .713 42.410 .4745

3.488 .477 .703 43.301 .4786

3.494 .479 .695 42. 998 .4787

3.528 .483 .707 43. 048 .4789

3.481 .480 .692 42.938 .4784

3.485 .476 .691 42.988 .4784

3.510 .485 .705 43. 043 .4789

3.521 .487 .709 43.045 .4789

3.472 .475 .696 42.976 .4784

3.494 .477 .699 42. 987 .4784

3.523 .479 .690 ^3. 031 .4788

3.535 .483 .700 43.044 .4789

3.492 .481 .689 42. 996 .4787

3.479 .477 .698 43.307 .4786

3.487 .479 .698 42. 999 .4785

3.506 .479 .693 43. 003 . 4786

3.496 .482 .705 43. 019 .4787

3.483 .476 .693 42.995 .4785

3.494 .481 .694 42. 995 .^787
Table 7.4.1. Vaporizer Test 1

RUN DATE TEMPERATURE FRESSURE LNG FLOW RATE SAMPLING DELTA P VAPORIZER VAPORI

JMBER K MP A LPM RATE» SLPM KP A POWER.

100 2/22 111.0 .126 7.53 5.6 25. R 64.8

101 2/22 111.0 .12 6 7.57 5. 6 25 . A 10 2 2/22 1 1 1 • u .12 8 1.93 5.6 69

A 1 C 3 2/22 111.0 .12 8 3.90 2.0 2 5 . A 104 2/22 111.0 .128 3.86 5.6 25. R bk. 4 105 2/22 111.0 .128 3.86 5.6 25 . A

106 2/22 111.0 ,12 8 7.57 2.0 c S • A 107 2/22 111.0 .128 3.79 2. 0 70. R 14.3

108 2/22 111.0 .128 3.71 2. 0 7 C . R 15.6

109 2/23 120 . 0 .231 3.90 k.Z Zi. A 110 2/23 120.0 .229 3.82 k.Z 25. R 43.9

111 2/2 3 120.0 . 2 3 j 7.80 1.5 2 5. A 112 2/23 120.0 . 22 9 3 . 94 1 • 5 69. R 22.0

113 2/23 120.0 . 2 3 C 3.86 1 • 5 7 0 . A 114 2/23 120 . 0 .230 3.82 k.Z 7:

A 115 2/23 120 . 0 .229 7.80 k.Z 25 . A

116 2/23 120.0 .228 7.83 k.Z 25. R 59.8

117 2/23 120 . 0 .228 3.86 1. 5 25. A 118 2/23 111.0 .130 4. 05 2. 0 7C . A 119 2/23 111.0 .130 k. 01 2.0 70. R 15.6

120 2/23 111.0 .129 7.80 2.0 25. A

121 2/23 111 . 0 .127 4.09 5.6 45 . A 122 2/23 111.0 .12 8 3.97 5. 6 25 . R 64. 0 123 2/23 111.0 .126 3. 9k 5.6 25. A 124 2/23 111.0 .127 3.97 2.0 Zk. A 125 2/23 111.0 .126 7.65 5.6 26. R 63.6

126 2/23 111.0 .12 6 7.61 5. 6 2 5 . A 127 2/24 120.0 .23 0 8.02 1.5 25. A 128 Z/Zk 120.0 .23 0 3.82 k.Z 70 . A 129 Z/Zk 120 .0 .228 3.82 1.5 7& . R 10.2

130 Z/Zk 120 . 0 .22 8 3.82 1.5 7L . A

131 2/2I+ 120.0 • 22 9 3.90 1 .-5 6 9. R 9.9

132 2 /24 120.0 .229 7.83 k.Z 25. A 133 2/24 120.0 .228 3.82 k. Z 2 5. A 134 Z/Zk 120.0 .227 3.86 1.5 Zk. A 135 Z/Z<* 120.0 .228 3.86 k.Z 25. R 45.2

136 2/24 120 • 0 .228 7.87 k. 2 25 . R 46.9

137 z/Zk 120.0 .233 3.90 10. 6 70 . A 138 Z/Zk 120.0 .22 8 3 .97 k. 2 7C . A 139 z/z* 120.0 .229 3.97 1.8 69. A 140 Z/Zk 120.0 .228 7.83 10.8 25. A

141 Z/Zk 120.0 .234 3.82 10.6 25. A 142 Z/Zk 111.0 .129 3.82 10.1 25. A 143 Z/Zk 111.0 .125 7.72 10.0 Zk. A 144 Z/Zk 111.0 .130 3.86 10.2 7C . A 145 Z/Zk 111.0 . 127 3.86 10.1 25. A
Table 7 .4.1 . Vaporizer Test 1 (continued)

Number Time Mix N

2 CH

4

C

2

H

g

100 101

101

101

102

1118

1147

1203

1219

1239

555

5

5

1.225

1.242

1.240

1.239

1.227

64.536

84.653

64.631

84.657

84.704

9.545

9.391

9.408

9.412

9.469

102

103

103

10k

104

1305

1323

1338

1359

1415

5

5

55

5

1.224

1.209

1.213

1.219

1.217

84.713

84.216

84.209

84.447

84.502

9.441

9.661

9.656

9.571

9.522

105

105

106

106

106

1*»3*» 1451

1510

1526

1552

55

5

5 105

1.275

1.279

1.190

1.189

1.247

85.237

85.221

83.681

83.687

84.507

9.144

9.151

10.490

10.490

9.530

107

107

108

109

110

1617

16 34 1652

854

919

5

5

55

c

1.220

1.217

1.214

1.206

1.218

84.503

84.505

84.520

84.098

84.766

9.548

9.548

9.533

9.768

9.380

110 111

111

112

112

935

957

1016

1034

1055

5

55

55

1.219

1.223

1.220

1.209

1.207

84.758

85.114

85. 046

84.542

84.574

9.376

10.090

10.084

9.537

9.511

113

113

114

115

115

1151

1212

1230

1248

1305

5

55

5 105

1.201

1.203

1.208

1.214

1.251

85.519

85.529

83.762

84.906

84.623

9.802

9.786

9.940

9. 364

9.490

116

117

118

119

119

1327

1355

1420

1509

1437

55

5

5 105

1.217

1.215

1.200

1. 214

1.236

84. 514

84. 343

83.566

84.632

84.583

9.514

9.784

9.863

9.509

9.512

120 120

121

122

123

1534

1550

1609

1630

1649

5

5

5

55

1.261

1.265

1.209

1.214

1.208

87.825

87. 828

34.562

84.557

84.520

8.980

9.013

9.572

9.506

9.635

124

125

125

126

126

1707

1726

1741

1801

1817

5

5

55 105

1.190

1.214

1.214

1.208

1.241

83.549

84.457

84.497

84.732

84.609

10.300

9.466

9.432

9.499

9.496

127

128

129

129 130

913

931

946

1003

1019

5

55

55

1.175

1.202

1.199

1. 199

1.177

84.322

84.800

83. 794

83.786

84.120

9.605

9.425

10.159

10.159

10 .690

Heating

iCH, „ nC .hk „ Value Densi ty

3 8 4 10 4 10 MJ/m 3 gm/cm 3 3.504 .486 .705 43.032 .4789

3.530 .483 .700 42.990 .4786

3.537 .483 .701 43.000 .4787

3.501 .482 .709 42. 987 .4786

3.461 .463 .676 42. 941 .4782

3.477 .468 .677 42.949 .4782

3.714 .496 .705 43. 198 .4801

3.717 .500 .705 43.200 . 4802

3 .534 .500 .729 43. 090 .4793

3.532 .499 .728 43.075 . 4792

3.262 .441 .642 42. 671 .4762

3.273 .441 .635 42.672 .4762

3.474 .472 .693 43. 275 .4809

3.477 .473 .684 43. 270 .480 8 3. 534 .482 .700 43. 029 .4790

3.532 .488 .709 43. 056 .4790

3.526 .489 .715 43.059 . 4791

3.533 .491 .709 43. 057 .4790

3.688 .509 .731 43.248 .4680

3.462 .4 79 .695 42. 950 .4655

3.472 .482 .694 42.956 .4656

3.053 .233 .287 42.368 .4612

3.100 .246 .304 42.419 .4616

3.517 .486 .709 43.046 . 4663

3.515 .487 .706 43.037 .4662

2.774 .299 .405 42.292 .4602

2.776 .299 .407 42 . 290 .4602

3.600 .5 27 .763 43. 401 . 4693

3.393 • 461 .663 42. 665 . 4648

3.477 .473 .685 42. 964 .4659

3.540 .495 .720 43. 067 ..+ 665

3.818 .367 .472 42.985 .4660

3.955 .566 .652 43. 576 .4831

3.499 . 4 77 .699 43.010 .4786

3.492 .482 .695 43.000 .4787

1.769 .128 .037 41. 015 .4626

1.770 .124 0.000 40. 986 .4624

3.502 .473 .682 43.015 . 4787

3.527 .487 .709 43.042 . 4789

3.487 .471 .679 43.020 .4787

3.809 .477 .675 43.399 .4818

3.635 .503 .726 43.119 .4795

3.632 .505 .720 43.105 . 4794

3.451 .453 .657 42. 927 .4780

3.486 .476 .692 42.982 .4786

3.720 .493 .685 43.179 .4672

3.416 .470 .687 42.928 . 4653

3.644 .489 .715 43.306 .4685

3.655 .487 .714 43.310 .4686

3.164 .356 .493 42.696 .4653
Table 7 .4.1 . Vaporizer Test 1 (continued)

Run Number Time Mix N

2 CH C H

131 1043 5 1.207 84. 322 9.500

1 J 1 113 9 10 5 1 . ? ^ 4 OH OOi

132 1 7 n 1 5 1.231 84.756 9.373

133 1 2 1Q 1.209 84.147 9.778

13<» 12 3 7 3 1.205 a**. 077 9.520

135 13G6 5 1.209 84.443 9.498

1 Jb J. 3 0 c 1 ?1 5 OH i Q 1 1 137 1 3 5*+ 1 . ?i (. 1 1 LiH 84.6G9 9.504

138 1 h 15 1 . 224 82. 574 10.579

139 c7 1 . ? n ii 83. 838 12 .260

L<»0 1511 5 1.210 84.562 9.531

1529 5 1.218 RU ^ 7 Q 142 15 50 1.212 84.303 9.523

143 1607 5 1.214 84.577 9.519

144 1627 5 1. 196 84.528 9.553

145 1647 5 1.240 84.379 9.573

145 1705 105 1.238 84.557 9.527

C

3 H8 iC4

H 10nC

4

H 10

Heating

Value

MJ/m 3 Density

gm/cm 3 3.690

3.493

3. -.65 3.635

4.204

.521

.479

.480

.500

.445

.760

.698

.696

.732

.549

43.207

«» 3. 0 0 6 42.946

43.212

43.261

.4676

.4661

.4656

.4677

.4681

3.584

3.501

3.496

4.179

2.559

.517

.477

."79

.585

.143

.7U9

.695

.698

.859

0.000

43.133

43.006

43.008

43.92C

42.397

.4670

.4660

.4660

.4737

.4620

3.506

3.500

3.650

3.498

3.528

.483

.486

.526

.481

.484

.708

. 70 7 .785

.711

.711

43.035

43.024

43.214

43.026

43.062

.4662

. 4662

.4802

.4788

.4790

3.587

3.1.93 .494

.•82

.727

.703

43. 106

43.010

.4796

.4788
Table 7.4.1. Vaporizer Test 2

RUN NUMBERDATE TEMPERATURE

K PRESSUREMP A LNG FLOW RATE SAMPLING DELTA P VAPORIZER VAPORIZER

LPM RATE, SLPM KPA POWER, WATTS

182

183

18<4 185

3/01

3/01

3/01

3/01

111.0

111.0

ill.G

111.0

.127

.126

.124

.125

3.75

3.75

7.53

7.5 3

10.1

6. 7 6.6

10.0

33.

33.

27.

27.

196 3/01 111.0 .125 3.79 6.7 2t. A 187 3/01 111.0 .128 3.79 10.1 26. A 188 3/01 111.0 .126 7.57 10.0 26. A 189 3/01 111.0 .126 7.57 6.7 25. A 190 3/01 111.0 .125 7.57 6.7 26. R 77.0
Table 7.4.1. Vaporizer Test 2 (continued)

Run Tims Mix CH. Number 2 182 1010 5 1.243 84. 596

loo 1 U C O 1 • C 1 1

1 Q7 1 U O 1 1 U 0 1 m CH j 8h • 5 h 1

1 A/a 1 OH c OH • HU

1104A U liny 1 u t> 1 • 2h 8 OH i?U

185 1224 5 1.2Qh 8h.610

lob XCDC 1*239 8h #601

1lOfA 7 loll 17 11 c

Z> i one 1 o c J b 8h • 6 1

101 A A0 loco c io (.JO 0 H • OU 7 188 1344 5 1.201 84. 349

189 1359 5 1.177 84. 154

189 1415 5 1.176 84.179

190 1439 5 1.214 84.569

C

2

H

6 C

3 H 8

iC

4

H 10nC

4

H 10

Heating

Value

MJ/m 3 Densi ty gm/cm 3

9.479

9.461

9.544

9.737

9.543

3.491

3.498

3.492

3.513

3.509

.482

• 4 9t

.4 6C .463

.483

.710

. 7 •+ 4 .694

.653

.700

43.000

+ 3 . 0 51 43.001

43. C4C

43.019

.4787

• -»7 89

. 4788

.4789

.4789

9.503

9.393

9.491

9.628

9.597

3.504

3.537

3.496

3.590

3.582

.481

• 5 0 Z .436

.509

.509

.698

.728

.701

.758

.762

43.018

43 . 0 3 5 43.017

43.175

43. 167

.•+786

. 4789

. 4786

.h799

.4798

9.633

9.610

9.530

3.679

3.685

3.508

.542

.541

.481

.815

.809

.698

43.314

43.305

43.024

.4808

.4808

.4788
Table 7.4.1 . General Test 1

RUN DATE TEMPERATURE PRESSURE LNG FLOW RATE SAMPLING CELTA P PROBE VAPORIZER ACCUMULATOR

NUMBER K MPA LPM RATE, SLPM KPA POWER, WATTS BYPASSED

191 4/14 123.3 .248 4.24 5.0 35. R 59.7 NO 192 4/14 123.0 .258 4. 16 5.1 34. R 59.7 YES

i ~ j 123.0 • 24 8 4 . 1 ft i** H « Q*7 O H • QK ycc T t O 194 4 /14 123.0 . 254 4.01 CI-/ • X O -? • Dr\ CciO IN U

A J J

4&H //1 4. X "t it J 1 u • C J £ L fl 1 P • i. J? I K DC.»0 T t j

196 4/14 123.0 .247 4.01 5.0 35. R 62.8 YES

197 4/14 123.0 .248 4.05 5.0 35. R 62.4 NO

198 4/14 123.0 • 245 4 . n 5 5 . n pr c c • u IN U 199 <, /ll» 123.0 .251 4.0 5 5. 0 7R p D c • U I L J 20 0 4/14 12 3.0 • 252 4.09 5.4 p Tl j

201 4/14 123.0 .250 4.09 5.0 34. P 62.0 NO 202 4/15 123.0 .250 4.13 5.0 35. R 62.4 NO

20 3 '/IS 123.0 • 249 4.13 5.0 35 . Di\ 62.4 vpc T C d 20 4 4/15 123.0 .249 4.13 5,0 36 . s 62.8 NO

20 5 4/15 123.0 .248 4.13 5. 0 36 . s 62 .4 yf<; T C d 206 4/15 123.0 .248 4.24 5.0 34. P 62.8 NO 207 4/15 123.0 . 248 4.16 5.0 35. p 62.8 YES

20 8 4 /l 5 123.0 . 24 8 4. 16 7 • tl 7 c . •j " . co ft 9 A IN U 209 4/18 123.0 .25 0 4.16 5. 0 35 , 55.5 • CO

210 4/18 123.0 • 25 0 4.24 5.0 35 . 62.0 YES

211 4/18 123.0 .251 4.20 5.0 35. P 59.3 YES

212 4/18 123.0 .251 4.24 5.0 35. P 53.3 NO

213 4 /l 9 123.0 • 24 8 4.24 5.0 75 . pIN 57. 11 IN U

21*» 4/19 123.0 .24 8 4.24 5. 0 75 . Or\ 57.0. 7 f . II 215 123.0 . 248 4 . ? 4 en-/ . u 57 . 4 YCC

216 4/19 123.0 .247 4.24 5.0 35. s 57.8 NO 217 4/19 123.0 .248 4.24 5.0 35. p 57.8 YES

?1 A 4/1 Q ? U A It ? 4 5 fl O -> • p 5717 toA Kin INU 219 4/19 123.0 .24 7 4. 24 5.0 35 • C9 57 • ft IN U 220 4/1 9 123 . 0 • c » o 4 . ?4 enV . u c

J 5 7 A ycc

221 4/19 123.0 .246 4.13 5.0 35. P 57.8 YES

222 4/19 123.0 .247 4.13 5. 0 35. P 57.8 NO 223 4/19 123.0 .246 4.13 5.0 35 . 57.8 YES

224 4/19 123.0 .248 4.16 5.0 35 . 57.8 NO 225 4/19 123.0 • 246 4.16 5,0 35 . p 57.8 NO 226 4/19 123.0 • 248 4.13 5.0 35

p 57,8 YES

227 4/23 123.0 .247 4.05 5.0 35. R 57.8 YES

228 4/20 123.0 .249 4.01 5. 0 35. R 57.8 NO 229 4/20 123.0 .249 4.01 5.0 35. S 57.8 YES

230 4/20 123.0 .24 9 4.01 5.0 35. S 57.8 NO

231 4/20 123.0 .249 4.01 5.0 35. R 57.8 YES

232 4/20 123.0 .248 4.01 5. 0 35. R 57.8 NO 233 4/20 123.0 .248 4.01 5.0 35. P 57.8 YES

23*, 4/20 123.0 .246 4.01 5.0 35. P 57.8 NO 235 4/20 123.0 .249 4.01 5.0 35. S 57.8 YES

236 4/20 123.0 .248 4.01 5.0 35. S 57.8 NO 237 4/20 123.0 .246 3.97 5.0 35. S 81.8 YES

238 4/20 123.0 .246 3.97 5.0 35. S 81.8 YES
Table 7 .4.1 . General Test 1 (continued)

Run Number

Time Mix N

2 CH

4

C

2

H

6 19i

191

192

193

193

1131

1147

1218

1236

1316

6

5

66 106

.621

.622

.628

.627

.477

87.724

87.709

87.345

87. 388

87.822

6.633

6.622

6.800

6.743

6.665

194

195

196

197

197

1338

13 58 1417

1440

1459

6

g6

6 106

.623

.619

.621

.622

.481

87.771

87. 399

87.344

87.766

87.851

6.592

6.800

6.719

6.609

6.650

198

199

200

201

201

1525

1544

1603

1621

1638

6 v 6

66 106

.620

.625

.627

.620

.491

87.746

87.483

87.799

87.782

87.894

6.612

6.616

6.553

6.591

6.632

202

2 0 3 204

205

206

1104

1126

1149

1206

1228

6

g

66

6

.619

.614

.621

.629

.620

87. 755

87. 762

87.747

88. 309

87.773

6.611

6.433

6.624

6.279

6.602

207

208

208

208

209

1245

1305

1322

1340

1339

6

6

6 106

6

.621

.623

.619

.477

.618

87.637

87.749

87.776

87.838

87.726

6.607

6.613

6.590

6.641

6.667

209

2 0 9 209

210

211

1140

1257

1313

1405

1436

106

106

106

6

6

.475

.477

.477

.619

.605

87.818

87.793

87.872

87.715

88.802

6.666

6.668

6.637

6.673

5.897

212

213

213

214

215

1457

944

909

1000

1016

6

106

6

6

.618

.612

.476

.616

.621

87.725

87.692

87. 819

87.641

87. 940

6.612

6.646

6.644

6.686

6.413

216

217

218

219

220

1034

10 50 1109

1127

1142

6

g

66

6

.613

.616

.614

.613

.610

87.673

87.636

87.678

87.674

87.541

6.668

6.672

6.661

6.668

6.706

220

220

221

222

223

1259

1315

1331

1348

1404

106

106

6

6

6

.474

.476

.649

.613

.609

87.816

87.787

88.154

87.790

88.404

6.667

6.677

6.146

6.610

6.021

224

225

226

227

228

1422

1437

1453

951

1009

66

66

6

.613

.614

.615

.630

.611

87.688

87.686

87.518

88. 048

87.669

6.663

6.657

6.816

6.333

6. 655

Heati ng C_H 0 3 8 4 1 0 4 1 0 Val ue Densi ty MJ/m 3 gm/cm 3 4.016 .426 .581 42.566 .4541

l.H •r, 7 c u 0 P •La. H 7 7 e f coc • 50? Hl/, r> c 7 A • P ' 0Ll P i. P . H p H e H • c U P 7 7 c A A Ll P 7 7 1 u c; c

. H P P P

ii Li. 7 • H H C A ft Ll LlHe.P 7 7ft / 0 U

Ll c: c • H P P P H • U i i Ll 7 A He. D H

. H P o 0 4.011 .426 .578 42.552 .h539

• Dl7 LlHe.P 7 P 7 r . H P P H Hit?' ii Li fl £, P ft • b e U

LiHCP 7 7 1 « f f 1t. C C A • H P P O

o7 # QQQ 7 7 7 •

L.H e? RP C7Q • p #7 ii. He.P c;p ii. h 7i /. C 7 Q . H P 0 7

LH ft 7 P * U C C • p b 7

/,He.p e -( q b 1

p

• H P o b 4.007 .429 .586 h2.563 .h5h0

Hi 1 ' 0

ti & c. • HDP t, 7 A • boo L*. He.P 7 7 n /

u • H P P H

LH oft 1 P U 1 C L P A C O 1

• P 0 1

Llh P Ll 1 e . p h l u c; 7 Q . H P 0 P

i. n n 1 •

liH ?C 7/ C7Q • 1/17 Ll P c; /. e h e . P H D • H

/. c

P

7O q7 0»7 "Of QA7 ii P 7 . P D 7

LlH p c. Q n e . P p UL. c; 7 c

• H P 0 P 3.998 .433 .585 42.560 .4540

U 1 C. 7 « H H H • P 7 PLlH P k1 e . b 1 b • H 5 H

Zi fl ft 7 j. 9/,

• t> o 1

i. p ccc H e . P P P

L. Kli. fl • H P H U 7 Ant; HiC c. t. • . Do UPHe. 71Jl7Q • H P 1 7

7 doc; O • 7 7 P • He" • POP UPHe .

C.PHPLi Q Ll c; 7 Q • 4307

4.062 • hh7 .626 h2.6h1 .4547

Hl • nU

n 7 U O L 7 7 I 500 Ll P c; e * ne. p d iLl ^ Li ft • H P H U L - fl fl 9 . H C O .POO i* p c: 7 Li.c; 7 Q • H P O P

h • 0 1

• h 3h 5 Q ? h e . oti U 5 7 ft 7 Q 7 A .DUO ATA L.H P Ci 7 1 e . P ' 1

Ll C. Ll 1

• H P H 1 4.026 .430 .585 h2.6hh .4538

LlH ft 7 P • U O e

Li 7 Li • p 7 b Ll P f\ Q H e • D P 7L C i . ft • H P H U

fiH ft ft A U U OLl P 7 • H C ( C7Q • p r 7 uH eP f.1 7 . D 1 fii. c; 7 e • H P o D

HLv ft c. fl • U P U • HU 11 LH

c. 7 fl • p o u

(.9 C /. C He. PHP • H307 Ll C. 7 Q

7 707 O • f U r • H e «J . p o b LlH P 1 7 L. e . 1 f H . H P U H

if. 031 .429 .586 42.577 .4541

h. ft 7 ft • H 0 P coc • POP LlHe.P QQ? P j e

ii. C. Li P • H P H e

Li fl Li 1 ii 7 P COS • Poo LlH P ^ ft e • D P U •LlHPC 7J7Q

uH n c; r • U P I* U 7 1 • HOI ^ 7 A. • P f D LlH 7 ^ fl 7 e . D U o Li. • H

C.P L.H O7

Li P 1 • H el [TO fl • -> 0 uLlHe.7 C ft L. P U H Li. c; 7 c

4.034 .430 .582 42.594 .4542

H • U 0 J U 7 ft • H 0 U

c; c. • p bb IIHe.7 ADt, bU b . H 5 H H

1* ft 7 7 • HtO COT . P 0 c

/. P C Q 1 He . P y e • H p H e

Li ft 7 C j, 9(1 c a

• P 0 c H e . P p s5

ll c; /. P . H PH e

/»H • 11171 f /,7 c

• H 5 z> . p y i

/. o etc He. bbp /. C i. D

• H P H 0 4.030 .426 .586 h2.6h5 .4538

LH ft Li n « U H ULi 7 P coo .POO u P e c q h e • o P p li ^ l. n . H P H U

• C 3 0 • h 3 2 • 5 88 h 2 • h 3 7 .4530

3 • 9 7 6 • h2 p • 5 8 6 H 2 . 5 H H .4538

7 Q ? c; Ll U C

• H H v CQ7 uPh e . 7o 7^» p .4522

4.029 .427 .580 42.585 .4542

4.031 .431 .581 42.589 .4542

4.108 .406 .537 42.619 .4545

3.961 .434 .589 42. 462 .4531

4.047 .432 .586 *2.634 .4543
Table 7.4.1. General Test 1 (continued)

Run Number T i H1G Mix N

2 CH C H

229 1025 6 .607 87. 166 6.857

230 1054 6 .612 87.687 6.666

231 1113 6 .60* 87.826 6.571

232 1130 6 .610 87.728 6.633

233 1145 6 .625 88.660 6.120

234 1213 6 .613 87.692 6.657

235 1229 6 .625 89.171 5.930

236 1245 6 .612 87. 732 6.629

236 10 31 106 .477 87.820 6.665

236 1419 106 .477 87.815 6.669

236 1434 106 .477 87.806 6.677

237 1450 6 .594 87.516 6.904

238 1508 6 .672 91.750 4.564

Heating

1C.H, nC H, Value Density

3 3 4 10 4 10

gm/cm

L. ft R • HOP £ L. q u ^ ^ t; 4.C11 .435 .589 42. 591 .4542

3.977 .433 .590 42.547 .4538

4.012 .432 .580 42. 574 .4541

3.699 .385 .511 42.147 .4504

4* .. nu ?c ao • U? 7 COT • J o o 1l 1 J O D # i+5i+2 3.418 .372 .484 41.901 .4483

4.013 .433 .581 42.573 .4541

4.C21 .433 .564 42. 641 .4538

4.014 .435 .591 42. 646 . *538

4.015 .436 .591 42.649 .4539

4.036 .406 .544 42.617 .4544

2.475 .236 .301 4C.696 .4377
Table 7.4.1 . General Test 2

RUN OATE TEMPERATURE PRESSURE

NUMBER K MP A

239 4/21 123.0 . 248

H/tl 1 ? 7 fl 1 C O • U 241 4/21 123.0 .246

242 4/21 123.0 .248

243 4/21 123.0 .248

244 4/21 123.0 .247

H/ti lc j J • 9C UH AO 246 4/21 123.0 .247

247 4/21 123.0 .247

248 4/21 123.0 .246

249 4/21 123.0 .247

CPU p ^ n H / t. 1 7U.7 251 4/22 113.0 .243

252 4/22 113.0 .247

25 3 4/22 113.0 . 248

254 4/22 113.0 .250

H/ct • C H O 256 4/22 113.0 .245

257 */22 113.0 .245

258 4/22 113.0 . 246

259 4/22 113.0 .245

260 4/22 113.0 .244

261 4/22 113.0 .245

262 4/22 113. 0 .245

263 4/25 123.0 .247

264 4/25 123.0 .246

LNG FLOW RATE SAMPLING DELTA

LPM RATE, SLPM KP

3.97 5.0 35. 3.97 5.0 35. 3.97 5.0 35. 3.97 5.0 35. 3.97 5.0 35. 3.97 5.0 35. 3.97 5.0 35. 3.97 5.0 35. 3.97 5.0 35. 3.97 5.0 35. 3.97 5.0 35. 3.97 5.0 35.

4.16 5.0 35. 4.16 5.0 35. 4.16 5.0 35.

4.16 5.0 35. 4.24 5.0 35. 4.20 5.0 35.

4.13 5.0 35. 4.16 5.0 34. 4.16 5.0 35. 4.16 5.0 35. 4.16 5.0 35. 4.16 5.0 35. 5.22 5.0 35. 4.24 5.0 35.

PROBE VAPORIZER ACCUMULATOR

POWER, WATTS BYPASSEO

S 0.0 YES

S 0.0 NO

S 0.0 YES

S 0.0 NO

s a.o yes

S 0.0 NO

S 99.6 NO

S 98.6 YES

S 97.5 NO

S 98.1 YES

S 98.1 YES

S 98.1 NO

S 0.0 NO

S 0.0 YES

S 0.0 NO

S 0.0 YES

S 0.0 NO

S 0.0 YES

S 98.6 NO

S 97.5 YES

S 97.0 NO

S 97.0 YES

S 96.5 NO

S 96.5 YES

S 63.2 NO

S 62.0 NO
Table 7.4.1. General Test 2 (continued)

Run Number Time Mix CH

4

C

2H6

239

239

239

240

241

1040

903

1025

1056

1119

6 106

106

66

.592

.479

.480

.60*

.639

85.782

87.774

87.317

87.475

87.927

7.651

6.674

6.669

6.734

6.561

242

Z>*3 244

Zkk

245

1134

1149

1205

1326

13<»2

6

6

6 106

6

.608

.643

.606

.479

.608

87.724

87.576

87.652

87.794

87.696

6.654

6.769

6.668

6.672

6.665

246

Zi*7 248

21*9 250

1357

1415

1431

1453

1508

6

666

6

.610

.604

.611

.605

.603

87.627

87.713

87. 843

87.668

87.669

6.747

6.657

6.533

6.659

6.663

251

251

252

253

25*»

1151

1132

1207

1222

1242

6 106

6

6

6

.602

.477

.613

.600

.538

87.650

87.824

87.419

87.587

88. 876

6.706

6.658

6.598

6.703

6.667

255

256

256

257

258

1301

1318

1334

1359

1419

66 106

66

.599

.665

.477

.601

.603

87.574

88.716

87.838

87.698

87.798

6.744

6.627

6.643

6.660

6.601

258

259

260

261

261

1436

1519

1502

1559

1617

106

6

6

66

.480

.601

.598

.602

.604

87.864

87.731

87.495

87.715

87.688

6.634

6.643

6.767

6.656

6.672

261

261

262

263

264

1634

1651

1536

1153

1425

106

106

66

6

.481

.481

.597

.600

.600

87.855

87.822

87. 357

87.662

87.696

6.630

6.638

6.854

6.656

6.661

Mea xi rig

C 3H8iC

4

H 10 nC-H

H 1 U Va i Uc Densi ty MJ/m J gm/cm^

4.393 .602 .930 43.564 .4623

Llh nf>n u o u iHOl • P 0 0Ll 9 (.CO HC • DO C • H3HU

U (11 Q L. 9 7 • He/ • 500 /. 9 c. 7 q He. D 0 0

/. c 7 0

• HP O 0

1*. H 1 ft 9 • X D C • HHt ft a l. • ?OH iiHli? 7 n r 1 Ul i,cc;i

• H"5i

7 QC7 •5 • y P %3 1O7H 7 Q L. ft 9 t • P c 0 Hci H 0 u • HP 0 U 4.021 .421 • 573 42.569 .h5h0

LlH ft L. 1 • U H XL. -1 A • Hit) • P P H He. 1.0 c a 7 P 0 *5 Ll c: Lv L. • H P H H

LlH fl Ll a « U H 0 iHOd /.7ft CQfl L. 9 C.1 C, L. C Ll Ll • H P H H

L. n 7 7 Ll 7 9 • Hot K Q 1 •£1. Hc»9 C03Hft L. J, C 7 Q

L.h ft P ? • u c eL. 9 A COT • P 0 c Hti POD U C Ll 9 # H P H c 4.012 .424 .580 42.598 .4543

h • u i y • H C f con Ll P Cfl ? Hci ?Oc • H P HI

H • U 1

iHc? Ll 7 C • Off /. 9 C7C l, a 7 7 • H P 0 r u fl u c; H • U H P L. 7 1

• HOI • P 7 c

LlHe9 ft 1 ft • OIU LlCLl 7 • H P H 0

l. n "? q Ll 7 Ll • H 0 H co 9 fxHe9 ft 9 1 uU c • H PH 0

h .058 • h22 .562 H2.599 • h68h

H»l. nU CO? a . u 7

• H O X .

. 5^ A0 70

J. 9 . C /. 1 H C • D H X • ^ft H D aO nU

*t • X ~ 9 • H f c 7 0 7 (.?, Hci An? OUc u 7 n n • Hf UU

u * n ft a • H H X • DUX HL> C

P •

ftD ft-7 O7 •* HDOO Ll ft A A

O • O 9 O • c Ho • 401 i*. H X

1 • A07cft* P • H 0 X J 4.061 • h30 .573 42. 640 • h6A7

7 P Q .

LlH HL. Q9 UH 1 Q ft 7 X • 9 U 0 iHOOU Uft 7 ft n 7 p • H O u can • 50U L.P He. ftO037 ft • Hoi L. ft 7 Q3 H q 23 - u 7 n • 200 Ll 9 „ C Q C tCi P TM P

_ u ft A ~K O7 • QQQ 9 9 9 • U77 H c r ft 7 p . P f c i-Hci3HO 9 C A A • kft HOf7 Q7 4.015 .h3C .578 42.620 .4678

Hi Ul? • He/ L. P 7 • 7 O O ii. Hc»3f ? c; 7 a

y

iHOOc u ft A 7 H • 1 C U • HOD coc • SOP UPHe.. ftO AO LlH IH07U Ia ft Q ft Hil - nUcc? p • Her C7Q • 3/7 H C • 9 O J

. kft A P H * U C D

Ll 7 ft • H OU C 0 fi • 9 0 U

I* 9 C O 9 Ll ft A 7 • H D O 0 4.024 .429 .582 42.626 .4678

4.037 .434 .588 42.645 .4680

4.164 .439 .589 42.740 .4695

4.063 .433 .586 42.618 .4544

4.029 .431 .583 42.596 .4542
Table 7.4.1 . General Test 3

RUN OATt TEMPERATURE PRESSURE

NUMBER K MP A

265 4/25 123.0 .245 too Z> U 2b7 h/25 123.0 .245

26fl t/25 123.0 .245

269 4/26 123.0 .244

27., 4/26 123.0 .244

2 r 1 4/£0 123 . U .244

272 4/26 123.0 .244

273 4/26 123. 0 .244

274 h/26 123.0 .244

275 4/26 123.0 .244

? Q Q £ 7 :7 U / ? Q 1 C 0 • u 7 U U 300 4/29 123.0 .244

301 4/29 123.0 .244

302 4/29 123 . 0 .244

303 4/29 123. 0 .243

4/29 123. C .244

3 u5 4/29 123.0 .243

306 4/29 123.

.244

307 4/29 123. 0 .243

306 4/29 1^3.0 .244

309 4/29 123.

.244

31C 4/29 123.0 .243

LNG FLOW RATE SAMPLING DELTA LPM RATE, SLPM KPA 4.20 5.0 35. 4.20 5.0 35. 4.20 5.0 35. 4.20 5.0 35. 4.16 5.0 35. 4.16 5.0 35. 4.16 5.0 35. 4.16 5.0 35. 4.16 5.0 35. 4.16 5.0 35. 4.16 5.0 35. 4.16 5.0 35. 4.16 5.0 35.

4.16 5.0 35.

4.16 5.0 35. 4.16 5.0 35. 4.16 5.0 35. 4.13 5.0 35. 4.13 5.0 35. 4.13 5.0 35. 4.13 5.0 35. 4.16 5.0 35. 4.16 5.0 35.

PROBE VAPORIZER PROBE HEATE

POWER, WATTS POWER, WATTS

S 62.0 .1

S 62.0 .4

S 62.0 1.7

S 62.0 6.7

P 62.3 0.0

P 62.0 .1

P 62.0 .4

P 62.0 1.0

P 62.0 1.7

P 62.0 3.8

P 62.0 6.7

P 62.8 0.0

P 62.4 0.0

P 62.4 0.J

P 62.4 0.0

P 62.4 0.0

P 62.4 0.0

P 62.4 0.0

P 62.4 0.0

P 62.4 0.0

P 62.4 0.0

P 62.4 0.0

P 62.4 0.0
1

Table 7.4.1. General Test 3 (continued)

Number Time Mix N

2 CH

4

C

2 H6

265 1**3 6 .600 87 .630 6 .669

266 1*59 6 • 60 1 37.6 91 b • o32

267 1516 6 .597 87.705 b. 662

268 153* 6 . 601 87.69* 6 .679

266 1552 1 06 .-77 87.836 b.6*5

268 1509 106 .*73 87.318 6.672

269 1.26 6 .5 97 87.6 71 6.675

269 9*3 106 .*77 87.826 6 .663

269 959 1 u 6 .-78 87 .62* o .65b

270 10*8 6 .598 87.692 6.689

271 lit* 6 .593 67.*-9 6.825

272 1125 6 • 5 97 87.6 92 6.678

272 11*3 106 . -77 87.79* 6.693

273 1159 6 .599 87. 7U6 6.685

27* 1217 6 .599 87 . 7*b 6.673

275 1233 b • b J 0 87.71j 6 . 662

2 99 9 37 t • 5 90 87.5 95 b . 6 9b £99 922 106 .*77 87. 817 6.662

300 953 6 .533 37.680 6.635

3ul lull b .588 07.610 6.729

301 10 30 c .5 92 87.593 6.715

J U d 10*9 6 • 5 8 9 8 7.617 6.706

303 1108 6 .592 87.b75 d.678

3 U * 1125 6 .590 87.6*9 6.689

305 13*1 6 .537 67 .bOl 6.729

305 1319 106 .*78 87.79* o.679

3ub 1359 b . 590 67.6*6 6.698

j 0 7 1*18 6 .5 91 87.580 6.708

3^7 1*37 6 .592 87.61* b .o83

3„e 1*5* 6 .588 87. b66 b.68*

3o y 15-9 c .591 67.667 b.683

3lu 1531 6 .590 87.687 6.668

31u 15*9 106 .481 87.322 c . 6*8

Heating

C

3 H8

iC

4

H 10

nC

4

H 10 Value Dens i ty MJ/m 3 gm/cm 3

*. 033 .*29 .569 *2.*91 .*5*2

H.C16 .*29 .581 *2.*78 . *5*1

*.031 .*26 .578 *2 .*78 .*5*1

*.021 .*2b .580 *2.*76 .*5*1

*. 030 .*29 .58* *2. 52* .*538

*.C23 .*26 .561 *2. 52* .*538

*.C*7 .*3* .576 *2.*95 . *5*3

*.C23 .*3C .582 *2.52* ,*538

*.03b .*29 .578 *2. 525 .*538

*.019 .*27 .575 *2.*76 .*5*1

*.1*0 . **L .593 *2. 610 ,*552

*.02l .*29 .563 *2.*83 .*5*2

*.021 ,*33 .583 *2.535 .*539

*.010 ,*27 .57* *2.*68 ,*5*1

*.017 .*26 .578 *2. *73 .*5*1

*.C18 .*32 .578 *2.*73 .*5*1

*. 088 .*37 .595 *2. 5*5 .*5*6

*. 029 .*32 .563 *2.530 .*538

*.C36 .*27 .562 *2. *95 .*5*2

*.L56 . *3* .583 *2.52* .*5*5

*. 060 • *31 .58* *2. 530 ,*5*5

*.065 .*33 .590 *2.527 ,*5*5

*.b*3 .*3t .583 *2.*97 .*5*3

*.C56 .*32 .58* *2.511 . *5**

*. 070 .*31 .5 82 *2.529 .*5*5

*. 030 .*31 .589 *2. 539 .*539

*.051 .*3l .56* *2 . 510 ,*5**

*.067 .*37 .597 *2.5*9 .*5*7

* . 086 .*36 .59U *2.53* . *5*6

*.0*7 .*32 .56* *2.5Q5 .*5*3

* . o*0 .*32 .567 *2. 503 .*5*3

* . 0 * * .*3C .581 *2.*9* .*5*2

*. 032 .*33 . 5 8* *2. 528 .*538
Table 7.4.1 . General Test 4

RUN 0 a T t T tMPc R A T URE PRESSURE LNlj FLOW RATc SAMPLING C EL T A P PROBE VAPORIZER NEEDLE 1 JM6ER K MP A LPM RATE, 5LFM KF A FOWER, WATTS THPOTTL

27o */2u 1<:3 . j . c * * *. 16 5.0 35. S 62.3 YES Z77 */2o 1 *- 3 • y • 2 * * *. 13 5.0 35. S 62.0 YES Z76 */26 123 . u .2m * . 16 5. 0 35. s 62.0 NO

27 9 1+/26 123.0 . 2 * * * • 1 6 5.0 35 . s 62.0 YES

2oO */26 123.o • 2** * . 16 5.0 35. s 62.* NO

281 */27 1 2 3 . j . 2** *.16 5. 0 35. s 62.* NO 282 ,/27 lc3. u *. 20 5. 0 3b. s 62.* YES 283 */27 123. 0 .2*3 *. 16 5. 0 35. s 62.* NO 23* */2 7 123 •« . 2* 3 * . 1

5 . 0 35. s 62 . * YES £65 */27 123. a .2<w * . 1

5.0 35. s 62 .* NO

28o u/Z7 123.0 • 2 * * *. lb 5.0 35. s 62.0 YES 287 */27 123. u .2** *. 16 5.0 35. s 62.* NO 288 */27 123.0 .2-3 * . 16 5.0 35. s 62.

YES

269 */27 123.0 • 2** * . 1

5 • u 35 . s 62.* NO 290 */27 123.

.24* *. 16 5.0 35. s 62.* YES

291 */27 123. u .2*3 *. 20 5.0 35. s 62.* NO 292 */27 123 . u .2*3 *.20 5.0 35. s 62.* YES

311 5/j2 123 . j .2*2 *. 16 *. 9 35. p 62.* NO

312 5/02 123.0 .2*2 *. 1 3 *• 9 35s 62.* NO 313 5/02 123.0 .2*2 *. 13 *.9 35. s 62.* NO 3m 5/u2 it3 .0 .2*3 *. 13 5.0 35. s 62.* NO 3i£ 5/u2 123.0 .2*2 *.13 *. 9 35. s 62.* NO 31b 5/02 123. 0 . 2*2 *. 13 *. 9 35. s 62.* NO 317 5/02 123.0 .2*2 *.16 *. 9 35. s 62.8 YES

310 5/02 123. j .2*2 *. 13 *. 9 35. s 62.8 YES

319 5/02 123.0 .2*2 *.13 *. 9 35. s 62.8 YES

32a 5/02 123.0 . 2*2 *. 13 *.9 35. s 62.8 YES

321 5/02 123.0 .2*2 *. 13 *.9 35. s 62.8 YES
Table 7.4.1. General Test 4 (continued)

Run Number Time Mix N

2 CH

4

C

2

H

5 CIO 1 * 1 u

L.y • 570 a 7 7 1 k Of • f IP »- k k k ill 3 7 7 1*54 6

L liC

• P ^0 0 * • D f P k C Q 7 ci a 13 J 9 c

— q ~y • P 7 f

ft 7 7 1 1 Of • f LC b • 66**

0 7 CI 1 1 7

1 c oc IP c5 c • P 70 A 7 7 _ p DtDOl

oar COU 1 P 44 c k Q It • P 7 0 A 7 7 fi 1 k k 7 n

26- lou 6 lufc .*67 67.856 6. 6*t8

C 6 k ie>22 lob .1+83 87.630 6.o59

261 956 t .=95 87. 584 6.700

282 lull 6 . 596 87.715 6.672

213 lu26 o . 59* 67.666 6 . 6 6 u 28* 10*1 t . 5 9* 87.659 6.697

285 1 j5b c .^93 87 ,u92 b .b75

^85 1312 106 . 481 87.823 6.663

235 1327 10b .476 37.636 6.6*7

286 1342 6 .59* 87. 669 6 .697

287 1* u 1 c .596 87.691 6 . b79

268 1*16 6 .595 87.701 6.675

239 1*35 e . 596 37.o76 6.687

29 J 1* 5 u 6 .595 87.706 6.670

291 1510 6 . 593 87. 716 6.670

292 1527 6 .593 87.73* 6 . 651

292 15*3 lub • *77 87. 768 6.672

311 1*46 6 .55* 37.b30 6.70*

311 939 106 .478 87 .806 6.677

311 953 10b .47 5 87.809 b.669

312 11-2 6 .557 87.66J 6.71*

313 1122 6 .555 87.656 6.716

314 1140 6 .55* 87.655 6.727

315 1156 b .555 87.662 6.716

316 1215 b .557 87.690 6.692

316 1335 lUb .*73 87.815 6.666

317 1*07 b .558* 87.65* 6.720

317 1*26 fc .55* 87.683 6.701

316 1**3 6 .555 37.663 6.71*

319 15„1 b .556 87.625 6.719

320 1517 6 .55* 87.bbd 6.706

321 153* 6 .555 87.620 6.719

321 1550 b .553 87.b30 6.736

321 I6u9 lub .477 67.6u9 6 .666

321 1636 106 .*aa 87.876 6.622

C

3

H 8 iC

4

H 10nC

4

H 1Q

Heating

Value MJ/m 3 Density

gm/cm 3 4.014

*.u29

4.024

4.002

4.024

.429

.432

.427

.*26

.433

.579

.562

.576

.571

.57*

42.471

42.491

42.473

*2.*57

42.478

.*5*1

.*5*2

.*5*1

.*539

.*5*1

3.999

4.C14

4.063

4.015

*.032

.431

.*33

.441

.427

.429

.580

.581

.598

.57*

.580

42.502

42. 518

42.547

42.469

42.486

.*536

,*538

,*5*7

.*5<*0 ,*5*2

* • 0 4*

4. 033

4.C23

*.u25

4.G22

.426

.427

.431

.433

.428

.580

.580

.579

.581

.590

*2.*97

*2 .486

42.522

*2. 523

42.495

.*5*3

.*5*2

,*538

.*538

.*5*2

*.030

4.028

4.029

4.023

4.023

.425

.428

.431

.425

.426

.579

.573

.561

.582

.572

42.482

42.477

42.490

42.478

42.471

.*5*1

.*5*1

.*5*2

.45*1

.4540

4.015

4.065

4.078

4.028

4.031

.427

.432

.437

.428

.429

.581

.586

.597

.58*

.587

42.469

42. 556

42.557

42.531

42.535

.4540

.4540

.4545

.4538

.4538

4.049

4.046

4.053

4.052

4.054

.431

.435

.429

.430

.429

.589

.592

.583

.585

.578

*2.530

*2.536

*2,530

*2.529

*2.516

.4543

.4544

.4543

.4543

.4542

4.026

4.053

4.052

4.055

* .186

.430

.431

.429

.430

.431

.589

.585

.581

.583

.58*

*2.535

*2.530

*2.521

*2.529

*2.5*8

.4538

.4543

.4542

.4543

.4545

4.061

4.085

4.G64

4.032

4.017

.431

.431

.431

• *3l

.428

.580

.590

.586

.585

.578

*2.528

*2.55*

*2. 5**

*2.53*

*2.503

.4543

.4545

.4544

.4539

.4536
Table 7.4.1. General Test 5

n a t p T FHPFPA TIIPP Dp CCCllOC L Pi u » LU H KM 1 l

c a m pi t m r ncUt 1 T A P L. 1 A r PDnoc \lVMrft DHPT 7CD UKi £tK HUUun KcolUtNot

NUMBER K MP A LPM RATE, SLPM KPA POWER i WATTS TIME.S

c y o u y "7 ft 1141 U • HO 1 Q 7 3 0 t cd

29<» <«/28 112.0 .116 1.93 8.6 56. s 120. 15.0

295 W28 112.0 .116 1.93 5.9 56. s 79.0 21.8

296 W28 112.0 .117 1.89 12.2 55. s 160.0 10.5

297 W28 112.0 .116 1.89 8.6 55. s 117.2 15.0

298 <t/28 112.0 .117 1.93 12.2 55. s 160.0 10.5
Table 7.4.1. General Test 5 (continued)

Run Time Mi x No GH. Number 2 4

2 9 3 13 0 8 6 • 5 9 0 87.6 27 294 131*8 6 .590 87.678

295 1409 6 .591 87.690

296 1426 6 .539 87.670

297 Ikkl 6 .591 87.694

298 1459 6 .592 87.676

C H C H iCL H,

4 10 6.733 4.043 .429

6.690 4.031 .'32

6.672 4.037 .1*30 6.695 it. 035 .^31

6.676 4. 031 .427

6.682 4.036 .432

Heati ng

4 10 Value Density

MJ/m 3 gm/cm 3 .578 42.622 .4698

.579 42. 606 .4696

.580 42.604 .h696

.580 42.610 .4697

.582 42.600 .4696

.583 42.609 .4697
Table 7.4.1 . General Test 6

RUN DATE TEMPERATURE PRESSURE LNG FLOW RATE SAMPLING DELTA P PROBE VAPORIZER

JMBER K MP A LPM RATE, SLPM K p A POWER, Hi

322 5/11 123.5 . 222 4 . 16 4. 7 35. S 62.4

323 5/11 123.5 .222 4. 16 4. 7 35. S 62 .4 324 5/11 123.5 .222 4.20 4, 7 35. s 62.4

325 5/11 123.5 .222 4.16 4. 7 35

s 62 . 4 326 5/11 123.5 . 222 4. 09 4.7 35. s 99.1

327 5/11 123 . 5 .223 4. 13 4. 7 35. s 99.1

328 5/12 121.5 .222 4. 16 4. 7 35. s 99.

329 5/12 121.5 . .222 4.16 4. 7 35. s 99.1

330 5/12 121 .

.223 4.16 4.7 35. s 99.1

331 5/12 121.5 .223 '.16 4. 7 35. s 99.1

332 5/12 121.5 .20 2 4. 28 4. 5 36. s 62.4

333 5/12 121.5 .222 4.24 4. 7 35. s 62. 4 33^ 5/12 121.5 .223 4.28 4. 7 35. s 62.4

335 5/16 120.0 .276 4.16 5. 3 35 . s 62. 9 336 5/16 120.0 .276 4.16 5.3 35. s 62.8

337 5/16 120 . 0 .276 4 . 16 5.3 34. p 62.8

338 5/16 120.0 .277 4.16 5.3 34. p 62.8

339 5/17 120.0 .277 4.16 5.3 34. p 62 . 8 3*»0 5/16 120.0 .277 4.16 5.3 35 . p 62. 8 341 5/16 120.0 .271* 4.16 5.3 35. p 62.8
Table 7.4.1. General Test 6 (continued)

Run

lumber Time Mix N

2 CH4

C

2

H

6

C

3

H8

iC 4H,

322 1120 1% • 1 2 9 84 • 2 8 0 10.850 3 • 419 • 3 26 323 111.7 7 • 127 84 • 3 0 7 1 C • 841 3*397 • 325

32i» 1 21<» 7 • 127 84.2 74 10 • 84l 3 • 424 • 328 325 1306 7 • 133 84.331 10.830 3*401 .324

326 1511 7 • 140 84.319 10.831 3.390 • 324

Jcr • 134 84 .328 10*843 3*387 • 3 23 326 1106 6 7 ? 1 83*855 10*781 7 7 7C 0 • 0 0 P .322 329 11 34 8 • » t 1 83 . 857 10*780 7 71 • O C 1 330 1220 8 .721 83.81.9 10.790 3.336 • 321 331 1256 8 .709 63.851 10.790 3.338 • 322

332 1442 8

7 ? iT 0 0 • 0 1 J 10 8 0 0 3*348 .321

333 15 0 7 8 • 7 15 83*852 10* 799 3*333 o o c c 3 34 1556 6 • 7 1

2

83* 856 10*781 3*343 • 3 22 334 1623 8 .713 83.86<« 10,739 3.338 .322 334 1648 100 1.382 85.968 8*489 2.939 .517

3 34 1713 10 0 1 • 379 8^*953 8 « 5 0 3

7 QC: r> .516 335 1115 9 2*373 82*427 10 «5 7

1

3.320

J Jo Q 2 • 366 82* 363 10*600 3.336 .319

337 1222 9 2.369 82.386 10.590 3.322 .316

338 1252 9 2.365 82.31.2 lb. 590 3.323 .315

339 1327 9 2.361 82. 363 10.580 3.313 .311. 339 1352 9 2.362 82.363 10 .593 3.309 .313

3x0 1512 9 2.375 62.361 10 .619 3.328 • 3H.

3 1.1 151.1 9 2.376 82.369 10.610 3.328 .318

Heating

Value Density

nC.H,

„

4 10 iC-H,.,

5 12 nC-Hi

5 1 2 C,+

6

nu

2

3 MJ/nT 3 gm/cm

.71. i. .125 .111.0 0.000 .006 . 005 1.3. 931 .1.61 .TtZ . 12<» .1110 0.000 .009 .017 1.3.905 .1.61 .7«.6 .123 .1110 0.000 .009 .017 1.3.925 .1.61 .737 .122 .1120 0.000 .007 . 003 1.3.901 .1.61 .736 .121. .1130 0.000 .007 .015 1*3. 891 .1*61

.736 .123 .1120 0.000 0.000 .011. 1.3.891. .1.61 .730 .122 .1100 0.000 .C06 .318 1.3.613 .1.65 .732 .122 .1110 0.000 .006 .015 1.3.615 .1,65 .731 .122 .1120 0.000 .001. .01<. 1.3.620 .1.65 .732 .125 . 1130 C.000 .007 .313 1.3.632 .1.65

.731. .123 .1130 coco .006 .016 1.3.633 .1.65 .727 .122 .1110 0.000 .007 .312 (.3.619 .1.6% .731 .120 .1120 .001 .005 .017 1.3.621. ..6?

.72*. • 123 .1110 C . 0 0 0 0.000 . 316 1.3.620 .i.65 .705 0.000 0.0000 C.000 o.oco 0.300 1.2. 380 .1.59

.697 0.000 0.0000 0.000 a. ooo 0.00 0 i*2. 385 .1.59 .731 .122 .1130 .002 .C10 .316 1.2.921 .1.71 .7V2 .125 .1210 c.coo .Cll .316 1.2.962 .1.71 .73U .123 .1330 0.000 .011 .311. 1.2.953 .1.71 .728 .122 .1120 .087 .009 .306 1.3. 050 .1.71

.729 .125 .111.0 .087 .009 .305 1.3. 05C .".71 .728 .121. .1110 .073 .012 .315 1.3.018 .1.71 .732 .122 .111.0 .015 .006 .315 1.2.959 .1.71 .731. .121 .1160 0.000 .009 .019 1.2.939 .1.71
7.4.2. Confirmation Test Data

Table 7.4.2 lists the raw data for shipboard tests. The analyses

showing zero butanes content are boil off gas samples and have been omitted

from all statistical evaluations. Table 7.4.3 lists the second flow facility

test data. The runs corresponding to each test were:

Test A Runs 1 through 17

Test B Runs 18 through 39

Test C Runs 40 through 44

Test D Runs 4 5 through 58

Test E Runs 59 through 62

Test F Runs 6 3 through 71

Test G Runs 72 through 77. The heating values are

real gas values computed using the A.G.A. method [1]; liquid densities were

computed using the extended corresponding states method [3] . Two sets of

heating values and specific gravities are given for the flow facility tests.

The values listed with the operating variables are measured while those

listed with the composition are computed from the given composition.

184
Table 7.4.2. Shipboard Test Data

Run DATE TIME SAMPLE CflMPifr R AT r 1 tdC, Tf MP V/APOPT7FI JMBER SLPM MPA MPA K TEMP '

1 6/12 1655 L 17.500 .381 .232 114.6 -10.0

2 6/12 1705 G .567 .352 .108 114.6 -10.0

3 6/12 174C L 13.900 .421 .219 114.6 -30.0

6/12 1750 L 21.600 .432 .253 114.6 -30.0

5 6/12 1755 G .587 .432 .112 114.6 -30 . u

6 6/12 1855 L 6.900 . 312 .205 114.6 10.0

7 6/12 1855 L 8.900 .312 .205 114.6 10.0

9 6/12 1920 G .067 .492 .115 114.6 10.0

Q 6/12 1925 l_ 2 3.900 .492 • 2 6 7 114.6 X1 nu .. nu 10 6/12 1925 L 23.900 .492 .267 114.6 10.0

12 6/13 1715 L 12.500 .552 .294 114.6 10.0

13 6/13 1715 G 1.043 .552 .115 114.6 10.0

14 6/13 2100 L 13.900 .521 . 363 114.6 10.0

x ^ 6/13 210 0 1.043 .521 • 1 1

114.6 10.0

16 6/13 2215 L 14.900 .521 .253 114. 6 10.0

17 6/13 2215 L 14.900 .521 .253 114.6 10.0

18 6/13 222C G .587 .521 .112 114.6 12.0

19 6/13 2300 L 3.400 .521 .287 114.6 12.0

20 6/13 2 3 0 0 . 1 5• 521 • 1 1114.6 14.0

21 6/13 2350 L 32.300 .512 . 329 114.6 14.0

22 6/13 235C G .488 .512 .112 114.6 15.0

23 6/14 245 L 18.200 .481 .191 114.6 15.0

24 6/14 245 G .924 .481 .112 114.6 15.0

25 6/14 L 24. 900 .481 .315 114.6 15.0

26 6/14 hIO L 25.700 .461 .308 114.6 15.0

27 6/14 HlO G 1.023 .481 .112 114.6 15.0

28 6/14 445 L 24.200 .472 .274 114.6 15.0

29 6/14 450 G 1.023 .472 .112 114.6 15.0

30 6/17 lltC L 19.400 .421 .267 114.6 10.0

31 6/17 1142 L 19.400 .421 .267 114.6 10.0

32 6/17 1145 G .567 .421 .110 114.6 10.0

33 6/17 1200 L 22.000 .412 .239 114.6 10.0

34 6/17 1205 G 1.439 .412 .110 114.6 15.0

35 6/17 1210 L 14.100 .421 .225 114.6 15.0

36 6/17 1220 G .567 .412 .110 114.6 10.0
Table 7 .4.2. Shipboard Test Data (continued)

DATE TIME SAMPLE DA MCI ODCCC 1 Mr T C U D L rib ItHr \/A nnn T 7 r D ni iTl f~ -T- VAPUKlZtK OUTLET

NU Ho t

CI O M MDA MP A K TEMP °

37 6/17 1230 L 13.000 .412 .212 114.6 10.0

38 6/17 1235 G 1.221 .412 .110 114.6 20.0

6/17 12 40 L 10 c o U U

L. Q 9 • HP C one . c U P 114.6 20.0

4 u 6/18 1h55 L

4 a o n n

1 3 • c U U • 1

5 O C 115.0 20.0

4 1 6/18 150C G • 468 • ID 1 .10 5 115.0 20.0

HZ 6/18 1520 L 17.900 .h32 .205 115.0 20.0

43 6/18 1550 L 19.100 .501 .232 115.0 20.0

H H 6/18 1555 G • OOU * 1 U o 1 1 P . U

Of; n c u • u H P 6/18 1605 L C L « o U U

c; 7 ? ICO? 9 7 Q 1 1 P • U 9 0 ft H D 6/18 161C G

1 n 7 . 1 U f 1 1 p « u on n C U • U

47 6/18 1625 L 21.000 .532 .239 115.0 20.0

48 6/18 1640 L 25.600 .532 .253 115.0 20.0

H 9 6/18 I64O G Tan • JO? c; 7 9 1 AO • 1 U 0

4 4 c n live U

90. n v U 6/18 172C G £*. A A IVtl 1 no t X U 0

1 4 C fl 1 1 -> « U p n n c u • u

5 1 6/18 1722 L on <j fl fl » >cl % CSC 4 4 c n1 1 P . U p n n. c U • U

52 6/18 1735 L 22.300 .521 .219 115.0 20.0

53 6/21 1708 L 20.400 .412 .225 116.0 0.0

p H 6/21 1720 G

C fl 7 • lie 1 1 o . u c n n 90 • U

p 5 6/21 1720 L

o u inn c; 9 • hp c 1 lb . U U • U 6/21 1730 G lib / r 4 4 O

1 1 o . U nc ft 25.0

57 6/21 1735 L 6.200 .352 .225 116.0 0.0

58 6/22 2110 G .785 .501 • 108 116.5 25.0

CO5 p 6/22 211m L c j • 0 U U I&7H 4 4 C C 1 1 D « P

n n Dk nU 6/22 2125 I • 7 U 1 • CD o

1 4 A. C lib* 7n n OX 6/22 2230 G 1 (1(1 7 I o U o cni • ?U1 4 n a • 1 U 0

4 4 c, c 1 1 O . P

62 6/22 2255 L 24.300 .501 .239 116.5 0.0

63 6/22 2305 G 1.003 .501 .108 116.5 25.0

OH 6/22 2310 L

y l. inn . 7 U 1 J7Q 1141 AD . CPfl fl u • u 65 6/22 2325 L b H • ouu 97Q • CO? 1 A o • P u • u 66 6/22 2330 G 1.003 .501 .108 116.5 25.0

67 6/22 23*5 L 25.900 .501 .239 116.5 25.0

66 6/22 2*00 L 29.000 .501 .212 116.5 25.0
Table 7.4.2. Shipboard Test Data (continued) Composition, mol % Heating

Run jmber Time N,

2 CH.4 2 6

C 0 H 0

3 8 4 1 0 4 1 0 5 Value MJ/m 3 Density

gm/cm

1 1655 .114 83.827 11.565 3.457 .542 .496 0.000 43. 883 .4751

2 1705 9.724 74. 976 10.943 3.337 .533 .i»87 0.000 39.977 .4987

3 1740 .119 84.090 11.291 3.432 .560 .507 0.000 43.813 .4745

4 1750 .105 83.994 11.535 3.360 .527 .1+80 0.000 43.796 .4743

5 1755 . 993 O «J . o u II 11 . 575 3.214 • 479 . bbl oU .. nU nW ow 43. 314 • 4756

6 1855 .1*13 90 . <*01 6.762 1.934 .225 .220 .044 41.077 .4526

7 1855 .409 90.401 6.781 1.940 .225 .219 .026 41.064 .4525

8 1920 .209 83.762 11.553 3.442 .541 .494 0.000 43. 833 .4752

9 1925 .125 8%. 1<»2 11.286 3.378 .540 .495 .036 43.791 .4743

i. u . 123 84.196 X X . C fa H 3. 383 . 5b? . 4 9 3 . n bfl 43.781 . 4742

12 1625 2.879 97.080 . 041 0.000 0.000 0.000 0.000 36.694 .4262

12 1715 .118 85.200 10.511 3.161 .507 .457 .046 43.401 .4710

13 1715 .111 85.139 10.564 3.173 .510 .461 .042 43.426 . 4712

14 2100 .110 85.177 10.545 3.163 .507 .457 .040 43.408 .4710

15 210 0 .0 93 85.0 25 10 . 681 3.189 .511 • 459 .0 42 43. 475 . 4715

16 2215 .108 85. 140 10 .574 3.174 .508 .457 .040 43.423 .4711

18 2200 .112 85. 096 10 .574 3.184 . 525 .466 .042 43.453 .4714

19 23C0 .113 85.243 10.642 3.069 .464 .1*24 .044 43.322 .4704

20 2300 .110 85.071 10.591 3.197 .521 .460 .052 43.467 .4715

21 2344 2.751 96 . Q 8

j \j m v <J u .935 .2 34 0.000 0.000 0.000 37. 131 • 42 98

21 2344 2.729 96.096 .935 .240 0.000 0.000 0.000 37.143 .4298

21 2350 .110 85.141 10.555 3.179 .514 .1*59 .042 43.429 .4712

22 2350 .110 85. 170 10 .529 3.172 .516 .bbl .042 43.421 . 4711

23 21*5 .108 85.124 10.557 3.175 .516 .465 .054 43.450 .4713

2** 245 . 1 C 8 8 5. II 1* 10. 566 3.186 .511 . b 5 9 • 0 5 6 4 3. 451 . 4713

25 WOO .109 84.791 10 . 981 3.123 .502 .i»5l .044 43. 504 .4719

26 410 .110 85.090 10.577 3.200 .514 .4o2 .046 43.455 .4714

27 410 .109 85.108 10.574 3.191 .515 .b58 .046 43.447 .4713

28 i*t*5 .110 85.169 10.517 3.181 .513 .451 .050 43. 429 . 4712

29 450 .116 65.172 10 .508 3.183 .511 .b59 .052 43.424 .4712

30 1140 .029 82.571 12.317 3.850 .625 .560 .048 44. 534 .4798

31 1142 .013 82. 312 12.564 3.865 .628 .565 .054 44.631 .48 05 32 1145 .003 82.409 12.428 3.925 .621 .552 .062 44.624 . 4804

33 1200 0.000 82.511 12.396 3.897 . 628 .568 0.000 44. 549 .4798

34 1205 .029 82. 394 12.361 3.979 .631 .562 .044 44.622 .4805
Table 7 .4.2. Shipboard Test Data (continued)

Run Number Time N

2 CH

4

C

2 H

6 C3 H8

3536

37

38

39

1210

1220

1230

1235

1240

.002

.030

.031

0.000

0.000

81.390

82.773

82.525

81. 456

82. 569

13.540

12.303

12 .374

13.350

12. 325

3.835

3.751

3.847

3.938

3.859

39

39

39

4042

1430

1609

1918

1611

1712

.164

.166

. 353

.004

0.0G0

95.191

93.311

96.626

79.094

79.095

4.570

6.446

2.926

14.497

14.489

.075

.075

.095

4.831

4.838

43

4344

4546

1803

2147

1836

2116

2147

0.000 o.oco

.002

0.000

0.000

79. 184

79. 128

79.132

79. 049

79. 027

14.426

14.459

14 .443

14.498

14.511

4.817

4.830

4.842

4.864

4. 868

i*7 4849

5051

1622

1654

1727

1759

1828

0.000

.002

0.000

.003

0.000

78.955

78.920

78.864

78. 839

78.041

14.572

14.592

14.625

14. 539

15.548

4.871

4.887

4.900

4.863

4.830

5151

52

53

54

2037

2218

1858

1744

1819

0 .000

0.000

0.000

0.000

.003

79. 048

78.990

78.988

76. 310

78.215

14.516

14.550

14.550

15.091

15.165

4.857

4.872

4.871

4.993

5.051

5555

5556

57

2110

1852

2213

2038

2143

o.oco o.oco

0.000

0.000

78.407

78. 378

78. 372

78. 344

7t Ao . 5:? 7 z?

15.019

15. 034

15.025

15.113

14.923

4.993

4.996

5.016

4.960

4.950

5 7 5859

59

60

2242

1147

1330

140C

1450

.005

O.OCO

0.000

o.oco

0.000

78.607

76.675

77. 984

77. 996

77.931

14.921

14.809

15.292

15.282

15. 343

4.942

4.926

5.086

5.092

5.096

Composition, mol % Heati ng iC

4

H 10 4 1 U 5 Value Densi

MJ/m J gm/cm

.615 .559 .060 44.886 .4828

.573 .526 .046 44.396 .4788

.617 .561 .046 44.538 .4799

.631 .572 .052 44. 911 .4828

.622 .562 .0 64 44.568 .4799

0.000 0.000 0.000 39. 060 .4327

0.000 0.000 0.000 39.595 .4382

0.000 0.000 0.000 38.530 .4285

.795 .714 .066 46.020 .4909

. 797 .716 .0 64 46. 027 • 49 09 .799 .714 .062 45.991 . 4907

.800 .713 .070 46.019 .4909

.797 .716 .068 46.018 .4909

.803 .720 .066 46. 054 .4911

.801 .724 .070 46.064 .4912

.804 .724 .074 46. 092 .4914

.808 .724 .068 46.102 .4915

.805 .725 .062 46.111 .4916

.803 .719 .234 46.254 .4926

.792 .717 .0 72 46.331 . 4935

.789 .722 .068 46. 047 .4911

.802 .723 .064 46. 071 . 4913

.806 .721 .064 46. 074 .4913

. 838 .725 .074 46. 314 .4919

.793 .715 .058 46 . 328 • 4921

.806 .713 .062 46.268 .4916

.808 .725 .060 46.283 .4917

.809 .718 .060 46.288 .4917

.806 .712 .066 46.279 .4917

.764 .699 .066 46. 173 .4909

.775 .692 .056 46. 160 .4909

.790 .718 .084 46.184 .4903

.820 .732 .088 46.456 .4924

.814 .741 .074 46.445 .4923

. 818 .741 .070 46.463 .4924

3
Table 7.4.2. Shipboard Test Data (continued) Composition, mol % Heati ng Run

mbsr* Time N2 CH

4

C

2 H6 C,H

J RO 4 1 U nC d

H in Cc +

O Value Densi cy MJ/m gm/cm 6G 2145 o.coo 77. 929 15. 356 5.100 .815 .724 .076 46.459 . 4924

61 2150 0 . 000 77.912 15.347 5.131 .817 . 726 .066 46.467 . 4925

62 2223 0.003 77.857 15.375 5.135 . 324 .735 .074 46.499 .4927

62 2252 0.000 77.877 15.425 5.145 .823 .730 0.000 46. 430 .4922

62 2113 0.000 77 . 8 94 15.360 5.122 .8 22 .734 • 0 6 8 46.47 8 .4926

63 2324 0 . occ 77.953 15. 329 5.103 . 808 .727 . 060 46. 454 .4924

64 lu04 J .000 77.820 15 .401 5.136 . 824 .743 .076 46.516 . 4928

64 1502 0.000 78.125 15.199 5.C66 . 808 .733 .068 46. 388 . 4919

64 1659 0.000 77.773 15 .487 5.120 . 828 .728 .064 46. 508 .4928

64 2043 0 .000 77.909 15.349 5.113 .830 .728 .072 46.475 . 4925

65 1719 0.000 77. 869 15.376 5.121 .820 .731 .084 46.496 .4927

66 2301 0.C0J 78. 324 15 .431 5.164 . 355 .727 0.000 46. 043 .4696

67 1757 0.000 77. 874 15.380 5.110 .827 .730 .080 46.490 .4926

66 1828 0.000 77.625 15 .428 5.130 .818 .731 .066 46.495 .4927
Table 7.4.2. LNG Flow Facility Test 2 Data.

kUN JATc T I ML VAPORIZER TEST SECTION PANEL PRESS SAMPLING TEMPERATURE HEATING VALUE SPECIF]

NUMBER N U M 3 L

PRl SS t MP

MP A RA T L i SLPM K MJ/M GRAVII

1 3/-9 1-25 1 . 3*2 .2*9 12.26 12*. * *3.192 .650

2 3/-9 1j25 c . 3*2 .256 13.56 12*.* *3.192 .650

3 8/-9 llOo 1 .3** .257 12. *2 12*.* *3.192 ,650

-» 6/09 1100 2 . 3** .2** 12.6* 12*.* *3.192 .650

5 8 / o 9 13 2C 1 . *59 .307 lb. 59 125. 2 *3 • 211 .65 0

6 o/u9 1525 1 .*59 .232 18.19 125.8 *3.211 .650

7 8/ J9 1525 2 .*59 .216 18.53 125.8 *3.211 .65 0 6 8/09 lo 00 1 .*5l .265 19.00 125.2 *3.192 .650

10 6/09 1615 1 .*51 . 251 19.1* 125.* *3.192 .650

13/ j 9 1 6 1

2 . *5.230 15.13 12 5.* * 3 . 1 92 .65 0

12 3/u9 lo30 1 . **1 .2*8 19. *2 12*. 3 *3.192 .650

13 8/09 lb 3o 2 .**1 .220 13. *3 12*.

*3.192 .650

1* 3/ j9 16*5 1 . **3 .2*3 19.1* 12*. 7 *3 . 192 .650

15 6/09 lb*5 2 . **3 .222 13. *3 12*.*3.192 .650

18/ j 9 17 j 0 . ** 9 .256 19. *2 12* . 8 *3. 192 .65 0

17 8/o9 I7uu 2 .**9 .228 15.13 12*.

*3.192 .650

18 8/10 10 30 2 . *6* .291 18.29 132.7 *3.528 .658

19 8/1- Hub 2 .*37 .266 20. 92 132. 6 *3.5*6 .658

2 0 8/ 10 113L 2 . *7b .2*9 21.7* 131.9 *3.5*6 .658

21 8/10 li«»5 2 • <*97 .2 6* 22.33 133.1 *3 . 5*6 .658

22 3/10 120u 2 .*93 .293 22.68 132.8 *3.5*6 .658

23 3/10 122u 2 ,*61 .261 22.68 132.* *3.5t»6 .658

c* 8/10 1230 2 ,*61 .281 21.5* 132.* *3.528 .658

25 6/10 12*5 2 . *81 .302 22.68 132.* *3.528 .658

26 8/10 13 0 0 2 .'8 7 .267 22.68 132.6 *3 • 528 .65 8

27 8/10 133u 2 .*79 .272 21.26 132.5 *3.5*6 .658

26 6/10 1* 0 b 2 .*80 .280 22.68 132.5 *3.5*6 .658

29 8/10 1*15 2 .*7* .27* 22.68 132.* *3.5*6 .658

30 8/10 1430 2 .*92 .285 22. 39 133.1 *3.5*6 .658

3 1 3/10 1**5 2 . *8 9 .263 2 2. 39 1 33 • C *3 . 5 < 6 .658

32 8/10 1530 2 .522 .336 13. *9 13*.*3.621 .660

33 8/lu 15*5 2 . *61 .286 12.9* 132.3 *3.677 .660

3* 8/10 iDUU 2 ,*81 .288 12.9* 132.1 *3.639 .658

35 3/10 1615 2 .*93 .320 13.81 132.6 *3.639 .658

7 £ J b 8/10 16 30 2 . *8 9 • 310 13. 65 132.5 '3.639 C C Q

• b p 8

37 8/10 16*5 2 . *86 .300 13. *5 132.* *3.639 .658

38 8/10 1700 2 . *9i .298 13.29 132.7 *3.639 .658

39 9/10 1715 2 ,*89 .303 13. *5 132.6 *3.639 .658

*0 8/11 IIhC 2 .*9* .280 19.** 122.8 **.25* .690

*1 8/11 1155 2 .*35 .255 16. 03 118.6 *3.863 .680

*2 8/11 1210 2 ,*13 .2*7 16.03 115.7 *3.695 .680

*3 3/11 1225 2 .*98 .291 16.03 122.8 *3.733 .680

** 8/11 12*5 2 .*81 .25* 15.09 121.8 *3. 733 .680

1*5 8/11 1*00 2 .*68 .233 9.06 122. 3 *3.8** .680

*D 6/11 1*00 1 .*68 .25* 9.60 122.3 *3.8** .680
Table 7.4.2. LNG Flow Facility Test 2 Data (continued).

RUN OAT£ TIME VAPORIZER TEST SECTION PANEL PRESS SAMPLING TEMPERATURE HEATING VALUE SPECIFIC

NUM3ER NUMBER PRESS, MPA MPA RATE.SLPM K MJ/M GRAVITY

47 8/11 1430 2 • 485 . 264 V . D J ICO 1 T 4 3.826 .680

48 8/11 l<+3u 1 .485 . 264 9.47 123.4 43.826 .680

49 8/11 15 0 0 2 . 477 .257 9.69 122.7 43.826 .680

50 8/11 15GC 1 .477 .264 9.60 122.7 43.626 .660

51 8/11 153C 2 .478 .25u 9.69 123.5 43.882 .680

8/11 15 3 o .47 8 .264 10 . 62 12 3.5 4 3.882 • 6 8 0 53 8/11 lo45 2 .45 3 .212 5.16 121.1 44.124 .690

54 8/11 1645 1 .453 .267 6.03 121.1 44.124 .690

55 8/11 17 ju 2 . 437 .189 5.00 120.1 44.124 .680

56 8/11 170b 1 .437 .210 5.95 120.1 44.124 .680

57 3/11 17 31 2 . 454 • 22 0 4.58 121.6 44.180 .682

5o 8/11 1731 1 .454 .24C 5.66 121.6 44.180 .682

59 6/12 142C 1 .463 .460 18.95 117.3 44. 049 .717

6 0 8/12 1435 1 .459 .448 18.95 116. 8 44.049 .717

61 8/12 1*45 1 .483 .480 19.38 118.3 44. 049 .717

8/12 14 55 j_ . 462 .452 19.09 117.0 44 .0 49 .717

63 8/12 15 j 5 1 .451 . 216 16.67 115.9 44. 049 .717

64 8/12 1505 3 .451 .216 15.61 115.9 44. 049 .717

65 8/12 1515 3 .450 .229 15.13 115.9 44.031 .717

66 8/12 1525 1 .467 .226 16.63 117.6 44.031 .717

b7 8/12 15 25 3 .467 • 229 15.94 117.6 44.0 31 .717

08 8/12 1535 3 .469 .23* 15.81 117.8 44.031 .717

69 8/12 1545 1 . 461 .220 16.83 117.5 44 . 068 .717

7 j 8/12 1545 3 .461 .220 15.13 117.5 44.068 .717

71 8/12 1556 3 .454 .212 15.13 116.4 44.068 .717

72 6/12 1650 1 .473 .236 17.79 117.5 44. 198 .716

73 6/12 1650 3 .473 .216 15.13 117.5 44.198 .716

7* 8/12 17j5 1 .477 .222 16.35 117.9 44. 198 .716

75 6/12 17x5 1 .46 8 .213 16.35 117.5 44.198 .715

7c 8/12 1715 1 • 4o 8 .248 17.20 117.5 4* . 198 .715

77 8/12 174c 3 . 4*5 .210 1 h. 6h 115.6 44. 198 .715
Table 7.4.2. LNG Flow Facility Test 2 Data (continued).

Run NumberInte- grator

MN

2 CH

4

C

2

H

6

C

3 H 8

i r H

1 A 0 > CO c 65, 017 11.991 2. hIh . 223

2 A 0 Lu u o h , o27 12.169 2. h2h .225

2 B . bb9 8b . 839 12.139 2.h31 . 220

3 A 0 00 u 65. 399 11. o7* 2. 3h7 . 221

3 B 0 .coo 65. h6C 11.647 2.34b .216

* A w id jU o 3. 228 13.h2h 2. 701 . 252

it B 0 .too OH. 9bH 12.090 2.h33 .223

5 A b .000 6-*. 5 75 1 2

.

3ho 2 . h 8 j .233

5 B 0 .00 0 8h. 5 6 0 12.367 2.h83 .227

6 A 35. C 7 C 11.968 2.333 .226

6 3 .006 85. C65 11.95b 2.397 . 221

7 A U .000 34. tn3 12.319 2. h82 .217

7 A J ,000 8b. 672 12.299 I. h73 . 213

7 a il . Ob J 686 12.2o2 2.481 .211

8 A u » w 0 o 8 h. 3h6 12.531 2.514 .236

8 B 0 > 0 u u 3-. i 726 12.263 2.470 . 215

8 B 0 . Ou 0 8 h. 375 12 . 522 2.503 .231

lu A u .ujC 63. 763 13.007 2. 599 . 246

1 j 3 J .00 b 83. 775 12 . 987 2.606 .2h1

11 A u • 0 o 0 8h . 75 9 12. 3o5 2.379 .217

11 B 0 .coo Oh, 68 0 12.276 2.h5d . 221

i<: A • b b D c h • 911 12.073 2. h25 .227

12 B u 0 0 0 6b. 9h3 l2.«54 2.422 . 221

13 A ,00 0 flt. 695 12

.

2d0 2.469 .223

13 A .00 b 6b

.

68h 12.268 2.470 . 224

13 3 w I b b 0 OH. 728 12 .232 2.475 . 222

13 B U > u b L 8b. 697 12.2b7 2.h7h . 222

i*» A J . Co C 8h. 911 12. Odu 2.h27 . 227

8 U . b U 0 6h . 955 12. 05b 2.419 . 22h

15 A c • COO 6 5

.

06 5 11 . 9b 3 2. h28 .235

15 B it li/lil 35 . 066 11.696 2.43b .230

lc A u • 000 6h . 656 12. 265 2. 464 . 231

16 B j .00 0 6b, b65 12.266 2.458 . 22d

17 A b • b 0 c 3h. 606 12.262 2.537 .225

17 3 » b L b 6h, 6h2 12.259 2.532 .222

16 A U . Ou o 3 3

.

916 12. dob 2.575 . 2h1

16 B 0 .000 83. 960 12.855 2. 582 . 240 19 A - . (J b b 83. 9h6 12.850 2. 573 . 236

19 3 . tb 7 63. 998 12. 848 2. 562 .230

20 A 0 . b U b 63 . 8h9 12.908 2. ?97 . 245

20 B 0 . C 0 b 83. 906 12.895 2.586 .236

21 A u > U b J 6b. 1*8 12 . 877 2. mo . 224

21 3 j . b b b 6h. 19b 12 . 855 2.hj2 .217

£2 A j ,o0u 83. 914 12.636 2.595 • 2ho

22 8 ,004 03. 970 12.839 2.582 . 239

23 H j • b U b c3 . 9j9 12.878 2. 569 .242

23 8 • b b 6 o3. 9h6 12.a77 2.566 .236

2b A u • U 0 J 33. fl 3 5 12.932 2. d7h . 2h 0 2b A . b 0 5 83. 822 12.947 2.589 . 238

Zk d b J 5 o3

.

895 12.939 2. 57b . 234

Composition, mol % Heating <-

- f. Value specific

nC.H, n iCVH 1? nCVH,- C,+ . Gravity

4 10 5 12 5 12 6 \

MJ/m3

. 138 .037 . 0 h8 .08.5 4 3.147 . 6h7

.16 6 .036 . jh7 .082 43.235 . 6b

3

.18 9 . L 3 5 . J H 7 • 0 92 43 . 2 0 7 . 6 b 8

. 186 .037 . Obo .063 43.018 . 6b5

.135 .030 . 0 h 6 .072 42.97b . 64b

.211 . ; hz .052 .090 h3. 786 .653

. 191 .034 . 0h9 .077 h3. 179 • O H 3 .195 . 0 3t , Q b,9 .0 8b b3 , 306 .650

.195 .035 • 05 0 . 0 33 h3. 305 .650

.187 .037 . jh7 .082 43.123 . 647

.188 .031 • 0 h 7 .091 4 3.129 . 6b7

.166 .034 .044 .076 43.255 . 6b9

.135 .033 • 0 b b .0 76 b 3. 244

. 185 .031 . 0 4 5 .079 b3. 2bl . 6b9

.196 .039 . j 5 0 .087 43. 389 .651

.136 .030 . 045 .065 43. 211 .6b3

.199 .03b . 05o .08o b3. 366 .651

.205 • 0 4 1 .051 .0 89 b3 . 596 .655

.206 .031- . b 5 b . 09b b3. 595 . 655

,18b .036 . Onb . 07o 43. 19b . 6b3

.193 .033 . Jp 0 .090 4 3 . 26 5 . 6h9

.169 .039 . J h8 .083 h 3 . 1 3 2 . 643

.192 .031 .050 . 0 87 4 3. 174 . oh7

. 19C . 03fc . 0h7 .061 43. 253 . 6b9

. 191 .037 . 0b6 .080 b3.256 . 6h9

.192 .032 . U b b .075 h3.233 .6b3

.192 .031 .0b7 .090 43.262 . 6b9

.139 .037 • Oh 7 .082 4 3. 13 3 . OH 8 .191 . 0 3b . U H O .076 b3. 153 . 647

.195 .039 . J b9 .086 h3. 155 . 6b7

. 19h .037 . jb9 .096 b 3. 166 .647

.193 .038 .049 .08b 43.277 . 6b9

• 1 92 .033 . 0 h 7 • 09b b3. 269

. 192 .036 .045 .076 43. 295 • 6 5 0 .193 .031 . 0h6 .075 43.275 . 6h9

.204 .057 . 052 .091 43.559 . 65b

.20b .037 . 0h3 .079 43.508 . 653

.200 .056 .050 .087 b3 . 538 .654

.202 .037 . 042 .075 43. b73 . 653

.20b .056 .052 .090 43.53b • 654

.206 .036 . 0h7 .086 b3 . 537 . 65h

.187 . u 55 .03 6 .062 b3.375 . 651

.186 .03b .0h2 .075 b3. 360 . 651

.205 .058 .053 .092 b3.571 • 65h

.204 .035 . 0h7 .030 43.506 .653

.203 .059 • 0 5 2 .090 b3 . 558 .65b

.205 .037 . 0b6 .081 43.5C8 .653

.202 .057 .051 .089 43.571 . 65b

.202 .057 . 052 .090 b3.532 . 65h

. 202 .035 • 0 H H .072 b3. 506 .653
Table 7.4.2. LNG Flow Facility Test 2 Data (continued), Composition, mol % Run Inte- Number grator

C

2

H

6 C3

H 3 iC

4

H 10nC

4

H 10iC

5 H 12

nC

5

H 12

C

6 +

Heati ng Value

MJ/m 3

Speci fic Gravity

2h a C t 5 63.863 12.9M1 2. 576 .238 .201 .036 . 0m6 .07m m 3 .516 .653

25 A u > k> u u o3 . 9 J 7 12.912 2 . 5m8 • 2m0 .201 .055 • 05 0 .0 87 m 3 . 5<*3 • 65m

25 B , Gil o3. 931 12.9u2 2. 562 . 236 .203 .036 • Omm .07m m3. m95 .653

26 A 0 .00 0 63. 865 12.90m 2. 58m . 2m3 .203 .056 . 053 .091 m3.578 • 65m

2o B 0 .000 83.931 12.687 2.571 . 2m0 . 20m .037 . 0m7 .08m m3.522 .653

27 A « »C0G 63. 77m 12.96m 2.612 . 2m5 .205 .058 .053 .091 m3.613 .655

27 B . L u <• 83 • 83 5 12 . 961 2.602 • 2m 0 .207 .037 • 0 m5 • 0 7m m 3 . 5 m 6 • 6 5m

28 A J .00 0 63.83m 12.921 2.596 .2h3 .20m .059 . 052 .090 m3.589 . 655

28 a 0 COO 83.89m 12.92m 2.587 . 2mC .20b .035 . 0m6 .070 m3.517 .653

29 A .00 7 o3. 8m 8 12.9m0 2.596 .2m5 . 205 .057 .052 .090 m3. 592 .655

29 B .009 63.856 12.9m7 2. 596 .236 .203 .03m . 0m6 .073 m3.525 .65m

3 0 A J 0 0 0 83.85 7 12.920 2.586 . 2m

.202 .057 • 051 • 0 8 8 m3 , 5 72 • 65m

30 a 0 .000 83.918 12.907 2.587 .237 , .20m .03m . 0m2 .071 m3. 506 . 653

31 A OU 7 63. 822 12.921 2.6J0 . 2m5 .20m .060 .052 .090 m3.591 .655

3i 3 013 83.881 12.913 2.568 .239 .205 .036 . 0m6 .079 m3. 525 . 65m

32 A 0 .000 63.020 13.5m9 2. 7m6 .257 .216 .061 .055 .096 m3. 891 .660

32 A u .000 83.028 13.552 2. 735 • 2 5m .216 .062 .056 .0 97 m3 . 887 • 66 0 32 3 0 .000 o 3. 1 J m 13.529 2. 732 .250 .216 .OmO .050 .079 m3. 816 .658

32 8 006 63.063 13.5m8 2.737 .252 .216 .035 .0m9 .093 m3. 8m0 .659

33 A .01-* 83. 715 13.008 2.607 . 2Mb . 205 .059 .053 .092 m3. 623 .655

33 a .021 83. 765 12.997 2.612 .237 .207 .035 .0m5 .081 m3.561 . 65m

3** A ( U J 1 63

71m 13.030 2.600 . 2m5 .207 .056 .0 52 .0 90 m3 . 62 0 .655

3m a 009 83. 750 13.015 2.618 . 2m0 .205 .032 . 0m3 .089 m3. 581 .65 m 35 A 0 ,000 63.678 13.036 2.630 . 2m6 .206 .059 .053 .091 m3.6m9 .656

35 a 013 83. 73 6 13.021 2.619 .2m2 .208 .035 . 0m6 .078 m3.576 ,65m

36 A ,o06 63.770 12. 968 2.605 .2m5 .20m .059 . 052 .090 m3. 608 .655

oo B 0 .000 8 3 . 8m 0 12.965 2.602 . 239 .205 .037 . 0 M 1 .0 66 m 3 . 5 3m • 65m

37 A 00 6 63. 8m0 12.915 2.591 .2m3 .205 .057 . 052 . 090 m3. 579 .65m

37 B .006 83.676 12.922 2.593 .2m0 .205 .033 . 0m7 .078 M3.530 .65m

36 A w 0 j 0 63. 798 12.960 2.59m .2m3 .205 .057 .052 .091 m3.600 .655

38 B 006 83. 8m5 12.935 2.607 .2m1 .207 .036 . Omm .081 m3. 5m9 .65m

3 9 A 011 6 3.690 12.860 2. 597 . 2m3 .203 .057 .051 .086 m3 .560 • 65m

39 a 01m 83. 9m6 12.853 2.579 .238 .20m .037 .0m2 .086 m3. 511 .653

<*ii A 1 239 6J.33m 1m.7m7 2.966 .276 .23m .Omm . 059 .102 m3.915 .673

til a ll 60 6 80 . 059 1m.68m 2.958 .27m .23m .OhG .053 .090 m3. 722 .67m

Hi A 1 978 79. 78m 1m. 591 2.931 .279 .233 .Ohm .059 .101 m3.571 .675

Ml a 1 < 62 7 80.086 1m. 633 2.952 .276 • 2 35 • 0 MM • J 52 • 0 96 m3 . 71.67m

m2 A 1 .275 60.325 Im.771 2.921 .276 .231 .0mm .058 .100 m3.876 .673

h2 a 1 ,6h3 8J.C6m Im.681 2.939 .270 .23C .OmO . 0m9 .083 m3.675 .673

h3 A 1. 2m 0 60. 366 1m. 712 2.961 . 282 .23m .0m5 .059 .102 m3. 908 .673

m3 a 1 ,596 80.103 1m.6m2 2. 961 .27m .235 .0m2 .051 .095 m3. 725 . 67m

MM A 1 ,9lH 79.523 Im.872 2.973 .282 .23m • Omm .058 .100 m3.701 .677

MM B 1 581 79.818 1m. 921 2. 988 .277 .23m .Omm . 052 .0 87 m3. 817 .675

h5 A 1 ,176 80.352 1M.779 2.973 .282 .236 .Omm . 059 .101 M3.957 .673

m5 B 1 ,506 80.116 1m. 729 2.961 .27m .23h ,0h3 . 050 .088 m3. 771 ,67m

M 6 A 1 902 79.803 1m.6m5 2.935 .280 .232 • Omm .058 .101 m3.616 .675

m6 B 1 ,570 80.107 1m.679 2.951 .276 .235 .Omm . 052 .086 m3u. 733 ,67m

h7 A 1 ,159 80.222 1m. 912 2.972 .285 .237 .0m6 . 062 .107 MM. 019 .67m

h7 a 1 >m88 79.967 1m. 858 2.980 .279 .235 .0m5 .053 .097 m3.850 .675

h8 A 1 20 h 6 0

3m u 1m. 796 2.9m0 .261 .235 .Omm .059 .102 m3. 933 .673

i
Table 7.4.2. LNG Flow Facility Test 2 Data (continued) Composition, mol % Inte- grator

N, CH, C

2 H6

C

3 H 3 iC

4

H 10nC

4

H 10

iC

5 H 12 nC

5 H 12

C

6 +

Heating

Value MJ/m 3

Specific

Gravity

A 1. 202 60 . 307 14.798 2.975 .276 .234 .045 .059 .102 43. 953 . 674

HO a 5^ . v.79 14.723 2.956 .276 .235 .042 .052 .092 43. 764 .674

h6 B 1 54 7 80, b7t 14.727 2.962 .275 .233 .044 .054 .087 43. 760 • 674

H 9 A 1 1/ C 0 J , CIO 1 4 . 8 4 2 2.975 .283 . c 0 p • 0 4 6 .061 .10 6 4 3.988 .674

49 B 1. 511 8 J , 052 14.780 2.963 .276 .235 .041 .056 . 0 87 43 . 790 .674

50 A 1. l15 60, 291 1 4 . 6u 0 2.973 .282 .234 .044 .059 .102 43. 949 .67 4

5 0 8 1. 573 80 , 0 3 4 14.733 2. 956 . 274 .235 .039 .052 .083 43.736 .674

5 1 A 1 128 60 , 521 14. 719 2.923 .277 .230 .044 .058 .100 43 . 919 .o72

1 c ( O 1 ^ • b t>*+ ? a 7 s c. • vcc it/1 • C oC .0^0 t UP U

n Q c; U4ji7 7rot7 7 '7?

52 A i 19 1 c u . 291 14. 842 2. 949 .264 .236 .044 . 0b 0 .103 43.963 . 674

52 B 1

.

53-r 80 . 022 14.777 2. 9c7 . 273 .238 .044 . 053 .088 43.799 . 674

53 A 819 77. 58<» 15.717 3.124 .296 . 246 .046 .061 .106 44.432 .679

53 6 1 . c56 7 ) h36 1 5 .668 3.113 . 288 .244 .044 .056 .095 44.336 .679

54 A 90 6 a j < 445 14.907 3.006 .287 .239 • 0 4 5 .060 .10 4 4 4.131 .673

54 B 1

.

181 80. 2 4 5 14.858 3. 0 Jb .278 .238 .043 . 052 .099 43.934 .674

55 A 884 80 . 742 14.805 2.874 .272 .225 .043 . j57 .098 43. 994 .671

55 B 1 157 60. 557 14. 7b2 2. 6b3 . 268 .227 .036 .046 .0 80 43.826 . 671

56 A 9o7 79. 90 1 15. 344 3. u95 .295 .245 .046 . 061 .106 44.322 .677

5 6 B 1 93 3 79. 66 8 14.737 2.971 ? 7 7 • CI t .COP .040 1 C 7

• U 5 >S • 0 8 6 '3.619 » 0 / b 57 A 85 7 7 9. 8dC 15. 482 3.044 .288 .239 .045 . 060 .105 44.337 .676

57 A Bbl 7, 920 15.462 3. u27 . 283 .239 .044 .060 .103 44.312 .676

57 B 2 173 79. 399 14. 831 2.915 .270 .229 . 043 .052 .090 43.518 . 676

57 B a, 018 79 598 14 . 8 u 0 2.909 . 2o9 .229 .039 . 052 .086 43.555 .675

5 6 A 93 6 79 < 9 9 8 1 5

•

2d 0 3.058 • 292 .2 42 • 0 * 7 .061 . 1 Q 5 '4.259 C 7 c .6/6

58 B i cl 7 79 798 15.202 3.056 .286 .242 .044 . J53 .101 44.112 . 676

59 A -» 114 7h 164 17.153 3.670 .343 .291 .054 .078 .134 44.102 .707

59 B 4 uc9 7 4 247 17

.

1p0 3. c65 .340 .292 .050 . Obb .121 44. 076 . 706

60 A 4, 132 74, 144 17.160 3. 664 . 348 .291 .054 .076 .132 44. 093 .707

6 u

jio

c £ 7 7 6 01 1 £L (. 7 U loiHf

O

3 n; 7 n O . P £ U . - C *7 ? A f. • cob n /_» a

1 u HO .1 c; • U 0 Z> • 1 u 0

7 .1 7 61 A 4 123 74 140 17 .181 3. 654 . 346 .291 .055 .076 .132 44.099 .707

bl B 4 < 571 ? 4 , 707 lb. 405 3.506 .328 .276 .047 .063 .097 43. 514 .702

62 A 118 74, 165 17.152 3.660 .348 .292 .055 .077 .134 44.100 . 707

b2 a 4 udt. 74, 236 17.158 3.661 . 343 .293 .046 .064 .116 44. 362 . 706

b o M 4 < 15 9 7 41 116 '7 i C c j. I • i. P 6

7 £. C 7 .34 3 .291 .055 T 7 Q

• 1 34 I.I. fill? 44 . U 0 1 7 n 7 . 1 U / 63 s 4 654 74, 355 lc.449 3.515 .328 .280 .049 . 065 .104 43. i+43 . 704

64 A 4, u 53 74, 242 17.150 3. 650 . 349 .292 .055 .077 .133 44.117 .707

6h B * < 482 74. 6- 8 16.536 3.531 . 329 .281 .053 . 065 .116 43.642 .703

65 A 4 . 083 74. 271 17.097 3. 648 .346 .291 .055 . 077 .133 44.086 .706

o 5 d 4 I r> 7 7 Hoi 7 4 . 3 5 2 1 7 . 09o 3.6h6 7 /. 7

• 04,3 7 Q «

1 C7l r, c r

• U P P .064 .116 4 ^ • 05 9 • f ut> 66 A 4, 125 74. 012 17.269 3.666 .349 .293 .054 .078 .134 44.148 . 708

67 A 4 , 10 6 74. 143 I7.1o0 3.689 . 348 .291 .054 .077 .133 44.119 .707

67 A 4 , 112 74. 169 17.155 3.666 .343 .291 .055 .077 .133 44. 099 .707

b7 B 4 . 0*9 7 4 256 17 .156 3.666 . 343 .289 .049 .065 .127 44. 092 .706

67 B 4 1 063 74. 236 17.169 3.667 . 344 .291 .053 . 066 .112 44.076 .706

66 « 4 u 6 5 74. 2 J 3 17.195 3.634 .347 .291 .0 54 .077 .134 44.115 . 707

68 B 4 00 a 74. 274 17.183 3.668 . 343 .292 .053 . 069 . Ill 44.104 .706

69 A 4 13<- 74, 121 17.182 3. 658 .350 .292 .055 . 077 .134 44.103 .707

69 a 4 092 74. 134 17.187 3.672 . 043 .290 .051 . 066 .115 44. 074 .706

70 A 4 1 o34 74. 214 17.191 3.655 . 349 .292 .054 .077 .134 44.139 .707

70 B 4 00 2 74. 530 17.248 3. 685 .005 . 290 .051 . 070 .121 43. 360 .702
Table 7.4.2. LNG Flow Facility Test 2 Data (continued)

Pun 1T nt1 1 Lcd- CH

4

C

2 H6

C

3 H Number grator 8 N

2 71 A <*.U35 7h.196 17. 19* 3. 669

71 3 3. 985 7*. 289 17.169 3.670

72 A 3.562 7*.*2G 17. 38"* 3.713

72 A 3.556 7*.**li 17.399 3.720

72 B 3. 52 8 7* . *80 17 .*«6 3.713

72 6 3.517 7k.t*79 17 .*07 3. 720

73 A 3 . 991 7*. 209 17.227 3.665

73 6 3.955 7... 23* 17.217 3.630

7* A 3.226 7*. 6*7 17.^93 3.712

7* B 3.187 7*. 716 17 ,*86 3. 729

75 A 2.678 7*. 726 17.712 3.7*9

75 a 3.36** 75. 315 16 . 8*9 3. 61u

7b A 3. 25^ 7^. 596 17.*61 3. 7*2

7b B 3. 22C 7*. 673 17 .*o2 3. 733

77 A 3 . 980 ?

' H . 3 1 0 17.178 3.627

77 B *. 661 7"*. 669 lb . 365 3.*93

Composition, mol %

H

- ng

Us lno r C 4

H 10nC

4

H 1Q

iC

5 H 12 nC

5 H 12 V

vaiue MJ/m 3 Gravity

• 3*9 • 292 .055 .077 . 13* *<. 1*9 .707

.3*0 . 292 .0*9 . 0o6 .121 **. 121 .706

.356 .2 97 .056 .076 .135 **.*23 .707

. 3*8 .296 .055 . 076 .136 **. *25 . 707

. 3*7 .296 .053 .06 8 .109 **. 378 .706

. 3*9 .297 .050 . 069 .113 ** . 392 . 706

• 3*9 .292 . D55 .078 .135 **. 175 .707

. 3** .292 .052 .067 .10 9 ** . 1 36 . 70S

.355 .296 .055 .079 .136 ** . 582 . 706

. 3*9 .296 .053 . 068 .117 **.553 .705

.360 .302 .056 .030 .136 **. 310 .706

.335 .285 .050 . 065 .106 **. 187 .701

.355 .296 .057 .077 .13* **. 580 .706

. 3*9 , .297 .056 . 0o9 .122 **. 55* . 705

. 3*7 . 292 .05* .077 .13* **. 139 .706

.326 .278 .0*7 . u61 . lOu *3. *6* .702
8 . ACKNOWLEDGMENTS

The authors thank the following companies for their financial and technical support: El Paso Marine Company, Columbia LNG Company, Consolidated

System LNG Company and Southern Energy Company. Messers I. W. Schmidt and

R. D. Kinley of El Paso Marine arranged for the tests aboard the LNG tanker.

Also, Mr. Kinley reviewed the final manuscript of this report.

Within the Cryogenics Division D. B. Mann, J. A. Brennan and J. Hord

provided technical advice. C. F. Sindt helped in the initial design and

construction of the laboratory apparatus. J. A. Brennan and C. H. Kneebone

put in many long hours during the NBS flow facility tests. J. D. Siegwarth

made many of the tests involving gas chromatograph performance. Finally,

special thanks goes to Mrs. S. L. Erickson who had the patience to do an excellent job preparing the manuscript.

196
NBS-1 14A (REV. 7-73)

U.S. DEPT. OF COMM.

BIBLIOGRAPHIC DATA

SHEET

1. PUBLICATION OR REPORT NO.

NBSIR 78-887

2. Gov't Accession

1NO. 3. Recipient's Accession No.

4. TITLE AND SUBTITLE

DEVELOPMENT AND EVALUATION OF AN LNG SAMPLING

MEASUREMENT SYSTEM

5. Publication Date July 19 78

6. Performing Organization Code

736

7. AUTHOR(S)

W. R. Parrish, J. M. Arvidson and J. F. LaBrecque

o. rerrorming Urgan. Report No.

9. PERFORMING ORGANIZATION NAME AND ADDRESS

NATIONAL BUREAU OF STANDARDS

DEPARTMENT OF COMMERCE

WASHINGTON, D.C. 20234

10. Project/Task/Work Una No. 7360575

11. Contract/Grant No.

12. Sponsoring Organization Name and Complete Address (Street, City, State, ZIP)

LNG Sampling Measurement Supervisory Committee

13. Type of Report & Period

Covered

14. Sponsoring Agency Code

15. SUPPLEMENTARY NOTES

16. ABSTRACT (A 200-word or less factual summary of most significant information. If document includes a significant

bibliography or literature survey, mention it here.)

This report describes the development and evaluation of procedures

and components for sampling and analyzing LNG from flowing streams.

Laboratory and field test results showed the total uncertainty in the

computed heating value of samples taken with the recommended sampling

system could be routinely within +0.3 percent; this included the +0.1

percent uncertainty in analysis by gas chromatography. Three sample

probes and two vaporizer designs were considered. Of the ten operating

variables considered, six were found to be important in sampling. Test

results were used to establish recommended design and operating criteria.

17. KEY WORDS (six to twelve entries; alphabetical order; capitalize only the first letter of the first key word unless a proper name; separated by semicolons

Custody transfer; density; gas analysis; gas chromatography; heating

value; hydrocargon; liquefied natural gas; phase. equilibrium; pipelines;

sampling

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UNCL ASSIFIED

199

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Washington. D.C. 20402. SD Cat. No. C13

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