# Date: October 21, 2011
To: Docket ID No. EPA-HQ-OAR-2007-0011

From: Kristin Sroka Subject: NSPS Subpart J Review: Meeting Minutes for February 25, 2011, Conference Call Between the U.S. EPA and Representatives of Lion Oil and John Zink

Introduction
On February 25, 2011, representatives of the U.S. Environmental Protection Agency (EPA) and their contractor (RTI International) participated in a conference call with representatives of Lion Oil Company (Lion Oil)and John Zink Company LLC (John Zink). This conference call was a follow-up to the conf erence call on July 16, 2009. The names and affiliations of the participants are included in Attachment 1. Attachments 2 and 3 contain the background information provided by the Lion Oil representatives prior tothe conference call; Attachment 2 is detailed information regarding flare sampling and Attachment 3 shows facility flare information from 2005 and 2006. The purpose of the conference call was to discuss the requirements for monitoring flares with flare gas recovery systems in NSPS subpart Ja.

Discussion
The discussion mainly centered around the flaring information provided in Attachment 3. The EPA representatives were concerned that the data did not explain whether flaring instances were caused by brief events or large events. The Lion Oil representatives noted that, in general, anything that lasted over 2 minutes was a large event that exceeded the three compressors, while anything less than 2 minutes could be due toeither compressor staging or an event.
The Lion Oil representatives stated that the data show flaring from two flares, one that handles low-pressure releases and another that handleshigh-pressure releases (designed based on the pressure at which each unit releases). Eachflare has three compressors, and the capacity of each compressor is 700 standard cubic feet per minute (scfm). Most of the releases with higher concentrations of sulfur dioxide (SO2

# ) were from the low-pressure flare, which tends to receive discharges from the units with more sulfur. The discharges to the high-pressure flares are mostly hydrogen from hydrotreaters.
One EPA representative said that when looking at the data from Lion Oil and backcalculating H2

# S from SO2

# for events that lasted 1 minute or less (which, according to Lion Oil, could be either staging or capacity exceedances), there were no exceedances of the subpart J H2

# S

# 2

concentration limit for fuel gas combustion devices. He could not be certain because the company did not provide direct H2

# S concentration data, but based on the data provided, he did not think Lion Oil would have problems meeting subpart J or subpart Ja. The Lion Oil representatives agreed that releases from the high-pressure flare are not as much of a concern because of the low sulfur content of the discharges from the units. However, a discharge to the low-pressure flare can have an H2

# S content of 5 percent, and a discharge as short as 1 minute at that concentration could cause an exceedance of the 3-hour concentration requirement for the flare. The EPA representatives noted that they could consider a paradigm in which they would use their enforcement discretion in making decisions about whether discharges due to compressor staging are actually violations of the H2

# S concentration requirements in subpart Ja (rather than including a specific exception for compressor staging).
The Lion Oil representatives stated that another problematic issue is a system with small capacitance (small diameter and linear header). Lion Oil put theirwater seal inside the stack. The EPA representatives asked the John Zink representative if that conf iguration is common, as well as whether the system would be improved ifa larger seal were placed outside the stack.
The John Zink representatives replied that every application isdifferent. In this case, they looked at the system as itwas being designed and agreed that a 30-inch seal would provide operational flexibility. The decision to retrofit the existing liquid seals was the best option at the time. When designing flare gas recovery systems, if the flare does not already have a liquid seal, John Zink will design a new one from scratch. If onealready exists, John Zink tries to use or modify the seal to thebest extent possible.
The John Zink representatives stated that a 30-inch seal was determined to be more than adequate for normal operations of the two flares atLion Oil. They noted that there is no real performance difference between 30- and 40-inch seals. The only gain with a deeper seal is a slightly larger band for the setpoint at which the next compressor is set to start up. A 30-inch seal is standard and gives a 15-inch buffer (7.5 inches at the top and 7.5 inches at the bottom) to keep compressors from going on and off continuously, burning out motors.
The John Zink representatives noted that the pressure is monitored in the flare header itself, preferably between the knockout and thetake-off point of the flare gas recovery unit (alternatively, sometimes in the take-off point). The pressure monitors in Lion Oil’s system are located between the knockout and the take-off point.The John Zink representatives stated that the closer the pressure monitor is to the mainflare header, the more time there is for the compressors to cycle. The EPA representatives asked whether monitoring the pressure before the knockout drum would be better since that is even further from the compressors. The John Zink representatives responded that some time would be gained, butit is only fractions of a second because only a very small amount of compression occurs.
The John Zink representatives noted that the system should be set up to avoid a pressure drop between the compressors and the flare header.Once in the flare header, the pressure is not much different, and slight variations throughout the system could give a false reading. If the false reading is too far off, air could be drawn into the flare.

# 3

The John Zink representatives stated that for a 30-inch seal, 15 inches is a typical set point. The John Zink representatives stated that they typically design their systems to turn on the second compressor if the pressurereaches 7.5 inches above the set point, or 22.5 inches. Lion Oil shortened the band on their system so thatthe second compressor turns on at 20 inches, to try to get better control of events.
The John Zink representatives stated that the 10-30 second delay in startup of the compressor motors is typical of the design becausethey are large motors. Once they shut down, a certain amount of time must pass before they can be restarted. An energy management system could be installed so that the second motor runsfor a minimum of 15 minutes, but then if the event is less than 1 minute, a lot of energy is expended energy just to recycle gas through the system, as no gases are being recovered during that time. There is also an issue with spill back valve capacity. If allthree compressors are running and no gas is being recovered, the pressure drops so much that it becomes diff icult to operate the system. Onthe other hand, if the spill back valve is designed to handle all three compressorsrunning more often, much of the system control is lost, and there is trouble sticking to the pressure set point.
The John Zink representatives stated that alltheir systems are custom, but the system at Lion Oil could be considered as “standard” asany of their systems today, even though it was installed 10 years ago. The John Zink representatives noted that it was one of the first multicompressor systems installed, and they often take prospective clients to see it. They also stated that the number of compressors for a system depends on the size of the flare, so there is not really a “typical” number of compressors. The John Zink representatives noted that they have not heard of many systems flaring between compressor staging like Lion Oil’s system. However, they clarified that they do not get a lot of feedback once the systems are in place, so while they can understand the conditions under which flaring between compressor staging would occur, they do not know for sure how common these types of staging issues are. They did note that they have heard of at least one other plant with the same experience as Lion Oil.

# Attachment 1 Participants in February 25, 2011 Conference Call

Industry Representatives Brian Blackwell, John Zink Ray Callahan, Ergon Scott Fox, John Zink Jim Franklin, John Zink George Garten, Lion Oil Company Chuck Hammock, Lion Oil Company
U.S. EPA Representatives Brenda Shine (OAQPS) Pat Foley (OECA)
RTI International (EPA contractor) Jeff Coburn Kristin Sroka

# Lion Oil Company ("Lion Oil") has installed flare gas recovery units ("FGRU's") on the two flare systems at its refinery in EI Dorado, Arkansas. The FGRU's at Lion Oil are adequately sized and have not one but two back up compressors in parallel for each flare. The seal for each flare system consists of a 30 inch water seal which is located at the base of each flare stack. (See Figure 1A)

The FGRU withdraws gas from the flare header upstream of the liquid seal drum and recovers gas that would normally be burned in the flare. The recovery system operates to maintain a slight positive pressure on the flare header upstream of the liquid seal drum, which ensures that air is not drawn into the flare system or the FGRU. When gas is relieved to the flare system, the compressors automatically stage up to handle the increase in volume to the flare system. This process is not instantaneous and Lion Oil often experiences small flaring releases, even though the control system is a state-of-art design. There are other process unit startups, shutdowns and malfunctions that also result in these micro flaring events.

The above mentioned water seal is monitored on a continuous basis and when the water seal is broken, which indicates a flaring event is occurring a signal is sent to the sample collection system to begin the sampling sequence. There is a delay in the sample collection in order to make sure the horizontal flare line has been purged, which allows for collection of a representative sample. After completion of the delay a solenoid opens allowing the flare gas sample pump to fill the sample canister with a gas sample from the horizontal flare line.

When the water seal is broken, an automatic email is sent to Lab personnel, Operations personnel and the Environmental department. The lab personnel then collect and analyze the flare gas sample via GC and provide the results to the Environmental Department for emissions quantification. The sample gathering and analysis takes about 1 hour.

The emissions are quantified using the flare gas analysis and the monitored flow during the flaring event. The flow is measured using a Panametrics measurement system that corrects for temperature, pressure and also measures molecular weight.

The flare gas sample collection system consists of a sample pump, heated sample line, in-line filter, solenoids and sample canister. The sample system currently utilized was designed in house at a cost of approximately $5000-10,000 (See Figure 1 B). A similar type system has been developed by Texas Sampling (www.TexasSampling.com) at an approximate cost of $26,000-$30,000. (See Figure 1C)2005 2006 Duration Ibs S02 sef Duration Ibs S02 sef 500 Lb Case [Bold]

4 min 0.496 293.8 20mln 

# I 1.631.01 197.779.0 

### > 500 of total 

### % %<500Ibs

1 min 0.453 268.9 2 min 3.975 288.5 0.00855 0.85 99.1 2005

2 min 0.074 441.2 2 min 0.127 46.8 0.05600 5.60 94.4 2006

2 min 0.056 333.3 12 min 16.545 5.4831 

### 96.8 Avg

4 min 1453 8,618.7 6min 2.596 2,405.5
2 min 0.090 530.8 8min 61.340 80.690.1 

### 100 Lb Case 

### [Italicized]

1 min 0.697 85.6 17 min 252.625 264,289.4 > 100 of total 

### % %<100Ibs

1 min 0.254 150.6 3 min 0,461 582.2 0.12821 12.8 87.2 2005

2 min 0.170 72.5 27 min 9.783 3,946.4 0.09600 9.6 904 2006

12 min 3.151 1,909.5 6 min 

# I 1.170.818 

# I 593,383.5 88.8 

### Avg

3 min 22.771 665.5 1 min 0.051 35.3
5 min 0.678 659.4 63 min 

# I 3.500.945 

# I 25,148.1
3 min 0.099 585.0 1 min 0.115 42.5 Minutes

2 min 0.028 166.4 10 min 4.399 864.2 Mins of flaring 

### % % uptime

14 min 8.291 2.092.8 5 min 1,385 748.8 2541 048 99.5 2005

3 min 0.044 259.4 2 min 0.307 162.6 1562 0.30 99.7 2006

1 min 0.040 44.8 4min 5.438 724.3 99.6 Avg

46 min 

## 1 297.275 

## 1 32,282.8 4min 0.858 978.0
2 min 1.938 1,149.4 7 min 1.182 1.347.6
1 min 1.338 793.7 1 min 0.063 91.4
37 min 8.660 8,365.9 4 min 0.051 300.6 3 min 2.420 287.0 5min 0.041 242.4
2 Hr41 mi1 

### 375.330 

## 1 '08,537.0 6min 0.469 569.3

3 min 7.913 770.5 2min 0.002 18.2
1 min 0.057 16.2 1 min 0.085 70.1
5 min 0.141 833.3 14 min 8.590 1.732.5
I HR 55 mil 239,972 

# I 33,358.6 18 min 16.898

7 min 1.889 1,166.7 18min 

### 402.207 10.625.4
29 min 1.462 8,668.2 24 min 1.595 1.183.6
1 min 0019 22.9 21 min 

### 390.973 9,994.9
10 min 85.184 4,230.4 1 min 0.589 0.2 4 min 3.369 1,997.7 3 min 0.473 5722
18 min 11.275 5,916.5 12 min 154,632 17,531,9
2 min 0.351 184.3 43 min 5.300 31.429.8
4 min 0.366 2,173.2 4 min 42.425 179.689.1
5 min 30.181 1,737.5 1 min 0.051 18,5
6min 0.203 1,204.3 46 min 521.730 155,462.0
2 min 0070 412.8 9min 1.322 7,840.6
7 min 15.272 1,580.4 2min 0.017 99.5
8 min 12.947 '1,119.1 9min 5.511 3.268.1
53 min 179.256 24,143.6 2 min 0 1.7
24 min 1.386 9,133.9 1 min 0.001 250.5
12 min 4.703 5,261.6 2 min 0.380 1.1
10 min 17.290 813,1 2 min 0.162 94,9
34 min 1.195 4,016.4 9 min 0.305 3,617.5
2 min 0.002 

### 10.6 24 min 

### 70.328 7.168.7
12 min 78.271 5,298,2 1 min 0.076 29.1
2hr 25 mini 216.814 86,931.5 2 min 0.076 31.8

5 min 56,605 2.624.3 13 min 11.665 4.705.2
20 min 

# I 254.794 13,568.9 2 min 0.261 127.7
22 min 6,508 2.901.7 19 min 22.648 9.866.2
22 min 3.177 784.8 4 min 0.300 264.5
55 min 52.163 7,176.5 2 min 0.292 250.7
16 min 

### 105.789 26,137.2 5min 5.843 255.3
65min 3.061 2 min 0.065 26,2
8 min 

# I 266.170 

# I 20,739.9 7 min 8.617 2,903.1
50 min 23.129 13,578.9 3 min 0.842 419.3
6 min 0.025 145.9 16 min 

### 163.086 14,731.6
226 min 

### 104.705 45,449.9 6mln 35,220 9,277.8
137 min 

### 465.510 105,207.7 15 min 16,074 2,564,6
22 min 6.778 4.343.3 8 min 33.109 1,823.1612.1 2,468.4 258.8 795.7 25,948.6

2.1 2,531.5 1,424.9 940.4 47.339.3

3.7 3,062.1

5.8 43.4 66.422.2 11,001.1 2,750.0 3,331.3 1,665.5 13.095.5 1,196.4 349.3 19,851.2 1,455.0 1,338.1

2,871.7

20.9 89.1 6,602.8 150.7 17.0 664,039.4

1,290.5 296.7 211.1 54,612.8

78.9 49,456.9

48.0 23,020.6

683.8 11.7 0.0 683.8 4,564.1 2,698.5

176.3 104.4 3.5 21.2 228.3

7.3 1,3 1,635.7

15.0 603.5 113.3 645.3 403.6 867.4 1,148.4 68.824 38.503 3.258 96.958 20.904 0.330 62.268 41.910 49.601 37.487 89.395 41.476 11.339 738.297

0.002 1.188 0.004 0.745 39.941 4.792 4.883 15.309 40.295 6.909 13.366 14.615 0.001 0.387 0.015 0.024 6.508 1.670 3.103 0.003 

## 1 7,213.087 

## 1 9.402 2.447 0.032 71.877 0.037 84.386 0.030 80.884 13.953 0.004 0.01 13.953 1.770 0.455 0.006 0.164 0.004 0.021 0.010 0.001 0.0004 0.055 0.005 1.364 0.023 0.098 0.197 2.072 0.213 11 min 19min 6 min 22 min 10 min 4 min 43 min 4 min 

### 4 min 15 min 

### 8 min 

### 7 min 

### 3 min 

### 2 hr43

### ml~

2 min 8 min 

### 2 min 2 min 53 min 22 min 10 min 

### 5 min 16 min 

### 2 min 

### 8 min 66 min 1 min 9 min 2 min 2 min 12 min 6min 2 min 

### 2 min 11 min 6 min 

### 2 min 

### 3 min 1 hr 21min

1 min 44 min 

### 1 min 32 min 

### 4 min 

### 1 min 1 min 5 min 1 hr 36 min

23 min 4 min 2 min 1 min 3 min 10 min 2 min 1 min 20 min 3 min 3 min 8 min 7 min 6 min 32 min 9 min 5 min 19.901 2,164.5 2 hr44

### mi~ 287.543 18,570.0

15 min 47.633 

### 3,307.4 4 min 

### 0.022 76.6 20 min 

### 0.040 183.7 2 min 0.051 32.1 7min 18.700 1,820.5 58 min 68.700 27,334.8 28 min 10.000 3,488.3 2 min 0.054 22.6 7 min 

### 0.319 451.9 1 hr 

### 17**mi~** 183.202 

### 66,138.0

6 min 46.924 3,216.7 2 min 0.304 1,638.1 6 min 7.655 590.3 2 min 0.031 183.0 3 min 40.295 1,384.3 1 min 0.111 80.9 17 min 149.887 

## 1 6,435.8 2 min 0.003 151 2 min 1.726 79.9 2 min 0.023 126.5 2 min 0.011 65.8 26 min 78.636 4,342.4 4 hrs 

### 11527.6881 119,395.2 

### 3 min 0.021 75.6 4min 34.623 1,114.0 5min 45.884 6,141.7 60 min 

# 1 230.960 

### 1139,292.8 6min 56.110 6,277.6 6 min 7.209 5,277.4 2 min 2.954 144.4 4 min 2.395 1,753.0 2 min 0.126 92.6 9 min 18.063 937.9 2 min 0.019 111.2 5 min 0.027 163.0 5 min 0.065 642.1 34 min 25.774 127,360.5 9 min 0.836 495.5 13 min 2.453 14,544.9 10 min 3.487 20,675,8 1 min 0.029 172.7 21 min 3.348 12,694.8 15 min 10.973 18,590.8 7 min 

### 9.096 1,840.8 34 min 8.691 51,533.5 2 min 2088 154.4 2 min 0.781 1,322.6 5 min 0.229 1,359.8 5 min 8.437 1,558.5 29 min 1.337 8,581.7 3 min 3.362 678.0 4 min 6.504 1,329.9 11 min 12.806 12,093.0 1 min 0.001 !i.631 2 min 

### 0.021 33.500