### RCN 213-210-06-08



### ffigh S02 

### Removal Efficiency 

### Testing
DE-AC22-92PC91338 

## I 

## M Topical Report Results of Sodium Formate Additive Tests at New York State Electric & 

### Gas Corporation's Kintigh Station

Prepared for: Janice Murphy U.S. Department of Energy Pittsburgh Energy Technology Center P.O. Box 10940 Pittsburgh, PA 15236

Prepared by: Radian Corporation

P.O. Box 201088 Austin, TX 78720-1088

14 February 1997 

# T

DISTR!BUT!ON OF THIS DOCUMENT IS UNLIMITEDU- ----------------------------------

## DISCLAIMER 

## Portions of tbis 

## document may be Dlepole ill electronic jmage 

## products.

. Images are produced from the best available original 

## document.

### TABLE OF CONTENTS
Page 

### SUMMARY

............. , ..................................... S;..1 1.0 INTRODUCTION

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

### 1-1 1.1 Background

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

### 1-1 1.2 Project Description

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

### 1-2 1. 3 Report Organization

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

### 1-3 2.0 TEST CONDITIONS AND RESULTS

............................ 

### 2-1 2.1 FGD System Description

................................. 

### 2-1 2.2 Test Approach

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

### 2-4 2.2.1 Baseline Tests

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

### 2-4 2.2.2 Parametric Tests

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

### 2-5 2.2.3 Sodium Formate Consumption Test

..................... 

### 2-6 2.3 Test Measurements

..................................... 

### 2-7 2.3.1 Flue Gas 

### Sampling

................................ 

### 2-7 2.3.2 Slurry Sampling

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

### 2-8 2.3 .3 Chemical Analyses of Slurry and Filtrate Samples

. . . . . . . . . . . . 

### 2-9 2.3.4 Other Process Data

..................... ,, . . . . . . . . . 

### 2-10 2.4 S02 

### Removal Efficiency Test Conditions and Results

. . . . . . . . . . . . . 

### 2-10 2.4.1 Baseline Test S02 

### Removal Efficiency

. . . . . . . . . . . . . . . . . . 

### 2-10 2.4.2 Baseline Test CEM Traverse Data

. . . . . . . . . . . . . . . . . . . . . 

### 2-13 2.4.3 Sodium Formate Parametric Test S02 

### Removal Efficiency

. . . . . 

### 2-13 2.4.4 S02 

### Removal Performance Correlations

. . . . . . . . . . . . . . . . . 

### 2-17 2.5 Results of Slurry Sample Chemical Analyses

. . . . . . . . . . . . . . . . . . . 

### 2-19 2.5.1 Solid-Phase Analyses

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

### 2-19 2.5.2 Liquid-Phase Analyses

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

### 2-25 2.6 Sodium Formate Consumption Test Conditions and Results

. . . . . . . . . 

### 2-26 2.6.1 Consumption Rate Calculation

. . . . . . . . . . . . . . . . . . . . . . . 

### 2-26 2.6.2 Results

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

### 2-28 2.7 Effect of Sodium Formate Additive on Solids Dewatering Properties

. . . 

### 2-32 2.7.1 Settling Test Results

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

### 2-32 2. 7.2 Filter Leaf Tests

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

### 2-36 2.7.3 Scanning Electron Microscope (SEM) Photographs

. . . . . . . . . . 

### 2-36 2.8 Other Process Data

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

### 2-42 2.8.1 Control Room Data.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

### 2-42 2.8.2 Recycle Pump 

### Slurry Flow Rate Measurements

. . . . . . . . . . . . 

### 2-42
i

### TABLE OF CONTENTS (Continued)
Page 2.8.3 S02 

### Removal Data for the Consumption Test.

. . . . . . . . . . . . . . . . . . . . . . . 2-42 3.0 FGDPRISM MODELING RESULTS

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1 3.1 FGDPRISM Calibration Results

............................ 3-1 3.2 Predictive Simulations

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2 4.0 ECONOMIC EVALUATION

.................................. 4-1 

# " 4.1 Upgrade Options and Cost Basis

. . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1 4.2 Results

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4 4.2.1 Effect of Sodium Formate Additive Price on Results

. . . . . . . . . . 4-8 4.3 Recommended Upgrade Option

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-8

APPENDIX A:

APPENDIXB:

APPENDIXC: APPENDIXD: APPENDIXE: Detailed S02 

### Removal Data and Chemical Analyses Results for Baseline and Parametric Tests

.................... A-1 Detailed Formate Material Balance Data and Chemical Analyses Results for the Sodium Formate Consumption Test

. . . . . . B-1 Other Process Data

. . . . . . . . . . . . . . . . . . . . . . . . . . . C-1 FGDPRISM Calibration

. . . . . . . . . . . . . . . . . . . . . . . . D-1 Detailed Economic Calculations

. . . . . . . . . . . . . . . . . . . E-1

ii

### 2-1 LIST OF FIGURES

Flow Diagram ofNew York State Electric and Gas Kintigh Station's FGDSystem Page

2-2 2-2 Results ofCEM Traverses at Module E outlet (ppm S02 

### dry)

................. 2-14 2-3 Adjusted NTU vs. Formate Concentration for Tests at pH= 5.6

............... 2-20 2-4 Adjusted NTU vs. pH for Tests 

### with 1000 ppm Formate

..................... 2-21 2-5 Baseline Test Limestone Utilization vs. Slurry pH

......................... 2-23 2-6 Parametric Tests Limestone Utilization vs. Slurry pH

....................... 2-24 2-7 Comparison of Baseline and Long-Term Tests Limestone Utilization

.......... 2-33 2-8a. Solids from Baseline Test 1 (500x)

..................................... 2-38 2-8b. Solids from Baseline Test 1 (1 OOOx)

.................................... 2-38 2-9a. Solids from Parametric Test 1 (500x)

.................................... 2-39 2-9a. Solids from Parametric Test 1 (lOOOx)

................................... 2-39 2-10a. Solids from Parametric Test 2 (500x)

.................................... 2-40 2-10b. Solids from Parametric Test 2 (lOOOx)

................................... 2-40 2-lla. Solids from Parametric Test 9 (500x)

.................................... 2-41 2-llb. Solids from parametric Test 9 (1000x)

................................... 2-41 3-1 Kintigh FGDPRISM Calibration: Predicted vs. Observed Removal

............. 3-3



### iii

### LIST OF TABLES
Page 

### 2-1 Average Baseline Test Conditions and Results

............................ 2-11 2-2 Average Sodium Formate Parametric Test Conditions and Results

............. 2-15 2-3 Summary of Sodium Formate Consumption Test Results 2-29 2-4 Results of Settling Tests

.............................................. 2-35 2-5 Results of Filter Leaf Tests

............................................ 2-37 2-6 Results ofRecycle Pump Flow Measurements

............................. 2-43 2-7 S0 2 

### Removal Efficiency During Consumption Test

........................ 2-44 4-1 Economic Basis for Kintigh S02 

### Removal Upgrade Options

................... 4-2 4-2 Economic Comparison of S0 2 

### Removal Upgrade Options

.................... 4-5

DISCLAIMER
This report was prepared as an account of work sponsored by an agency of the United**Sta~** Government. Neither the United States Gl)vernment nor any agency**ther~f, .n~r**  any of thet_r employees, makes any warranty, express or implied, or**ass~mes** any_ legal hablltty or respon:; bility for the accuracy, completeness, or usefulness of**~y ~nform~uon,**  apparatus: product, • process disclosed, or represents that its use would not mfnnge**~nvately** owned nghts. Refer ence herein to any specific commercial product, process, or service by _trade name, trademark, manufacturer. or otherwise does not necessarily constitute or imply 1ts endorsement,**r~m·** mendation, or favoring by the United States Government o_r any agency thereof. The vtews and opinions of authors expressed herein do not necessanly state or reflect those of the United States Government or any agency thereof.



### iv

### SUMMARY

Tests were conducted at New York State Gas & 

### Electric's (NYSEG's) Kintigh Station to evaluate options for achieving high sulfur dioxide**(S~)** 

### removal efficiency in the wet limestone flue gas desulfurization (FGD) system. This test program was one of six conducted by the U.S. Department of Energy to evaluate low-capital-cost upgrades to existing FGD systems as a means for utilities to comply with the requirements of the 1990 Clean Air 

### Act Amendments. The upgrade option tested at Kintigh was sodium formate additive.

Results from the tests were used to 

### calibrate the Electric Power Research Institute's (EPRI) FGD PRocess Integration and .Simulation Model (FGDPRISM) to the Kintigh scrubber configuration. FGDPRISM was then used to predict system performance for evaluating conditions other than those tested. An 

### economic evaluation was then done to determine the cost effectiveness of various high-efficiency upgrade options. These costs can be compared with the estimated market value of S0 2 

### allowances or the expected costs of allowances generated by other means, such as fuel switching or new scrubbers, to arrive at the most cost-effective strategy for Clean Air 

### Act compliance. Results from the test program at Kintigh are summarized below.
SQ 2 

### Removal Performance. Baseline tests on one module ofNYSEG's Kintigh Station wet limestone FGD system showed that the**S~** 

### removal efficiency at normal full-load operating conditions (pH 5.6, flue gas velocity 

## = 9 ftls, four recycle pumps operating) was about 86%. Tests with sodium formate additive showed that the 

## SOz removal efficiency could be increased to as high as 99.4% with a formate ion concentration of 3800 mg/L in the recycle slurry. The sodium formate additive had no significant effect on process chemistry or on the dewatering properties of the calcium sulfite byproduct solids.

Sodium Formate Additive Consumption. 

### In a long-term sodium formate consumption test with sodium formate added to the entire FGD system, an average additive
S-1feed rate of 168 lb/hr (as sodium formate) was required to maintain an average concentration of 1080 mg/L formate ion 

### in the recycle slurry at full-load operation. At this formate concentration, S02 removal efficiency averaged about 97%

. The total sodium formate additive consumption rate was 16.6lb/ton of S0 2 removed. Of the total formate consumed, 12% was lost with the filter cake liquid, about 32% was lost by precipitation with the filter cake solids, about 6% was lost by vaporization into the flue gas, and the remaining 50% was attributed (by difference) to oxidative degradation

. 

### .80 2 Removal Upgrade Economics. The economics of sodium formate addition
were evaluated based on a capital cost of $300,000 for a 100 lb/hr additive storage and delivery system, and using operating cost data provided by NYSEG. Using sodium formate additive at 1000 mg/L in the recycle slurry, more 

### than 10,000 additional tons per year of S02 could be removed by the Kintigh FGD system at an average additional cost of only $76/ton. Depending on the assumed value of S0 2 allowances ($150 to $250/ton), the estimated net annual value of additional S02 removal at Kintigh ranged from $0.8 to $1.8 million.

Further analysis, based on performance predictions using FGDPRISM, suggested that sodium formate additive could be used to maintain the current 85% average S02 removal (with partial bypass) while operating fewer recycle pumps, resulting in a net annual savings of about $100,000. FGDPRISM also predicted that a significant performance improvement could be obtained by operating with a rmer limestone grind. This might be done by operating the reagent preparation equipment at a lower throughput for two shifts per day instead of one shift per day. Some modifications to the ball mill classifier would also be required.

S-2

### 1.0 INTRODUCTION

This report describes the results of tests conducted at New York State Gas & Electric's (NYSEG's) Kintigh Station to evaluate options for upgrading the flue gas desulfurization (FGD) system's S02 removal efficiency using sodium formate additive. The objective of these tests was to obtain performance data needed to evaluate the cost effectiveness of upgrading an existing FGD system as part of a strategy for meeting requirements of the 1990 Clean Air Act Amendments.



### 1.1 Background

Provisions of the Clean Air Act Amendments of 1990 call for a ten-million ton per year reduction in U.S. S0 2 emissions (from a 1980 baseline) in two phases. Phase I calls for
a five-million ton per year reduction by 1995, and the remainder of the reductions are to be completed by the year 2000 for Phase IT. Affected utilities have a number of options for achieving these reductions, such as switching to lower sulfur-content coals, installing new FGD systems, and improving the S0 2 removal performance of existing FGD systems. Some utilities may employ a combination of these and other options as part of an overall compliance strategy.

The Flue Gas Cleanup (FGC) Program at the U.S. Department of Energy Pittsburgh Energy Technology Center (DOE PETC) helps to maintain and foster the widespread
use of coal by developing technologies that will mitigate the environmental impacts of coal utilization. The program focuses on post-combustion technologies for the control of S0 2 , oxides of nitrogen, particulate matter, and air toxics generated from coal combustion. A portion of the FGC Program, including this project, involves enhancing the S0 2 removal efficiencies of existing wet FGD systems. The results from this project will allow utilities to better consider enhanced performance of existing FGD systems as an option for achieving compliance with Phase I and/or Phase IT of the Clean Air Act Amendments.

1-1In this project, Radian Corporation is conducting tests at six full-scale FGD systems to evaluate options for achieving high S0 2 removal efficiencies (95 to 98% removal). Each system is being characterized under baseline operation and then with additives or with other modifications to enhance S02 removal performance.

The systems being evaluated are at Tampa Electric Company's Big Bend Station, Hoosier Energy's Merom Station, Southwestern Electric Power Company's Pirkey Station, PSI Energy's Gibson Station, Duquesne Light Company's Elrama Station, and the New York State Electric and Gas Corporation's (NYSEG) Kintigh Station. A wide variety of FGD system vendors and designs are represented in the program. Most of these systems were designed to achieve 85 to 90% 

## so2 removal.

This Topical Report covers only results from the sixth site, at NYSEG's Kintigh Station. Separate Topical Reports have been issued for each of the other sites.


### 1.2 Project Description

Three types of performance tests were completed at Kintigh. First, "baseline" tests were done to obtain performance data without the sodium formate additive. Then, "parametric" tests were done to evaluate performance using the additive at various concentrations. The baseline and parametric tests were done using only one of the four operating absorber modules. Following the parametric tests, a steady-state sodium formate consumption test was done by adding sodium formate to the entire FGD system.

Under a separate project funded by the Electric Power Research Institute, their FGD PRocess Integration and**~imulation** Model (FGDPRISM) was calibrated to the Kintigh FGD system configuration. The calibrated FGDPRISM model was then used to predict system performance for evaluating conditions other than those tested.

1-2Actual performance results, along with the steady-state sodium formate consumption 

### data and pertinent cost information provided by NYSEG, were used as the basis for
an economic evaluation. In this evaluation, the net cost of additional tons of S0 2 removal was estimated for different operating conditions and formate concentrations. These costs can be compared with the estimated market value of S02 allowances or the expected costs of allowances generated by other means, such as fuel switching or new scrubbers, to arrive at the most costeffective strategy for Clean Air Act compliance.


### 1.3 Report Organization

The performance tests are described and results are presented in Section 2 of this topical report. The FGDPRISM calibration and performance predictions are discussed in Section 3, and the economic evaluation is addressed in Section 4. Detailed results and calculations are included as Appendices A through E.



### 1-3

### 2.0 TEST CONDITIONS AND RESULTS

This section describes the full-scale FGD system tests conducted at the NYSEG Kintigh Station and provides an overview of the results. The tests evaluated methods for achieving high S0 2 removal efficiency with the Kintigh FGD system and followed a methodology used for the other sites included in this DOE-PETC program.
This section presents and discusses results from each of these three phases of testing at Kintigh. 

### In Section 2.1, the FGD system is briefly described. The test approach and measurement methods are outlined in Sections 2.2 and2.3. Results of the short-term baseline and sodium formate parametric tests are presented in Sections 2.4 and 2.5. Results of the systemwide sodium formate consumption test are described in Section 2.6. Following this, the effects of sodium formate additive on FGD byproduct solids is discussed in Section 2.7, and other process measurements are summarized in Section 2.8.
I 

### 2.1 FGD System Description

The NYSEG Kintigh Station is located in Niagara County near Barker, New York. Figure 2-1 is a simplified flow diagram for the Kintigh FGD system showing the arrangement of
a single absorber module. Flue gas exits the boiler and passes through electrostatic precipitators (ESPs) for particulate control. From the ESPs, flue gas goes through three parallel ID fans and then to the FGD system. At full load, four modules are required to treat flue gas from 700 MW of generating capacity. There are two additional spare modules.

The absorber modules are Peabody open spray towers. In this configuration, flue gas enters the side of the vessel near the bottom and flows upward. A recirculating slurry is sprayed downward, countercurrent to the gas flow, through up to five levels of spray headers. Each spray header level on the absorber has its own recycle pump. The combined liquid-to-gas ratio (UG) is about 116 gal/1 

### 000 acf, with all five headers in service on each of four operating modules at the full-load flue gas flow rate. However, only four headers per absorber module are 2-1tvItvBypassIIFlueGasFromESPsToHydroclonesFresh...,.........,.......,...1..'WaterPump4PumplPumpSPump2PumpProcessHydroclones1,.1FromPrimaryReactionTankToVacuumFilters.------------,_j1rLimestoneFreshWater+InletWallWashHydrocloneFeedPumpRecyclePump+..ISecondaryReactionTankt=JalWasteSlurrySumpSupernateTankFigure2-1.FlowDiagramofNewYorkStateElectricandGasKintighStation'sFGDSystemtypically required to achieve S02 emissions compliance 

### (0.6 lb SO/million Btu), which is equivalent to about 85% overall S02**re~oval.**
Mter leaving the spray section, the flue gas flows past a sieve tray to a verticalgas-flow mist eliminator. From the mist eliminator, flue gas exits the top of the absorber module. The combined absorber exit gases then flow to the stack through a common outlet duct. The FGD system is equipped with an absorber bypass duct. However, nearly all of the flue gas from the boiler is typically treated in the absorbers, and the stack operates in a "wet" mode. A small amount of flue gas is bypassed to prevent excess condensation in the absorber outlet plenum.

The reagent used in the FGD system is a slurry of ground limestone. The limestone is ground in ball mills, and the prepared slurry is stored in two slurry feed tanks, from which it is added to the absorbers to maintain the recirculating slurry pH set point. Elemental sulfur emulsion is also added to the limestone slurry feed tanks to produce thiosulfate ion in the absorber reaction tanks, to serve as an oxidation inhibitor.

The recirculating slurry drains from the absorber into a secondary reaction tank external to the tower. In the secondary reaction tank, fresh limestone slurry is added to control the recirculating slurry pH. Slurry from the secondary reaction tank then flows by gravity to the primary reaction tank, which is integral to the bottom of the absorber. The slurry recirculation pumps draw suction from the primary reaction tanks.
Slurry from the primary reaction tank is also recirculated to hydroclones. A portion of the low-solids-content overflow from the hydroclones is used to wash the underside of the sieve tray below the mist eliminators. The remainder is routed to a baffled section in the primary reaction tank in the base of the absorber, from which it overflows to a waste sump along with a portion of the slurry from the primary reaction tank. The high-solids-content underflow from the hydroclones falls into the external, secondary reaction tank.

2-3Waste slurry overflows from the primary reaction tank on each absorber to a waste slurry sump, where it is combined with a small bleed stream from the secondary reaction tanks and some recycled thickener overflow. This mixed waste stream is fed to two thickeners. Liquor overflow from the thickeners flows to a supernate tank, and the underflow is pumped to slurry storage tanks and then to vacuum filters. The filtrate from the vacuum filters is returned to the thickeners. Supernate is returned to the absorbers by being used in the limestone grinding circuit and by makeup to the secondary reaction tanks. The slurry density in the modules is controlled by adjusting the rate of supernate return. The primary makeup of fresh water to the FGD system is via the mist eliminator wash and pump seals. Additional makeup is added to the supernate tank to maintain system liquid level.

The dewatered FGD sludge is blended with lime and fly ash from the ESPs for stabilization before being landfilled on the site. The solids content of the dewatered FGD sludge is approximately 7 5 weight percent.


### 2.2 Test Approach

The baseline and parametric tests were conducted on a single module (Module E) of the FGD system. Module performance was measured by sampling the flue gas at the inlet and outlet. Slurry samples from the reaction tank were obtained concurrently with the flue gas samples. Sampling locations are indicated on Figure 2-1.


### 2.2.1 Baseline Tests

For the baseline tests, independent variables included primary reaction tank pH, liquid-to-gas ratio (UG), which was varied by changing the number of recycle pumps in service, and flue gas velocity in the test module. The four operating modules receive flue gas from a common plenum so that the flue gas flow to the test module could not be independently controlled. During the baseline tests, a constant high load was maintained and the flue gas flow to the test module varied only slightly depending on the number of operating pumps. One 2-4baseline test was conducted with five operating modules to investigate the effect of changing flue gas velocity.

The baseline tests began with a two-day test at NYSEG's normal operating conditions. This test duration was sufficient to approach steady-state operating conditions with respect to solids properties in the test module. The performance measurements during the twoday test included S02 removal, limestone utilization, sulfite oxidation, solids dewatering properties, and relative saturations for precipitating and dissolving species.

The two-day test was followed by a series of half-day tests during which only S0 2 removal and limestone utilization were expected to represent steady-state conditions. During the half-day tests, the slurry pH set point and number of operating spray pumps were varied. During the final baseline test, the flue gas velocity in the test module was deliberately lowered by operatiug a spare module.


### 2.2.2 Parametric 

### Tests

For the parametric tests, independent variables included reaction tank pH, number of recycle pumps in service, and sodium formate additive concentration. Flue gas velocity was not intentionally varied during the parametric tests, but the unit load varied substantially during this test series. The flow to the test module was controlled to the extent possible by varying the number of operating modules and by manually adjusting the module inlet dampers, but the flue gas velocity in the test module actually varied from 6.0 to 9.3 ft/s.

Three two-day tests (Tests 1, 2, and 9) were done at three increasing sodium formate levels so that the effect of sodium formate on steady-state performance could be measured. For these two-day tests, performance measurements included S02 removal, limestone utilization, sulfite oxidation, solids dewatering properties, and relative saturations of limited solubility species such as gypsum. A series of half-day tests (Tests 3 through 8) were completed at the mid-level formate concentration to investigate the effects of slurry pH and number of 2-5operating pumps on 802 removal. A final half-day test was done at a high sodium formate concentration to determine the maximum 802 removal capability ofthe test module.

For the parametric tests, sodium formate was fed continuously to the test module reaction 

### tank to maintain the desired concentration during and between tests. The sodium formate concentration was measured prior to each test and adjusted if necessary by pumping additional sodium formate from the tanker into the reaction tank.


### 2.2.3 Sodium Formate Consumption Test

The parametric tests were followed by a steady-state sodium formate consumption test. The objective ofthe consumption test was to measure the amount of sodium formate required to maintain high S02 removal efficiency with the entire FGD system. Sodium formate
was added to the reaction 

### tanks of each of the four operating modules and to the A and B thickeners to bring the entire system formate concentration to approximately 1000 mg/L (as formate ion). Sodium formate was then added continuously to the waste slurry sump to maintain this system-wide concentration until the conclusion ofthe consumption test.

The sodium formate consumption rate was determined by liquid-phase material balance. The amount of formate added was carefully measured by gauging the tanker. The most straightforward and predictable loss of sodium formate from the system is with the liquor that remained adhered to the byproduct solids ("solution loss"). This loss rate was determined by measuring the filter cake moisture content and the formate concentration in that moisture, and by quantifying the filter cake production rate. The difference between the amount added and the amount lost with the filter cake, plus an "accumulation" term which accounts for changes in sodium formate concentrations in the system over the test duration, yielded the total amount of formate consumed by other mechanisms, including vaporization, precipitation, and oxidization. Formic acid vaporization was measured independently by flue gas analysis and formate precipitation was measured by analysis ofthe filter cake solids. Thus, the formate oxidation rate could be determined by difference. 

### 2-6For at least one hour during each day of the formate consumption test, the bypass damper was closed so that S02 removal efficiency could be determined using the inlet and stack continuous emissions monitors.


### 2.3 Test Measurements
2.3.1 Flue Gas Sampling

The primary performance measurements obtained at the site included inlet and outlet flue gas S0 2 concentrations and flue gas velocity for the test module. Inlet concentrations
were determined using NYSEG's existing on-line certified S0 2 analyzer. The relative accuracy of this analyzer was verified by pre-test EPA Method 6 samples at the module inlet. Module outlet S0 2 concentrations were measured using a modified EPA Method 6 with a composite flue gas sample obtained by a 24-point isokinetic traverse of the module outlet duct. The total test module gas flow rate was measured during the same traverse. During some of the baseline tests, the outlet flue gas S02 concentrations were also measured at the individual traverse points using
a portable flue gas analyzer.
During a typical half-day test, the performance of the test module was measured by completing duplicate flue gas 

## so2 and velocity traverses at the module outlet, while inlet 

## so2 concentrations were recorded at five-minute intervals and averaged over the duration of each outlet traverse. For tests with longer durations, the half-day gas sampling schedule was repeated,
so that up to eight individual gas measurements were obtained during a two-day test.

Flue gas S0 2 concentrations were determined on site from the Method 6 samples using the barium perchlorate titration procedure. These on-site data were used to verify that test results were consistent and reasonable and to make testing decisions. The Method 6 impinger solutions were also analyzed off site by ion chromatography as a quality control check and to improve the accuracy of results for tests at very high S0 2 removal efficiency.

2-7During selected parametric tests, the concentration of formic acid in the flue gas was also determined by drawing a measured amount of flue gas through an impinger train containing dilute sodium hydroxide. The amount of formic acid captured in the impinger solution was then determined by ion chromatography.


### 2.3.2 Slurry Sampling
During the baseline and parametric tests, slurry samples were obtained from the test module by sampling at the hydroclone feed location, which is the sampling point used by NYSEG for routine process monitoring. The slurry samples were timed to coincide with the Method 6 outlet flue gas traverses.

At the beginning of each set of duplicate outlet S02 traverses, the slurry pH was measured using a calibrated portable pH meter, and a slurry sample was obtained. In the time between each set of duplicate traverses, the pH was again measured, another slurry sample was obtained, and a set of diluted, stabilized filtered liquor samples was also obtained. At the conclusion of each set of duplicate flue gas S02 traverses, the pH was again measured and a final slurry sample was obtained. During the second day of each two-day test, slurry samples were also obtained for dewatering tests. Settling rate tests were conducted on site with slurry samples at process temperature. Samples were also collected at the same time for off-site filter leaf tests. During the formate consumption test, samples were obtained from the major system vessels to monitor the formate concentration. Formate was measured on site by buffer capacity titration. Samples were also obtained for off-site analysis by ion chromatography. Sufficient data were obtained to determine the formate consumption rate by material balance calculations. Slurry and filtered liquor samples were also obtained from the operating modules during the consumption test to document any effects of sodium formate additive on the process chemistry during the week of operation in this mode. 2-8

### 2.3.3 Chemical Analyses of Slurry and Filtrate Samples

The number of solid and liquid chemical analyses made depended on the importance of the results to the performance evaluation and on the expected time constants for changes in concentrations of the various species.

All of the slurry samples were analyzed for weight percent solids content and solid-phase carbonate. These results were used to calculate limestone utilization, which is an important performance parameter. Limestone utilization can change relatively quickly with operating pH. Complete solid-phase analyses including calcium, magnesium, sulfite, sulfate, and carbonate were done only for the slurry samples that were collected at the midpoint of each set of duplicate Method 6 traverses. The complete solid-phase analyses were used to calculate the sulfite oxidation fraction. This is also an important performance parameter, but the time constant for changes in slurry sulfite/sulfate content in the reaction tank is much longer than that for carbonate content. Therefore, it was not necessary to measure oxidation fraction as frequently as limestone utilization. The oxidation fraction is also not as sensitive to minor changes in operating pH as the limestone utilization. Slurry solids samples from the two-day baseline test and from each of the two-day parametric tests were examined and photographed using scanning electron microscopy.

All of the filtered slurry liquid samples were analyzed for liquid-phase calcium, sulfite, sulfate, and carbonate. These results were used to estimate relative saturations for the precipitating and dissolving species. Relative saturations are important process chemistry indicators that can change relatively quickly with changes in operating conditions, especially pH. Only one liquid sample per day was analyzed for soluble species such as magnesium, sodium, chloride, and thiosulfate. The time constant for changes in soluble species concentrations is

2-9usually on the order of weeks. Therefore, these concentrations were not expected to vary significantly during a test day.

Filtered slurry liquid samples from the two-day baseline test and from each of the two-day parametric tests were analyzed for 32 elements using inductively-coupled plasma emissions spectroscopy (ICPES).


### 2.3.4 Other Process Data

Other process data including boiler load, ID fan motor current, recycle pump discharge pressures and motor current, FGD system temperatures and pressures, and stack CEM data were either logged automatically by the plant data acquisition system or recorded from local indicators as required. Flow rates of individual slurry recycle pumps on the test module were also measured using a portable ultrasonic flow meter.


### 2.4 80 2 

### Removal Efficiency Test Conditions and Results
2.4.1 Baseline Test 802 

### Removal Efficiency

Table 2-1 summarizes the average test conditions and S0 2 removal efficiency results for the baseline tests. More detailed test data for the individual Method 6 traverses are included in Appendix A, Table A-1. In both tables, the "slurry pH" is that measured with a calibrated portable meter. In most cases (except Test 6), the portable meter agreed closely with the control room indicator. The "flue gas velocity" was calculated from the outlet duct pitot traverse, adjusted to the scrubber cross sectional area. The number of operating recycle pumps is shown for each test. Several slurry flow measurements were made for each recycle pump during the baseline test period. The 

### "UG" for each test was calculated using the average recycle pump flow rates and the average measured flue gas volume. The "inlet S02 " for each test is the average of inlet CEM readings recorded every five minutes during the outlet flue gas traverses.



### 2-10

### Table 2-1 Average Baseline Test Conditions and Results

1 

### 5.63 9.0 4 86 1549 86.2 2 5.57 8.8 5 110 1526 92 3 5.59 9.8 

### 3 61 1530 78.5 4 5.02 9.4 

### 3 63 1804 68.5 

### 5 5.18 8.7 5 110 1729 84.7 5A 4.94 9.4 4 82 1697 74

6 5.65* 9.3 

### 3 63 1692 88.3 7 5.82 8.5 5 113 1708 96.1 

## * This 

### pH reading is questionable.

2-11The baseline test series began with a two-day test at normal operating conditions (four modules on line, pH set point at 5.6, and four spray pumps operating per module). For this test at normal operating conditions, the S0 2 removal efficiency averaged about 86%.

For Tests 2 and 3, the pH set point remained at 5.6, and the number of operating pumps was varied (five pumps for Test 2 and three pumps for Test 3). The flue gas velocity changed slightly when the number of pumps was changed. Operation with five pumps increased

· S02 removal to an average of 92%, and operation with three pumps decreased removal to about

79%.

For Tests 4, 5, and SA, the pH set point was lowered to 5.2, and the number of operating pumps was varied. At this low pH set point, the S02 removal efficiency averages ranged from about 68% with three pumps operating to 85% with five pumps operating.

The pH set point was increased to 5.8 for Tests 6 and 7. This was the highest pH that could be maintained by the limestone delivery system. Some difficulty in measuring the pH
was encountered during Test 6. The portable meter was reading about 0.2 units lower than the on-line meter, even though they had agreed closely in all of the previous tests. At the high pH set point, the S0 2 removal efficiency ranged from 88% with three pumps operating to 96% with five pumps operating.

The final test, Test 8, was completed at the normal pH set point of 5.6, with five modules on line and five pumps operating to lower the gas velocity in the test module. This decreased the flue gas velocity from the normal9 ft/s to only 6.2 ftls. Under these conditions, the S0 2 removal efficiency increased to 96.5 % compared with 92% in Test 2 with five pumps operating at the normal flue gas velocity.

2-12

### 2.4.2 Baseline Test CEM Traverse Data
Figure 2-2 shows the results of the outlet duct traverses done with the portable S0 2 analyzer. The numbers inside the squares represent the measured S0 2 concentrations at the indicated positions in the duct. In this representation, the direction of flue gas flow is towards the reader. The numbers to the right of and below the squares are the average concentrations for the respective rows and columns.

Three tests were done to examine the distribution of S02 across the outlet duct. The first two were done at approximately the same gas velocity in the scrubber ( 4 Modules on line) but with different numbers of recycle pumps operating (3 and 5). The third test was done with lower gas velocity obtained by bringing a fifth module on line. The results show that there is some variation in S0 2 concentration across the outlet duct and presumably across the module. A comparison of the first two tests shows that the number of operating pumps did not have a strong effect on the S0 2 distribution across the duct. The lowest readings remained in the same relative position. The highest readings shifted from the top of the duct in the three-pump test to the bottom of the duct in the five-pump test, but these differences were not large.

The change in gas velocity had a more noticeable effect on S02 distribution across the duct. With the lower velocity, the lowest readings shifted to the top of the duct, and the average across the top of the duct was much lower than the average across the bottom of the duct. The averages down the right-hand side of the duct were also much lower than those down the left-hand side. Apparently, at low velocity, the inlet flue gas does not penetrate as well to the
rear of the absorber module (across from the inlet).


### 2.4.3 Sodium Formate Parametric Test 802 

### Removal Efficiency

Table 2-2 summarizes the average test conditions and S0 2 removal efficiency results for the parametric tests with sodium formate additive. The format of this table is the same as Table 2-1, except that the measured concentrations of sodium formate (as formate ion) in the 2-13TopofDuct 

### 275 I 

### 265 I 

### 205 I 

### 235 245 r- - 

### - - - 

### - -



### 272 I 

### 230 I 

### 159 I 

### 215 219 r- - -1
- - 1-
- """'! Test3 

### 255 I 

### 160 I 

### 98 I 

### 160 168 r- - - 

## - - - - 

### - 4 Modules, 3 Pumps, 

### 220 I 

### 136 I 

### 43 I 

### 170 142 andpH5.6 r- - -I 1- 

### - -I 

### 210 I 

### 194 I 

### 170 I 

### 185 190 r- - 

## - - - -



### 217 I 

### 226 I 

### 220 I 

### 216 220 240 202 149 197
TopofDuct 

### 312 ; 275 ; 170 ; 225 246



### - 

## - - - 

### - - 

### - 298 I 

### 215 I 

### 120 I 

### 215 212



### - -1- - 1- 

### - """'! TestS 

### 335 I 

### 160 I 

### 120 I 

### 218 208 4 Modules, 5 Pumps, - 

## - - - 

### - - - andpH5.2 

### 390 I 

### 165 I 

### 60 I 

### 296 228

- -1-
- 1-
- -I 

### 325 I 

### 255 I 

### 315 I 

### 300 299

- - 

### - 365 I 

### 325 I 

### 365 I 

### 360 354 338 232 192 269
Gas TopofDuct Inlet
I I I 

### 34 13 I 

### 0 I 

### 8 14
r- - 

## - - - 

## - 41 I 11 I 

### 0 9 15 r- - -I 

### - - 1- 

### - """'! Test7A 

### 61 17 0 9 22 5 Modules, 5 Pumps, I I I r- - 

### - 

## - - - - - and pH5.8 

### 71 I 

### 50 I 8 I 

### 22 38 r- - -1-
- 1-
- -I 

### 50 I 

### 60 I 

### 40 I 

### 29 45 r- - 

### - 

## - - 

### - - - 54 I 

### 53 I 

### 51 I 

### 35 48 ' 52 

### 34 17 19



### Figure 2-2. Results of CEM Traverses at Module E Outlet (ppm S0 2 

### dry)

2-14

### Table2-2 Average Sodium Formate Parametric Test Conditions and Results

2-15test module reaction tank are also shown. More detailed test data for the individual Method 6 traverses are included in Appendix A, Table A-2.

The parametric test series began with a two-day test at normal operating conditions (four modules on line, pH set point at 5.6, and four spray pumps operating per module) but with nominally 500 mg/L formate additive (750 mg/L as sodium formate) in the test module. For this test, the 

### S0 2 removal efficiency averaged about 97%.

Test 2, was also a two-day test. For this test, the pH set point and number of operating pumps remained at 5.6, and four pumps remained in operation. The formate additive concentration was increased to a nominal level of 1000 mg/L (1500 mg/L as sodium formate). Operation at Test 2 conditions with 

### 1000 mg/L formate increased 

### S0 2 removal to an average of 98%.

Tests 3 and 4 were conducted at the same nominal formate concentration ( 1000 mg/L) and operating pH (5.6), but the number of operating pumps varied (five pumps for Test 3 and three pumps for Test 4). In Test 3, with five pumps operating, 

### S0 2 removal efficiency increased to 99%. In Test 4, with three pumps operating, 

### S02 removal decreased to 96.6%.

The pH set point was adjusted to 5.8 for Tests 5 (five pumps) and 6 (three pumps) at 1000 mg/L formate. At the higher pH set point, the 

### S02 removal efficiency ranged from 97.4% with three pumps operating to 99.3% with five operating.

The pH set point was lowered to 5.2 for Tests 7 (three pumps) and 8 (five pumps) with the formate additive concentration remaining at the nominal 1000 mg/L level. At this lower pH set point, the 

### S02 removal efficiency was 92.3% with three pumps and 96.5% with five pumps operating. Following Tests 7 and 8, the formate concentration in the test module reaction tank was increased to approximately 1500 mg/L for Test 9. The pH set point and number of 2-16operating pumps were returned to normal levels (pH 5.6 and four pumps). The average 

### S0 2 removal efficiency was about 98.4% for this test.

Test 10, the final parametric test, was conducted after the formate concentration in the test module reaction tank was increased to 3800 ppm. With the pH set point at 5.6 and four pumps operating, 

### S02 removal increased to 99.4%


### 2.4.4 S02 

### Removal Performance Correlations

Absorber performance can be approximately described by the following expression derived from the "two-film" theory of mass transfer:

where: Number of Transfer Units (NTU) = ln 

### (S02

### ijS0 20u 1 ) = K* 

### NG

SOzin and 

### S0 2

### out = inlet and outlet 

### S0 2 concentrations; K (lblhr-ft 2) = average overall gas-phase, mass-transfer coefficient; A (ft2 ) = total interfacial area for mass transfer; and G (lb/hr) =total gas flow rate. 

### (2-1)

It is assumed in the above expression that the equilibrium partial pressure of 

### S02 above the FGD liquor is small compared with the inlet and outlet flue gas 

### S02 concentrations.

The overall coefficient K can be expressed as a function of two individual coefficients, 

### kg and 

### k 1, that represent mass-transfer rates across the gas and liquid films, respectively: 

### (2-2)

Where His a Henry's Law constant, and <I> is the liquid-film "enhancement factor" that includes the effects of changes in liquid alkalinity on the 

### S02 mass-transfer rate. For a given absorber, 

### 2-17operating at constant gas and liquid flow rates, NTU will be a function of slurry pH because of the effect of pH on the enhancement factor and, hence, on the value of K. NTU will also be a function of additive concentration for the same reason.
The form of Equation 2-2 suggests that the effects of increasing pH and additive concentration will diminish at some point when Hlk1 

### 4> becomes small compared with 

### 1/kg. This is referred to as "gas-film-limited" mass transfer. When this point is reached for a given absorber, there is no further benefit to increasing the additive concentration.
Equation 2-1 shows that NTU should be inversely proportional to gas flow rate (if the product of K*A is independent of gas velocity) and proportional to liquid flow rate (if A is proportional to liquid flow rate). The S0 2 removal performance data from the baseline and parametric tests have been used to examine the actual effects of L, G, pH, and formate concentration on NTU. During the baseline and parametric tests, performance was measured at controlled levels of slurry pH, slurry flow rate (number of pumps), and formate concentration. In addition to these controlled variables, the inlet S02 concentration and flue gas velocity in the test module varied throughout the tests. The detailed test data from Tables A-1 and A-2 were analyzed using
a non-linear least-squares curve fit routine to examine how these uncontrolled changes in test conditions affected S0 2 removal efficiency. This calculation showed that NTU varied with inlet S02

### .o.zs, and G.o· 3 •
The observed effect of gas velocity on NTU is less than predicted based on

· Equation 2-1, unless the product K* A increases significantly with increasing gas velocity. In

practice, for the spray tower absorber used in the Kintigh FGD system, an increase in flue gas velocity will increase the "A" term in Equation 2-1 because the velocity of small droplets through the absorber will decrease with increasing gas velocity and therefore increase their contribution to surface area. It is also possible that the increase in relative velocity between the flue gas and droplets increases K because of increased turbulence at the droplet surface. 2-18Another way that flue gas velocity can affect performance is through its effect on flue gas distribution in the absorber. The CEM traverse data showed that gas distribution appears to improve with increasing gas velocity. This could also contribute to the apparent increase in 

### K* A with increasing gas velocity.

In order to examine the effects of the controlled variables, the NTU data from Tables A-1 and A-2 were adjusted to a constant gas velocity of 

### 9 ftls and a constant inlet 

### S02 concentration of 1600 ppm using the observed dependence of NTU on these variables. Figure 2-3 shows the effect of formate concentration on adjusted 

### NTI1 for tests at pH 5.6 with three, four, and five pumps operating. As seen in previous tests with organic acid aClditives at other FGD systems, much of the relative increase in mass transfer is obtained over the range from 0 to 1000 mg!L formate.
Figure 2-3 also illustrates the relationship between NTU and recycle slurry spray rate. Comparing the three-pump and five-pump data, NTU is seen to be less than proportional to the slurry spray rate (L), which indicates that droplet surface area does not increase proportionately with increasing spray rate. At Kintigh, NTU was proportional to L 0

·65 • Results from some of the other absorber types in this project showed that NTU was directly proportional to L. Apparently, droplet agglomeration or other effects in the Kintigh spray tower reduce the effectiveness of increasing slurry spray rate.
Figure 2-4 shows the effect of slurry pH on NTU for tests with approximately 1000 mg/L formate and three or five pumps operating.


### 2.5 Results of Slurry Sample Chemical Analyses
2.5.1 Solid-Phase Analyses

Detailed results of solid-phase analyses for the baseline and parametric test slurry samples are included in Appendix A, Tables A-3 and A-4. These results were used to calculate 2-196

5

4

2

1 0 --.- 3 Pumps

### ~ 4 Pumps --..- 5 Pumps 

# I

S02 Removal

-------------------------- ---------------**~%**

- --------------------------------------- 90%

500 1000 1500 2000 2500 3000 3500 4000 

### Formate Concentration (mg!L) Figure 2-3. 

### Adjusted NTU vs. Formate Concentration for Tests at pH= 5.6

2-20

# -**~** 

### .... 

## = 

## e "" Q**~**

### ~ ,......,**~** 

## e

= 

## = Q N 

## = 0 

## =**~**

### ~ 

### 0

N 

### 0 00 l'7..l 

## e 

# - g. 

# = g. 

# - = ........ 

## =**~** \C**~** E-1

### ~ 

# z """' Cl\ Q


### .... "CS**~** 

## .... ell 

## = :s < '-' 5.0

4.5

4.0

3.5

"3.0

2.5

2.0 5.0 • 3 Pumps 0 5 Pumps 

# I

S02 Removal

----------------------------------- ------ 99% 

### oo 0
98% 

# •

---------------------- 95%


# • 90%

5.2 5.4 5.6 5.8 6.0 

### Slurry pH Figure 2-4. Adjusted NTU vs. pH for Tests with 1000 ppm Formate

2-21limestone utilization and sulfite oxidation, which are important process performance parameters. Results are briefly summarized here.

Calculated limestone utilization values from Table A-3 for the baseline tests have been plotted as a function of slurry pH in Figure 2-5. This curve is typical of results seen at the other limestone FGD process test sites. At the low end of the operating pH range, utilization gradually decreases with increasing slurry pH. Then, at the high end of the operating pH range, where the liquor is nearly saturated with respect to calcium carbonate, utilization falls off very rapidly. In Figure 2-5, it can be seen that the results for Baseline Test 6 do not lie on the fitted
curve because of a pH measurement problem during this test.

Limestone utilization results from the sodium formate parametric tests are plotted
versus slurry pH in Figure 2-6. Utilization results for the baseline tests from Figure 2-5 are also shown as a curve fit to those data. This comparison shows that limestone utilization data for the parametric tests are very scattered. Duplicate carbonate analyses showed very good analytical data quality. Therefore, the scatter in the data is most likely due to pH measurement or slurry sampling problems (see discussion in Appendix A).

Calculated sulfite oxidation percentages from Table A-3 for the baseline tests averaged about 3.8%. There appears to be a slight decrease in oxidation percentage beginning with Baseline Test 6. However, only the solids from Test 1 would have been expected to reach a steady-state composition corresponding to conditions for that particular test.

Sulfite oxidation percentages during the parametric tests averaged 4.7%, which is slightly higher than the 3.8% average for the baseline test solids. On the average, the unit load
was significantly lower during the parametric tests, so a slight increase in oxidation (caused by higher excess air in the flue gas) is not surprising. There appears to have been a slight decrease in oxidation during Parametric Test 9 compared with earlier tests, but the decrease was small. There was also an increase in thiosulfate concentration in the recirculating liquor between Tests 8 and 9 (see Liquid-Phase Analyses Table A-6), which could account for this change. 2-22100
95



# - 90**~** '-" 

# = 85 Q 

# .... 

# - c= N 

# .... 

# - .... 

# - 80 I:J**~** 

# = Q 

# - 75 l:ll**~** 

### 5



# ....**~** 70
65
60 4.8 5.0 Om:J

# ~ Test6 pH Error

5.2 5.4 5.6 

### Slurry pH

Figure 2-5. Baseline Test Limestone Utilization vs. Slurry pH

2-23 5.8 6.095

90 0



# -**~** .._, 85 

# = Q 

# ·- -;; N 

# ·- 

# - ·- 

# - 80 ::;J**~** 

# = s !;1.:1 

# 5 75 

# ·-**~** 70

65 5.0 5.2 0 0 0 0 ld 0 

# ' 0 0 

### Baseline 0 

### Results 0 0 DOD 0 0 0 0

0



### 5.4 5.6 5.8 

### Slurry pH

Figure 2-6. Parametric Tests Limestone Utilization vs. Slurry pH

2-24 0
0 0
0

6.0

### 2.5.2 Liquid-Phase Analyses

Detailed results of liquid-phase analyses for the baseline and parametric test filtered slurry samples are shown in Appendix A, Tables A-5 and A-6. Calculated relative saturations are also shown in the liquid-phase analytical results table. Relative saturation for a specific compound is defined as the activity product for the ionic components in solution divided by the solubility product. These values were obtained using Radian's Aqueous Chemical And**~hysical ~roperties**  (ACAPP) computer routine, which calculates the equilibrium distribution of chemical species using the analytical results as inputs.

Of greatest interest in an inhibited-oxidation FGD system such as this is the gypsum relative saturation. The objective of inhibiting oxidation with sulfur (which reacts to produce thiosulfate in solution) is to prevent scaling by maintaining the gypsum relative saturation below 1.0. Previous research has shown that all of the sulfate produced by oxidation of absorbed 

### S0 2 will precipitate as a solid solution with calcium sulfite, up to the point where the system oxidation percentage reaches about 15%. Above 15% oxidation, the balance of the sulfate (beyond 15% of the 

### S02 absorbed) will precipitate as gypsum.
The results in Table A-5 show that the baseline liquor samples all had gypsum relative saturations well below 1.0. These results are consistent with the solids analyses, which showed that the baseline test oxidation percentage was well below 15%. The gypsum relative saturations decreased somewhat during and following Baseline Test 6, consistent with the solids analyses, which showed a corresponding decrease in sulfite oxidation percentage. Table A-6 for the parametric tests again shows that estimated gypsum saturations are well below 1.0, but they
are slightly higher than for the baseline tests. This is consistent with solids analyses, which showed slightly higher sulfite oxidation percentages for the parametric tests.

The parametric liquid analyses results can be compared with the baseline values to examine effects of the sodium formate additive on process chemistry. There does not seem to be any change in process chemistry that can be specifically related to the formate additive other than 2-25the obvious increase in sodium concentration. There was about a 20% increase in dissolved magnesium and a 15% decrease in dissolved chloride between the baseline and parametric tests. The combined result of these changes in sodium, magnesium, and chloride concentrations was to lower the dissolved calcium concentration substantially in the parametric tests compared with the baseline tests.

Concentrations of 32 elements were also determined in selected samples using inductively coupled plasma emissions spectroscopy (ICPES). These data are summarized in Table A-7. There were no remarkable differences in the results for the baseline and parametric tests.


### 2.6 Sodium Formate Consumption Test Conditions and Results

The parametric tests were followed by a steady-state sodium formate consumption test. The cost-effectiveness of using additives to enhance S0 2 removal depends both on the performance increase and the consumption rate of the additive. The objective of the consumption test was to measure the amount of sodium formate required to maintain high S02 removal efficiency with the entire FGD system. Sodium formate was added continuously to the entire system for a period of six days, and the consumption rate was determined by material balance.


### 2.6.1 Consumption Rate Calculation

The consumption rate of sodium formate was determined by performing a liquidphase formate ion mass balance on the FGD system. This required monitoring sodium formate addition rate, formate losses with liquor adhering to the filter cake, and changes in liquid-phase formate inventory over the duration of the test.
The sum of the following terms represents the total loss of sodium formate from the Kintigh FGD system during the consumption test: 2-261. Solution loss

- formate lost in liquor adhering to the filter cake. Liquor blowdown from the FGD system would also contribute to the solution loss, but there was no separate liquor blowdown stream from this FGD system. 2. Degradation

- formate lost due to chemical or biological oxidation of formate to produce C02 and water. 3. Coprecipitation loss- formate lost by incorporation into the calcium sulfite crystal structure. 4. Vaporization- formate lost by vaporization (as formic acid) into the flue gas.
The solution loss can be calculated for a given system based on the S0 2 removal rate, additive concentration, and filter cake moisture content. The sum of losses 2, 3, and 4 is normally termed the "nonsolution loss." The nonsolution loss is less easily predicted. The total nonsolution loss can be determined by subtracting the total solution loss from the total consumption, but the individual terms in the total nonsolution loss can only be estimated. Using the terms defined above, the following form of the system mass balance gives the average nonsolution loss rate for a given test period:

Formate nonsolution loss (lb) = Formate added (lb)

- Formate inventory change (lb)

- Formate solution loss (lb)

The formate addition term was obtained by measuring the change in the sodium formate tanker level. The solution loss term was obtained by multiplying the total filter cake production for a given test period by the average filter cake moisture content and filtrate formate concentration. The inventory change term was obtained by monitoring changes in formate concentration in all of the system vessels throughout the test. Details of the formate consumption test material balance are included in Appendix B.

2-27The additive nonsolution loss rate is normally reported on an 

### S0 2 removal basis (lb of formate or sodium formate per ton of 

### S02 removed). 

### S02 removal in the FGD system for a given test period was calculated using hourly averages for unit load, an assumed gross heat rate, and inlet and outlet 

### S02 concentrations (in lb 

### S0 2 per million 

### Btu heat input) measured by the certified inlet and stack continuous emissions monitors (CEMs). As a check on this estimate, 

### S02 removal was also estimated from the amount of limestone used by the FGD system.


### 2.6.2 Results
Sodium Formate Consumption

Table 2-3 is a summary of the liquid-phase formate material balance for the duration of the consumption test from 917/94 to 9112/94. In this calculation, total formate consumption is divided into "solution losses," which includes formate leaving the system with the filter cake moisture; and "nonsolution losses," which includes all other loss mechanisms such
as vaporization, degradation, and precipitation.
During the 120-hour test duration between the initial and final formate inventories, a total of 13,380 lbs of formate (20,220 lbs of sodium formate) was added to the system. The average feed rate was 168lblhr as sodium formate. The total system liquid-phase formate inventory decreased by 1,420 lbs out of a total of about 40,000 lbs. The total formate consumption for the test (the addition term plus the inventory decrease) was 14,800 lbs. A total of 1,700 lbs or 11% of the total formate consumption was accounted for by formate lost from the system in the liquor adhered to the filter cake solids. This 11% of the total formate consumption represents the solution losses. The remaining consumption (13,100 lbs of formate) represents the
sum of the nonsolution losses.
During the test, a total of 1,346 tons of 

### S0 2 were removed from the flue gas by the FGD system. The 

### S0 2 removal efficiency averaged about 97% during periods when the bypass damper was closed. The average formate concentration in the module reaction tanks was about 2-28Table 2-3 Summary of Sodium Formate Consumption Test Results a

Total added (lbs) 13,380 Total liquid-phase inventory change (lbs) -1,420 Total consumption (lbs) 14,800 Total loss with filter cake liquid (lbs) 1,700 Total non-solution loss (lbs) 13,100 Total 

### S02 removed (tons) b 1,346 Total solution loss rate (lb/ton 

### SOz) 1.3 Total non-solution loss rate (lb/ton 

### S0 2) 9.7 Total consumption rate (lb/ton 

### S0 2) 11.0 Average feed rate (lblhr) 111 Initial average module concentration (mg/L) 1,045 Final average module concentration (mg/L) 1,120 97

a Results calculated between the 917 and 9/12 inventories. b 

### S02 removal based on the CEM data and boiler load.

2-29 20,220 -2,150 22,360

2,570 19,790

1,346 2.0 14.7 16.6 168 1,580 1,690 971080 mg/L. Expressed on an S02 removal basis, the total additive consumption rate was 11 lb/ton 

## so2 as formate or 16.6 lb/ton 

## so2 as sodium formate. The solution and nonsolution loss rates were 1.3 and 9.7lb/ton S02 , respectively, on a formate basis and 2.0 and 14.7lb/ton on a sodium formate basis.

An error propagation analysis was done to estimate the uncertainty in the formate consumption results using the procedure outlined in ANSI/ASME Power Test Code 19.1-1985, "Measurement Uncertainty." The uncertainty analysis indicated that the total calculated sodium formate consumption (16.6lb sodium formate/ton S02 removed) is accurate to about ±3.5lb/ton
or ±21% at the 95% confidence level. The nonsolution loss term (14.7lb sodium formate/ton S02 removed) is accurate to ±3.6lb/ton or ±25%.


### Relative Importance of Different Loss Mechanisms

The above sodium formate consumption measurement was based on the liquidphase material balance. The results of filter cake solids analyses from the consumption test and flue gas analyses from the parametric tests can also be used to estimate the relative contrib1,1tions of precipitation, vaporization, and degradation to the total nonsolution loss.
Analyses of daily filter cake samples obtained during the consumption test showed an average solid-phase formate concentration of 0.8 mg/g of dry solids, or 0.08 weight percent. The theoretical rate of filter cake solids production is about 2.2 tons dry filter cake/ton of S0 2 removed (at 90% limestone utilization, 3% oxidation, neglecting fly ash and other inerts). Using these data, the average loss rate of formate with the solids would be 3.5 lb formate/ton of S02 removed (5.3lb/ton as sodium formate), which accounts for about 36% of the total nonsolution loss rate.

The flue gas was also analyzed for formic acid during several of the formate parametric tests. In many cases, the formic acid concentrations were less than the estimated 0.1 to 0.2 ppm detection limit for the sample. The maximum flue gas formic acid concentration 2-30measured was about 1 ppmv during Parametric Test 1. At full load, the flue gas flow rate at Kintigh is about 1,700,000 scfm, and the S02 removal rate averages about 11 ton/hr. A flue gas formic acid concentration of 1 ppmv corresponds to a vaporization loss rate of about 1 lb formic acid/ton of S02 removed. This loss rate accounts for a maximum of about 10% of the total nonsolution loss rate. The actual formate vaporization loss rate may have been much less than 10% of the nonsolution loss rate.

The formate degradation rate cannot be measured directly. However, based on measurement of the total nonsolution loss rate and estimates for two of the three nonsolution loss mechanisms, by difference, the degradation loss rate accounts for about 55 to 65% of the total nonsolution loss rate.


### Results of Consumption Test Slurry 

### Analyses

Tables B-2 and B-3, Appendix B, summarize the results of solid-phase and liquidphase analyses for slurry samples obtained during the consumption test. The solid-phase results show that the FGD system continued to operate at very low oxidation percentages: an average of about 2.5% for the long-term test samples, compared with 3.8% for the baseline tests and 4.7% for the parametric tests.

The average system load for the long-term tests was similar to that for the baseline tests, but the thiosulfate concentration in the liquid (see Table B-3) averaged 750 mg/L during the long-term test compared with 240 mg/L for the baseline tests and 320 mg/L for the parametric tests. Therefore, the lower oxidation percentages seen during the long-term test may be a result of higher thiosulfate concentration. An oxidation-inhibiting effect of sodium formate additive
was seen at another site in this project (SWEPCo's Pirkey FGD system), but the oxidation data from Kintigh are too confounded by unit load and thiosulfate concentration to determine if there
was a similar effect.

2-31Limestone utilization results from Table B-2 have been plotted for comparison with the baseline test results in Figure 2-7. These results did not exhibit the wide scatter that was seen during the parametric tests. The comparison in the figure indicates that the sodium formate additive had no significant effect on limestone utilization.
Referring to Table B-3, the liquid analyses for the long-term tests show trends that
are consistent with the solids analyses. The lower oxidation during the long-term tests resulted in lower liquid-phase sulfate concentrations and lower gypsum relative saturations compared with the baseline and parametric tests.


### 2.7 Effect of Sodium Formate Additive on Solids Dewatering Properties

Tests were performed to examine the effect of sodium formate on other solids properties. If sodium formate is used as a performance-enhancing additive, changes in solids properties caused directly or indirectly by this additive could affect the operation of dewatering equipment.

Three methods were used to examine solids samples from Module E as part of this test program: settling tests, filter leaf tests, and scanning electron microscopy (SEM). Settling tests were performed on site using lower-loop slurry samples to ascertain the effect of sodium formate on sedimentation properties. The bulk settling procedure detailed in Method C2 of EPRI' s FGD Chemistry and Analytical Methods Handbook was followed (rake action was not simulated). Filter leaf tests, as described in Method C3 of EPRrs Handbook, were performed to
assess changes in the solids filtration rate and solids water retention under vacuum filtration. Finally, SEM was used qualitatively to examine changes in crystal structure.


### 2.7.1 Settling Test Results

Batch settling tests were performed on slurry samples from the Module E primary reaction tank from which slurry is bled to the dewatering system. These tests determine both 2-32100
95
D
,-... 90**~** ..._, 

# = Q 85 

# ·- ....**~** N 

# ·- 

# - ·- .... 80 p**~** 

# = .s 75 riJ 

# 5

....**~** 70
65
60 4.8 

# • • • 0 0 0 

# euan 

# • D 0

# ~**~** D



# •

D Baseline Tests 

# • Long- Term Test

5.0 5.2 5.4 5.6 5.8 

### Slurry pH

Figure 2-7. Comparison of Baseline and Long-Term Tests Limestone Utilization

2-33 6.0settling rates and final solids underflow concentrations. Settling rates are reported as the thickener unit area (UA, ft2/ton/day) required to reach a 30 wt.% underflow concentration. Lower unit areas correspond to slurries that settled faster.
Settling test results are summarized in Table 2-4. Four settling tests were done during Baseline Test 1. The average calculated unit area of about 2 ft 2 /ton/day indicates a relatively fast-settling sulfite sludge, characteristic of inhibited-oxidation limestone FGD systems with very low oxidation percentages.

A total of eleven settling tests were done during the parametric tests: three during each of the two-day tests (Tests 1, 2, and 9) at increasing formate concentrations, and two extra tests with 1000 ppm formate in the test module. Three additional settling tests were done during the consumption test. The parametric and consumption test results are also summarized in Table 2-4 along with the baseline results. Also, shown in the table are average unit loads for a 48-hour period prior to each of the settling tests.

The first settling tests for the parametric test series were done during Test 1, after 500 ppm formate had been added to the test module. The results of these tests showed higher unit areas compared with the baseline results. The settling rate decreased markedly over the next few days, and the unit area increased to an average of 17 ft2 /ton/day during Parametric Test 2 with 1000 ppm formate in the test module reaction tank. Over the same time period, however, the unit was operated at a much lower load than usual, so that the observed increase in unit area may have been a result of increased oxidation percentages due to higher excess air in the flue gas. The unit returned to sustained high-load operation over the weekend prior to Test 9, and the settling rate increased (unit area decreased) to levels less than that of Parametric Test 1 and approaching that of the baseline tests. Therefore, it is unlikely that formate alone affected the settling rate to any great extent.

2-34B-1 Baseline pH5.6

P-1 500mg/L formate pH5.6 P-2 1000mg/L formate pH5.6 Extra 1000mg/L formate, pH 5.8 Extra 1000mg!L formate, pH 5.6 P-9 1500mg!L formate pH5.6 C-1 1040mg!L formate, pH 5.6 C-2 1180mg/L formate, pH 5.6 1250mg!L C-3 5.6 7/18/94 7119/94 7119/94 7/19/94 8/22194 8/23/94 8/23/94 8/25/94 8/25/94 8/25/94 8/26/94
8/27/94
8/29/94 8/29/94 8/29/94 9nt94
9/9/94
9/12/94 Table 2-4 Results of Settling Tests

1530 NA 0800 NA 1340 564 1435 573 1200 651 1200 600 1310 598 0820 410 1310 412 1610 424 1330 533
0900 632
0730 638 1125 631 1620 624 1405 NA
1325 664b
1140 647

a Initial slurry solids content estimated from NYSEG slurry density data. b Thirty-hour average load prior to test. NA 

## = Data not yet available.

2-35 9.0 1.9 65 9.7 2.3 60 11.2 1.9 61 10.6 2.2 64 10.9 2.9 54 9.3 4.4 51 9.3 4.8 49 7.8 18 39 7.8 20 38 10.4 12 40 10.4 11 43
10.9 11 43
9.0 3.9 52 8.9 3.3 49 9.0 2.7 55 7.0 2.9 46
11.3 1.9 56
10.1 2.0 50Settling tests done during the consumption test yielded estimated unit areas about the same as for the baseline results. The unit was operated at sustained high load throughout the consumption test. This confirmed that sodium formate had little effect on slurry settling rate.


### 2.7.2 Filter Leaf Tests

The results of the filter leaf tests are summarized in Table 2-5. The results include "form filtration rate (lblhr-ft2)," which is an indicator of the potential vacuum filter throughput per unit filter cloth area, and the final filter cake moisture contents under standard drying conditions. fu Table 2-5, the test designation "B-1" refers to Baseline Test 1, and the designation "P-1" refers to Parametric Test 1.

The form filtration rates show a trend that follows the settling test results. That is, the filtration rates for the baseline and initial parametric test are similar, but the filtration rate decreased substantially during the second parametric test. By the end of the parametric tests, h0wever, the filtration rate was at least as high and possibly higher than the initial rate for the baseline tests. Again, this trend is most likely related to the unit load and sulfite oxidation percentage rather than to the sodium formate additive.


### 2.7 .3 Scanning Electron Microscope (SEM) Photographs
Figures 2-8a and b through 2-11 a and b are SEM photographs of slurry solids samples from the two-day baseline test (Baseline Test 1) and from the three two-day parametric tests at increasing formate levels (Parametric Tests 1, 2, and 9). These photos reveal no significant changes in crystal habit with sodium formate additive.

2-36

### Table 2-5 Results of Filter Leaf Tests

B-1 7119/94 1045 520 69 B-1 7119/94 1345 530 70 B-1 7119/94 1520 450 71 P-1 8/23/94 1200 530 72 P-1 8/23/94 1500 550 

### 71 P-1 8/23/94 1806 560 

### 69 P-2 8/25/94 0815 270 70 P-2 8/25/94 1300 235 69 P-2 8/25/94 1626 210 72 P-9 8/29/94 0800 520 68 P-9 8/29/94 1124 530 70

2-37

### Figure 2-Sa. Solids from Baseline Test 1 (500x)

Figure 2-8_1>. Solids from Baseline Test l (1000x)

2-38

### Figure 2-9a. Solids from Parametric Test 1 (500x)

Figure 2-9a. Solids from Parametric Test 1 (lOOOx)

2-39

### Figure 2-lOa. Solids from Parametric Test 2 (500x)

Figure 2-lOb. Solids from Parametric Test 2 (lOOOx)

2-40

### Figure 2-lla. Solids from Parametric Test 9 (500x)

Figure**2~11b.** 

### Solids from parametric Test 9 (lOOOx)

2-41

### 2.8 Other Process Data
2.8.1 Control Room Data

Process data were recorded during the baseline, parametric, and formate consumption tests by the plant data acquisition system and from control-room indicators. These data are summarized in Appendix C, Tables C-1 and C-2.


### 2.8.2 Recycle Pump Slurry Flow Rate Measurements
Recycle pump slurry flow rates were measured using an ultrasonic Doppler-effect flow meter. Each pump was tested several times during the baseline and parametric tests. Pump motor current and discharge pressures were also recorded. Results are summarized in Table 2-6. The flow measurements were reproducible, and the recorded flows agreed well with those expected based on the 10,900 gpm nominal capacity rating for these pumps.


### 2.8.3 S0 2 

### Removal Data for the Consumption Test

Overall FGD system 

### S02 removal efficiencies measured during the consumption test are summarized in Table 2-7. In order to measure overall 

### S0 2 removal efficiency during the consumption test, it was necessary to close the system bypass damper so that the system efficiency could be measured using the inlet and stack CEM data. The normal operating procedure at Kintigh includes sufficient flue gas bypass to maintain an outlet flue gas temperature of about 131 °F so that excess condensation does not occur in the scrubber outlet plenum. The data in Table 2-7 represent average removal efficiencies for one-hour periods each day during which the bypass damper was closed. With the bypass damper closed, the average 

### S0 2 removal was nearly 97% with the unit operating at essentially full load. The average reaction tank formate concentration was about 1130 mg/L during periods when the bypass damper was closed. The 

### S0 2 removal efficiency during the long-term test was slightly lower than the 98% level expected based on the parametric tests with a single module. However, 2-42Table2-6 Results of Recycle Pump Flow Measurements

1 9850 9700 9650 9700 10000 9500 9700 45 NA 2 10600 10500 10600 10500 10500 10500 10500 42 36 3 11650 12000 11300 11400 10950 10950 11400 44 34 4 10500 10000 9800 9750 10000 44 38 5 10250 10200 10400 10350 10250 10300 42 37

2-43Table 2-7 802 Removal Efficiency During Consumption Test



### 9/8/94 1100 675 1100 0.14 96.7 9/9/94 1500 693 1120 2.88a {}.08 97.2 9110/94 1000 673 1190 4.35 0.15 96.6 9/11/94 1100 668 1110 4.51 0.17 96.2 677 1130 96.7

a 

### Inlet S0 2 

### estimated due to CEM malfunction.



### 2-44performance differences among the modules or leakage of a small amount of inlet flue gas through the bypass damper could easily account for the overall FGD system S02 removal efficiency being slightly lower than the measured Module E efficiency.

2-45

### 3.0 FGDPRISM MODELING RESULTS

The FGD PRocess Integration and S,imulation Model (FGDPRISM) is a computer program that simulates the performance of wet lime and limestone FGD systems. The model
was calibrated to NYSEG's Kintigh Station with data collected during two of the baseline and
one of the parametric tests. Mter calibration, the model was used to predict performance for the remaining tests and to investigate some additional options that were not tested. The performance of a finer limestone grind was predicted, and the option of operating the unit at current S02 removal levels with formate additive and fewer recycle pumps in service was evaluated. The results of the model calibration and the process simulations are summarized below. Detailed results are included in Appendix D.


### 3.1 FGDPRISM Calibration Results

The FGDPRISM model is calibrated to test results by adjusting several parameters. The parameters are adjusted to achieve the best fit with respect to liquid-phase chemistry, limestone utilization, and S02 removal efficiency for the cases used in the calibration. For the Kintigh FGD system, the main parameters of the calibration are:

• Limestone reactivity;

• Gas- and liquid-film thicknesses for the spray droplets; and

• Calcium sulfite/sulfate solid solution precipitation rate.
The limestone reactivity is adjusted by changing a variable called the surface area factor and the limestone reaction rate constant (k) to match the observed limestone utilization and pH in the reaction tank. The gas-film and liquid-film thicknesses are adjusted to match the masstransfer characteristics of the absorber. The calcium sulfite/sulfate solid solution precipitation rate constant is adjusted to match predicted and measured relative saturation values for solid calcium sulfite and sulfate compounds.
3-1In addition to these primary calibration parameters, several other input values are adjusted to match the liquid chemistry present in the absorber. For example, the HCl content of the flue gas is varied to match the chloride concentration in the slurry and the limestone MgC0 3 solubility and makeup water sodium and magnesium contents are varied to match the magnesium and sodium concentrations in the slurry. Figure 3-1 compares predicted versus actual S0 2 removal efficiency for the calibrated FGDPRISM model.


### 3.2 Predictive Simulations

The calibrated model was used to make several predictive simulations to evaluate
some conditions that were not actually tested. First, the model was used to evaluate the effect of limestone grind on S0 2 removal efficiency.

A screen size analysis of the limestone reagent used at Kintigh showed that the current grind is relatively coarse; 52% 

### < 200 mesh, and 42% 

### < 400 mesh. By comparison, the "standard" grind used at EPRrs Environmental Control Technology Center (ECTC) is about 93% 

### < 200 mesh and 85% 

### < 400 mesh. (Note that although the ECTC is located at the Kintigh station, the pilot- and full-scale FGD systems have independent limestone supplies and each has its own limestone grinding equipment.) Experience has shown that limestone grind can have a significant effect on S0 2 removal efficiency at constant limestone utilization. The calibrated FGDPRISM model was used to predict performance for the Kintigh FGD system using the ECTC limestone grind instead of the measured grind. Under those conditions, FGDPRISM predicted that S0 2 removal efficiency at Kintigh could be increased to nearly 97% with four pumps operating. The predicted limestone utilization was 84%, a slight decrease from the baseline level of 85%, at an operating pH of about 5.8.

3-2100 0 Baseline 

# • Parametric 

### Cil 90 0



# - '$. 

# -- - =**~** 80 

## a**~** 0**~** 

### 0 V1 "0**~** 70 

# -**~** 

# .... "0**~** 

# -**~** 60**so~~~~~._._._~~~~~~~~~~~~~~~~~~** 50 60 70 80 90 100 

### Observed 

## so2 Removal ( 0 /o)



### Figure 3-1. Kintigh FGDPRISM Calibration: Predicted vs. Observed Removal

3-3The model was also used to predict limestone utilization for operation at the current S0 2 removal level with a finer grind. Using the ECTC grind as input, FGDPRISM predicted that the current S02 removal efficiency could be maintained with limestone utilization increasing from the baseline 85% to about 98%.

The calibrated model was also used to evaluate the option of maintaining current 

## so2 removal efficiency (with partial bypass) using sodium formate additive to permit operation with fewer spray pumps. With three spray pumps per module, the model predicted that only 125 mg/L formate would be-needed to maintain current S02 removal (88% removal in the modules, 85% overall removal including partial bypass). With two spray pumps per module, 670 mg!L formate would be needed. The cost effectiveness of these modeled conditions is discussed in the next section.

3-4

### 4.0 ECONOMIC EVALUATION

Performance data from the baseline, parametric, and long-term sodium formate consumption tests were used to evaluate the economics of upgrades to increase S0 2 removal efficiency with the current Kintigh FGD system configuration. Some additional operating cases that were not tested were evaluated based on performance predicted by the calibrated FGDPRISM model. Results of these economic evaluations are presented in this section.


### 4.1 Upgrade Options and Cost Basis
Options to upgrade the 

## so2 removal performance at Kintigh include operating without flue gas bypass at otherwise current conditions and/or adding sodium formate to the system. A number of upgrade cases were considered involving each of these options separately and in combination. For the options that included sodium formate addition, cases were considered with either three or four recycle pumps per modules in service and with a range of pH set points and formate concentrations. Table 4-1 summarizes the system design basis, cost components, and other assumptions necessary for evaluating these options.

The maximum gross output of the Kintigh Station is about 700 MW. Based on 1985 to 1993 data, an average of 1,794,000 tons per year of coal with a sulfur content of 2.33%
were burned at Kintigh. The average heating value of the coal was about 13000 Btu/lb. The average reported capacity factor was about 85%. For the economic evaluation, this capacity factor was approximated by assuming that the unit operates 8000 hours per year with an average load of 660 MW. The average flue gas flow rate at 660 MW was estimated by combustion calculation to be 7.3 million lb/hr.

The average equivalent S0 2 content of the fuel was 3.58 lb/million Btu, and the system outlet S0 2 was typically maintained at 0.52lb/million Btu. Based on these 1985 to 1993 average data, the baseline annual amount of S0 2 removed is about 71,000 tons, and the baseline

4-1

### Table 4-1 Economic Basis for Kintigh S0 2 

### Removal Upgrade Options Maximum Continuous Rating 708MWgross Capacity Factor 86% (8000 hours at 660 MW avg.) Average Flue Gas Flow 7.3 million lblhr Average Fuel Sulfur Content 3.58 lb/million Btu Average Fuel Heating_ Value 12990 Btullb Current Average Outlet S0_2 0.52 lb/million Btu Current SO, Removal 71,000 tons/yr Additional S0 2 Available for Removal 12,500 tons/yr_ Capital Cost of Sodium Formate System $300,000 for 100 lblhr Annualization Factor 0.17 Delivered Cost of Sodium Formate $0.24/lb, $0.30/lb Cost of Power $0.017/k.Whr Sodium Formate Consumption Rate 16.6lb/ton so2 at 1130 mg!L Cost of Prepared Limestone $12.50/ton Cost of Additional Sludge Disposal $7.50/ton fucrease in System AP to Treat all Flue Gas 0.6 in. H20 Decrease/fucrease in System AP per Spray Pump 0.2 in. H 2 0 Fan Efficienc;y_ 80% Avera.ge Recycle Pump Power Consumption 280kW Current A verag_e Limestone Utilization 85%

4-2emissions are about 12,500 tons/year. These baseline emissions represent the additional amount of S02 available for removal by operating the FGD system at higher efficiency.

The capital cost of a sodium formate additive system sized for 100 lblhr was previously estimated to be about $300,000. This cost was adjusted as a function of capacity ratio using an exponent of0.15. An annual capital recovery factor of 0.17 was used. The delivered cost of sodium formate supplied by Perstorp during the test program was $0.24/lb. A cost of $0.30/lb was also used in the evaluation to look at the sensitivity of the results to the additive price. The results of the sodium formate consumption test indicated that the total consumption with 1080 mg!L formate in the reaction tanks was 16.6lb/ton of S02 removed. Based on results from pilot-scale tests at EPRI's ECTC, sodium formate consumption should be directly proportional to concentration. A linear relationship between sodium formate concentration and consumption was, therefore, assumed for the economic evaluation.

Increases in system S02 removal will increase several operating costs, including limestone purchase and waste disposal costs. These costs were derived from data provided by NYSEG. Additional limestone reagent (prepared) was valued at $12.5/ton. The cost of dewatering and disposing of additional filter cake was estimated to be $7 .5/ton. Operation without flue gas bypass will increase FGD system pressure drop and fan power consumption. The average increase in overall system pressure drop due to treating all of the flue gas was estimated to be 0.6 in. H 20 based on data obtained during the consumption test. Operation with fewer recycle pumps will decrease system pressure drop. A decrease of 0.2 in. H 20 per spray pump taken out of service (in all operating modules) was estimated based on data obtained during the baseline and parametric tests. A fan efficiency of 80% was assumed, and the fan power was valued at $0.017/kWhr.

The limestone utilization at the normal pH set point was observed during baseline testing to be about 85%. Utilization values for other pH set points were estimated from the baseline data (Figure 2-5). 4-3

### 4.2 

### Results

The economic factors described above were included in a spreadsheet calculation that estimates the cost of additional tons of 

### S0 2 removed for various operating conditions and levels of removal efficiency. Table 4-2 summarizes the results of these calculations for the most cost-effective options. Additional details of the calculation and results for some other options are shown in Appendix 

### E, Table 

### E-1. The cost of additional 

### S02 removal was evaluated over a range of formate concentrations in each case to determine the optimum concentration. Only the optimum results are shown in the table. For higher formate concentrations than those shown in the table, the marginal cost of additional tons of 

### S02 removed became greater than the assumed value of allowances.

The first row of entries in Table 4-2 is based on current operational practice. The FGD system is operated with four modules and four pumps per module at a nominal pH set point of 5.6, and with 85% limestone utilization. The overall system 

### S02 removal is about 85% with partial bypass being used to control condensation in the absorber outlet plenum.

The first upgrade option in Table 4-2 is based on the option of closing the system bypass dampers, while maintaining FGD system operation at the current baseline conditions (pH 5.6, four pumps per module). Based on the temperatures of the inlet flue gas, scrubber module outlet flue gas, and the stack gas, the typical amount of flue gas bypass was estimated to be 3%. The individual module efficiency was assumed to be unchanged with the small additional gas flow. Closing the bypass damper increases the 

### S02 removal efficiency from 85 to 88%, removing an additional 2,500 tons/yr of 

### S02 •
The costs associated with this option include fan power for increased pressure drop across the system with the bypass closed, as well as reagent, limestone, and sludge disposal costs for the additional 

### S0 2 removed. The total cost increase is $128,000/yr, which results in an average cost of $51/ton of additional 

### S0 2 removed by closing the bypass damper.

4-4

### Table4-2 Economic Comparison of S02 

### Removal Upgrade Options

51 500 250 53 1940 960

97.8 85 10,640 810,000 76 1850 790

Maintain 94.8 85 8,140 672,000 83 1360 550 bypass add lOOOmgiL formate Maintain 85 85 0 (98,000) 

### NA NA NA current S0 2 removal with 2Pumps and 670mg/L formate Maintain 85 98 0 (224,000) 

### NA NA NA currentS0 2 removal with 4pumps and finer limestone grind 

## * Includes 3% partial bypass.Note that NYSEG chooses to operate with this small amount of gas bypass as a means of keeping the absorber outlet plenum dry. Operating with no bypass would result in wet conditions in the plenum. This wet operation would bring an associated potential for increased corrosion in the plenum and for "rainout" of acidic droplets from the stack. Capital upgrades such as adding more corrosion resistant materials of construction in the outlet plenum and adding droplet weirs in the stack could be implemented to decrease the potential for these problems. However, such upgrade costs were not estimated and were not evaluated in determining the cost effectiveness of closing the bypass.
Instead, several upgrade options have been evaluated with and without gas bypass. The difference between the projected value of S02 credits generated with and without gas bypass represents the approximate annual amount that would be available to invest in capital upgrades to improve operation with the bypass closed

..
For example, for this first option which includes no FGD system upgrades beyond closing the bypass damper, the additional S02 allowances removed would have an annual value of $250,000 if allowances are valued at $150/ton. If instead they are valued at $250/ton, the additional allowances would have an annual value of about $500,000. 

### In the first instance, where the S0 2 allowances have a value of $150/ton, then capital upgrades amounting to up to $250,000 annually may be cost effective if they would allow continuous closed bypass operation.

The next option in the table is to use a finer limestone grind (93% 

### < 200 mesh) at the same pH set point, also with the bypass closed and with the four-module, four-pump configuration. Under these conditions, FGDPRISM predicts that S02 removal efficiency should increase to 96.8%. With this substantial increase in removal efficiency, 9,840 additional tons of S0 2 are removed per year. The costs include additional fan power, reagent and waste disposal costs, plus an assumed cost differential ($1 00,000/yr) for operating the reagent preparation equipment at half of the current feed rate and for twice the current operating time to produce the finer limestone grind. The total cost of increased S0 2 removal using a finer limestone grind is

4-6

---------$521,000/yr or $53/ton for the additional 

### S02 removal. The net annual value of this option ranges from $960,000 to $1.94 million, depending on the assumed value of allowances.

The next option in Table 4-2 is to close the bypass and add 1000 mg/L formate to the FGD system, while maintaining the current baseline pH set point (5.6) with four recycle pumps per module operating and with the current limestone grind. With these conditions, 

### S02 removal efficiency should increase to 97.8%. This corresponds to 10,640 tons/yr of additional 

### S0 2 removed. Additional costs include fan power, reagent and waste disposal, plus the annualized capital cost of the additive storage system and the purchase cost of the sodium formate additive. The total annual cost for this option is $810,000, or an average of $76/ton of additional 

### S0 2 removed. The annual value of additional 

### S02 removed is about $1.85 million if allowances are valued at $250/ton and $790,000 if allowances are valued at $150/ton.



### As discussed previously, it is likely that NYSEG will not want to operate without partial bypass unless capital improvements are made. The next case evaluates the option of maintaining partial bypass, while adding formate to increase 

### S02 removal. This option was most cost-effective with four recycle pumps per module and 1000 mg!L formate. The overall system 

### S02 removal is 94.8% for this case, and the total annual value is $1.36 million (or $550,000 for $150 allowances). A comparison of the formate cases with and without partial bypass shows that closing the partial bypass can generate an extra $240,000 to $490,000/yr in allowance value. This is a significant potential revenue which might justify some capital improvements to permit operation without bypass.

The final two cases in Table 4-2 evaluate operation at the current 

### S02 removal efficiency with partial bypass. In the first of these, sodium formate is added to maintain 

## so2 removal with fewer recycle pumps. The required sodium formate concentrations (670 mg!L with two pumps per module) was predicted using FGDPRISM. The result shows that the fan and pump power savings exceed the cost of formate additive by nearly $100,000/yr.

4-7In the final option in Table 4-2, the current S02 removal efficiency (with partial bypass) is maintained with four pumps per module using a finer limestone grind to increase limestone utilization. For this case, FGDPRISM predicted that limestone utilization could be increased to 98% at an operating pH of 5.5. The net annual savings for this case exceeds $200,000 even after allowing $100,000 for increased reagent preparation labor, power, and maintenance costs.


### 4.2.1 Effect of Sodium Formate Additive Price on Results

Additional economic cases were run to evaluate the effect of increased additive cost on the upgrade options. Increasing the cost of sodium formate by 25% to $.30/lb did not change the relative rankings of the additive options. The optimum formate concentration for the normal-pH, four pumps per module case remained at 1000 mg/L with sodium formate at $0.30/lb, butthe net annual value of this option decreased by about $70,000.


### 4.3 Recommended Upgrade Option

Based on the results of the economic analysis and the available test data, the use of sodium formate additive at a level of 1000 mg!L with four recycle pumps per module and the bypass closed appears to be the best upgrade option. This would result in greater than 97% S02 removal, and remove an additional 10,000 tons of S0 2 per year. Under these conditions, the 10,000 additional tons/yr of S02 will be removed at an average cost of about $76/ton.
However, FGDPRISM predicts that use of a finer limestone grind might be a good approach, provided that the existing reagent preparation equipment can be adapted to produce the 93% 

### < 200 mesh fineness assumed for these predictions. More full-scale testing would be required to fully evaluate this option. This is particularly true because the reagent utilization predictions using FGDPRISM are typically not as accurate as the S02 removal predictions.

4-8The economic analysis also showed that sodium formate additive should be costeffective for maintaining current S02 removal efficiency by allowing operation with fewer recycle pumps.

4-9

### APPENDIX A Detailed S0 2 

### Removal Data and Chemical Analyses Results for Baseline and Parametric Tests

A-1

### Tables A-1 and A-2 summarize the detailed test conditions and S0 2 

### removal efficiency results for the baseline and parametric tests, respectively. In 

### these tables, each "test" represents a period of operation at constant conditions, and each "run" represents an individual Method 6 traverse at the absorber outlet. The times were recorded at the beginning and end of each traverse. The "average slurry pH" is measured with a calibrated portable meter. A reading
was taken at the beginning and end of each traverse, and the average result is shown. In 

### most
cases (except Baseline Test 6), the portable meter agreed closely with the control room indicator. The "absorber flue gas velocity" was calculated from the outlet duct pitot traverse, adjusted to the scrubber cross sectional area. The number of operating recycle pumps is shown for each test. (The relationship between pump number and spray header location is shown on Figure 2-1.) "Slurry flow" is the total recycle slurry flow to the test module spray headers calculated using the average of three separate recycle pump flow measurements made for each pump during the baseline test period. The "UG" 

### for each test was calculated**u~ing** 

### this flow rate and the measured flue gas volume for each individual run.
In 

### Table A-2 for the parametric tests, the "on-site formate" concentration was determined by buffer capacity titration, and the "off-site formate" concentration was determined by ion chromatography. These results were in good agreement.

All S02 

### concentrations in Tables A-1 and A-2 are reported on a dry flue gas basis, which is the basis of the NYSEG inlet S0 2 

### analyzer data. The "on-line inlet S0 2 " 

### for each run is the average of inlet**r~adings** 

### recorded every five minutes during the outlet flue gas traverses.

Two values are shown for the absorber outlet Method 6 S02 

### concentrations. The first value is based on the on-site titration for sulfate in the H 2

### 0 2 

### impingers using the barium perchlorate titration procedure. The second value is based on the off-site ion chromatograph analyses for sulfate in both the isopropyl alcohol (IPA) and H 2

### 0 2 

### impingers. In 

### most cases, the IPA impinger sulfate is only a small fraction of the total and is attributed to S0 3 

### in the flue gas. However, occasionally, the IPA impingers contained more sulfate than could be accounted for by S0 3 • 

### Sulfate can be introduced to the IPA impinger as a result of water condensation and S0 2 

### A-2TableA-1 Actual Baseline Test Conditions and Results

7/19/94 I 0900-1040 5.66 9.1 1,2,3,5 I 41900 I 85 I 1567 I 185 I 215 I 86.3 I 1.99

1 I 2 I 7/19/94 I 1104-1159 5.62 9.1 1,2,3,5 I 41900 I 85 I 1570 I 214 I 212 I 86.5 I 2.00

1 I 3 I 7/19/94 I 1353-1423 5.60 8.9 1,2,3,5 41900 I 87 I 1548 I 209 I 213 I 86.2 I 1.98

4 I 7119/94 I 1444-1514 I 5.60 8.8 1,2,3,5 419oo 1 88 I 1532 I 212 I 222 I 85.5 I 1.93

;J> II 1 I 5 I 7119/94 I 1534-1617 I 5.64 9.1 1,2,3,5 419oo I 86 I 1453 I 195 I 210 I 85.6 I 1.94

I

(.;.) II • I 6 I 7/19/94 I 1635-1705 I 5.68 I 8.7 I 1,2,3,5 41900 I 85 I 1504 I 180 I 195 I 87.1 I 2.05

2 I 1 I 7/20/94 I 0943-1018 I 5.58 8.6 1,2,3,4,5 51900 111 1479 103 101 I 93.1 I 2.68

2 I 2 I 7/20/94 I 1040-1110 I 5.56 8.9 1,2,3,4,5 51900 108 1574 142 142 I 91.0 I 2.41

3 I 1 I 7/20/94 I 1403-1433 I 5.60 10.0 2,3,4 31900 59 1565 324 327 I 79.1 I 1.57

3 I 2 I 7/20/94 I 1452-1522 I 5.58 I 9.6 I 2,3,4 31900 62 1495 312 331 77.9 I 1.51

4 I 1 I 7/21194 I 0824-0854 I 5.03 I 9.3 I 2,3,4 31900 63 1800 572 567 68.5 I 1.15

4 I 2 I 7/21/94 I 0916-0947 I 5.00 I 9.4 I 2,3,4 31900 62 1808 582 571 68.4 I 1.15

5 I 1 I 7/21/94 I 1032-1103 I 5.l8 I 8.4 I 1.2.3.4,5 51900 113 1760 253 246 86.0 I 1.97

5 I 2 I 7/21/94 I 1121-1152 I 5.18 I 8.9 I 1,2,3,4,5 51900 107 1697 304 282 83.4 I 1.79

SA I 1 I 7121/94 I 1604-1632 I 4.94 9.4 1,2,3,5 41900 82 1697 408 442 74.0 I 1.35

6 I 1 I 7/22/94 I 0912-0939 I 5.65 3 9.4 2,3,4 I 31900 I 62 I 1683 I 195 I 202 I 88.0 I 2.12

6 I 2 I 7/22/94 I 0956-1023 I 5.64 3 9.2 2,3,4 I 31900 I 64 I 1700 I 193 I 195 I 88.5 I 2.167 I 1 I 7/22/94 I 1045-1112 I 5.81 I 8.5

7 I 2 I 7/22/94 I 1130-1157 I 5.82 I 8.4

8 I 1 I 7/23/94 I 0830-0857 I 5.60 I 6.2

> .. 8 I 2 I 7/23/94 I 0914-0941 I 5.60 I 6.3

.!.. a These pH readings are questionable. Table A-1 (Continued) 1,2,3,4,5 1,2,3,4,5 1,2,3,4,5 51900 1,2,3,4,5 51900 155 152 I 1315 I 51

I 1353 I 51 76 I 95.6 I 3.12

60 I 96.5 I 3.35

I 43 I 96.8 I 3.43

I 51 I 96.2 I 3.27TableA-2 Actual Parametric Test Conditions and Results

8/22/94 I 1640-1720 5.60 6.7 1,2,3,4 41600 113 530 1941 65 72 96.3 3.30

2 8/23/94 I 0950-1 o 19 5.74 7.4 1,2,3,4 41600 102 530 570 1430 29 37 97.4 3.66

3 8/23/94 I 1150-1218 5.60 7.9 1,2,3,4 41600 96 450 570 1361 39 63 95.4 3.08

4 8/23/94 I 1351-1418 5.58 8.8 1,2,3,4 41600 86 450 510 1531 51 52 96.6 3.39

5 8/23/94 I 1451-1521 5.60 8.8 1,2,3,4 41600 86 450 510 1553 52 58 96.3 3.29

6 8/23/94 I 1555-1622 5.63 6.3 1,2,3,4 41600 121 435 520 1603 28 31 98.1 3.96

**~** 7 8/23/94 I 1647-1714 5.63 6.1 1,2,3,4 41600 124 435 520 1567 37 41 97.4 3.65

2 8/24/94 I 0938-1005 5.60 9.0 1,2,3,4 41600 880 1272 25 25 98.1

VI 84 800 3.95

2 2 8/24/94 I 1026-1053 5.63 9.3 1,2,3,4 41600 82 700 880 1284 26 26 97.9 3.88

2 3 8/24/94 I 1445-1512 5.67 8.6 1,2,3,4 41600 88 1000 1080 1451 24 25 98.3 4.08

2 4 8/24/94 I 1535-1602 5.68 8.0 1,2,3,4 41600 95 1040 1080 1381 21 23 98.3 4.08

2 5 8/25/94 I 09ll-0939 5.67 8.6 1,2,3,4 41600 87 970 1060 1328 23 25 98.1 3.98

2 6 8/25/94 I 1005-1032 5.64 8.7 1,2,3,4 41600 86 970 1060 1340 25 26 98.0 3.93

3 8/25/94 I 1253-1321 5.61 7.6 1,2,3,4,5 51900 123 990 1070 1809 19 19 99.0 4.57

3 2 8125194 I 1347-1415 5.64 7.2 1,2,3,4,5 51900 130 990 1070 1789 17 16 99.1 4.72

4 8/25/94 I 1522-1539 5.59 8.0 2,3,4 31900 72 990 1090 1729 57 58 96.7 3.40

4 2 8/25/94 I 1610-1637 5.58 8.1 2,3,4 31900 71 990 1090 1738 61 63 96.4 3.32

5 8126/94 I 0818-0910 5.78 6.1 1,2,3,4,5 51900 154 950 1005 1587 II II 99.3 5.01

5 2 8/26/94 I 0929-1021 5.85 6.0 1,2,3,4,5 51900 156 950 1005 1654 14 14 99.2 4.80

6 8/26/94 I 1045-1113 5.87 7.7 2,3,4 31900 74 990 1010 1765 49 49 97.2 3.57

6 2 8/26/94 I 1133-1200 5.88 8.4 2,3,4 31900 68 990 1010 1844 45 45 97.6 3.727I1I8/26/94I1436-15057I2I8/26/94I1524-15518I1I8/26/94I1632-1700I8I2I8/26/94I1718-1745I9I1I8/29/94I0904-0954I928/29/941016-1107>I9 38/29/941130-1157I0\948/29/941219-12469I5I8/29/94I1517-15449I6I8/29/94I1604-163110III8/30/9410I2I8/30/942,3,42,3,45.20I8.5I1,2,3,4,55.201,2,3,4,55.521,2,3,45.567.61,2,3,45.588.01,2,3,45.567.91,2,3,41,2,3,41,2,3,41,2,3,4TableA·2(Continued)319007131900675190011051900114416001004160098416009441600954160092416008441600871877I151I152I91.9I2.521867I137I139I92.6I2.60I1000I1120I1878I65I65I96.6I3.37100066I66I96.4I3.34145025I26I98.4I4.161450I1520I1755I24I24I98.6I4.28145015101851I29I31I98.3I4.08145015101827I29I31I98.3I4.081450 152017134.091450152016874.11375038101508I8I9I99.4I5.10oxidation in the sample probe umbilical. The S0 2 concentrations in the "Off-site" column were corrected to include sulfate in the IPA impinger solution only if the amount in an individual sample greatly exceeded the average value for all of the samples. During the baseline tests, the only sample for which this correction was required was Test 1, Run 1. On the average, the onsite and off-site results agreed within about 1 percent. The reported "overall removal efficiency" for each run was calculated using the off-site results.

The final column in Tables A-1 and A-2 shows the number of transfer units ("NTU") calculated as In (S02ijS0 2

## ouJ for each test. The use of NTU in correlating the S0 2 removal data was discussed in Section 2.4.


### Solid Phase Analyses

Tables A-3 and A-4 show the solid-phase chemical analysis results for the baseline and parametric tests, respectively. The results are listed in chronological order. The sample description is based on the test number and run number designation used in Table A-1 for the S02 removal results. For example, sample B 1-1 is the first slurry sample from Baseline Test 1, Run 1, taken at the beginning of the first Method 6 traverse period. Sample 1-1,2 is the slurry sample taken in between the first and second Method 6 traverses, and sample El-2 is the slurry sample taken at the end of Test 1, Run 2.

Each $lurry sample indicated in the table was filtered, and the filter cake was dried and weighed to determine the slurry solids content in weight percent. A portion of the dried solids was then digested in O.lN HCl. The portion of solids that remained undissolved is reported as "inerts" in weight percent of the solids.

Also shown in the table are slurry density measurements recorded from the NYSEG operating logs ("NYSEG specific gravity"). These values were used to estimate the slurry solids content ("Estimated wt% Solids"), based on assumed values for the liquid- and solid-phase specific gravities. A-7TableA-3 Results of Baseline Test Solids Analyses

0910 1000 1150 1345 1435 1520 1610 1710 0940 1020 7 7.32 0.29 0.23 0.24 0.24

1.04 0.77 0.77 0.84 7.4 1.075 1 10.1 10.1 10.1 11.2 10.6 10.1 10.1 11.2 9.3 9.3 5.64 5.58 

### c NA NA 51.9 51.9
85.4 84.5 85.6 85.8 85.5 85.1 83.0 86.0 87.9 .86.8 86.2 85.1 85.9 86.1 85.3 85.2 83.2 86.0 87.9 86.9 1.0 81 86.3
1.18 1.17 1.21 1.15 1.18 1.17 1.20 1.15 1 1 1.16 3.5 4.0 3.6 4.1 wt% 81 0.0 0.0 0.0 0.0 11.5 11.3 13.1 9.9

.0 0.8 0.8 0.8 Closures

Weight,% -5.4 -2.1 -3.1 -5.0 Molar,% 2.1 -0.7 0.7 0.3 % 6.4 6.4 6.4 6.4

A-8Date 7/20/94 Time 1110 Ca,mm/g Mg,mm/g ISO,mm/g ITotal S (as SO,), mm/g 

### ISO,,mm/g !CO,,mm/g 0.90 Inerts, wt% Solids, wt% 6.0 ·NYSEGS.G. 1.07 '.., l wt'ff, Solids 9.3 

### IPH _5.53**~.** ,C Reagent Utility,%

Ca-Independent 87.9 S0 4 -Independent 88.2 ('{) T.**~-** Reagent Ratio

Ca-Independent S04 -Independent ("()_ 

# .. . 

## ... % Solid Solution, wt% 1Gypsumwt% 'CaCO,,wt% Inerts I

### ea. rrtf!!g 

### IMg. !Jlg/g SO,,mg/g Total S (as SO,), mg/g SO.,m!!/1!: CO,, mlifg Oosures

Weight,% Molar,% IJ. % 7120/94 7120194 1410 1442 7.46 0.20 6.29 6.57 0.28 1.15 1.03 0.89 9.4 7.8 1.075 1.075 10.1 10.1 _?.62**-~.59** 52.5
85.1 86.5 84.9 86.6**~8** 1.16 1.15 l.l7 4.3 85.3 0.0 10.3 0.9 298 5 293 631 27 62
-3.7 0.4 6.4 Table A-3 (Continued)

7120/94 7121/94

1530 0830

0.90 1.03

6.6 9.5 1.078 1.082 10.6 11.2**~6** _5.03

88.0 86.4 88.0 86.4

A-9 7121/94 7121/94 7121194 7121/94 7121/94 0900 0945 1040 1115 1150 7.36 7.40 7.47 0.27**_Q.~. ~2~**  6.28 6.41 6.49**_§.~4** 6.69 6.76 0.26 0.28 0.27 1.03 0.81 1.05 0.87 0.90 0.96 1.02 9.6 9.7 9.2 7.9 8.0 1.082 1.084 1.079 1.076 1.075 11.2 11.5 10.7 10.3 10.1 _5.03 _1.98 5.15 5.22 5.13 52.6 52.9 52.9
86.4 89.1 86.3 88.5 882 86.5 89.4 86.2 88.6 88.3 85.8 88.1 87.8
1.16 l.l3 1.13 1.16 1.13 1.13 1.17 l.l3 l.l4 4.0 4.2 4.1 84.8 86.8 87.7 0.0 0.0 0.0 10.3 8.7 9.0 0.0 1.0 1.0 294 296 299 7 5 6 502 513 519

. 628 642 649 25 27**-~6** 62 52 54
-5.1 -3.8 -2.5 0.4 0.2 0.2 6.4 6.5 6.5Date 7/21194 7122/94 7/22/94 Time 1610 0920 0950 Ca,mm/g 7.72 Mg,mm/g Q.23 SO,,mm/g 5.50 TotalS (as SO.), mm/g 5.70 SO.,mm/g 0.20 CO,,mm/g 0.69 2.51 2.24**~rts,wt%** 0.97 Solids, wt% 7.4 11.1 10.6 NYSEGS.G. 1.085 1.09 1.092 Estimated wt% Solids 11.6 12.3 12.6 pH 4.88 5.57 5.63 ,C 52.5 Reagent Utility,%

Ca-Independent 90.7 69.4 71.8 S0

4 -Independent" 91.0 68.5 71.9 rn· 71.7 Reagent Ratio Ca-lndependent 1.39 so.-Independent 1.39 ('0: 1.40 .% 3.5 Solid Solution, wt% 73.9 Gypsumwt% 0.0 CaCO,, wt% 22.3 Inerts 1.0

. Ca,mg/g 309 I Mg,mg/g 6 SO,, mg/g 440 Total S (as S04), mg/g 547 so.,mgtg 19 CO,,mg/g 134 Closures Weight,% -3.1 Molar,% 0.1

.... % 6.1 Table A-3 (Continued)

7122/94 7122/94

1035 1125 7.72 0.25 5.44 5.63 0.19 2.52 2.28 1.08 11.7 10.2 1.091 1.087 12.5 11.9 5.65 5.81 52.6
69.2 71.2 68.4 71.4 70.6
1.41 1.40 1.42 3.4 72.9 0.0 22.8 1.1 309 6 435 540 18 137
-3.3 0.4 6.1 A-10 7/22/94 7/23194 1200 0835

2.36 }.13

9.9 8.1 1.084 1.08 11.5 10.9 5.83 5.69

70.5 85.1 70.4 85.7 7123/94 7/23/94 NA 0900 9045 NA 7.62 9.05 0.28 0.37 6.28 6.46 0.18 1.18 1.07 9.14 1.03 1.62 9.1 8.2 NA 1.08 1.08 10.9 10.9 5.61 5_2) NA 52.3 NA
84.5 85.8 85.0 86.5 81.8
1.18 1.18 1.22 2.8 83.6 0.0 11.8 1.0 305 362 7 9

. 502 0

620 0 17 0 71 549
-2.9 -6.4 1.6 1.5 6.4 6.9

### TableA-4 Results of Parametric Test Solids Analyses

0950 1026 1133 1400 1435 1558 1624 0953 1015 1052 7.24 7.29 7.27 7

5.84 0.30 1.13 0.87 1.14 9.94 1.11 0.85 0.77 0.98 1.80 2.47

0.64 7.7 8.7 10.4 1.07 1.07 1.07 1.07 1.07 1.072 1.073 1.068 9.3 9.3 9.3 9.3 9.3 9.7 9.8 9.0 9.0 9.0
5.76 5.79 5.61 5.58 5.63 5.6

85.8 88.7 88.7 76.9 85.4 89.1 90.0 86.2 77.3 71.3 84.4 88.0 84.2 73.4 84.8 88.6 89.7 86.6 75.4 66.2 94.1 94.1 94.1 88.8 92.4 83.9

1.13 1.17 1.11 1.29 1.14 1.18 1.11 1.33 1.06 1.13 1.08 1. 4.8

0.0 8.7 18.0 Inerts 0.8 0.6 0.7 0.6 Closures

Weight,% -4.0 -5.5 -3.0 -4.2 Molar,% -3.0 -2.0 -1.3 -4.1 % 6.6 6.5 6.5 6.3



### A-ll1454 1520 7 0.36 6.03

0.35 1.69 1.43

79.1 81.7 77.8 81.2 83.8
1.22 1.23

0.0 14.3

9 482

0 33 86 Closures

Weight,% -3.6 Molar,% -1.3 % 6.2 1613

1.3

9.2 5.68

83.1 82.9 

### TableA-4 (Continued)

0920 0949

5.91

0.34 1.52 1.53

7.8 7.8 5.64 5.67 49.8
80.4 80.3 78.9 78.8

1.24 1.27 1.15

81.1 0.0 15.3 0.8

-5.1 -3.8 6.3 A-12 1037 1254 1342 1422 1608 7.18

6.13

0.8 0.61 0.98 1.82 1.12

10.2 1.06 1.077 7.8 7.8 7.8 7.8 10.4 5.64 5.67

88.6 91.4 86.9 78.2 85.5 8.9 91.5 86.3 74.6 85.2 90.8 87.5
1.15 1.17 1.16 1.17 1.10

84.7 0.0 0.0 9.8 11.2

490

59
-6.2 -3.5 -2.2 -1.1 6.5 6.31644 0831 0942

81.3 78.6 81.3 79.9 75.4 79.3 90.2
1.23 1.26 1 4.5

286

0 493

0 28

Closures

Weight, o/o -4.0 Molar, o/o -5.2 % 6.3 Table A-4 (Continued)

1030 1123

5.75

82.6 75.3 83.6 74.5 77.8
1.33 1.34

10 460

-3.3 -1.6 6.1 A-13 1208 14455 1523 1602 1712 7.12

6.09

78.2 81.7 81.5 88.3 90.6 78.3 79.8 79.6 88.1 90.4 1
1.23 1.10 1.26 1.11 1

525 0 0 31 31

-4.5 -3.9 -4.9 -1.4 6.3 6.51750 0908 1000

c
89.6 85.6 88.2 889.2 84.2 87.4 94.3
1.13 1.14 1

0.8 286 0

26

Oosures Weight,% -4.8 Molar,% -3.3 % 6.6 

### TableA-4 (Continued)

1114 1213

5.96

85.9 80.6 85.6 79.0 87.5
1.24 1.27 1.14

284 0 477

0

-6.2 -4.1 6.3 A-14 83.2 80.7 82.4 78.5 87.3 88.9 85.0 89.0 86.9 88.8 83.6 88.5 90.0 92.9
1.15 1.12 1.15 1.13 1 1.08

7 522 7 0 26 25 50
-4.6 -4.5 -1.5 -2.2 6.4 6.5The digested solids solution was analyzed for ca++ and Mg++ by atomic absorption and for S04 =by ion chromatography (IC). A separate portion of the dried solids was analyzed for SOt (sulfite) by thiosulfate/iodine titration. A third portion of the dried solids was analyzed for C0 3= (carbonate) by coulometric measurement of C02 gas evolved from an acidified sample. These analytical methods are described in detail in EPRI's FGD Chemistry and Analytical Methods Handbook.

Two calculated values for limestone utilization are reported in Tables A-3 and A-4 following the analytical results. Utilization is defined as [1 -moles of carbonate/(moles of product solids+ moles of carbonate)]. The "Ca-independent" value for utilization is calculated using the totalS (sulfite plus sulfate) analysis as the total moles of product. The "S0 4 - independent" value is calculated using the Ca analysis as the total moles of product + moles of carbonate. For samples with only carbonate analyses, approximate utilizations were calculated by using the calcium and sulfite/sulfate analyses for the closest sample from the same test that
was completely analyzed. The calculated utilization values are also expressed as reagent ratio, which is the inverse of utilization (expressed as a fraction rather than as a percentage).

Sulfite oxidation percentages reported in Tables A-3 and A-4 are calculated as 100
x [1 -moles of sulfite/moles of total sulfite plus sulfate].

The remaining entries in Tables A-3 and A-4 include solids analyses calculated on a weight basis, follo'o/ed by calculated "closures" for the analytical results. Closures are calculated as a quality assurance indicator. The molar closure in percent is calculated for a given set of solids analyses as the difference between the sums of positively and negatively charged ionic species in moles/gram divided by the total of the positively and negatively charged species in moles/gram (times 100). The calculated "acceptable" closure in percent is the expected error in the calculated molar closure at the 95% confidence level based on the assumptions that each of the individual analyses has a standard deviation of ±5% and that all significant species have been included in the analyses. The calculated closures in Tables A-3 and A-4 indicate good data quality for the solids analyses. All of the molar closures are well below the acceptable limits. A-15

### The calculated limestone utilization values in Table A-4 (plotted in Figure 2-6)
were scattered. This could be due to pH measurement, slurry sampling, or analytical problems. In order to check for analytical problems, six solid samples from Parametric Test 2, during which the slurry pH varied no more than ±0.05, were reanalyzed for carbonate. The results of these replicate analyses are shown in Table A-4 in parentheses below the original carbonate results. The analytical agreement was excellent, so the scatter in the utilization data is more likely related to slurry sampling problems.

Another discrepancy in the solid-phase analytical results for the parametric tests
can be seen by examining the slurry solids contents ("solids, wt%" in the tables). Material balance calculations show that, at full load, the maximum rate of increase in the slurry solids content in the test module reaction tank should be about 0.5 wt% per hour even if no slurry was bled from the tank. Inspection of**t~e** 

### parametric test data shows that the measured slurry solids content increased or decreased by as much as 3 or 4 percentage points in less than one hour.

There are two possible sampling problems that could account for these results. Either the slurry samples drawn from the sample tap were not representative of the hydroclone feed stream, or the tank was not well mixed at the location of the hydroclone feed pump suction. Because of this sampling problem, the NYSEG slurry specific gravity measurements have been used to estimate slurry solids contents when required for process calculations. 

### Liquid Analyses
Tables A-5 and A-6 show results of the liquid-phase analyses for the baseline and parametric test filtered slurry samples. Calcium, magnesium, and sodium were determined by atomic absorption spectrophotometry. Chloride, sulfite, sulfate, and thiosulfate were determined by ion chromatography. The reported result for "total hydrolyzable sulfate" is the total sulfate measured in the liquor sample after digestion under acidic oxidizing conditions, which converts all sulfur species to sulfate. The final result reported as "sulfur/nitrogen" species (SIN 

### in the

A-16Table A-5 Results of Baseline Test Liquid Analyses

1020 1442 0900 1115 0950 104 105 107 106 178 181 189 187 179

3.6 4.4 4.2 3.7 4.2 4.3 4.1 4.5 4.3 3.1 5. 5.74 2.32 2.01 1.99 2.91 1.90 2.58 2.66 0.62 0.59 0.59 1 2.09 2.02 2.15 2.05 2.21 2.20 2.31 2.34 2.40 23.0 23.3 22.5 20.1 24.3 23.2 26.9 20.3 18.9 21.2
11.2 11.2 10.9 7.1 12.5 9.3 12.7 9.8 11.2 10.4 5.64 5.60 51.9 51.9 52.5 52.6 52.9 52.5 52.6 52.3 4250 4180 41 4270 4240 3900 3750 4260 4340 4410 4580 4540 4350 4340 4330 1160 1240 1220 1160 1190 1160 20000 20700 20600 20000 20500

219 262 253 224 251 474 446 460 460 553 565 421 191 426 193 256 60 56 57 220 234 247 259 262 269 Charge Imbalance

Calculated, % 1.8 0.5 0.7 2.4 1.7 2.3 0.8 1.5 1.1 0.7 % 5.9 5.9 5.9 5.9 5.9 5.9 Relative Saturation

Gypsum 0.10 0.09 0.09 0.12 0.08 0.11 0.11 0.03 0.02 0.02 CaS0 3 *0.5H20 8.0 8.1 8.3 7.7 7.7 4.1 5.7 8.5 3.9 6.9 0.13 0.14 0.18 0.11 0.13 0.014 O.Q3 0.29 0.29 0.10

A-17

### Table A-6 Results of Parametric Test Liquid Analyses

1026 1435 1624 1015 1520 0949 1342 1608 0942 1123 47.2 48.6 47.9 48.6 48.1 47.0 45.9 45.4 42.3 42.3 216 211 73.9 75.6 481 479 490 4.41 4.70 4.04 4.66 3.96 4.94 4.07 4.36 4.20 4.10 3.23 3.30 11.34 9.77 9. 5.01 4.97 1.90 2.01 2.20 26.0 26.4 9.3 8.9 12.9 8.8 13.0 13.8 8.5 12.4 12.8 11.4 11.5 19.6 23.5 23.8 24.2 22.3 22.5 5.63 5.58 5.67 5.67 5.64 5.59 5.83 5.88 50.3 48.0 7 50.6 1920 1950 1930 1880 1840 1820 1690 1690 0 5130 0 0 1390 0 1700 0 0 1740 0 0 0 0 17100 0 17000 0 0 17400 0 0 278 294 265 282 68 325 222 316 323 373 317 395 326 349 336 328 258 264 810 1160 928 999 1090 938 900 821 481

0 0 212 0 225 0 0 246 0 0 1010 Ch¥ge Imbalance

Calculated, % 4.9 4.9 5.3 4.4 4.2 1.8 1.5 2.0 5.4 5.2 % 7.7 7.5 6.0 7.6 5.9 7.8 7.7 6.0 8.1 1 Relative Saturation

Gypsum 0.20 0.25 0.20 0.22 0.23 0.20 0.19 0.17 0.09 0.09 CaS03 *0.5H20 3.4 3.4 2.9 3.3 3.1 3.3 3.0 2.7 2.6 2.8 0.13 0.08 0.08 0.07 0.10 0.02 0.08 0.08 0.12 0.20
A-181523 1712 43.6 42.0 213

5.00 3.86 9.86 5.31 6.25 2.46 28.4 29.2 9.6 24.6 24.9 5.13 5.24 5 8 1750 1680

0 5190

0 16900 300 232 789 680 1 0 275 1110 1120 Charge Imbalance

Calculated, % 4.7 4.7 % Relative Saturation

Gypsum 0.10 0.11 CaS03 *0.5H20 3.0 3.0 CaC03 0.01 0.01 

### TableA-6 

### (Continued)

1000

. 4.86

5.19

29.3 17.3 33.8 5.48

1600

0

0 292 545

0 1520
2.7

0.09 3.4 0.04
A-19 1213

5.25

18 4.95

28.3 18.2 33.5 5.56

1550

315 415

0 1510
2.6

0.08 2.8 0.06 1554 1122 37.2 222 219

503 484

4.95 5.60 4.32 28.3 34.5

5.54 5.68

1550 1490

289 279 469 423

484 498 1520 3810
3.3 4.0 6.1
0.08 0.07 3.1 3.1 0.05 0.08

### TableA-7 Results of ICPES Analyses for Baseline and Parametric Test Liquids

ND ND ND ND ND ND ND ND 0.6 ND ND ND 0.3 0.1 0.1 0.1 ND ND ND ND Boron 640 560 540 550 Cadmium 0.008 ND 0.02 0.01 Calcium 4230 1860 1780 1470 Chromium <0.03 ND ND 0.01 Cobalt <0.03 0.01 0.04 0.01 <0.06 <0.04 <0.03 0.02 Iron 0.5 ND ND 0.6 Lead ND ND ND ND Lithium 0.8 0.8 0.8 0.8 4310 4750 4550 4760

0.9 0.3 0.4 0.3 <0.05 <.03 0.1 0.05 Nickel 0.9 0.7 0.7 0.7 Potassium 61 54 53 54 Selenium 0.6 <0.4 0.5 0.4 Silicon 7.7 6.1 5.6 7.1 Silver ND <0.02 ND ND Sodium 1140 1340 1590 1890 2.5 2.4 A-20Sulfur Thallium Tin Titanium

NA 

# = Not analyzed ND 

# = Not detected 1030 0.1 <0.09

ND 0.2 1.6 0.07 

### TableA-7 (Continued)

NA 0.2 <0.07

ND NA ND 0.02

A-21 NA NA ND ND ND ND ND ND NA NA ND ND 0.03 

### 0.04table) represents the difference between the total hydrolyzable sulfate and the sum of the moles of sulfur in the other individually reported sulfur species.

Calculated molar closures (charge imbalances) have again been used as a data quality check. All of the calculated charge balances are well within acceptable limits.

A-22

### APPENDIXB Detailed Formate Material Balance Data and Chemical Analyses Results for the Sodium Formate Consumption Test

B-1

### Table B-1 shows detailed sodium formate material balance data for the consumption test. During the three inventory days of the consumption test, formate concentrations were measured in most of the major system vessels. The actual liquid formate concentrations were measured for the reaction tanks, limestone slurry tanks, thickeners, and filtrate. The concentrations in the underflow storage tanks were assumed to be the same as that in the filtrate. The concentration in the supernate tank was taken as the average of the concentrations in the two limestone slurry tanks.

Each page of Table B-1 represents one consumption test inventory. For tanks that operate with variable levels, the level of each tank was also measured: The formate inventory in each system vessel is calculated in the rows at the top of each page. For example, the "B" module reaction tanks contained.l,OOO mg/L formate (as formate ion) on the first day (917/94). The total reaction tank volume was about 346,000 gallons. The estimated formate inventory in the liquid inventory for this module was 2,744lbs. The formate content of the solids in each tank


### was not measured, but was assumed to be the same as that measured in the filter cake solids. The amount of formate in the solid phase is much less than that in the liquid phase. The formate inventory change term in the material balance for a given test period was calculated as the difference in the total liquid-phase formate inventory at the beginning and end of the test period.

The total system liquid- and solid-phase formate inventory is shown at the bottom of columns 8 and 10. On the first 'day of the test, the liquid inventory was about 39,000**lbs~** 

### and the solid inventory was about 1,700 lbs (as formate ion). The next entry below the inventory estimate is the total inventory change since the previous day. This entry (as well as other entries below) is "0" for the first day.

The next group of three entries are the amounts of 40% sodium formate solution in the tanker in gallons and pounds and the calculated amount added since the previous test day. These amounts were determined by gauging the tanker. Note that the tanker was refilled with 45,500 lbs of sodium formate solution between the second and final inventories.



### B-2TableB-1DATE:9/07/94DetailedFormateMaterialBalanceDataTime:0700TankTank TankLiquidFormateFormateFormateMultiplierHeightHeightTankVol.FormateEstimatedinLiquidinSolidsinSolidsSamplelocation(gal/ft)(%)(ft)(gal)(mg/L)%Solids(1b)(%)(1b)------------------------------------------------------------------------------------------AMODULE144201002434608009.3D0.0000BMODULE1442010024346080100011.027440.074254CMODULE144201002434608010459.328910.074213'DMODULE144201002434608009.300.0000EMODULE144201002434608010907.630400.074173FMODULE144201002434608010459.328910.074213ATHICKENER13300010.513965008100.094320.0742BTHICKENER13300011.2148960011703.0143500.074283LSSLURRYSTORAGEA72006420.514745676535.07670.0000LSSLURRYSTORAGEB72009028.820736090535.012760.0000UNDERFLOWSTORAGEA64004213.083328108040.05860.074271UNDERFLOWSTORAGEB64005015.599200108040.06970.074322b:JSUPERNATETANK67909.5645058350.0449IFILTRATETANK170011.01870010800.0168wTOTALS5583129392911732TOTALLIQUID-PHASEFORMATEINVENTORYCHANGE0TANKERLEVEL(GAL)599940%SODIUMFORMATEINTANKER(LBS)6396440%SODIUMFORMATEADDEOSINCELASTINVENTORY(LBS)0LIMESTONEUSEDSINCELASTINVENTORY(TONS)0ASSUMEDAVERAGEUTILIZATION(%)90TONSS02REMOVEDSINCELASTINVENTORY(BASEDONLIMESTONE)0TONSS02REMOVEDSINCELASTINVENTORY(BASEDONCEM)0FILTERCAKEPRODUCEDSINCELASTINVENTORY(TONS)0AVERAGECAKESOLIDSCONTENT(%)76FORMATELOSTWITHCAKELIQUIDSINCELASTINVENTORY(LBS)0FORMATELOSTWITHCAKESOLIDSSINCELASTINVENTORY(LBS)0FORMATESOLUTIONLOSS(LB/TONS02)0FORMATENONSOLUTIONLOSS(LB/TONS02)0TOTALFORMATECONSUMPTION(LB/TONS02)0TOTALSODIUMFORMATECONSUMPTION(LB/TON502)0TableB-1DATE:9/09/94(Continued)Time:0710TankTankTankActualLiquidFormateFormateFormateMultiplierHeightHeightTankVol.·FormateEstimatedinLiquidinSolidsinSolidsSamplelodation(gal/ft)(%)(ft)(gal)(mg/L)%Solids( 1b)(%)( 1b)------------------------------------------------------------ ------------------------------------AMODULE144201002434608009.300.0000BMODULE1442010024346080105015.128200.076367CMODULE1442010024346080114012.930970.076310DMODULE144201002434608009.300.0000EMODULE1442010024346080108011.229610.076265FMODULE1442010024346080120018.331650.076454ATHICKENER13300010.513965007100.082670.0762BTHICKENER13300011.2148960013003.0159450.076291LSSLURRYSTORAGEA72009028.820736097035.013670.0000LSSLURRYSTORAGEB72006420.514745699035.09920.0000UNDERFLOWSTORAGEA64005517.1109120110040.07810.076364UNDERFLOWSTORAGEB64006219.2123008110040.08810.076410t:rJSUPERNATETANK67909.5645059800.0527FILTRATETANK170011.01870011000.0172TOTALS5632729409752464TOTALLIQUID-PHASEFORMATEINVENTORYCHANGESINCE9/7(LBS)1684TANKERLEVEL(GAL)410340%SODIUMFORMATEINTANKER(LBS)4374840%SODIUMFORMATEADDEDSINCELASTINVENTORY(LBS)20216LIMESTONEUSEDSINCE9/7INVENTORY(TONS)815ASSUMEDAVERAGEUTILIZATION(%)90TONSS02REMOVEDSINCE9/7INVENTORY(BASEDONLIMESTONE)427TONS502REMOVEDSINCE9/7INVENTORY(BASEDONCEM)522FILTERCAKEPRODUCEDSINCE9/7INVENTORY(TONS)1316AVERAGECAKESOLIDSCONTENT(%)76FORMATELOSTWITHCAKELIQUIDSINCELASTINVENTORY(LBS)697FORMATELOSTWITHCAKESOLIDSSINCELASTINVENTORY(LBS)1494FORMATESOLUTIONLOSS(LB/TONS02)1.3FORMATENONSOLUTIONLOSS(L8/TONS02)5.7TOTALFORMATECONSUMPTION(LB/TONS02)7.0TOTALSODIUMFORMATECONSUMPTION(LB/TONS02)10.6TableB-1DATE:9/12/94(Continued)Time:071DTankTank TankActualLiquidFormateFormateFormateMultiplierHeightHeightTankVol.FormateEstimatedinLiquidinSolidsinSolidsSamplelocation(gal/ft)(%)(ft)(gal)(mg/L)%Solids(1b)(%)( 1b)------------------------------------------------------------------------------------------------AMODULE144201002434608009.300.0000BMODULE1442010024346080104512.928390.089363CMODULE1442010024346080110015.229520.089434DMODULE1442010D2434608009.300.0000EMODULE144201002434608010709.829530.089270FMODULE1442010024346080125014.433700.089407ATHICKENER13300010.513965008500.098970.0893BTHICKENER13300011.214896009003.0110390.089341LSSLURRYSTORAGEA72007022.416128099035.010850.0000LSSLURRYSTORAGEB72009129.120966499035.014110.0000UNDERFLOWSTORAGEA64005115.8101184110040.07250.089395UNDERFLOWSTORAGEB640D6319.5124992llOO40.08950.089488o;SUPERNATETANK67909.5645059900.0532IFILTRATETANK170011.01870011000.0172VITOTALS5642905378702702TOTALLIQUID-PHASEFORMATEINVENTORYCHANGESINCE9/9(LBS)-3105TANKERLEVEL(GAL)553440%SODIUMFORMATEINTANKER(LBS)5900640%SODIUMFORMATEADDEDSINCELASTINVENTORY(LBS)30322LIMESTONEUSEDSINCE9/9INVENTORY(TONS)1525ASSUMEDAVERAGEUTILIZATION(%)90TONSS02REMOVEDSINCE9/9INVENTORY(BASEDONLS)799TONSS02REMOVEDSINCE9/9INVENTORY(BASEDONCEM)824CAKEPRODUCEDSINCE9/9INVENTORY(TONS)2007AVERAGECAKESOLIDSCONTENT(%)77FORMATELOSTWITHCAKELIQUIDSINCELASTINVENTORY(LBS)1007FORMATELOSTWITHCAKESOLIDSSINCELASTINVENTORY(LBS)2557FORMATESOLUTIONLOSS(LB/TONS02)1.2FORMATENONSOLUTIONLOSS(LB/TONS02)12.3TOTALFORMATECONSUMPTION(LB/TONS02)13.5TOTALSODIUMFORMATECONSUMPTION(LB/TONS02)20.4

### The next group of entries includes data used to estimate the total tons of S0 2 

### removal for each test day. Daily limestone weigh belt readings and differences in limestone slurry tank levels from day to day were used for one estimate of S0 2 

### removal. The solids content of the limestone slurry and the average utilization had to be assumed for this calculation. This result is shown as "tons S0 2 

### removed since last inventory (based on LS)." The next line, "tons S0 2 

### removed since last inventory (based on CEM)," was estimated using the average unit load, unit heat rate, and inlet and outlet CEM data in lbs of S0 2 

### per million Btu heat input. This value is expected to be more accurate than the value estimated from limestone consumption.

The next group of entries estimate the amount of formate leaving the system with the filter cake. The amount of filter cake produced since the last inventory was provided by NYSEG from weigh belt readings. The solids content of the filter cake was measured. The formate concentration in the filter cake liquid was assumed to be the same as that of the filtrate, which was measured.

On the second and third pages of Table B-1, the concentrations of formate in each vessel are shown for the second and third inventory days, and the calculated quantities appear as described above. The final four entries show the calculated solution and nonsolution loss rates and the total formate and sodium formate consumption rates since the previous inventory. The overall average consumption results shown in Table 2-3 were calculated for the period between the first and final inventories. Slurry samples were obtained from each of the operating modules during the consumption test. Results of the solid- and liquid-phase analyses are shown in Tables B-2 and B-3. In 

### these tables, the sample designation "B-917", for example, refers to the slurry sample from the B Module taken during the 917/94 inventory. The remainder of the tables have the same format as those presented for the baseline and parametric test slurry analyses. The molar closure results for the long-term solid and liquid analyses indicate good data quality for all of the samples except solid C-9/12. The calcium analysis for this sample appears to be 

### low.



### B-6TableB-2 Results of Consumption Test S,Olids Analyses

0758 0744 0810 0756

7.18 7.21 7.22 6.15 0.30 0.19 0.36 0.12 6.58 6.53 6.66 6.23 6.72 6.77 6.68 6.85 6.37 7.08 6.93 0.16 0.21 0.60 0.74 0.80 0.96 1.00 1.04 5.3 9.2 10.8 1.059



### c 50.1 51.1 51.1
87.5 86.7 88.7 80.8 92.2 90.4 91.6 84.7 88.1 88.0 87.2 86.4 88.2 80.1 90.4 90.0 91.3 84.3 87.7 87.5 89.3 89.3 84.1 113 93.5 95.1 87.2 90.7 91.6
1.14 1.15 1.13 1.24 1.08 1.11 1.09 1.18 1.14 1.14 1.15 1.16 1.13 1.25 1.11 1.11 1.10 1.19 1.14 1.14 1.12 1.12 1.08 1.19 0.88 1.07 1.05 1.15 1.10 1.09

wt% 0.0 9.2 0.9 289 7 508 650 641 658 665 673 627 651 648

18 14 19 20 20 18 14 14 52 44 71 55 55 Closures

Weight,% -3.0 -3.9 -3.4 -3.6 -7.4 -3.2 -3.3 -3.9 -3.5 -4.4 Molar,% -1.0 -1.4 -2.1 -2.0 -10.2 -1.7 -1.9 01.4 -1.5 -2.0 Acceptable, % 6.5 6.4 6.5 6.3 6.7 6.6 6.6 6.4 6.5 6.5 

### B-7TableB-3 Results of Consumption Test Liquids Analyses

0824 0810 32.3 31.2 226.5 84.4 89.4 90.9 107.4 91.0 85.6 86.7 87.2 94.4 470.6 495.3 498.0 532.3 510.2 482.0 491.7 479.7 537.8

6.4 5.3 7.2 6.0 7.0 5.9 5.5 7.4 4.7 4.4 6.2 4.6 5.7 5.6 5.3 6.8 3.4 3.2 3.9 2.9 3.3 4.5 4.0 3.7

422 356 332 446 457 451 421 541 315 431 381 351 279 764 796 1071 1202
2.7 2.9 1.3 2.4 % 6.1 6.1 6.1 6.1 Relative Saturation

Gypsum 0.05 0.04 0.05 0.04 0.04 0.06 0.05 0.05 0.04 0.03 CaS0 3 *0.5H20 2.5 2.4 2.5 2.5 2.6 3.1 2.4 3.3 2.3 2.2 0.09 0.08 0.05 0.09 O.Q7 0.10 0.05 0.08 0.08 0.12
B-8

### APPENDIXC Other Process Data

C-1<ltSTableC-1OtherProcessDatafortheBaselineandParametricTestsB-8 2 7/23/94 I 0914-0941 709 3.0

Inlet 8/22/94 I 0950-1010 690 3.0

Inlet 8122/94 I 1036-1056 694 2.9

Inlet 8/22/94 I ll14-ll34 699 3.0

("') P-1 8/22/94 I 1640-1720 690 3.0

I w P-1 2 8/23/94 I 0950-1019 406 6.4

P-1 3 8/23/94 I 1150-1218 386 6.6

P-1 4 8/23/94 I 1351-1418 477 5.6

P-1 5 8/23/94 I 1451-1521 489 5.5

P-1 6 8/23/94 I 1555-1622 510 5.0

P-1 7 8/23/94 I 1647-1714 502 5.3

P-2 8/24/94 I 0938-1005 282 6.8

P-2 2 8/24/94 I 1026-1053 290 6.7

P-2 3 8/24/94 I 1445-1512 424 6.4

P-2 4 8/24/94 I 1535-1602 382 6.5

P-2 5 8/25/94 I 1911-0939 398 6.3

P-2 6 8/25/94 I 1005-1032 432 6.0

P-3 8125194 I 1253-1321 670 3.0

P-3 2 8/25/94 I 1347-1415 674 3.1 6.6 5
6.8 4
6.7 4
6.8 4
6.7 4
9.9 3 10.1 3
9.1 3
9.0 3
8.4 4
8.8 4 10.3 2 10.2 2
9.6 3
9.6 3
9.5 3 9.0 3
6.5 4 6.6 4 Table C-1 (Continued)
1320 3.23 1876 4.50 1875 4.51 1905 4.54 1941 4.65 1430 4.28 1361 4.26 1531 4.40 1553 4.39 1603 4.42 1567 4.38 1272 4.04 1284 4.07 1451 4.20 1381 4.11 1328 3.97 1340 4.10 1809 4.22 1789 4.20 0.51 12.1 12.7 515 4.2 0.8 2.0

0.55 11.5 126 524 5.0 -6 N/A

0.56 11.6 126 525 4.9 2 N/A

0.57 11.7 127 523 5.0 2 N/A

0.55 11.7 127 522 5.0 2 N/A

0.54 8.8 129 430 4.0 22 N/A

0.55 8.6 130 434 4.1 23 N/A

0.57 9.5 128 454 4.9 15 N/A

0.58 9.6 128 470 5.0 15 NIA

0.49 9.9 127 3.6 15 NIA

0.54 9.8 128 464 3.7 20 NIA

0.54 8.4 128 283 4.4 22 NIA

0.57 8.4 131 303 5.4 22 N/A

0.95 124 333 4.6 22 N/A

0.26 8.5 123 351 4.9 -3 N/A

123 328 4.4 -6 NIA

124 363 5.0 2 NIA

127 481 5.0 -6 NIA

127 477 4.8 -6 N/A(1,!:,.P-48/25/94I1522-15396733.07.1P-428/25/94I1610-16376823.0P-58/26/94I0818-091o5354.78.0P-528/26/94I0929-10215714.47.9P-68/26/94I1045-11136433.37.0P-628/26/94I1133-12006803.06.6P-78/26/94I1436-15056653.06.7P-728/26/94I1524-15516703.06.5P-88126194I1632-17006813.06.5P-828/26/94I1718-17456953.06.5P-98/29/94I0904-09545744.28.0P-928/29/94I1016-11076153.87.2P-938/29/94I1130-11576553.26.9P-948/29/94I1219-12466463.26.9P-958/29/94I1517-15445554.78.1P-968/29/94I1604-16315524.78.1P-108/30/94I0948-11083736.59.828/30/948(I)Boiler%02isaverageofeastandwestmonitors.(2)IDfanmotorcurrentissumofampsonfanslA,IB,and1C.(3)BypassdamperApositionisshown;otherbypassdampersareclosed.444444444444444433TableC-1(Continued)17294.23173815874.3316544.3817654.4318444.4018774.4018674.4118784.3818684.3916774.3617554.3618514.4318274.4817134.4716874.5115084.590.3011.51275434.9-6N/A0.4811.51275224.6-6N/A0.569.91284983.514N/A0.5710.51283883.714N/A0.5811.41274384.314N/A0.5811.51294814.615N/A0.4611.21304834.712N/A0.4811.31304924.9-6N/A0.5111.31294965.3-5N/A0.4011.41295165.23N/A0.3110.51233934.06N/A0.3610.91264624.515N/A0.3711.31274504.615N/A0.3911.31274554.616N/A0.2510.01234194.9-6N/A0.2310.01234194.9-6N/A0.288.71223204.10N/A0.288.71203164.0N/ATableC-2OtherProcessDatafortheSodiumFormateConsumptionTesta9171945734.27.73.690.4810.6I129I440I3.7I249191946623.16.94.020.5011.3I130I472I3.8I20n9110/946673.16.93.960.4311.4129467I3.8I21IVI9/111946273.67.44.460.5410.9128450I3.8I199/12/946523.37.04.420.5411.1128453I3.8I19aDatarepresentaverageconditionsfortheprevious24-hourperiodasof0700oneachday.bStackS02includespartialbypass.

### APPENDIXD FGDPRISM Calibration

D-1The FGDPRISM calibration involves an iterative process in which the parameters
are adjusted to obtain the best overall fit to the performance data. The steps used in the Kintigh FGDPRISM calibration procedure are summarized below:

1. Test results were reviewed to select data sets representative of each baseline and parametric test. Each test had two or more runs that provided S02 performance data and samples for laboratory analysis. Baseline Tests 2 and 5, and Parametric Test 10, were selected for use in the calibration. The intent was to select tests with similar gas velocities but a wide range of S0 2 removal efficiency. 2. Liquid-phase analyses from the selected tests**w~re** input into the FGDPRISM equilibrium module to determine partial pressure of C0 2 and relative saturations of CaC0 3 , CaS0 3 •Yili20, CaS0 4 •Y2H20, and CaS0 4•2H2 0. 3. The FGDPRISM material balance module was run for each calibration case, and the following inputs were adjusted to best match the flue gas, liquid, and solid compositions:

• Unit load (gas velocity); • Coal percent sulfur (FGD inlet S0 2 concentration); • Reagent ratio (LS utilization and slurry pH); • CaS0 3 RS multiplier (RS of CaS0 3 •Yili20); • Percent oxidation (S04 in liquid and solid); • Coal chloride content (Cl in liquid); • Limestone MgC0 3 solubility (Mg in liquid); • Makeup water sodium content (Na in liquid); and • Makeup water magnesium content (Mg in liquid). 

### 4. 'Using the FGDPRISM complete system simulation, adjustments were made to the following FGDPRISM system simulation inputs to obtain the best fit to the three calibration cases:

• Gas-film thickness; • Liquid-film thickness; • Limestone reaction rate constant; • Limestone surface area factor; and • Solid solution rate constant. Reagent ratio was also input and adjusted for each of the cases during this calibration.
D-2

### 5. The system simulation model was then run with data from the other baseline tests. However, S0 2 

### removal results did not match the observed results because of differences in gas velocity. Iterative runs were then made for each case by adjusting the reagent ratio to achieve desired pH levels and then changing the gas-film thickness to reach the desired S0 2 

### removal. The revised gas-film thickness results are shown in Figure D-1, with a straight line determined by regression analysis. The equation for the line is: Gas-film thickness (f.l) 

# = -2.016 *(Gas velocity, ft/s) 

### + 22 

### 6. All of the baseline and parametric test cases were then simulated using the gas-film thickness determined by the above equation.
The final calibration parameters were: Input Gas-film thickness, microns (at 9ft/sec) Liquid-film thickness,% of droplet diameter Reaction rate constant Surface area factor Solid solution rate constant Value 

### 4.0 0.06 1.6e-5 1.0 3.0e-8

Table D-1 compares predicted and observed results for the calibration cases and the remaining tests. The results of the calibration were very good with respect to agreement between predicted and observed S0 2 

### removal efficiency. The only case for which the predicted S02 

### removal was substantially different than the actual removal was Baseline Test 4 (58.7% predicted vs. 68.5% actual S02 

### removal). This particular data point lies well outside the range of interest for this project, though. For the remaining 17 cases, the average predicted S02 

### removal efficiency was less than 0.1 percentage points higher than the average observed removal with a standard deviation of only 1.1 

## so2 removal efficiency percentage points.

The agreement between predicted and observed pH and limestone utilization, especially for the low-pH tests, was not as good as that for S0 2 

### removal. To match the observed
D-3**lOr-------------------------------------------~**



### 8



# - 1:1'.) 

# =**~** a. u 

# ... e 6 

# - fl:l fl:l**~** 

## Ja u 

# ... .c Eo.; 

## a 4 

# - ...**~** fl:l Para 10 

# = c 2 

### 3.
0 

### 6 7 8 9 

### 10 

### Gas Velocity (ft/sec)

Figure D-1. Kintigh FGDPRISM Calibration: Gas Film Correction

D-4B-1 8.9 B-2* 8.8 B-3 9.8 B-4 9.3 B-5* 8.6 B-6 9.3 B-7 8.5 B-8 6.2 P-1 6.2 P-2 8.3 P-3 7.4 P-4 8.1 P-5 6.1 P-6 8.1 P-7 8.4 P-8 8.4 P-9 8.5 P-10* 8.6 TableD-1 FGDPRISM Calibration Results Comparison of Observed and Predicted Performance

4.05 5.54 5.60 84.0 85.3 4.25 5.50 5.58 86.4 86.8 2.23 5.55 5.59 84.1 86.6 3.24 5.28 5.02 91.8 86.5 4.65 5.28 5.18 90.0 88.5 3.24 5.77 5.80 63.1 71.9 4.85 5.75 5.81 63.2 71.4 9.49 5.64 5.61 86.2 85.0 9.49 5.61 5.63 89.3 89.7 5.25 5.68 5.67 83.7 81.2 7.07 5.62 5.64 86.3 86.3 5.66 5.56 5.59 85.2 85.2 9.69 5.86 5.83 79.8 79.3 5.66 5.84 5.88 62.9 74.5 5.05 5.12 5.13 94.0 79.6 5.05 5.21 5.24 94.2 90.4 4.85 5.49 5.54 88.9 86.9 3.24 5.63 87.7 

## * These tests used in calibration.



### D-5 88.1 85.9 93.8 92.0 76.2 78.5 58.7 68.5 84.1 84.7 88.7 88.2 96.4 96.0 96.3 96.5 96.3 98.0 98.6 98.5 98.5 99.1 96.8 96.6 98.3 99.2 96.5 97.4 93.5 92.3 98.0 96.6 98.4 98.4 99.9 99.5

### pH for the low-pH tests (Baseline Tests 4 and 

### 5, Parametric Tests 7 and 8), FGDPRISM required that significantly higher limestone utilization be used as input than was actually measured in three of the four cases. Conversely, to match the tests at high pH (Baseline Tests 6 and 7, Parametric Tests 5 and 6), FGDPRISM required significantly lower utilization as input than was actually observed in three of the four cases.



### D-6

### APPENDIXE Detailed Economic Calculations

E-1

### Table E-1 includes more detail with respect to the added costs of S02 

### removal for the cases shown in Table 4-2. Table E-1 also includes costs for additional options that were less cost-effective than those shown in Table 4-2.

E-2Table E-1 Economic Comparison of S0 2 Removal Upgrade Options

5.6 0 85 85.0 0 0 0 0 o I

5.6 0 85 88.0 2500 0 0 28000 57000

trlll Close bypass I 5.8 0 85 96.8 9840 0 0 28000 326000'

W (4pumps) Use **finer~** I 5.61 1000 I 851 97.81

Close bypass 10640 I 55000 I 30tooo I 28000 I I 245000 I

(4 pumps)

formate

I 5.6 I 1250 I 85 I 96.7 I 9730 I 57000 I 372000 I 19000 I -152000 I 224000 I

5.6 1000 85 94.8 8140 55000 292000 187000

5.2 1250 89 95.4 8680 57000 367000 I 28000 117000

5.8 750 72 97.9 10770 53000 226000 I 28000 586000 o I 0 43000 128000 167000 521000 181000 I 810000 I 165000 I 685000 I 138000 I 672000 143000 I 712000 199ooo 1 1092o0 0 51 500 250

53 1940 960

76 I 1850 I 790

10 I 1750 I 770

83 1360 550

82 1460 590

101 1600 520t.r1.!..MaintaincurrentS02removal,Finergrind(4pumps)5.509885.00TableE-1(Continued)0aIncreasedreagentcostincludes$100,000/yearforincreasedreagentpreparationO&M.00-116000"I-108000I-224000