P 662-22^406
EPA-600/4-82-054
July 1982
A STUDY TO EVALUATE CARBON MONOXIDE
AND HYDROGEN SULFIDE CONTINUOUS EMISSION
MONITORS AT AN OIL REFINERY
by
Bruce B. Ferguson and
Richard E. Lester
Harmon Engineering 4 Testing
Auburn. Alabama 36830
and
U.J. Mitchell
Quality Assurance Division
Environmental Monitoring Systems Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Research Triangle Park. North Carolina 27711
EPA Contract No. 68-02-3105
Prepared For
QUALITY ASSURANCE DIVISION (MD-77)
ENVIRONMENTAL MONITORING SYSTEMS LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
RESEARCH TRIANGLE PARK. NORTH CAROLINA 27711
KtrKOuUUu bT
NATIONAL TECHNICAL
INFORMATION SERVICE
B5 DEPMIKIII Of COHNEDCE
VDIKGFIEID W. 22161
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DISCUIMEI
This report has been reviewed by the Environmental Nonitorinc
Systeas Laboratory. U.S. Environaental Protection Agency and has been
approved for publication. Approval does not signify that the contents
necessarily reflect the views and policies of the U.S. Environmental
Protection Agency, nor does aention of trade naies or coonercial
products constitute endorsement or recoamendation for use.
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FORWARD
Measurement and monitoring research efforts are designed to
anticipate potential environmental problems, to support regulatory
action* by developing an in-depth understanding of the nature and
processes that impact health and the ecology, to provide innovative
means of monitoring compliance with regulations, and to evaluate the
effectiveness of health and environmental protection efforts through
the monitoring of long-term trends. The Environmental Monitoring
Systems Laboratory, lesearch Triangle Park, North Carolina, has
responsibility for: assessment of environmental monitoring technology
and systems; implementation of agencywide quality assurance programs
for air pollution measurement systems; and supplying technical support
to other groups in the Agency including the Office of Air, Noise and
ladiation. the Office of Toxic Substances and the Office of
Enforcement.
The following investigation was conducted at the request of the
Office of Air Quality Planning and Standards (OAQPS) to determine the
performance that can be expected from continuous emission monitors
installed at petroleum refineries. The results of this study will be
used by the OAQPS to determine the appropriateness of these monitors
for use at refineries and to determine reasonable performance specifi-
cations for these monitors.
Thomas H. Hauser, Ph.D.
Director
Environmental Monitoring Systems Laboratory
Research Triangle Park, North Carolina
111
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ABSTRACT
The U.S. Environmental Protection Agency (EPA) has promulgated
tw Source Performance Standards (NSPS) that require petroleum
refineries to continuously monitor the carbon monoxide (00) emissions
from fluid catalytic cracking (FCC) units and also to continuously
monitor either the hydrogen sulfide (H_S) concentration in fuel gas
feed lines or the resulting sulfur dioxide (SO.) concentration in the
boiler exhaust. However, refineries are not required to install H-S
or CO continuous emission monitors (CEMs) until performance
specifications have been published by the EPA. Tentative performance
specifications, proposed by EPA after laboratory and short-term field
evaluations, were extensively evaluated in a year-long field
evaluation conducted using five HgS and four CO continuous emission
monitors. The H_S CEHs were Installed on a fuel gas line and the CO
CEMs were installed on a stack from a FCC unit at an east coast
refinery. During the evaluation, performance specification testing
was routinely performed on the instruments as the instruments were
operated and maintained in a work environment. The CO CENs were
generally reliable and able to meet proposed performance
specifications. The H_S CEHs were not able to meet the proposed
relative accuracy criteria but the difference in measured
concentration could not be isolated to the CEMs or the reference
method.
IV
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CONTENTS
Disclaimer i
Forward i
Abstract
Figures v
Tables vi
List of Abbreviations and Symbols vii
1. Introduction...... 1
2. Summary and Conclusions 9
Carbon Monoxide Manual Method 9
Carbon Monoxide Monitors 9
Hydrogen Sulfide Monitors , 10
3. Recommendations 20
Carbon Monoxide Continuous Emission Monitors 20
Hydrogen Sulfide Continuous Enission Monitors 20
4. Description of Equipment 22
Continuous Emission Monitors 22
Ancillary Equipment 24
5. Experimental Procedures 29
General Procedures 29
Laboratory Evaluation of the Monitors 29
Field Evaluation of the Monitors 32
6. Results and Discussion 35
Manual CO Method Development/Validation 35
Evaluation of Carbon Monoxide Monitors 40
Evaluation of Hydrogen Sulfide Monitors 48
References 58
Appendices
A. Definition of terms 60
B. Tentative plan for the evaluation of CO and H2S continuous
monitors at refineries 62
C. Vendors response to letter from EPA 70
D. FCC emissions gas sample conditioning system ?3
E. Manual method for measuring carbon monoxide in refinery
gases 80
F. Instrument evaluation history 95
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FIGURES
Number Page
1 Sketch of field evaluation site 8
2 Sketch of instrumentation trailer showing instrument
arrangement 26
3 Plumbing diagram for FCC gas distribution to the CO CEMs.. 27
4 Plumbing diagram for fuel gas distribution to the H_S
CEMs 7 28
5 Zero drift trend for Ecolyzer CEM 45
6 Span drift trend for Ecolyzer CEM 45
7 Zero drift trend for MSA CEH 46
8 Span drift trend for MSA CEH 46
9 Zero drift trend for Anarad CEM 47
10 Span drift trend for Anarad CEM 47
11 Zero drift trend for Bendix CEM 55
12 Span drift trend for Bendix CEM 55
13 Zero drift trend for Houston Atlas CEM 56
14 Span drift trend for Houston Atlas CEM.... 56
15 Zero drift trend for Del Mar CEM 57
16 Span drift trend for Del Mar CEM 57
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TABLES
Number Page
1 Tentative performance specifications for CO CEHs 5
2 Tentative performance specifications for H_S CEHs 5
3 CO CEHs evaluated 6
1 H?S CEHs evaluated 7
5 Data summary of CO CEHs 13
6 Sunnary of CO relative accuracy tests at refinery 14
7 Calibration drift test results for CO monitors IS
8 Effect of C0_, NO , SO- and CO monitors 16
9 Data summary of H-S CEMs relative accuracy tests at
refinery 17
10 Summary of H S relative accuracy tests at refinery 18
11 Calibration drift test results for HgS monitors 19
12 Change in absorbance of CO reagent blank with time at
room temperature 38
13 Effect of NO and SO. on leuco crystal violet 38
14 Comparison between LCV and NDIR results on FCC samples... 39
15 Relative accuracy test results on CO monitors 15
16 Relative accuracy test results on H.S monitors 52
17 Results of collaborative RA test on H2S monitors 54
vii
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LIST OF ABBREVIATIONS AND SYMBOLS
ABBREVIATIONS
CEM
d.c.
EPA
FCC
FID
FPD
FS
GC
HAI
ID
IF
LCV
MSA
NBS
NDIR
NSPS
00
PAI
ppn
PST
PVC
RA
Applied Automation
continuous Mission monitor
direct current
Environmental Protection Agsncy
fluid catalytic cracker
flame ionization detector
flame photometric detector
full scale
gas chromatograph
Houston Atlas, Incorporated
inside diameter
infrared
leuco crystal violet
Nine Safety Appliance
National Bureau of Standards
nondispersive infrared
New Source Performance Standards
outside diameter
Process Analyzers, Incorporated
parts per million
Performance Specification Test
polyvinyl chloride
relative accuracy
SYMBOLS
CH
CH.SH
or
«y
Us
so.
methane
ethyl mercaptan
carbon monoxide
carbon dioxide
hydrogen sulfide
oxides of nitrogen
sulfur dioxide
Vlll
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SECTION 1
INTRODUCTION
On March ID. 1978. EPA promulgated New Source Performance Stan-
dards (USPS) that required petroleum refineries to continuously Moni-
tor the carbon Monoxide (CO) emissions from fluid catalytic cracking
(FCC) units (1). Refineries were required to also continuously
Monitor either the hydrogen sulfide (H-S) concentration in fuel gas
feed lines or the resulting sulfur dioxide (SO ) concentration in the
boiler exhaust (1). However, refineries were not required to install
H_S or CO continuous emission monitors (CENs) until performance
specifications were putlished by the EPA.
Tables 1 and 2 present the tentative performance specifications
for both CO and H.S monitors that were subsequently proposed by an EPA
contractor after laboratory and short-termed field evaluations. Terms
used in these tables and throughout the report are defined in Appendix
A.
In the laboratory phase, candidate instruments were evaluated to
determine:
response characteristics
stability with time, temperature and flow rate
sensitivity to potential interferences likely to be
present in the sampled gas.
The five CO and two H.S monitors that performed adequately in the
laboratory were then evaluated for approximately two months at a
petroleum refinery (2.3). Only one CO monitor and one H_S monitor
performed adequately in the field testing. In the case of the CO
monitors, daily calibration checks were mandatory for reliable opera-
tion of all the instruments, but even with the inclusion of daily
calibration, the contractor questioned the long-term reliability of
the CO monitors. Further, instrument malfunctions, sampling system
malfunctions and data logger malfunctions plagued the field evaluation
of both types of monitors which resulted in a significant amount of
downtime and lost data.
In April 1979. EPA initiated additional work to determine: (1)
information about long-term instrument durability, data validity and
Maintenance requirements of commercially-available CO and H_S CENs at
a refinery; and (2) the validity of the tentative performance specifi-
cations for the instruments. In addition, a manual (non-instrumental)
method for measuring CO was to be developed and evaluated to serve as
an alternate to EPA Reference Method 10.
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To procure the Monitors. EPA contacted vendors of CO and H_S con-
tinuous stack gas monitors by letter and asked them to submit informa-
tion about the Monitor (a) they thought would be suitable for the
appropriate refinery process, the operating principle and approximate
cost. A copy of that letter and the Project Accomplishment Plan that
accompanied it are included in Appendix B. Appendix C contains the
vendor response to the letter and. if they suggested a Monitor, the
odel nuMber. cost and operating principle.
Of the 35 vendors contacted, 16 did not respond. A total of 10
H_S and 13 CO Monitors were recommended for consideration. From this
list, five H_S and four CO monitors were selected for evaluation. The
pertinent information about each instrument is included in Tables 3
and 4. The selection criteria (described in detail in Appendix B)
involved total cost, operation/detection principle and engineering
judgement about the likelihood the monitor would be suitable for the
application. For example, one company proposed to use a converted NO
monitor for Measuring H_S, but did not consider the likelihood that
organics in the fuel gas would interfere with the chemiluninescence
reaction.
After receipt, the monitors were installed in a trailer at the
Harmon Engineering 4 Testing (HE&T) facility in Auburn. Alabama and
were subjected to checks for: drift, response time, electronic noise
level, interferences and response variation due to changes in ambient
temperature and sample flow rate. The monitors and trailer were then
transported to a refinery for an 11-aonth field study in which they
were tested at periodic intervals for relative accuracy, response
time, calibration error and drift.
The refinery at which the field evaluation was conducted had
added a new CO boiler to the FCC unit in early 1979 to recover addi-
tional energy from the FCC exhaust gas and to reduce the CO concentra-
tion in the gas stream. The emission gas from this unit was used for
the CO CEM evaluation.
An EPA-designed sample conditioning system (described in Appendix
0) removed the moisture and particulate matter from the FCC gas at the
sampling port. The conditioned gas was transported to the sample
manifold through 200 meters of 0.95 cm ID black, nylon tubing at a
flow rate ranging from 8 to 15 Lpm. This sample conditioning system
was installed in February 1980, and was operated continuously for
eleven weeks before the monitors arrived at the refinery to allow time
to correct any potential design deficiencies (none were found) before
attaching the Monitors to it. Three measurements of CO. and CO
concentrations performed during this 11 week period indicated these
compounds were not affected by the sample conditioning system. In
these checks, inlet and outlet samples were taken in Tedlar bags and
analyzed by MDIR techniques.
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A sample Manifold was used to distribute the conditioned FCC
stack gas to the four CO CEMs. The distribution system was desired
to vent excess gas not required by the instruments for normal op _ ra-
tion. The unit was also equipped with solenoid valves controlled by a
data logger for automatic zero and span checks each day.
The H.S Monitors sampled a fuel gas line at a point downstream of
the amine greater used to remove H~S from the fuel gas. During the
project, both aonoethanolamine ana diethanolamine were used in the
Mine treater.
The fuel gas was distributed to the five H_S monitors by means of
a six-port sampling manifold that was supplied continuously with
treated fuel gas. The fuel gas was transported from the sampling
point to the instrumentation trailer through approximately 100 m of
0.63 cm 00 stainless steel tubing.
All instruments were located in a 24-foot long, air conditioned
trailer. Figure 1 shows the location of the instrumentation trailer
in relation to the two sources that were monitored.
The output from the monitors was simultaneously recorded on an
Esterline Angus Model PD 2061 data logger. Techtran Model 816 cassette
tape recorder and an Esterline Angus multipoint recorder. While
sampling process gas, each monitor's output was read at 3-minute
intervals and the average value for 10 readings was printed by the
dita logger and simultaneously recorded by the Techtran Model 816.
The multipoint recorder printed each 3-ninute reading without
averaging. During relative accuracy testing, the data logger measured
each monitor's output at 1-ninute intervals and reported the average
every 20 or 30 minutes.
At the beginning of the field evaluation (April 1980). the ten-
tative performance tests listed in Tables 1 and 2 were performed.
Field testing performed after May 1980. however, concentrated on re-
lative accuracy and calibration drift tests in response to a major
change in EPA's overall approach to monitor system performance speci-
fications. This change, formally proposed in the Federal Register(U),
involved a drastic simplification on the Performance Specification
Test (PST) Procedure 4. Under these proposed PST revisions the only
mandatory tests are relative accuracy and calibration drift. The
other tests that were previously required (5) are now optional.
Five CO and ten H_S relative accuracy tests were conducted during
the 11-month field evaluation, but not all monitors were operational
in all tests. In addition, the monitors were subjected to daily 15-
minute zero and span checks. Except for days when relative accuracy
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testing was being performed, zero and span calibrations were not
normally adjusted more often than weekly (frequently less than once
per month) in order to provide data on the drift characteristics of
each instrument. Only the gas chromatograph (GO instruments were
equipped with automatic zero and no instrument was equipped with
automatic span adjustment.
Relative accuracy tests on the H_S monitors used EPA Method 11
(6) as the reference method. Relative accuracy tests on the CO
monitors were conducted using EPA Method 10 and an alternate method
(described in Appendix E) developed during this study. This alternate
method can be used to check the accuracy of CO continuous monitors
using NDIR as the measurement technique..
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TABLE 1. TENTATIVE PERFORMANCE
SPECIFICATIONS FOR CO GEMS
PARAMETERS SPECIFICATION
Range 0-1000 ppa
Calibration Error <2Z Span
Relative Accuracy1'2 1»OZ Mean Rcf.
Value
Precision *1Z Spas..
Response Tl»e (System) <10 Minutes
Output Noise <1Z Span
Zero Drift. 2 Hours <1Z Span
Zero Drift. 24 Hours1 <2Z Span
Spaa Drift. 24 Houra1 <2.5Z Spaa
Interference Equiv.
1SZ CO, aa pp» CO £10 pp*
10Z H,0 as pp* CO 168 Hours
Expressed aa SUB of absolute Man value plus
95Z confidence Interval In a series of testa.
This value Is based on a relative cosiparlson
of the annitors to each other and not to
Method 10. The tares are defined In Appendix
A.
TABLE 2. TENTATIVE PERFORMANCE
SPECIFICATIONS FOR H2S CE1S
PAKAMETEKS
Kan*e
Calibration Error
Relative Accuracy
Response TlM (Systea)
Zero Drift. 2 Hours
Zero Drift. 24 Hours1
Span Drift. 2 Hours1
Span Drift. 24 Hours
Operational Period
SPECIFICATION
0-300 ppa
<5Z of Each
Calibration
Mixture
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SECTION 2
SUMMARY AND CONCLUSIONS
CARBON MONOXIDE MANUAL METHOD
The analytical portion of the manual CO test method developed in
this study was biased 4 percent high with respect to a Bendix 8501-
5CA NDIR CO analyzer. The precision associated with a single analysis
was 4.3 percent of the concentration for the range 10 to 1100 ppra.
The precision was approximately 2.5 percent of the mean concentration
for analyses performed in triplicate. This means that two analytical
results on the same bag sample should differ by more than 8.4 percent
only one time in 20 due to chance alone. The method was significantly
affected by SO, and NO, so these compounds were removed during sample
collection by bubbling the gas through alkaline potassium perman-
ganate.
Table 5 summarizes the data collected for each CO instrument
during the study. Tables 6 and 7 summarize the relative accuracy and
calibration drift tests, respectively. Sometimes, less than the
desired nine manual method tests were achieved because of leaking
Tedlar bags and process failure. Table 8 shows the effect of CO., NO
and S0_ on each monitor's response. The following paragraphs
summarize the performance of each instrument.
CARBON MONOXIDE MONITORS
Applied Automation Optichrom 102
The monitor performed well in the laboratory checkout, but not in
the field evaluation. A valid relative accuracy test was never
achieved because of the monitor's erratic performance; thus, its per-
cent uptime was zero.
Ecolyzer 3107
This monitor was equipped with an Energetics Science Model 2949
scrubber to remove NO and SQ^. Originally, each scrubber cost $21,
but by June 1980, this price had increased to $45. The scrubber was
found to be inadequate for long-term use on FCC gases. scrubber
failure, which in turn caused monitor detector failure, occurred from
1 to 20 days after installation (depending on the NO and SO
concentration encountered). To protect the detector and save cost, a
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25 en long by 2.5 cm diameter PVC pipe containing activated charcoal
was substituted for the Model 2949 scrubber during routine use and the
Model 2949 scrubber used only during relative accuracy tests. The
response time of the system with the large charcoal scrubber installed
was approximately 30 minutes compared to less than 1 minute when'the
Model 2949 scrubber was used. At the S0_ and NO concentrations
normally encountered in an FCC stack (500 ppm SO , 20o ppm NO ) even a
new Model 2949 scrubber was unable to remove all of the interfering
gases such that the instrument could pass a relative accuracy test
(See RA test 2/81 (A) in Table 6). Carbon dioxide at 15 percent by
volume did not interfere. The monitor drifted significantly over a
period of several days at frequent intervals. The detector was
replaced once during the study and the evaluation stopped after the
detector failed the second time. Detector failure was also a problem
in the previous study (2). This instrument does not appear to be
suitable to continuously monitor CO concentrations in FCC emissions.
Mine Safety Appliance (MSA) Lira 202
As received, the output from this monitor was not compatible with
the data logger thus, the laboratory check-out tests were not
completed before the trailer was sent to the refinery. At the
refinery the monitor drifted on a daily basis but, over a month, the
zero and span drift frequently averaged out to less than 3 percent. No
interference was found from SO- or NO and only a small and constant
interference was found from C0_ (1 ppm per 1 percent CO,,). Although
the test was not done, water vapor would not be expected to be a
significant interferent. The monitor successfully completed the
11-month evaluation with only two failures, both of which were
corrected by an optical realignment.
Anarad 501-R
Except for the time it was in transit to the refinery, this moni-
tor operated continuously without an outage from October, 1979 until
testing was completed in April 1981. Interferences from SO- and NO
were not experienced, but small, constant interferences did result
from CO_ (3 ppo per 1 percent CO.) and from water (3 ppm per 1 percent
H-0). Since the stack gas was conditioned to yield a dewpoint of
-20 C, water was not an interferent in the field tests. The monitor's
output was usually more stable than any of the other instruments.
HYDROGEN SULFIDE MONITORS
The H_S CEMs were evaluated in the laboratory prior to the field
testing. Table 9 summarizes the data collected for each H.S
instrument during the study. Table 10 summarizes the relative
accuracy testing performed in the field, and Table 11 summarizes the
10
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calibration drift tests. In some relative accuracy tests, less than
nine reference method samples were collected because plant upsets
increased the H-S concentration above the span range of the monitors.
The following paragraphs summarize the performance of each
instrument.
Bendix Model 7770
This monitor operated continuously from initial start-up until
final shut-down with only four brief outages. Two outages were caused
by a ruptured diaphragm in the sampling valve, one outage occurred
when an operator accidently shorted a circuit in the heater control
unit and the fourth occurred from an obstruction in the process air
supply.
Interferences were not detected during the initial checkout.
However, during relative accuracy tests, a possible interference from
something in the fuel gas was indicated but could not be confirmed.
Since the monitor sampled the fuel gas once every 3.5 minutes, it was
difficult to conduct a relative accuracy test when the H_S level in
the fuel gas was changing rapidly (as frequently occurred). The
instrument generally performed in a reliable manner throughout the
evaluation.
Process Analyzers Incorporated Model 32-230
This monitor operated for less than 3 days during the laboratory
check-out and was returned to the manufacturer for repairs on three
separate occasions. Mechanical failure, electronics failure and
corrosion of parts prevented the monitor from obtaining a valid
analysis of the fuel gas and thus its percent uptime was zero. The
instrument does not appear suitable for use in this application.
Teledyne Model 611 DHCO-20X
This monitor was received approximately 3 months later than
scheduled, which prevented a complete laboratory checkout of the
monitor. A valid analysis of the fuel gas was never obtained because
of interference from diethanolamine and sulfur compounds such as
mereaptans and carbonyl sulfide. The molecular sieve scrubber
originally supplied with the monitor could not compensate for these
interferences. By the time Teledyne supplied an improved scrubber,
the monitor had ceased to operate; thus its percent uptime was zero.
The instrument does not appear to be suitable for use in this
application.
11
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Houston Atlas Model 825R/102
Although this monitor suffered frequent mechanical failure it
did complete most of the field testing program. The most frequent
cau£o of failure was the gas dilution system. This is the same
problem that affected the Houston Atlas instrument evaluated in a
previous study(3). This monitor required a minimum of 4 hours for a
major calibration and, at times, was subject to severe drifting. Some
of the operational problems encountered were due to operator error and
the corrosive environment of the instrumentation trailer. Some data
were lost because the person conducting the daily checks failed to
replace the lead acetate tape in a timely manner.
Del Mar Scientific Model DH-W
This monitor operated for the entire test program without
mechanical failure. However, because rotameters were used to achieve
1:10 dilution of the fuel gas, its calibration changed when density
and viscosity of the fuel gas changed. Sudden changes in the gas vis-
cosity occurred during some of the relative accuracy tests; thus the
agreement between Method 11 and the monitor varied drastically during
some tests. A bias also seemed to exist between the monitor and the
manual method that could not be explained by viscosity changes. Some
data were lost because the person conducting the daily checks failed
to replace the lead acetate tape in a timely manner.
12
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-------
TABLE 7. CALIBRATION DRIFT TEST RESULTS FOR CO MONITORS
CALIBRATION DRIFT8* b (2)
DAY ECOLYZER ANARAD MSA
Zero Span Zero Span Zero Span
Test I
1 1.4 0.4 1.7 0.1 0.6 0.1
2 0.3 4.4 0.2 2.4 0.9 1.2
3 0.2 1.7 0.2 1-6 1.2 2.0
4 0.6 1.0 1.0 0.2 1.4 0.8
5 0.4 0.7 2.0 0.8 2.5 6.2
6 0.9 0.9 2.1 1.5 3.3 3.0
7 1.2 1.6 3.2 4.5 2.9 0
Test 2
1 0.2 7.2 2.4 0.7 0 0.9
2 0.2 0.1 0.2 4.4 1.7 2.4
3C 0.7 10.8 0.4 3.4 5.4 1.3
4 0.2 0.2 0.4 0.3 1.3 3.6
5 0 1.6 1.1 0.4 2.5 3.7
6 0.1 0.9 0.1 1.9 0.2 1.1
7 0.1 0.3 0.5 1.0 0.1 1.7
Test 3
1
2
3
4
5
6
7
0.1
0.3
0
0.1
3.1
2.2
0.7
0.1
3.4
0.4
0.9
2.7
2.8
0.9
0.9
1.3
0
0.6
0.4
0.4
0.2
0.6
1.7
0.7
1.1
1.1
0.1
0.1
0.2
0.2
0.4
0.7
1.8
4.2
0.9
1.2
1.2
0.1
1.2
2.8
1.1
2.8
* Values In table represent the daily drift as defined by the
following equation
[Calibration Gas Concentration - Monitor Reading! x 100%
Monitor Span Value
b
Because long-tern d-tft was of primary concern, the instruments
were not zeroed dally. The values In the table have been
corrected by the daily zero drift.
15
-------
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bration. However
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17
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METHOD
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18
-------
TABLE 11. CALIBRATION DRIFT TEST RESULTS FOR
MONITORS
TEST
NUMBER
Test 1
1
2
3
4
5
6
7
Test 2
1
2
3
4
5
6
7
Test 3
1
2
3
4
5
6
7
Test 4
1
2
3
4
5
6
7
CALIBRATION DRIFT* * (%)
BENDIX
Zero
0
0
0
0
0.1
0.1
0
0
0
0
0.2
0.1
1.0
0.1
0.1
1.0
0.2
0.2
0.1
4.2
4.2
0
0
0
0
0
0
"
Span
0.7
0.7
1.1
1.1
9.2
8.1
0.7
1.1
0
0.7
0.4
2.6
1.1
0.4
1.8
0.7
0.7
1.5
1.5
2.9
4.0
0.7
0
0.7
0
0
0.4
rl'-USTON ATLAS
Zero
0.1
0.3
0.4
0.1
0.3
0.1
6.9
3.5
1.4
4.5
4.2
1.0
0.6
-
0.1
0.3
1.7
5.2
7.6
5.9
2.1
3.1
0.7
0.7
0
0
0
0.3
Valuea la table repreaent the d«lly drlfc defined by
following equation
1 Calibration Cai Concentration - Monitor Readlntl
Span
6.3
4.5
0.3
1.0
13.9
13.9
2.9
10.8
26.0
3.5
3.1
12.8
1.4
11.5
4.9
1.0
15.6
21.5
-
4.9
5.2
3.8
6.6
0.7
0.7
6.6
0
10.4
the
H 1001
DEL
Zero
12.5
9.6
19.5
0.7
4.8
0
2.6
6.6
4.4
1.5
1.5
1.5
0
4.0
1.1
0.4
1.1
10.7
9.9
0
1.5
0.4
0.7
0
0.6
2.0
-
MAR
Span
21.3
30.9
52.6
101
44.0
3.3
8.1
34.2
26.5
2.6
2.6
1.8
0
4.8
7.4
6.6
8.5
6.6
18.4
6.3
3.7
1.1
3.7
0
4.8
12.1
.
Monitor Span Value
b Became long-term drift waa o.' primary concern, the Inetruaentt
were not seroed dally, l^e valuei In the table have been
corrected by the dally tero drift.
19
-------
SECTION 3
RECOMMENDATIONS
CARBON MONOXIDE CONTINUOUS EMISSION MONITORS
The Anarad and MSA monitors successfully completed the 11-month
study and demonstrated that monitors with good drift control are
available and suitable for the measurement of CO concentrations in FCC
emission gas. Based on the results of this study, the following
specifications are advanced for CO monitors.
Calibration Drift. The CEMs calibration must not drift
or deviate from the reference value of the calibration
gas by more than 5 percent of the established span value
of 1.000 ppra over each 24-hour operating period.
Relative accuracy (RA). The RA of the CEMs must be no
greater than 20 percent of the mean value of the
reference method (RM) test data in terms of the units of
the emission standard or 15 percent of the applicable
standard, whichever is greater, as calculated using
Equation 2-4 in Reference 4 and the manual CO method
results as the reference value.
The correlation among the reference method and CEM data, the
number of RM tests and the calculations should be the same as those
given in Section 7 of Performance Specification 2(4).
Because of the possibility of leaks when sampling with Tedlar
bags, the number of samples taken for a relative accuracy test should
be at least twelve with the option of discarding the results from any
three if it appears that leakage has occurred. The relative accuracy
testing should be done while the CO concentration in the emissions is
varying less than 10 percent over the duration of the testing.
HYDROGEN SULFIDE CONTINUOUS EMISSION MONITORS
The performance of the HpS monitors was disappointing. Only three
of the five monitors were suitable for field use and only one monitor
(Bendix) had an uptime in excess of 85 percent. The other two moni-
tors that passed the test suffered severe drift problems. The Bendix
20
-------
sampled a total of 17 times each hour, but each sample duration was
less one second. Thus, the use of the integrated Method 11 sampling
approach for determining the accuracy of this monitor is questionable
unless the fuel gas H_S concentration can be held constant. The
absolute agreement between Method 11 and all the monitors was poor and
variable in eight of the ten relative accuracy tests as shown in Table
10. Since the cause or causes of this difference could not be
identified, the use of H.S monitors for compliance purposes cannot be
recommended at this time.
The monitors may be useful, however, for determining trends and
for indicating amine treater performance, as shown by the overall
agreement between the average for all Method 11 tests and that for
each monitor (i.e.. Method 11-140 ppm. Bendix-119 ppm, Houston Atlas-
130 ppm and Del Mar-133 ppm). (Some Method 11 tests used in calcula-
ting the above averages were not reported in the text of this report
because they represented cases where plant malfunction or instrument
failure caused a relative accuracy test to be aborted before an ade-
quate number of samples had been obtained).
Due to the apparent bias between the Reference Method 11 tests
and the H.S CEM data, an interference to the reference method tests
is suspected. Additional evaluation of the reference method should be
performed before performance specifications are developed and
installation of monitors is required.
21
-------
SECTION 1
DESCRIPTION OF EQUIPMENT
CONTINUOUS EMISSION HONITORS
Carbon Monoxide Monitors
Applied Automation Optichrom 102
The Model 102 is a gas chroraatograph that uses a flame ionization
detector (FID) to detect methane catalytically produced from carbon
monoxide. The oven, valves and controls are located in an air purged
moduli and the programmer is in a separate cabinet. A sample loop is
used to sample an exact volume of gas which is injected onto the
column by a multiport valve. Two columns in series are used for the
separation - when the CO has eluted through the first column, it is
backflushed to remove the heavier components while additional separa-
tion takes place on the second column. A catalytic methanator con-
verts the CO to methane (in the presence of hydrogen carrier gas)
which is detected by the FID.
Automatic zeroing is accomplished via an auto zero control on the
detector immediately before the CO peak reaches the detector. Span-
ning is accomplished by a series of attenuation switches and a fine
attenuation potentiometer.
Ecolyzer 3107
The Ecolyzer Model 3107 monitor utilizes an electrochemical
sensor to measure CO in the ranges of 0 to 1000 ppm and 0 to 500 ppm.
The unit utilizes a sampling pump and a by-pass to vent unused sample
around the sensor. To maintain constant sample humidity, a salt water
humidifer is located upstream of the detector. An absorbent cartridge
is provided for the removal of S02 and NO from the sample gas.
Sample pressure must not exceed 2.5 cm water at the sample pump inlet.
*
.
Mine Safety Appliances Lira 202
The Lira 202 has two IR lamps, a "Luft-type" infrared detector
and gold-lined sample and reference cells. One lamp passes through
the sample cell and the other lamp through the reference cell. The
emergent radiation from both cells is directed to a single detector
cell. As the gas in the detector absorbs radiation, its temperature
*nd pressure increase. An expansion of the gas in the detector causes
the membrane of condenser microphone to distort. This distortion is
converted to an electrical signal which is amplified to produce an
output signal. The entire analyzer is kept at a constant temperature
by a thermostatically controlled heater and blower installed in the
case.
22
-------
Anarad 501R
This NDIR analyzer uses unlined Plexiglass sample and reference
cells. The monitor consists of a single IR source, parabolic mirrors,
chopper, an optical solid state detector and an output module that
can be separated from the rest of the monitor.
Hydrogen Sulfide Monitors
Bendix 7770
The Model 7770 gas chromatograph monitors H.S using an FPD. A
sample block Is used to inject a volume of sample gas onto the first
column. After the H2S has eluted through the first column, the column
is backflushed to remove the heavier components. Further separation
is attained in the second column prior to H.S detection. Zeroing is
automatic during the running program, but a zero offset control is
also provided inside the programmer. The instrument cycle time is 210
seconds. Clean, dry air is used as the carrier gas.
Process Analyzers Incorporated 32-230
The Model 32-230 monitor is a gas chromatograph equipped with a
flame photometric detector (FPD) that is sensitive to sulfur. A
volume of sample is injected into the analytical column from a sample
loop. After the H.S sample has eluted past the first column, the
column is backflushed to remove heavier compounds. The H_S continues
through the second column. At the proper time for the H.S component
to elude through the column, the flame photometric sensing circuit is
activated to detect the H.S. Zeroing is automatic and occurs
immediately before the elution of the peak of interest. Span is
accomplished by adjust- ing an attenuation potentiometer inside the
case.
Teledyne 611 DMCO-20X
This dual beam monitor utilizes ultraviolet absorption to quan-
tify H.S concentration in the sample. A 12-inch-long optical cell has
continuous sample flow. On one end of the sample cell is an ultra-
violet source and on the other end a detector. A rotating chopper
with two filters 180 apart is located between the cell and the
detector. One of the filters passes only a known absorption
wavelength for HgS, the other a wavelength at which H.S does not
absorb (reference beam). The wavelengths are not specified.
Synchronizers and electric circuitry subtract the non-H.S absorption
(reference beam) from the total absorption.
Houston Atlas Model 825R/102
The Model 825R/102 monitor operates on the principle of lead
acetate impregnated paper tape reacting to change color in the
presence of H.S. A cadmium sulfide photocell is used as a detector.
The photocell: output feeds a preamplifier. The output of the
preamplifier feeds a low-pass filter which differentiates the signal
with respect to tine. The resultant differentiated output provides a
DC signal that has a peak amplitude directly proportional to the H.S
concentration.
23
-------
To obtain a sample in the concentration range of measurement by
lead acetate tape, the monitor is equipped with a sliding block dilu-
ter. This diluter mixes a measured volume of sample with a stream of
diluent gas. The amount of dilution is adjusted by varying the in^.-c-
tion frequency of the sample. Zero and span adjustments are made by
adjusting potentiometers insile the case.
Del-Mar Scientific DM-W
The DM-W uses a lead acetate impregnated paper tape that is
exposed to the gas stream as it moves past an aperture. The HgS in
the gas stream causes a black precipitate (lead sulfide) to form on
the tape. Color development is monitored by a photocell that measures
light reflected off the tape.
Because the DM-W normally operates in the 0 to 50 ppm H_S range.
Del Mar supplied a dilution system with the monitor. This system was
comprised of two rotameters, a mixing chamber and a back pressure
regulator. The fuel gas sample was diluted with nitrogen at the
recommended ratio of 1:10 by adjusting needle valves on the
rotameters.
ANCILLARY EQUIPMENT
All monitors and data aquisition equipment were installed in a
24-foot-long trailer equipped with heating and air conditioning.
Figure 2 shows the location of all equipment within the mobile labora-
tory.
The CO source was a stack on a FCC unit. The CO boiler stack gas
contained: 150. to 300 ppm NO. 200 to 600 ppm SO., some acid mist.
50 to 300 mg/nr particulate matter, 10 to 14 percent H.O, 9 to 14
percent CO , and 20 to 10,000 ppm CO. The temperature at the sampling
point was approximately 320 C (600 F).
The H_S source was a fuel gas pipeline located approximately 120
eters from the trailer. Stainless steel tubing (0.63 cm OD) was used
to connect the gas line to the trailer H.S distribution system. The
sampling point was downsteam of an amine treater. When the monitors
were first installed in April 1980, the treater was using diethanol-
amine for the removal of H-S, but in March 1981. the treater was
refurbished and monoethanolamine replaced the diethanolamine. The H-S
level in the fuel line ranged from 5 to over 1,000 ppm during this
study.
Fluid Catalytic Cracker Emission Sampler/Conditioner
An EPA-designed sample conditioning system was located at the
sampling port 60 meters above ground level on the CO boiler stack.
The dried (dewpoint -20 C) and filtered sample was transported 200
meters to the trailer by using unheated. 9.5 nn ID black, nylon
tubing. A detailed description of the sample conditioning system and
its per- forroance is included in Appendix D.
24
-------
Sample Distribution Systems
In the trailer, the gas samples from the sources were distributed
to the monitors by using the distribution (manifold) systems shown* in
Figures 3 and 4. The water column was included on the CO distribution
system to ensure that constant pressure was maintained in the system.
In addition, a pressure reducer was included to ensure that the Ecoly-
zer inlet pressure was maintained below 2.5 cm water. Each distri-
bution systems was fitted with solenoid valves on the span gas and
nitrogen gas lines to facilitate automatic daily zero and span checks
by the data aquisition system.
Data Acquisition System/Automatic Zero/Span System
Each monitor was connected to the Esterline Angus Model PD-2064
data logger. The PD-2064 converted the 4 to 20 mA output of each
monitor to 25 to 125 raV and provided approximately a -25 mV offset.
Each instrument then showed a response on the PD-2064 of 0 to 100 mV.
The PD-2064 is able to monitor all 16 channels continuously or to scan
them at any desired frequency. In addition, the system can scan
selected channels at any desired interval and average the readings for
each channel after the desired number of scans. During the field
testing, each monitor's output was scanned every 3 minutes except when
relative accuracy and calibration error tests were conducted. In
those cases scan times of 1 minute were usually used. After ten
scans, the readings were averaged and the results were printed on the
paper tape. The data and time of printing were also recorded on the
tape.
Every 24 hr, the data logger automatically accomplished a
zero/span check of the monitors. At a set time the data logger closed
the contacts leading to a solenoid valve in the sample distribution
system. This valve shut off the sample gas and opened the nitrogen
(zero) gas. After 15 minutes the data logger took a single reading on
each channel and printed the value. The first set of contacts then
opened and a second set closed to allow span gas to enter. After
15 minutes the data logger again read each channel and printed the
value. The second set of contacts then opened and the original
program of scanning and printing resumed.
EPA Reference Method 11 was used throughout as published. Equip-
ment listings are published in the Method.The manual method for CO
analysis is presented in Appendix E. All equipment is described
therein.
25
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SECTION 5
EXPERIMENTAL PROCEDURES
GENERAL PROCEDURES
Calibration Gases
Calibration gases used for this evaluation were Certified Master
Gases supplied by Scott Specialty Gases, Plumsteadville, PA. Calibra-
tion gases were selected to be 15. 50, and 90 percent of the instru-
ments' span range with nitrogen being the balance. The gases were
analyzed and certified to be +2 percent of the stated values. Method
11 was used to verify the H_S gas concentrations and a Bendix Model
8501 5CA NDIR CO monitor calibrated with NBS standards, was used to
verify the CO gas concentrations.
Calibration Procedures
Each instrument was calibrated according to the manufacturer's
instructions by using the appropriate sample distribution system to
introduce the calibration gas. Calibration curves were generated for
each monitor .
Throughout this ev .luation, all instrumental response readings
were obtained from the digital millivolt output c , the Esterline Angus
PD-2064 data logger. Span and zero adjustments were made on the
instruments to produce a proper millivolt response on the PD-2064 data
logger .
LABORATORY EVALUATION OF THE MONITORS
The monitors were evaluated in the laboratory with the procedures
described in the Federal Register (5). The following parameters which
are defined in Appendix A. were evaluated:
*
precision
noise
response times (rise and fall)
H-0 and CO- interference for CO monitors
and CH-SH interference for H_S monitors
^ - _
flow and temperature variation
29
-------
Precision (Repeatability)
Precision is the standard deviation about the mean of repeated
measurements on the same gas concentration (2). In this test,
measurement of the selected gas (e.g., mid-span) was interrupted
alternately by the introduction of a higher and a lower gas
con;^.itration. Six stable readings of the selected gas were obtained
in this manner and the precision was calculated as follows:
1
6 , . 6
1 P± - i < r PJ
1-1 * 6 1-1 J
L>2
(1)
Where: P a Precision
P. = Instrument response (ppm) for the i measurement
on the selected gas.
Output Noise
Instrument noise is a short-term variation in instrument output
not caused by changes in output concentration. This value is
expressed in concentration units as the standard deviation about the
mean (2)«
The test procedure involved allowing the instrument to stabilize
on the gas standard (either zero or span) and then taking 25 readings
within a 60 minute period by using a digital voltmeter. These
readings (expressed in concentration units) were entered into the
following equation:
v«
25
I
" 25 (
25
E
1-1
(2)
Where: S = Instrument Noise (ppm)
r\ = Instrument Response for the i
Instrument Response Time
th
reading (ppm)
Rise time is the time interval between the initial instrument
response and 95% of the final response after a step increase in input
gas concentration. The test procedure involved changing the input
from zero gas to a high-range span gas and determining the time
required to reach 951 of the high-range span gas concentration.
30
-------
Fall time is the time difference between the initial response and
95% of the final response after a step decrease in input gas
concentration. The test procedure involved changing the input from a
high-range span gas to zero gas and determining the time required^ to
reach 5% of the span value.
To obtain the proper rise and fall times, the "dead volume" in
the sample lines was minimized by placing a three-way stopcock as near
as possible to each instrument's sample port. The sample gas was
switched from zero to span by using this three-way stopcock. The
chart recorder was used at its fastest speed during the test. The
response times were calculated from the strip chart. Three rise times
and three fall times were calculated and the results of each set were
averaged. The instrument response reported in Tables 5 and 9 is the
larger of these two values.
CO., and FUO Interference for CO Monitors
Carbon.dioxide interference was determined by using a Scott blend
of 10 percent CO. in nitrogen. The response to the introduction of
the 10 percent C0_ is expressed in ppm as an equivalent CO
concentration.
Water interference was determined by adding water vapor while the
instrument was sampling nitrogen (zero gas). The response to the
added water vapor was expressed in ppm as an equivalent CO
concentration. Water vapor was added by passing nitrogen through a
flask containing distilled water. The flask was heated sufficiently
to introduce the desired amount of water vapor into the flowing gas
without causing condensation in either the sample lines or the instru-
ment. The water vapor generator was calibrated using EPA Method 4.
Methane and Methyl Mercaptan Interference for h\S Monitors
Methane interference was determined using 99 percent methane.
Each instrument was first zeroed and calibrated according to the
manufacturer's instructions. The methane was then introduced and the
response was recorded as ppm H-S. This same procedure was repeated
using 40 percent hydrogen in methane and 200 ppm methyl mercaptan in
methane. The interference was expressed in ppm as an equivalent H?S
concentration.
Variations in Response Due to Changes in Temperature and Sample Flow
Rate
Variations in instrument output caused by short-term changes in
ambient temperature were measured using zero and span gases. The test
procedure involved allowing the instrument to stabilize at given
roan temperature, recording the response to a gas, changing the
temperature ±10°C and again recording the stabilized response. This
test was performed using the trailer's heating and air conditioning
system to control the room temperature.
31
-------
Variations due to flow rate changes were studied using rotameters
calibrated with a soap-bubble flowmeter. The span gas and the flow
rate were varied from approximately 20 to 500 percent of the recoimuen-
ded sample flow rate. The instrument response was plotted versus the
percent of reconnended flow.
FIELD EVALUATION OF THE MONITORS
Field Response Time
Field response time is the time required for the instrument to
obtain either 90 or 95 percent of the final instrument response after
m step increase in the gas concentration. In the study this included
the time involved for gas flow through the sample conditioning system,
The gas was introduced at the sampling point and the response tinK was
calculated in Banner similar to that used in the laboratory
evaluation of instrument response time.
2-Hr Drift (Zero and Span)
At 2-hr intervals, zero gas (nitrogen) was sampled by the
monitors until all of the monitors had obtained a stable reading;
then, the span gas was introduced to all of the monitors. The zero
and span values were recorded by the data logger and the source gas
was sampled again until the next 2-hour interval was to begin. At
this time the above procedure was repeated. This was continued until
fifteen 2-hour intervals were completed. Instrument zero and span
were adjusted only at 24-hr intervals during this test, and none of
these adjustments were made during the time a 2-hr interval
measurement was being made. The 2-hr zero drift was calculated in the
following manner:
Drift (zero or span) - '1/1 + "1 x 100Z (3)
r Instrument Span
where
- 1 *
d » Z di " Algebriac mean of the differences
dA - (Instrument reading) - (Instrument reading 2 hours later)
n » Number of data points (i.e., the number of d< values)
CI - 95Z confidence interval estimate of the mean value
(4)
32
-------
tQ Q7E. = Student's t-f actor, function of n; i.e.
jn
2 12.706 8 2.365
3 4.303 9 2.306
4 3.182 10 2.262
5 2.776 11 2.228
6 2.571 12 2.201
7 2.417 14 2.160
15 2.145
The 2-hr span drift was calculated in an analogous manner, except
that the span reading was corrected for any zero drift that occurred
in the 2-hr interval.
24-Hour Drift (Zero and Span)
The.data logger automatically introduced zero and span gases into
the sample distribution systems daily and the instrument response was
automatically recorded by the data logger. Seven consecutive values
were obtained over a one week period to establish the 21-hr drift for
each monitor. Zero and span were adjusted only at 21-hr intervals on
an as needed basis. Equations 3 and 4 were used to calculate the
24-hr zero and span drift values.
Calibration Error Test
The calibration error test was performed by first calib-ating
each instrument, then alternately introducing each calibration and
zero gas until fifteen readings were obtained. The difference between
the instrument's response and the actual concentration of each gas was
then calculated using equations analogous to 3 and 4. (In Equation 3,
the calibration gas concentration would be the denominator and not the
span value of the instrument).
Calibration Drift
Data for .this test were taken from the daily zero and span
checks. Zero and span adjustments were made at weekly or longer
intervals.
Relative Accuracy
The relative accuracy of the CO monitors was determined using the
leuco crystal violet wet chemical method described in Appendix E. The
accuracy of the HgS monitors was determined using EPA Reference Method
11 (6). The relative accuracy of the monitors was calculated as
described in Reference 4, i.e.:
33
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_ . . . ... [Idl + CI) x 100Z
Relative Accuracy (Z) -
Mean Value of Reference Method
where
d » Algebraic mean of the difference between
the reference method value and the monitor
value
CI » 95Z confidence internal
34
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SECTION 6
RESULTS AND DISCUSSION
MANUAL CO METHOD DEVELOPMENT/VALIDATION
EPA Reference Method 10 specifies collecting the emission gas
sample in a Tedlar bag and analyzing for CO by NDIR (7). Since NDIR
is the measurement principle used in most CO CEMs. EPA desired to have
a non-NDIR manual method for checking the accuracy of NDIR-equipped
CEMs. Four wet chemical CO methods previously described in the
literature (8-12) were evaluated in this study.
The first method evaluated (8) involves the aqueous reduction of
Pd(II) by CO followed by the addition of KI to yield a red. tetraiodo-
palladium (II) complex, which is then measured spectrophotometrically
to determine the amount of Pd(II) reduced. The amount of CO present in
the gas sample is then calculated on the basis that two moles of CO
reduce one mole of Pd(II). Although this method performed adequately
in the laboratory, it was found unsuitable for gas samples that
contained even 1 ppm NO. For example, the following analytical
results (ppm CO) were obtained on three Tedlar bag samples that
contained 266 ppm CO and the following levels of NO in nitrogen: 225
ppm NO (27 ppo); 2 ppm NO (186 ppm); and 1 ppm NO (223 ppm). The
method suffered from: interference by SO- and organics; sample
instability; poor precision below 100 ppm CO and had a nonlinear
absorption curve. Because of the slowness of the reduction of Pd(II)
ion by CO. the method also required shaking the sample bulb for 2-hr
before adding the KI. For these reasons, work on this method was
terminated.
Three other methods were then evaluated. These methods used
spectrophotometry and the reduction of Pd(II) ion by CO in the
presence of gum arable (9). phosphomolybdic acid/acetone (10) and
leuco crystal.violet/potassium iodate (11, 12). The gum arabic method
suffered from poor precision, sample instability, and interference
from low levels of NO and S02 and required a long reaction time (2 hr
Minimum). The molybdenum blue reaction also suffered sample stability
problems, had poor precision for CO concentrations near the level of
the standard (500 ppm) and required a sample reaction time of 1 hr at
60 C * 1C. Further, in both the gun arabic and phosphomolybdic
methods, the reaction product is a colloid, which means that a
strongly absorbing solution cannot be diluted to bring it into the
linear range of the calibration curve.
35
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The last method evaluated, the leuco crystal violet (LCV) method.
yields a soluble complex that permits sample dilution, has good
precision in the range of 0 to 1000 ppm, and is accurate in .the
presence of low levels of SO- and NO «5 ppm). Some other favorable
featnres are:
the shaking reaction time can be as short as 15 to 20
Inutes for CO concentrations from 50 to 1,000 ppm;
the absorbance increases linearly with increased shaking
reaction time up to 2 hours;
the stock reagents are stable and easily prepared;
the calibration curve is linear in the absorbance range
0 to 1.7:
the complex that is formed absorbs in the visible region
of the spectrum (587 nm) more than 200 nm from where the
reagents absorb. Also, the blank is initially
negligible (Table 12).
Since the LCV method suffers interference from SO. and NO at the
concentrations encountered in FCC stack gases (Table T3), the effec-
tiveness of various scrubbing solutions in reducing these compounds to
less than 5 ppm (without also removing CO) was studied as a function
of flow rate, scrubber volume, concentration and pH, gas volume, and
SOy and NO concentration. The following scrubbing solutions were
evaluated: 6J percent H.O.; 2 percent KMnO^/2 percent NaOH; 4 percent
KMnO /« percent NaOH; 2.5 percent KMnO^/1 percent HNO ; and 2 percent
K2Cr!Jo7/-1 percent HNO-. 3
The best scrubbing system is a flow rate of 0.2 to 0.3 L/min
through three Greenburg-Snith impingers. The first two impingers
contain 400 mL of 4 percent KMnO^/5 percent NaOH and the third 250 mL
of this solution. This system can reduce the SO and NO levels to
less than 5 ppo for a 50-liter gas sample containing 151 Co-t 700 ppm
SO. and 500 ppm NO. Since the impinger system also removes CO.. an
appropriate volume correction is required when calculating the CO
concentration originally present in the gas. A Fyrite analyzer is
suitable for measuring the 002 present in the stack gas.
For field sampling, the original single-sample, ambient air
method (12) was modified to allow the analysis of many samples in a
short period of time under field conditions. Sample stability,
shaking time, shaker type, sample volume, and volume of reagent were
36
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some of the parameters studied to simplify the method as much as
possible and at the same time to optimize its precision and accuracy
at stack CO concentrations.
The method was validated at the petroleum refinery in four field
tests in which the samples were passed through the scrubber solution
nd collected in 10-liter Tedlar bags. These bag samples were re-
turned to the laboratory and analyzed in triplicate by the LCV method
and by NDIR on a Bendix Model 8501-5CA calibrated against NBS
certified CO standards. From forty-one samples collected and analyzed
in this manner, it was determined that the manual method had a consis-
tent 4 percent positive bias with respect to the NDIR. The precision
of the method was determined to be 2.5 percent of the mean concentra-
tion for a sample that contained between 15 and 1000 ppm CO when the
sample was analyzed in triplicate. The Tedlar bag samples were stable
for at least two weeks. Representative analytical results are pre-
sented in Table 11 and the actual method is described in Appendix E.
Since the largest source of error was found to be leaks around
the valve of the Tedlar bags, all bags should be checked for leaks
before use, either by submerging filled bags in water or by pulling a
vacuum ( 25 cm H_0) on the bag and seeing if it will hold the vacuum
for at least 4 hours.
37
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TABLE 12. CHANGE IN ABSORBANCE OF CO REAGENT
BLANK WITH TIME AT ROOM TEMPERATURE
TIME SINCE
PREPARATION
(ia)
0
20
30
45
to
100
120
180
230
280
320
360
THIS STUDY
0.01S
0.01S
0.020
0.030
o.oso
0.080
0.085
0.089
0.100
ABSORBANCE
REFERENCE 11
0.020
0.040
0.07
0.12
0.21
TABLE 13. EFFECT OF NO AND SO, ON LUECO
CRYSTAL VIOLET
SAMPLE SO, MO CO (pp«>
OMBEK (pp») (pp«) ACTUAL FOUND
1 0 200 500 410
2 0 400 500 290
3 700 0 500 290
4 500 200 500 360
38
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TABLE 14. COMPARISON BETWEEN LCV AND NDIR RESULTS ON FCC SAMPLES
TEST
DATE
SEPTEMBER
1980
JANUARY
1981
LCV METHOD RESULTS (ppm CO)
1 2 3 AV
178
121
31.1
78.6
26.5
25.2
28.8
16.7
33.0
1094
356
546
176
181
158
188
81
102
519
258
159
120
31.0
91.1
28.0
24.0
28.0
17.6
30.2
1002
365
592
184
184
145
182
87
114
482
248
163
129
30.1
76.4
27.8
26.9
29.3
16.5
33.2
1111
321
-
182
211
153
189
78
110
536
267
167
123
31.0
82.0
27.0
25.0
29.0
17.0
32.0
1069
347
569
180
192
152
186
82
109
512
258
NDIR (ppm CO)
BENDZX 8501-5CA
149
115
34.0
75.0
26.0
22.0
27.0
19.0
28.0
1005
315
575
178
175
155
181
62
98
539
235
39
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EVALUATION OF CARBON MONOXIDE MONITORS
Five relative accuracy tests were conducted on the CO monitors at
the refinery. The results of these tests are summarized in Table 6
and the results of each run are presented in Table 15. In these
tests, the samples for the manual method were passed through
Greenburg-Smith impingers containing alkaline KMnO^ solution (to
remove NO , SO and organics) and then collected in Tedlar bags. All
samples were collected from the distribution manifold to ensure that a
sample-conditioning system malfunction did not contribute significant
or to the monitor validation procedure.
Tests to verify that CO was not lost in the sample conditioning
system were conducted before each relative accuracy test and at other
times between February 1980 and April 1981. Until September 1980,
these checks consisted of simultaneously collecting stack gas samples
in Tedlar bags at the manifold (distribution box) and at the probe,
and analyzing the bags by NDIR for CO and CO. at the EPA laboratory in
Research Triangle Park, North Carolina. In September 1980, a Bendix
Model 8501-5CA NDIR CO- analyzer was installed in the trailer to con-
tinuously measure the CO. concentration in the gas leaving the mani-
fold. After this, the sample conditioning/sample transport system was
checked monthly and also before each relative accuracy test by
analyzing the stack gas for C02 using a Fyrite analyzer and by
comparing the result to the Bendix 8501-5CA monitor reading. If the
Bendix CO- monitor value differed by more than 0.5 percent from the
Fyrite value, remedial action was taken before the relative accuracy
test was initiated.
The operation of the FCC unit during this 11-month study was
erratic due to FCC failure and process upsets. The CO levels varied
between 20 ppm and 10,000 ppm 00 over a period of several days;
frequently, the particulate emissions were much higher than the 50 to
100 mg/m normally present. Each time a relative accuracy test was
conducted, the CO concentration in the stack exceeded the 1,000 ppm
span range of the monitors, so plant instrument air was introducted at
the probe to bring the CO concentration into the operating range of
the monitors. This dilution also reduced the NO and SO. concentra-
tions in the sample gas by factors of 4 to 10.
During each relative accuracy test, a cylinder gas containing 100
ppm CO, 12 percent CO.. 500 ppm S0_, and 200 ppm NO in N_ was intro-
ducted at the manifold for 30 min and the monitors' output was
recorded while the Tedlar bag sample was taken for analysis by the
manual method. This served three purposes. First, it showed how the
monitors would perform when sampling a stack gas representative of FCC
exhaust gases. (Recall, it was necessary to dilute the stack gas with
air to bring the CO level into the range of the monitors.) Second, it
served as a control sample to establish how constant monitor's
response was to the same sample over the length of the study. Third,
it provided a sample of known CO concentration so that the accuracy of
the manual method (sampling and analysis) could be established.
40
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During each of the 30-minute relative accuracy tests, the monitor
output was read at 1-ainute intervals. The first test, conducted in
June 1980, was unsatisfactory because the manual method be ins?
evaluated (palladium/potassium iodide) suffered sample stabilit,
problems and interference from NO. Thus, the only way to evalua*
onitor accuracy in this test (Table 15) is to compare one monitor to
another (Runs 1-9) or to compare their response to the 100 ppm 00
cylinder (Run 10).
However, since the other four relative accuracy tests were done
using the LCV method, satisfactory manual method results were
obtained. The fourth and fifth relative accuracy tests were performed
during the same week. In the fourth test, three gas cylinders
containing 500 ppm CO, 12 percent C0_, and different levels of SO- and
NO were employed to see how the monitors would perform if sampling an
undiluted FCC stack gas. As expected, the Ecolyzer detector failed
during the test from exposure to N0_ and SO. which were not effec-
tively removed by the Model 2949 scrubber, ui the first three rela-
tive accuracy tests, the Anarad and MSA monitors were quite stable,
but, by the last two tests, they somtimes drifted up to 5 percent of
span over several hours, but at other times remained stable for a day.
This drift sometimes occurred only in the span and at other times only
in the zero setting. No explanation is available for the difficulty.
As mentioned earlier, the only problem encountered with the LCV
manual method was the tendency of the Tedlar bag to leak at the point
where the valve enters the bag. This was a significant problem only
in the fourth relative accuracy test where new sample bags were used
and a small leak was found at the metal washer that served as a gasket
between the valve body and the bag. This leak only occurred when the
sample was withdrawn from the bag and for this reason was not detected
when the bags were leak-checked by inflating them before use.
Two calibration error tests were performed: the first in May 1980
and the other in June 1980. The results are presented in Table 5.
The interference of CO, on the monitors remained constant throughout
the study.
Figures 5 through 10 show the long-term zero and span drifts in
the CO monitors. These data, which were collected frcm Nay 1980 to
January 1981, 'were used to determine the calibration drift of the
instruments. (Recall that: (1) only the Applied Automation had auto-
matic zero and that none of the instruments had automatic span
correction; (2) the zero and span of the monitors were checked every
24 hours; and (3) except when relative accuracy tests were being
conducted, the zero and span of the monitor a were never adjusted at
intervals shorter than 1 week.)
41
-------
Applied Automation Optichrom Model 102
The instrument Is comprised of two modules, a programmer ,and a
GC-oven assembly. It was purchased without vendor installation and
interconnecting wiring was not furnished, the instruction manual was
fur fished three weeks after the instrument was received; hence, the
monitor was not operational as received. Extensive time was required
to complete the instrument wiring and install the circuit boards.
After the monitor was wired and installed, numerous startup problems
were encountered. After a serviceman was sent by Applied Automation,
it was determined that wire of too small a gauge had been used for the
interconnecting wiring. Numerous other difficulties were encountered
in obtaining the correct output signal.
To adjust the span, a lengthy procedure requiring a strip chart
recorder and many adjustments is necessary. After the initial span
adjustment, a trial-and-error method is used for fine tuning, al-
though it is not specified in the instruction manual.
The response time is limited by the cycle time of the analytical
program. The GC completes a cycle every 105 seconds. Varying the
flow or pressure causes no response variance because a sampling loop
vented at atmospheric pressure is used. An oven maintains a constant
temperature for the chromatographic columns. Since the sample value
is ambient temperature or in a thermostatically controlled area, it
was not affected by changes in ambient temperature or sample gas flow
rate.
In June 1980, a negative concentration was sometimes measured by
the instrument. After careful examination of the chrooatogram. this
problem was related to a negative signal dip that occurred immediately
before the CO peak eluted. Several trips to the refinery were made by
HE&T personnel to repair the instrument with no success. In November
1980, Applied Automation performed a service call. After two days of
work, the serviceman still could not correct the problem and further
testing of this Instrument was discontinued.
Eeolyzer 3107
This instrument performed without failure during the laboratory
testing. Special provisions were necessary to ensure that a sample
pressure of no more than 2.5 cm water pressure was present at the
sample inlet port. The span and zero adjustments were not responsive
and thus a slow drift in zero and span followed any adjustment in
these controls.
Sample flow variations from 0.5 to 1.5 times the recommended rate
caused response variations of 10 percent reduction and 3 percent
increase, respectively. In varying the ambient temperature from 10°C
to 30 C no change in response was observed.
-------
For removal of NO and SO. from the sample stream, a gas scrubber
cartridge (filter Model 2949) was supplied. This was located inside
the case and required removal of the sensor for replacement. Because
of the extremely short lifetime of these filters and the difficulty in
replacement, the filters were relocated outside of the case during the
field evaluation. Normal life expectancy of these filters in stack
gas containing 500 ppm S02 and 300 ppo NOX is 1 to 5 days. These
filters cost approximately $45 (a considerable operating expense).
Filter failure caused damage to the electrochemical sensor (requiring
replacement at considerable cost).
MSA Lira 202
The MSA Lira 202 operated as received. After less than a week of
operation, the power supply and output signal circuit boards failed.
After -the boards were replaced, satisfactory output in the range of
H to 20 mA could not be obtained, despite several replacements of each
of these circuit boards.
In June 1980, an MSA serviceman corrected the problem. Instead
of using the 4 to 20 mA output on the instrument, he used an isolated
external converter to convert the normal 0 to 100 mV output to 4-20
mA. After this repair, the monitor operated well throughout the
evaluation. Occasional optical realignment was required to maintain
calibration. Excessive drift was sometimes observed?
Tests for response variation due to sample flow rate and ambient
temperature changes were not peformed due to the late arrival of the
instrument.
Anarad 501R
This NDIR monitor performed without any difficulty during the
evaluation. No special provisions were necessary for the sample gas
except that there had to be free discharge from the sample exit port.
Sample flow variation from 0.3 to 5 times the recommended rate caused
response variations of less than 1 percent. Varying the ambient
temperature from 10 C to 30 C did lot affect the response. Carbon
dioxide and water did give a slight positive interferences. Overall,
the instrument*proved to be extremely accurate and reliable.
43
-------
TABLE 15. RELATIVE ACCURACY TEST
RESULTS ON CO MONITORS
Kit M
Mt
ilrm ee)*
It T«.» 1 (W»l. 101
1*7
III
II
U
1*
U
IN
1M
IN
Jt»
III
1*
M*
II*
111
1*1
117
M
II
141
7*
III
m
m
441
IN
IM
17>
III
111
IM
14!
17
44
174
m
417
M7
17*
MO
7J
11
41
41
100
I
104»
IM
III
111
107
IM
U7
1010
171
III
114
zo*
IM
IO94
M>
1*4
»
104
XI
414
J«t
171
»>
n
in
tl*
\
II
11
II
II
12
II
II
11
12
J17
111
107
471
117
4t7
101
44J
in
M7
un
IUO
IMO
1100
lilt
14*4
1MI
M7
M*
4M
Ml
Mt
141
Sit
SI4
4*7
4*7
11*
111
510
X»
Ml
Ml
M7
m T««« i (F.*. ID
,f
f
3"
4?
5?
4*
7*
§
»
"-
711 j
741
701
MA
**4
711
M*
Ml
7*1
- 711
71J
74S
m
7S1
7*1
Ttf
7M
71*
71*
1 7M
711
721
7l»
7M
731
771
7S1
771
71*
,.
air.
i «tr.
.~<: 100 M. co: MO n. 10. no . «o.
uefe «* lll«tl«« I:* vttb t
luck 4llvil«» Itl* wttk
uct ) «»r ! .. ._< MO M» CO; »O» rt> »,; in CO,; talMc* ,.
CrllMar » «<: M* M> CO: Ml ffm wa. '." n* m}. in CD,: *!
-------
* JMt« MM l«tl»
«« OCT KM MC « r»
FIGURE 5. ZERO DRIFT TREND FOR ECOLYZER CEM.
1M I*4|C1C» ulikntt
cc«cr«ci^-
Awt* «^M fall«r« tec*
It H>T «CT w» MC « '!
FIGURE 6. SPAN DRIFT TREND FOR ECOLYZER CEM.
-------
tf^
M urt OCT i«» KC j«
FIGURE 7. ZERO DRIFT TREND FOR MSA CEM.
FIGURE 8. SPAN DRIFT TREND FOR MSA CEM.
46
-------
«n OCT «ov etc tim nt mm
FIGURE 9. ZERO DRIFT TREND FOR ANARAD CEM.
FIGURE 10. SPAN DRIFT TREND FOR ANARAD CEM.
47
-------
EVALUATION OF HYDROGEN SULFIDE MONITORS
The results of the nine relative accuracy tests are sunnarized in
Table 10. The individual test results are presented in Tables 16'and
17. From an examination of the data, the following observations are
made'
1. When two laboratories simultaneously conducted a rela-
tive accuracy test of the monitors, very good agreement
was obtained between the laboratories, but their results
differed significantly from the monitors' results (Table
17. RA Test 5).
2. A monitor could compare well one day but poorly the next
(Table 16, RA Test 4A, 4B). The overall agreement
between Method 11 and the monitors, as measured by the
relative accuracy tests, was quite variable over the
length of the study (Table 16). This variability was
also noted in the previous short-term study (3).
3. Generally, the Bendix and Houston Atlas monitors
measured H_S concentrations lower than Method 11, but on
one occasion (RA Test 6, Table 16) the Bendix measured
H-S levels higher than Method 11. Experiments to
determine the cause of these differences were
inconclusive. When the fuel gas was spiked with known
amounts of H_S upstream of the manifold, the spike was
adequately recovered by both the monitor (Bendix) and
the Method 11 procedure. During these tests, (February
and March 1981) the Houston Atlas monitor was not
operational and the Del Mar was drifting severely, so
only the Bendix results were reliable. The two
laboratory collaborative test (Table 17) shows that the
difference in concentrations was not due to laboratory
bias in Method 11. Both Method 11 and the monitors
agreed well when analyzing H.S in nitrogen cylinder
gases.
4. When the eighteen, 30-minute tests (Table 16, RA Test MA
and IB) were grouped to yield nine 1-hour tests, the
relative accuracy of the monitors with respect to Method
11 did not improve significantly. This indicates that
increasing the sampling time to 1 hr does not
significantly improve the results obtained.
Figures 11 through 16 show the long-term zero and span drift ob-
served in the H-S monitors. These data, which were collected from
May 1980 to January 1981, were used to determine the calibration drift
of the instruments. (Recall that: (1) only the Bendix and PAI had
automatic zero and that none of the instruments had automatic span
-------
correction; (2) the zero and span of the monitors was checked every 24
hr; and (3) except when relative accuracy tests were being done, the
zero and span of the monitors were never adjusted at intervals shorter
than one week).
Bendix 7770
This instrument is equipped with numerous safety devices Includ-
ing automatic shutdown and start up if certain hazardous conations
exist in the analyzer. A molecular sieve was added to the carrier air
and hydrogen supply to ensure contamination free gases. The Bendix
operated 89 percent of the time during field evaluation. Host of the
downtime was attributable to two pneumatic valve failures; the down-
time was lengthened due to personnel not being on-site to replace the
part.
The flow variation and ambient temperature change tests were not
applicable to this instrument because it used a heated sampling block
to inject a constant and known volume of sample into the chromotagraph
column, regardless of the sample flow rate. The cycle time of the
instrument was 210 sec. For this reason, the time from injection to
100 percent response was used in the laboratory evaluation for
response time rather than from first response to 95 percent of the
final response.
The results of the precision, drift, noise and calibration error
tests were excellent. Relative accuracy testing showed a consistent
difference between the monitor and Method 11 for the fuel gas. The
agreement was always good for HgS in nitrogen. An interference in
either the monitor or the reference method was indicated.
Process Analyzers Incorporated 32-230
This instrument never functioned properly. Many hours were spent
troubleshooting circuit boards to attempt to find the cause for the
lack of a proper output signal. The schematic wiring diagrams
furnished in the operating and maintenance manual were not in agree-
ment with the actual wiring. The unit was returned to the manufac-
turer for repair. After more than 4 weeks, it was returned to HE&T
and installed in the test trailer on the final day of the first field
evaluation. Before the next scheduled field evaluation, the monitor
again failed due to a worn sample valve.
The output of the monitor was not the 4 to 20 mA specified in the
equipment order; and thus the monitor was not compatible with the data
aquisition system. Thus, its output was recorded on the narrow
recorder supplied with the monitor. After several breakdowns, the
onitor was shut off and its evaluation was discontinued.
49
-------
Teledyne 611 DMCO-20X
This instrunent required alignment of the chopper by using an
oscilloscope prior to operation. Severe instability caused by any
ovenent or vibration necessitated that laboratory testing be done at
night when wind or personnel would not cause movement of the
evaluation trailer. Significant interferences were caused by methyl
mercaptan and other compounds found in fuel gas. The molecular sieve
scrubber provided with the instrument could not correct the
interference. An alternate scrubber was eventually furnished but
complete failure of the instrument had already occurred. Because of
multiple factors preventing acceptable operation of this monitor
testing was discontinued before a valid test was achieved (See
Appendix F). »
Houston Atlas 825R/102
The instrument performed properly as received. The instrument's
gas dilution system was not affected by sample flow rate or pressure
changes, but it was affected by ambient temperature changes. That is,
increasing the ambient temperature decreased the response in accor-
dance with the ideal gas law. This affected the accuracy of the dilu-
tion.
Because of a wiring defect, the instrument did not operate during
the first field test and was returned to the manufacturer. It was
rapidly repaired and returned to the refinery.
Extremely large variance in the daily span values (10 to 30
percent) during the first 8 months of operation r'esulted from water
condensation in the sample vent line. Increasing the downward slope
of the vent line eliminated the problem.
The pneumatic actuator for the dilution system failed twice
during the field evaluation causing monitor downtime. No specific
interferences were detected but the general agreement between Method
11 and the monitor was not within the desired 10-percent range. Each
time the lead acetate tape was changed, the monitor required recali-
bration. This required a minimum of 2 hr due to the instrument's slow
response to calibration adjustment. A roll of tape lasted
approximately 14 days.
Del Mar Scientific DH-W
The instrument operated as recieved, but before continuous
operation was possible, the tension on the tape take up reel belt had
to be increased by shortening the belt. The gas dilution system
supplied by the vendor was inadequate. It was comprised of two rota-
meters (one for sample and one for dilution gas), a mixing chamber and
a back pressure regulator. Slight changes in sample gas viscosity and
50
-------
changes in both sample and dilution gas flow rate and pressure caused
drastic calibration shifts in the instrument. Large volumes of
dilution gas (10 L/min) were specified by the manufacturer. At thi^
rate, a cylinder of nitrogen would last 1 day. Thus, to conserve gas ,
both simple and dilution flows were reduced to 15 percent of* :--.e
recommended rate. Adverse effects were not noted by this reduction in
flou'.
Variations in sample pressure greater than 1 psi caused large
variances in the sample flow to the dilution system, which in turn
caused poor results in precision, noise and drift evaluations. The
major problem with the instrument appeared to be the sample gas
dilution system.
51
-------
TABLE 16.
RELATIVE ACCURACY TEST RESULTS ON H2S MONITORS
TEST AMD METHOD 11 r . '"ERENCF (Method 11-Monitor) (nnm HjSl
DATE RESULTS U:. .X HOUSTON ATLAS DEL MAR
(pp« HjjS)
-------
TABLE 16.
RELATIVE ACCURACY TEST RESULTS ON HjS MONITORS
TEST AND
DATE
RA Test 4
5
6
7
8
9
10
11
12
13
Mean
RA Test 4B
14
-15
16
17
18
19
20
21
22
Mean
RA Test 6
1
2
3
4
5
6
Mean
RA Test 7
1
2
3
4
5
6
7
8
Mean
METHOD 11
RESULTS
(ppm HjS)
(l/20/81)b
222
195
190
188
171
179
195
182
186
190
(l/20/81)b
174
177
203
209
198
208
198
206
203
197
(2/25/81)d
285
151
71
97
128
168
150
(2/25/81)
131
281
62
145
' 203
238
27
12
T37
DIFFERENCE
BENOIX
(PP-)
51
24
24
20
4
11
24
14
22
22
1
5
25
24
15
29
21
27
27
19
22
16
-1
6
0
10
9
17
48
20
43
64
67
27
16
38
(Continued)
(Method 11-Monltor)
HOUSTON ATLAS
(Pf»)
c
e
16
16
2
5
28
17
19
15
2
8
18
28
30
54
47
57
56
33
c
c
c
c
c
c
-
c
c
c
c
c
c
e
c
-
(pp> HjS)
DEL MAR
99
72
- 5
0
- 7
3
10
-95
-70
1
- 97
- 92
- 31
- 28
- 33
- 31
- 33
- 43
-108
- 56
c
c
c
c
c
c
-
c
e
c
c
c
c
c
c
-
52
-------
TABLE 16. RELATIVE ACCURACY TEST RESULTS ON H2S MONITORS
TEST AMD
DATE
METHOD 11
RESULTS
(pp. HjS)
DIFFERENCE (Method ll-Monltor)
BENDIX
HOUSTON ATLAS
RA Test 8 (3/31/81)
1
2
3
A
S
6
7
8
9
10
Mean
64
116
171
70
115
1S3
212
77
78
84
114
13
6
/ 16
14
0
-9
-1
IS
12
18
8
c
c
c
c
c
c
c
c
c
c_
27
62
70
10
26
-2
9
4
-1
9
19
" Fuel gas Maple collected in a Tedlar bag taken at this tine and analyzed
by GC one day later showed less than 2 ppm H.S.
1^ ^
30-*inute run*.
Monitor noc operational.
Fuel gas was spiked with known ascunt of H^S for all six runs.
53
-------
W
ee
o
H
z
C£
W)
Z
0
H
U
H
^5
OS
u
t-t
H
|
CQ
|
u
Ox
O
(A
H
OT
1
^
W
1
.
^
O
0
1
~* «ft
Tl n
II
w^*
ftj
5
u
t
»rf
o
1
5
oe
*
u
o
in
i
i
§
s
|
65
M
*
^1
**
2
3
_
a
3
N
3
3
3
04
m
I
B
e
, «,-*«_ 0
1(1111111
i*. M> «n f> « IM ,» 1
1 1 I 1 i i i i I
i " T i ? T "? 7 T
^^ n 0 r^ O ** f"* ^
i i i i i i i i i
1 CM * i m n - f» fs
1 I I ! 1 I I I 1
1 1 1 1 1 1 l 1 l
t 1
00
OD
^\
*
^
T
o
~I
1
?
o
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o
T
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5
e
_c
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3
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^
O
%
O
Q
!
u
3
0
w
X
X
4
I
|
V
II
c
-------
i-r.*-
FIGURE 11. ZERO DRIFT TREND FOR BENDIX CEM.
!
*.-
«
T
""y
^J>
t
A.
i3
«
i
tailM
|M 1
»
I '
.
K IU
MC*I
in
Men
(1
J
-
Ifltfic*!
traclw.
»( kr*i
HKC r«yl
c.l lit
*t*m
ItM
CUB
M «»t KT
FIGURE 12. SPAN DRIFT TREND FOR BENDIX CEM.
55
-------
* - tot. » f«ll«».
FIGURE 13. ZERO DRIFT TREND FOR HOUSTON ATLAS CEM.
I
I'H.
"1
f
B»>»« luw tftlCMifm
I
1
OCT « etc «
FIGURE 14. SPAN DRIFT TREND FOR HOUSTON ATLAS CEM.
56
-------
M Mrr KT mo* ate itm m
FIGURE 15. ZERO DRIFT TREND FOR DEL MAR CEM.
FIGURE 16. SPAN DRIFT TREND FROM DEL MAR CEM.
57
-------
REFERENCES
1. Standards of Performance for New Stationary Sources.
Petroleum Refineries. Federal Register. 43:
10866-10873, March 15, 1978.
2. Repp. H. Evaluation of Continuous Monitors for Carbon
Monoxide in Stationary Sources. EPA 600/2-77-063. U.S.
Environmental Protection Agency. Research Triangle Park.
NC, 1977. 155 pp.
3. Maines, G.D., and W.C. Kelly. Determining Laboratory
and Field Performance Characteristics of H.S Monitoring
Systems as Applied to Petroleum Refinery Fuel Gas Lines.
Draft Final Report, EPA Contract 68-02-2707. Scott
Environmental Technology, San Bernandino, CA, 1978.
4. Standards of Performance for New Stationary Sources.
Proposed Revisions to General Provisions and Additions
to Appendix A. and Reproposal of Revisions to Appendix
B. Federal Register, 46: 8352. January 26. 1981.
5. Standards of Performance for New Stationary Sources.
Appendix B. Performance Specifications Federal Register,
40: 46250, 46271, October 6, 1975.
6. Determination of Hydrogen Sulfide Emissions from New
Stationary Sources. Petroleum Refineries. Federal
Register. 43: 1495, January 10, 1978.
7. Determination of Carbon Monoxide Emissions from New
Stationary Sources. Petroleum Refineries. Federal
Register, 39: 9319-9323. March 8. 1974.
8. Allen, T.H., and W.J. Root. Colorimetric Determination
of Carbon Monoxide in Air by An Improved Palladium
Chloride Method. J. Biol. Chem., 216; 309-17, 1955.
9. Anonymous, Determination of Low Concentrations of Carbon
Monoxide. J. Soc. Chem. Ind., 57: 79-82, 1938.
58
-------
10. Polls, B.D., L.B. Berger, H.H. Schrenk, Colorimetric
Determination of Low Concentrations of CO by Use of a
Palladium Chloride - Phosphomolybdic Acid-Acetone
Reagent. Publication No. 3785. U.S. Dept. of Interior.
Bureau of Mines. Report of Investigations, November
19««. 16 pp.
11. Weins. R.E. Coloriraetric Methods for the Determination
of CO in Air. Thesis. Kansas State University.
Manhattan, Kansas 1973. 32 pp.
12. Lambert. J.L.. and R.E. Weins. Induced Colorimetric
Method for Carbon Monoxide Anal. Chem.. *46: 929-930
59
-------
APPENDIX A
DEFINITION OF TERMS
Calibration Drift - The difference in the monitor's output
readings from the established reference value after a stated
period of operation during which no unscheduled maintenance,
repair, or adjustment has taken place.
Calibration Error - The difference between the pollutant
concentration indicated by the continuous monitoring system
and the known concentration of the test gas mixture.
Interference Equivalent - Positive or negative response
caused by a substance other than the one being measured.
Operational Period - A minimum period of time over which a
measurement system is expected to operate within certain
performance specifications without unscheduled maintenance.
Output Nnise - Spontaneous, short duration deviations in the
analyzer output that are not caused by input concentration
changes. Noise is determined as the standard deviation
about the mean expressed as a percentage of full scale.
Precision - Variation about the mean of repeated measure-
ments of the same pollutant concentration, expressed as one
standard deviation about the mean.
Range - The minimum and maximum measurement levels.
Relative Accuracy - The degree of correctness with which the
continuous monitoring system yields the value of gas
concentration of a sample relative to the value given by a
defined reference method or the emission standard.
Span Drift - The change in the continuous monitoring sys-
tem's output over a stated period of normal and continuous
operation when the pollutant concentration at the time of
measurement is the same known upscale value.
60
-------
System Response Time - The time interval between a step
change in pollutant concentration at the input to the
monitoring system and the time at which 95* of the
corresponding value is displayed on the system data
recorder.
Zero Drift - The change in the continuous monitoring system
output over a stated period of time of normal and continuous
operation when the pollutant concentration at the time of
the measurement is zero.
61
-------
APPENDIX B
TENT< !VE PLAN ^R TH£ VALUATION OF 0
AND H2S CONTINUo^o MONIT^: ' AT REFINERIES
by
William J. Mitchell
Quality Assurance Division
Environmental Monitoring Systems Laboratory
U.S. Environmental Protection Agency
Research Triangle Park, NC 2771.
APRIL 1979
62
-------
UNI'?D STATES ENVIRONMENTAL PROTECT ON AGENCY
«-. iRONMENTAI ' 'ORIN T"S t/-
RE'_ TRIAf. >" ~ .ired petroleum
refineries to install such monitors, but only after EP' developed
performance specifications for these monitors. The objective of our
program is to evaluate tentative specifications recommended for these
monitors by an EPA contractor.
The program will involve installing CO and H-S stack gas monitors at
a petroleum refinery and operating and maintaining these monitors for
approximately one year. The 1979 Pollution Engineering Yearbook and
Product Guide indicates that you may have one or more monitors that could
be used in this study. If this is correct, we would appreciate receiving
information about your monitor as an aid in planning our program. For your
convenience we have enclosed an attachment with this letter that outlines
the information that we need.
For your information and comment, I have attached a copy of our
tentative plan. We anticipate that the H-S continuous monitors will be
monitoring a stack gas that will be comprised primarily of methane and
hydrogen and contain 30-500 ppm H-S, 10-500 ppm mercaptans and some SO--
The CO monitors will be monitoring a flue gas that will have the following
character: 25-800 ppm CO, 8-15% CO-; 200-600 ppm SO-, 200 ppm NO, 8-12%
H-0, and particulate concentrations between 25-150 mg/m .
If you wish to submit information about your monitor(s) or need
further information, please write to me at the address above or call
me at (919) 541-2769.
Sincerely yours,
William J. Mitchell, Ph.D., Chemist
Source Branch
Quality Assurance Division (MD-77)
Attachments
63
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TEK'TIVE PLAN FO.- ! T EVALUATION OF '0
AND H2S CONTINUOUS MOM '~'RS AT REFINEhlcS
I. BACKGRQ.
On March 15, 1978. EPA promulgated New Source P-.: formance Stan-
dards that required petroleum refineries to continuo-sly monitor the
CO emissions from fluid catalytic crackers and the H_S levels in fuel
gas feed lines. However, at the time the regulation were promul-
gated. EPA did not have performance specifications available for the
CO and H_S continuous monitors. Therefore, the refineries are not
required to install the monitors until these performance specifica-
tions are developed.
Tentative performance specifications for both CO and H-S monitors
have now been advanced based on laboratory and field evaluations done
by Scott Environmental Technology. In the laboratory phase of Scott's
program, candidate instruments were evaluated to determine response
characteristics, stability with time, temperature and flow rate, and
sensitivity to potential interferences likely present in the stack
gas. Instruments that performed adequately in the laboratory were
then evaluated at a petroleum refinery to establish their field
performance.
Five CO monitors and two H.S monitors were evaluated at the
petroleum refinery during field trials that lasted approximately 55
days. Only one CO monitor and one HpS monitor performed adequately.
In the case of the CO monitors, daily calibration checks were manda-
tory for reliable operation of the instruments, but even with the
inclusion of daily calibration, Scott questioned the long term
reliability of these monitors. Instrument malfunctions, sampling
system malfunctions and data logger malfunctions plagued these field
evaluations.
Based on these studies, Scott proposed tentative performance spe-
cifications for both CO and H^S monitors. The proposed CO monitor
specifications are summarized in Table B-1. The proposed H-S monitor
specifications are the same as those described in EPA Performance
Specification 2 - "Specifications and Test Procedures for SO- and NO..
Continuous Monitoring Systems in Stationary Sources."
64
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TABLE B-1
RECOMMENDED 'ERFORMANCE ^ECTFT'VTIOM3 FOR
CONTINUOUS ONITORS OF v.A«BON MjN'JV.DE AS
APPLICABLE TO PETROLEUM REFINtMES
PARAMETERS SPECIFICATION
Range 0-1000 ppm
Calibration Error £21 Span
Relative Accuracy £101 Mean Ref. Value
Precision £1% Span
Respone Time (System) £10 Minutes
Output Noise £11 Span
Zero Drift. 2 Hours £11 Span
Zero Drift. 21 Hours1 £21 Span
Span Drift. 24 Hours1 £2.5% Span
Interference Equiv. 15% C02 £10 ppm
Interference Equiv. 10X HgO £5 ppm
Operational Period 168 Hours
Expressed as sum of absolute mean value plus 951 confidence
interval in a series of tests. This value is based on a
relative .comparison of the monitors to each other and not to
Method 10.
II. PROPOSED PLAN
A. Objective
Establish the long-term operational performance (durability/
reliability/accuracy) of CO and H_S monitors when the monitors are
installed and maintained as directed by the instrument manufacturer/
vendor and from this data determine what are reasonable and useful
performance specificaions for those monitors.
65
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B. Duration of Project
The field testing will last approximately or-- year The labora-
tory testing preced v, the field study will Is--; one t three"mcnti-.s
deperui'ng on the problems encountered and the instrument, selected for
evaluation.
C. Site Select? r Criteria
The 00 monitors will ;.<- installed at a fluid cat cracker and the
H_S monitors will be Installed on a fuel gas feed line preferably
equipped with an amine treater for removal of HpS. The otual
selection of the test site(s) will be made using the following
criteria:
1. Attitude of plant management toward program.
2. Accessibility of site to EPA and EPA contractor
personnel for installation, calibration and
maintenance of equipment.
3. Scheduled plant shut-downs for maintenance,
production changes, etc.
4. Availability of a room or trailer that is suitable
for installing continuous monitors, i.e., one that
can be maintained at a constant temperature and
humidity.
5. Availability of a stable, continuous supply of
electrical power.
D. Equipment Procurement
1. Continuous Monitors
The continuous monitors will be selected based primarily on
engineering judgment about their technical reliability and durability,
maintenance requirements, data recording requirements, and avail-
ability of spare parts. Specific criteria for monitor selection
include the following:
a) Willingness of monitor vendor to cooperate with EPA,
e.g., supply the monitoring system requested
including all pre-delivery instrument check-outs
requested.
b) Cost of the monitoring system to the government in
relation to other monitors with similar operating
principles.
c) Delivery time involved in obtaining the monitor.
66
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d) Anticipated cost of maintenance, calibration and
repair of the instrument including .. ^liability of
spare parts, r-,se of on-site rep. .r and availability.
of service personnel for major equipment repair.
e) Sampling conditions required by t^e monitor, i.e.,
temperature, stack gas charact- , humidity, flow
rate, etc . and availability of a suitable sample
conditioning system for obtaining the required
sampling conditions.
f) Ex 1. ten- ~f a similar system on other petroleum re-
fir,cri».-r and the demonstrated performance of the
system.
g) Availability and cost of training EPA contractor per-
sonnel in the operation and mai' tenance of the moni-
toring system.
2. Stack Gas to Monitor Conditioning System
The actual sampling system required to bring the stack gas to the
monitors cannot be determined until the field site(s) and the candi-
date monitors are selected. If a commercially-available system exists
that can be obtained at reasonable cost, such a system will be bought.
However, if necessary, a site-specific sample conditioning system will
be designed and installed by EPA. The system installed will meet or
exceed requirements of every monitor that will be used in the evalua-
tion.
3- Data Recording System
It is anticipated that strip chart recorders will be used to
record all data generated by the monitors. Data loggers and magnetic
tapes will likely not be used since these devices have not demon-
strated long-term operational stability. Similarly, manual calibra-
tion and span checks will be an integral part of the program rather
than relying simply on automatic controllers.
E. Trailer for Housing the Monitors
Monitors require a well-controlled environment for operational
stability. A trailer or similar facility that has temperature and
humidity controls will be used to house the monitors.
F. Determination of Performance Specifications
and Operational Characteristics
The performance of the CO monitors will be compared to the ten-
tative performance specifications now being advanced by QAQPS as
Performance Specification M. The performance of H_S monitors will be
compared to the most recent specifications for SOp and NO., monitors.
67
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Relative accuracy performance tests for CO will be conducted using L'PA
Method 10 unless ESRL is able to supply a wet chhemical test method
for CO. The relative accur / tests for HpS will be conducted using
EPA Method 11. Initially, t number of sample specified in perfor-
mance Method 2 for S0_ wi:, be used for the H_S and CO relati.i
accuracy tests. .in checks ind drift checks wil" ^-- done daily using
calibration gas mixtures that correspond to 01, 2;». /"!?. 751 and 100%
of span. However, not all span gases will be used everyday.
Described below is the tentative schedule for these tests. This
scheJjle may change based on final selection of monitors and test
sites:
Parameter
Relative Accuracy Test
Zero/Span Checks
0, 50%. 100% span check
0. 25%. 50%. 75%. 100% span check
Response Time/Noise Check
Interference of other gases
Time Interval
1 week
1. 2. 4. 8. 12 months
daily
weekly
weekly
monthly
G. Tentative Schedule for Accomplishment of Study
Task
Obtain permission to presurvey
tentative sites
Complete site visits and select
test sites
Order monitors/sampling
systemsi etc.
Procure necessary supplies for
reference method tests
Complete laboratory check-out
of monitors
Install/check-out monitors
Complete field studies
Completion Date
May 15. 1979
June 15. 1979
July 15. 1981
August 15. 1979
November 15, 1979
January 15, 1980
January 15, 1981
68
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III. SPECIAL NOTES
A. Each monitor will be subjected to whatever lab "' ,-t.s are
necessary to determine if it will work in a field '--' .ation.
These lab tests may be done by the vendor before shipping the
equipment to the EPA contractor.
B. Tentatively, we plan to have the persor or persons res-
ponsible for maintaining the monitors receive monitor-specific
training from the instrument vendor either on-site or at the
vendor's facility.
C. Based on cost and anticipated delivery time, spares uf
those components most likely to fail (phototubes, scrubber
columns, switches) will be stored at the test site.
D. If possible, two identical instruments may be operated
at the site to yield an estimate of instrument precision. The
method of standard add .ms may also be employed on occasion to
check the reliability of the monitors. In this case, a calibra-
tion gas would be injected into the sample stream to see if the
expected increase in response was obtained.
69
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APPENDIX C
VENDORS RESPONSE TO LETT!
.; EPA
NECAtlvT
0 USFONSE
icspON&r. co H,S PROPOSED INSTXUKENT COST/OPERATINC miNCirut
Applied Automation. Ine
Pawhuaka Road
artlesvUle. OK 74004
CO: OpH -ram 102 CO: S9795/CC/F1D
H,S: Optiinrosi (02 H,S: SD.OOO/CC/FPD
Astro Ecology Corp.
P. 0. »o» 58159
Houston. TX 77058
Bacharach Instruments
2300 Leghorn Street"
Mountain View. CA 9404]
la Ml Ine Industrie*
P. 0. to* 648
Lyona. CO M>40
teckaan Inatruiwnt*. Inc.
Proce** Inatrunenta Dtvlaton
2SOO Harbor llvd.
Fullerton. CA 92634
endix Corporation
Envlronaencal . Proceca
Inacruncnts i;i-Lsion
P. 0. Drawer 831
Lewlaburi. WV 24901
Environmental and Procesa
Analyzer Market Development
CEA Inatruawnts. Inc.
IS Charlea Screet
Westwood. NJ 07675
Calibrated In*tr\»enti. Inc.
731 Sav Hill River Road
Ardaley. NY 10502
Contravci-Cocrz Corp.
610 Epiilon Drive
Pittaburgh, PA 15238
Control Inatri»enca Corp-
I8Paaaaic Avenue
fairfield. NJ 07006
Dictaphone Ca* Detection Products
Audio/Electronics Division
475 Ellis Street
Mountain View. CA 9404)
Dlfllab. Inc.
237 Putnaa Avenue
Cartridge. MA 02139
[.I. DuPont DeNcBours 6 Co.
1007 Market Street
Wilmington. DE 19709
Enerxetlcs Science. Inc.
15 Eucutlve IIvd.
EiBslord. MY 10523
XX CO: XXX)
CO: P 1030*
H»S: P 1030A
CO: 865-14
H,S: 9S1
CO: 8903
H,S; 7770
CO: S2800/IR
CO: S4500/CC/TC
HjS: S380O/CC/FFD
co: 54200/mm
HjS: S9000/Cheallumlneacence
CO: S6000/SDIR
HaS: 59710/CC/FFD
XX
XX CO: instru. not specified 1R (cost not specified)
XX
H,S: 400
XX CO: Ecolyier 3107
H,S: 58800/fV
CO: S2IOO/electroch
70
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APPENDIX C
VENT-RS RESPONSE TO LETTER FROM EPA
NEGATIVE
o RESPONSE
RESPONSE CO H,S
PROPOSED INSTRUMENT
COST/OPERATING PRINCiriE
Dynat
EIWI-
To«r«t I
llu* -..
. ^roduct* Dlv.
-r aoad
» 19422
XX
Ecole>-' B^ari. Inc.
92V lndeoe~.*--nce Ave.
Chatavortn. 'A 91311
Ethyl Interteeh Corp.
19 Roszel Road
Princeton. NJ 085to
xx
Hewlett-Packard
Scientific Instruments Div.
1601 California Avenue
Palo Alto. CA 94304
Horlba Instruments. Inc.
1021 Durvea Ave.
Irvine. CA 92714
Houston Atlas. Inc.
9441 Baythorne Drive
Houston. TX 77041
Infrared Industries
Western Division
P 0. Box 989
Santa Barbara. CA 93102
Laiar Research Lab*. Inc.
509 N. Fairfax Ave.
Los Angeles. CA 90036
Leeds 4 Northrup Company
juaHieytovn Pike
North Wales. PA 194M
XX
XX
H,S: B25R-I02N
H,S: 722R-I02
XX CO: 703
HjS: $7200/Pb Ac
HjS: S12.089/PbAc«
CO: 51995/NOIR
Nrlor Laboratories. Inc.
671} Electronic Drive
N. Springfield. VA 221S1
Mine Safety Appliance Co.
600 Penn Center llvd.
Pittsburgh. PA 15235
Monitor Labs. Inc.
10180 Scripps Ranch llvd.
San Diego. CA 92131
Process Analyzers. Inc.
1101 State Road
Irlnctton, NJ MS40
.111 Con Roy Company
Flou Control Dlv.
20} Ivyland Road
Ivy land. FA 11974
Tsledyne. Inc.
Analytical Instruments Dlv.
333 k. mission Drive
San Gabriel. CA 91776
Therae Electron Corp.
Environmental Instruawnts Dlv.
101 South Street
Hopklnton, HA 01741
XX CO: Lira 202
CO: Luft detector
HjS: Not specified
CO: 26-222-4
H,S. 32-230
CO: S6400/NDIR
CO: S7000/SDIR
H,S: CC/FPD
CO: S6100/CC/TC
H,S: $9
CO: 9300
M,S: til OKCO-20X
CO: S9100/ND1R
H,S: S&700/LV
XX
71
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APPENDIX C
VENDORS RESPONSE TO LETTER FROM EPA
MECAT1VZ
NO RESPONSE
USPGttSE CO H,S PIOPOSED W
COST/OFEKAT1SJ ?'11C1PLE
Tracor. Inc.
XnstruMnt Plvlsion
*»0 Tracer Lan«
Austin, rx 78721
U*it«rn «e-
1113 -
Culgary Alta
ch and
.cd.
... NE
Del Mar Scientific
P. 0. lo* 416
Addiion. IX 75001
Anarad. Inc.
P. O. loi 1160
Santa Sarbar*. CA 91103
XX
XX
H,S: OM-U»«
XX CO: A* 501R
H,S: S4700/PbAc
CO: S3 500 /SB IX
pro|>o*«d. hue when told oroerln| I>«1 Mar they offered the 8:iR-102N.
72
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APPENDIX 0
FCC EMISSIONS GAS SAMPLE CONDITIONING SYSTEM
The stack gas was conditioned at the stack to r<.,ve particulste,
acid mist and moisture. The gas conditioning .v ---- was housed in a
metal case 55 cm ty 76 cm by 33 cm. The system ,.-;0ure D-1) consisted
of the following ps-ts:
1. Probe. SS 202, length 130 cm, OD 5.1 cm. ID M.9U cm,
slots 2 to 4 cm wide cut in the 40 cm nearest the tip
and covered with Balston Type 20/80-A microfiber filter
(5.1 cm ID by 45 cm long), glass wool plug in probe tip;
and steel plate welded 5 cm from the end to attach probe
to port flange and probe extension (Figure D2).
2. Probe Extension. Aluminum pipe, 28 cm long, 10 cm OD,
one end welded to aluminum plate (to attach extension tc
probe) and other end externally threaded to accommodate
pipe cap. Each side contained a piece of aluminum
tubing 2.5 cm OD by 8 cm long to allow sample to pass
from probe into the gas conditioning system and to allow
a stack sample to be withdrawn into a Tedlar bag. The
bottom of the extension contained a piece of aluminum
tubing 1.6 cm OD by 5 cm long for attaching a 60 cm
U-shaped drain. This drain continuously removed
condensate from the probe extension while maintaining a
water seal to prevent ambient air from entering the
system.
3. Balston 20/80-A Filter Housing (35304) with Type 200-80
Grade D and Type 200-35 SS filter support core filter.
Gas passed from inside to outside to coalesce water and
remove small particulates. A U-trap was attached to the
bottom to allow continual draining of the condensate.
4. Balston 97S6 Filter Housing (SS316) with 05Q-05CH micro-
fiber filters (1.2 cm ID by 3.1 cm long). One of these
filters was added to the system December 5, 1980, to
reduce plugging of the Perma Pure dryer; the second was
added January 9, 1961.
5. Perma Pure Model PD-1000-21S (200 tubes, 60 cm long).
Two connected in series to remove moisture. A pressure
regulator was used to maintain dryer purge air at a flow
of 17 L/min at 2 to 3 psi.
73
-------
6. Pump. ADI Model 19320-T dual-stage (with Carpenter 20
heads to reduce corrosion), T?fIon-coated diaphrara and
Viton valve gask r ,nd discs. The single-stage pump.
used originally would be adequate for most systems.
7. Tubing. SS 316 between probe exter on and Balst n 97S6
filter, polypropylene betwo 97S6 filter and j. tip.
8. Sample Lir.p. 20C m long. 0.95 cm ID by 1.2 cm OD. black
nylon, unheated.
9. Bals^on 20/80-A Filter Housing with Type 20/80-A Grade
D, microfiber filter. Located immediately in front of
the trailer to remove fine particulate.
The overall performance of the gas conditioning system was very
good. Problems and changes that occurred between February 11, 1980
and April 28, 1901, are summarized in Table D-1. In general, the
following comments are noted:
1. Polypropylene tubing was found to be superior to
stainless steel tubing. The latter reacted with the
stack gas to yield a fine particulate that collected at
bends and elbows in the conditioning system.
2. The Balston 20/80-A filter was difficult to disassemble
in the field due to its large diameter and the lack of
large wrenches.
3. The U-shaped drains worked well, but care should be
taken to prevent freezing; either by wrapping the drain
with heating tape or by using heat radiating from the
stack.
1. From. February 18, 1981. to April 28, 1981, the system
worked without failure or maintenance at a sampling rate
of 5 to 8 L/min. When disassembled on April 28, 1981,
the Perma Pure dryer inlet contained no particulate, the
Balston 20/80-A filters were unbroken, the pump inlet
diaphram contained a reddish syruplike liquid (pH less
than one) that absorbed water rapidly upon exposure to
the ambient air. An anion analysis showed that the only
anion present was sulfate.
5. The system described was constructed to provide a sample
flow rate of 6 to 15 L/min to the trailer with a minimum
system response time. For most applications, a flow
rate of 1 L/min would be sufficient; thus one PD-750-21
inch (100-tube) Perma Pure dryer might be adequate for
74
-------
most applications. This would result In a considerable
savings. In addition, the probe / r.-j;r: and th
Balston 20/80-A fi ;r in the 38~,~le case could b«-
replaced with smaller unl*- ;thout -i.ersely affecting
the sample conditioning systen. Proc/t- filter integrity
was maintained as long as the slotted side of the probe
was facing downstream. When the probe was rotated 90
so that only half the slotted side of the probe was
facing downstream, a hole about one cm in diameter
formed in the fil*.°'- at a poi-.t about 35 cm from the
tip. A glass wooi plug in the probe also helped xeep
the probe clear.
75
-------
IT
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76
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FIGURE D-2. PROBE. PROBE EXTENSION AND BALSTON 20/80-A FILTER.
77
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79
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APPENDIX E
MANUAL METHOD FOR "EAT.'HNG
CARBON MONOXTDE IN RrT.'-INERY GASES
1. PRINCIPL AND APPLICABILITY
1.1 Principle
An integrated sample is extracted from the gas stream, passed
through hydrogen peroxide and alkaline permanganate solutions and
collected in a Tedlar bag. The carbon monoxide (CO) concentration in
the sample is measured spectrophotometrically using the reaction of CO
with a palladium chloride/leuco crystal violet/potassium iodate
solution.
1.2 Applicability
This method is applicable for determining CO emissions from
stationary sources.
2. RANGE AND SENSITIVITY
2.1 Range. As written, the method applies to gas samples that
contain 20 to 1000 ppm CO. Samples containing in excess of 1000 ppm
CO can be analyzed by reducing either the gas volume or the shaking
time. Samples containing less than 20 ppm can be analyzed by
increasing the volume of sample reacted with the palladium
chloride/leuco crystal violet/potassium iodate solution or by
increasing the shaking time or frequency. However, if such changes
are made in the procedure, the linearity of the absorption curve must
be checked under these conditions.
2.2 Sensitivity. Sensitivity depends on shaking time, shaking
frequency, gas volume and shape of reaction vessel and cannot be
specified absolutely. As written, the sensitivity of the method is
approximately 10 ppm CO.
2.3 Interfering Agents. Sulfur oxides, nitric oxide, and other acid
gases which interfere with the reaction, are removed from the gas
sample during sample collection. These gases are removed by passing
the sampled gas through a 4 percent potassium permangate/5-percent
sodium hydroxide solution. Carbon dioxide does not interfere with the
reaction, but, because it Is removed by the scrubbing solution, its
concentration must be measured and an appropriate volume correction
made.
80
-------
4. PRECISION, ACCURACY AND STABILITY
4.1 Precision. The estimated intralaboratory standard deviation of
the methoJ is 2.5 percent of the mean for gas -a-iples analyzed in
triplicate. This estimate, which applies to th Concentration range
20 to 1000 ppm, was determined from 22 sa- os collected at a
petroleum refinery. The interlabortory precision has not been
established.
4.2 Accuracy. On the average, the manual method results were biased
4 percent high for 22 sample > analyzed by an NDIR calibrated with NBS
standards. The manual methc.d was biased 5 percent high when used to
analyze certified calibration g£3 mixtures that contained SO., NO.
C0?, and 100 to 500 ppm CO in nitrogen.
1.3 Stability. The individual components of the colorimetric reagent
are stable for at least one month, but the colorimetric reagent must
be used within 3 hours after preparation to avoid excessive blank
correction. For optimum accuracy the samples must be reacted and
analyzed no later than 3 hours after the colorimetric reagent has been
prepared.
5. APPARATUS
5.1 Sampling (Figure E-1)
5.1.1 Probe. Stainless steel, sheathed Pyrex glass or equiva-
lent, equipped with a glass wool plug to remove particulate matter.
5.1.2 Impinger. Three Greenburg-Smith impingers connected in
series with leak-free connections.
5.1.3 Pump. Leak-free pump. Metal Bellows Model 110 or equiva-
lent with stainless steel and Teflon parts to yield a flow rate of 0.2
to 0.4 L/min.
5.1.4 Surge Tank. Installed between the pump and the rate meter
to eliminate the pulsation effect of the pump on the rate meter.
5.1,5 Rate Meter. Calibrated rotameter, or equivalent, to
measure flow rates between 0 to 0.4 L/min.
5.1.6 Flexible Bag. Tedlar, or equivalent, with a capacity of 10
liters. Bag must be leak-free.
5.1.7 Valve. Needle valve, or equivalent, to adjust flow rate.
5.1.8 Fyrite Analyzer, or equivalent, to measure CO- concentra-
tion to within +0.5 percent accuracy.
81
-------
5.2 Analytical
5.2.1 Spectrophotometer. Single or double beam to measure
absorbance at 589 rm. Slit width should not exceed 20 nm.
5.2.2 Vacuum Gauge. U-tube manometer, 1 meter (36 in.), with
1-nm divisions, or other gauge capable of measuring pressure to within
±2.5 mm Hg (0.10) in. Hg).
5.2.3 Pump. Capable of evacuating the gas reaction bulb to a
pressure equal to or less than 75 mm Hg (3 in. Hg) absolute, equipped
with coarse and fine flow control valves.
5.2.4 Barometer. Mercury, aneroid, or other barometer capable of
measuring atmospheric pressure to within 2.5 mm Hg (0.1 in Hg). In
many cases, the barometric reading may be obtained from a nearby
national weather service station, in which case the station value
(which is the absolute barometric pressure) must be requested. An
adjustment for elevation differences between the weather station and
sampling point must then be made at a rate of minius 2.5 mm Hg (0.1
in. Hg) per 30 m (100 ft) elevation increase, or vice versa for
elevation decrease.
5.2.5 Reaction Bulbs. Pyrex glass, 100-125 mL with Teflon
stopcock, leak-free at 650 mm Hg. Designed so that 10 mL of the
colorimetric reagent can be added and removed easily and accurately
(Figure E-2). Commercially available gas sample bulbs such as Supelco
12-2161 and Alltech 17012 can also be used.
5.2.6 Volumetric Pipettes. Class A, 4 mL and 10 mL and 1 mL
graduated pipette.
5.2.7 Volumetric Flasks. 100 mL
5.2.8 Graduate Cylinder. 1000 mL.
5.2.9 Shaker Table. Reciprocating-stroke type such as Eberback
Corp. Model 6015. A rocking arm or rotary-motion type shaker may also
be used. The shaker must be large enough to accommodate at least six
gas sample bulbs simultaneously. It may be necessary to construct a
table top extrusion for most commercial shakers to provide sufficient
space for six bulbs (Figure E-3).
5.2.10 Spectrophotometer cells. 1 cm pathlength.
82
-------
6.0 REAGENTS
6.1 Sampling
*
6.1.1 Alkaline Perman£ --ite Solution. Prepare by dissolving 40
grams of ACS reagent grade sodium hydroxide and 50 grams of ACS
rea&ent grade potassium permanganate in 1 liter of c ..tilleJ water.
This is sufficient for removing NO and S02 from 50 liters of gas
containing 15% CO..
6.2 Analysis
6.2.1 Stock Solutions
6.2.1.1 Potassium lodate. ACS reagent grade, or equivalent.
6.2.1.2 Sodium Chloride. ACS reagent grade, or equivalent.
6.2.1.3 Palladium Chloride. ACS reagent grade, or
equivalent.
6.2.1.4 Sodium Honohydrogen Phosphate Heptahydrate
(Na HPOjj.TH 0). ACS reagent grade, or equivalent.
6.2.1.5 Leuco Crystal Violet (U.M'.U" methylidynetris (N.N-
dimethylaniline)). Eastman Kodak Company Stock No. 33651.
6.2.1.6 Phosphoric Acid (85X). ACS reagent grade, or
equivalent.
6.2.2 Working Solutions
6.2.2.1 Sodium Monohydrogen Phosphate (0.001M). Dissolve
2.68 grams in 100 mL of distilled, deionized water. This solution is
stable indefinitely.
6.2.2.2 Sodium Tetrachloropalladate(II) Solution (0.005M).
Dissolve 0.0887 grams of palladium chloride and 0.0595 grams of sodium
chloride in 50 mL distilled, deionized water and dilute to 100 mL.
This solution, is stable for at least one month. If a brown precipate
forms it can be dissolved by adding a few crystals of sodium chloride.
6.2.2.3 Leuco Crystal Violet Solution. Dissolve 0.0256
grams leuco crystal violet in 80 mL water containing 10 mL of 85X
phosphoric acid and dilute to 100 mL. Tnii solution is stable for at
least one month.
6.2.2.4 Potassium lodate Solution (0.1M). Dissolve 2.14
grims of potassium iodate in 100 mL of distilled deionized water.
This solution is stable indefinitely.
83
-------
6.2.2.5 Colorimetric Solution. Pipet 4.0 mL each of potas-
sium iodate solution (6.2.2.4), leuco crystal violet solutior
(6.2.2.3) and sodium tetrachloropalladat (II) solution (6.2.2.2) -int'
a 100 mL volumetric flask. Plpet 0.6 m!. sodium monohydrogen p ho spa to
solution (6.2.2.1) into the r isk and dilute to volume. This solution
should be used within 3 hours of preparation to minimize the contribu-
tion of the blank and the -ample absorbance. Thi:> is sufficient
volume to Analyze three stac^ as s-.-nples in triplicate.
6.2.2.6 Standard C.i Mixtures. Traceable to NBS standards
and containing between 100 an: 1000 ppm CO in nitrogen. The calibra-
tion gases shall be certified by the manufacturer to be within +_ 2
percent of the specified concentration.
7.0 PROCEDURE
7.1 Sampling. Evacuate the Tedlar bag completely using a vacuum
pump. Assemble the apparatus as shown in Figure E-1. Loosely pack
glass wool in the tip of the probe. Place 100 mL alkaline
permanganate solution (6.2.1) in the first two impingers and 250 mL in
the third. Connect the pump to the third impinger and follow this
with the surge tank and the rate meter. Do not connect the Tedlar bag
to the system at this time.
Leak-check the sampling system by plugging the probe inlet and
observing the rate meter for flow. If flow is indicated on the rate
meter, do not proceed further until the leak is found and corrected.
Insert the probe into the stack and draw sample through the system at
300 _* 50 mL/rain for 5 minutes. Connect the evacuated Tedlar bag to
the system, record the time and sample for 30 minutes, or until the
Tedlar bag is nearly full. Record the sampling time, the barometric
pressure and the ambient temperature. Purge the system as above
immediately before each sample.
The sampling system above is adequate for removing sulfur and
nitrogen oxides from 50 liters of stack gas when the concentration of
each is less than 1,000 ppm and the CO- concentration is less than
15%. The samples in the Tedlar bag should be stable for at least one
month, if the bag is leak-free.
7.2 Ancillary Methods
Measure the CO. content in the stack to the nearest 0.5S each
time a CO bag sample is collected. A grab sample analyzed by the
Fyrite analyzer is acceptable.
-------
7.3 Analysis
Assemble the system shown in Figure E-4 and record the informa-
tion required in Table E-l as it is obtained. Pi pet 10.0 mL of the
colorimetric reagent (6.2.2.5) in each gas reaction bulb (5.2.5) and
attach the bulos to the system. Open the stopcocks on the gas bulbs
but leave the valve on the Tedlar bag closed. Turn on the pump, fully
open the coarse-adjust flow valve :>r.d slowly open the fine-adjust
valve until the vacuum is at least obO ran Kg. Now close the coarse
adjust valve and observe the tr.ancneter to be certain that the system
is leak-free. Wait a minimum of two minutes and if the pressure has
decreased less than 1 mrc. proceed as described below. If a leak is
present, find and correct it before proceeding further.
Record the vacuum pressure to the nearest 0.1 mm Hg and close off
the gas bulb stopcock. Open the Tedlar bag valve and allow the system
to come to atmospheric pressure. Close the bag valve, open the pun-
coarse adjust valve and evacuate the system again. Repeat this
fill/excavation procedure at least twice and then close off 'the pump
coarse adjust valve, open the Tedlar bag valve and let the systen fill
to atmospheric pressure. Open the stopcocks on the gas bulbs and let
the entire system come to atmospheric pressure. Close the gas bulb
stopcocks, remove the bulbs and place them on the shaker table with
their main axis either parallel to or perpendici-1 ar to the plane of
the table top.
Record the room temperature and the barometric pressure (nearest
0.1 mm Hg) after each set of gas bulbs is filled. At least one set of
bulbs from a Tedlar bag containing a known concentration of CO in
nitrogen must be used each time a set of samples is shaken. Improved
accuracy will be obtained if two standards are included each time.
Also, to avoid cross contamination of samples, the bulb filling system
must be purged with ambient air for several minutes between samples.
Shake the samples for 25 minutes if the expected concentration is
less than 600 ppm and for 20 minutes if it is between 600 and 1.000
ppm. Place the contents of each bulb in a labeled test tube or other
suitable vessel.
Measure the absorbance of each sample at 589 nm using water as
the reference; also measure the absorbance of the unreacted
colorimetric reagent used for that set of samples to serve as a
reagent blank. Reject the analysis if the blank absorbance is greater
than 0.1.
The absorbance curve is linear to an absorbance of 1.8. If the
sample absorbance exceeds this, the sample can be diluted with the
colorimetric reagent.
85
-------
The reaction between CO .ir.-J the eol trie solution Is sic-.
For example, unshaken samples :,->-. aside ne hour after fill:
snow no significarr
-------
volume of gas (SA) according to Equation E-1 action 9."') f-r ,r.
sample and determine he avera*;-. 3K f,-_r al- ..uples wil- identical
shaking times. P1 ;. r av* :*,;:» sr, ,-cr > the shaking time^ to
deternine the line. .: r.he at.v.. ;-. . . . ve. Use this data" to
deter-, ine t.r .? shaking time and sample vaiu-.-e jired for sample-
analysis.
8.4.2 Sam pi- Bag-Leak C. ocks
While a bag- leak check = - - .->d -ubsequ-^ ". to - -», it
should also be done before f > c
-------
9.2.2 Calculatl of CO Cone :>-'.ration Bag
9.2.2.1 "' £le Standard . ken with Sampl
Calcu"! ' the CO
ion in ' o bag :sing Equations E-2
and E-3. If -nsate is visi: in *.* Tedl ?ag, calculate BW
using Table E the ternperat . . and barome. pressure in the
rom where the --f ..--is wac Jonc. If condenc is not visible,
caiculat.'? B using the temperature and barometr:'- pressure at the
sampling site.
B
CO
Vapor pressure of water in bag
Bar^netric pressure
'Bag
Ejpm CO in stdl I/
'-'» J L
; Average SA sample
Average SA std
(E-2)
(E-3)
9.2.2.2 Two Sets of Standards Shaken with Samples
Construct a graph of concentration versus the average SA for
each standard forcing the curve through the origin. Determine the CO
concentration in each Tedlar bag stack sample using the average SA for
each sample and correct for the amount of moisture present (B ).
9.2.3 Calculation of Stack CO (dry basis)
Calculate the CO in the stack using Equation E-4.
COStack - C°Bag
(E-4)
10.0 BIBLIOGRAPHY
Lambert, J.L., and R. E. Weins. Induced Colorimetric
Method for Carbon Monoxide. Anal. Chera., 46: 929-930,
197«.
88
-------
TABLE E-1. MOISTURE CORRECTION
TEHPERATUP" VAPOR PRESURE
(°C) H20 (ran Hg)
4
6
8
10
12
14
16
18
20
22
24
26
28
30
6.1
7.0
8.0
9.2
10.5
12.0
13.6
15.5
17.5
19.8
22.4
25.2
28.3
31.8
89
-------
I
CO
s
u
w
90
-------
(DIMENSIONS IN cm)
(.9
3.1
FIGURE E-2. GAS REACTION BULB (0.1 liter)
. 91
-------
FIGURE E-3. ADAPTOR FOR HOLDING GAS BULBS ON SHAKER TABLE
92
-------
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-------
APPENDIX F
INSTRUMENT EVALUATION HISTORY
1/4/80
1/22/80
2/2/80
2/1/80
3/10/80
3/31/80
4/2/80
4/3/80
4/10/80
4/16-4/17/80
4/21/80
4/25/80
6/9/80
7/3/80
9/18/80
11/10-11/12/80
ECOLYZER 3107
10/18/79
4/16-4/17/80
4/21/80
4/27/80
4/28/80
APPLIED AUTOMATION OPTICHROM 102
Instrument received with no instruction
manual.
Instruction manual received, started wiring
instrument.
Power supply failed.
New power supply failed.
Inccr-ect output found (overloaded). Power
supply failed.
Serviceman from Applied Automation arrived to
repair instrument.
Instrument repaired, power supply, output
board and temperature controller replaced.
Output is negative.
Output problem fixed by reversing wiring to
output board and by moving a resistor on it to
another position.
Transported to refinery in trailer.
Instrument turned back on.
Fuse blew in heater circuit.
Zero response varying badly.
Negative peak before CO peak on chronatogram
detected. Chromatograms sent to manufacturer
as aid in troubleshooting.
Condensation in FID caused corrosion to inter-
nal parts. Monitor shut off until manufac-
turer's service representative call.
Applied Automation serviceman tried to repair
monitor - was unsuccessful. Monitor shut
down.
Instrument received. Checked out.
blems found in laboratory checkout.
Transported to refinery in trailer.
Instrument turned on.
Model 2949 filter failed. Replaced.
Model 2949 filter failed. Replaced.
No pro-
95
-------
5/3/30
5/60
1/17/81
2/17/81
ANARAD 501-R
10/2/79
4/16-4/17/80
4/21/80
MSA LIRA 202
11/2/80
1/14/80
2/27/80
3/3/80
3/«/80
3/11/80
3/10-4/3/80
Model 29'-; filter failed.
Replaced.
to mf.--:~.or
filter) to
4/15/80
4/16-4/17/80
4/21/80
4/21-5/1/80
Large carbon filter
line (replaces Mod--'.
operation time.
Electrochemical cell goi.v; bad. Span
was unable to sjvin monitor
Mew ele.-r^.t: .;al cell installed,
zeroed and spanned.
Model 2949 filter failure
elect- chemical cell to fail. Monitor
from evaluation.
sample
extend
control
monitor
caused
removed
Instrument received and checked out in labora-
tory without problems.
Transported to refinery in trailer.
Instrument started up. No problems or outages
occurred before testing was completed in
April 1981.
Instrument not operational as received.
Put into operation.
Apparent failure of output board. Output had
worked previously (on PD-206U) but output now
less than 4 mA. Called MSA. New output board
ordered.
New output board arrived, installed. Output
still not correct. MSA suggested checking
output by voltage drop across a resistor.
Output seemed to be okay by this method, but
power supply board failed soon after test.
Ordered new power supply. MSA suggested that
output problem could be solved by installing a
matching circuit between the MSA instrument
and the data logger.
Power supply board arrived.
Electronics expert, R. Burdine, made several
visits to ascertain output problem and built a
circuit to correct problem. His conclusion
was that such a circuit was not needed, but
that output board was bad (again). New board
ordered.
New board arrived, not tested (trailer packed
for moving).
Transported to refinery in trailer.
Instrument started up. Output still bad.
Instrument off. MSA contacted from Auburn.
96
-------
5/1/8C
5/2/80
5/3-5'20
6/3/SO
6/9-6/16/80
9/18/80
TELEDYNE 611 DMCO-20X
2/80
3/13/80
4/16-4/17/80
4/21/80
4/29/80
5/1/80
5/7/80
9/18/80
11/2/80
BENDIX 7770
1/5/80
2/54/80
D. Tiskiewic A MSA came ' i check pro's: -
According to his meter, out-. . was U-20 mA.
Mr. Tiskiewic said r.v--t matching circuit was
ne- i. MSA-Pittsbu .n would fir.-^ and send
one .
Inr.r. ?nent off. :io .. Batching circuif..
Mate.1 :g circuit rec: . ind installc-d Ly
MSA ser iceman.
Lab evaluation completed in field.
Span and zero adjustment not POSE.Die. Com-
plete optical aligr.Ti-*nt restored performance.
Inatrunent ontinut1 to operate normally
through Jt ».'.o remaining part of the evalua-
tion.
Instrument received with no instructions on
how to install or use molecular sieve canis-
ters.
Initial setup and adjustment. Dimensional
instability noted: very sensitive to even tt;e
slightest change of attitude with respect to
horizontal - even microscopic changes signi-
ficant.
Transported to refinery in trailer.
Instrument turned on and interference in fuel
gas noted.
Molecular sieve installed on sample line. No
effect on sample concentration. Impossible to
zero and span instrument.
Molecular sieve removed.
2-hour drift RA Test spoiled by very high
sample concentration. Instrument readout did
not change before, during or after period of
high concentration.
Monitor shut off due to lack of reliable data
caused by interference.
Molecular sieve received from Teledyne. ifhen
installed, no startup was possible because of
optical system failure.
Instrument received.
Connections to gas services made, instrument
started :-.-.-.. Several tube fittings inside
leaked and had to be tightened. Initial
adjustment made (oven temp, flows, etc.).
Rtpro
-------
3/11/80
3/21.30
V 16-1/1 7/80
1/21/80
5/7/80
11/5/80
12/15/80
2/25/81
DEL MAR SCIENTIFIC DM-W
2/10/80
4/16-4/17/80
1/21/80
5/7/80
Interr-'. plumbing r 'ifLed to ^c vpt :eparate
source i -'.-js- valv- . . h-:.-.ter ir. Wher.
instrument was r*-. r od, ovei. ' ».I-T was
inadvertently shcf Causing :ie:ar- orv of
TRIAC in ' -?,ter cor.i.rol circuit. New :RIAC.-=
orde*-
Part:. :.-ed but pr-jved to be wrong. Correct
par?. ^re-1..
Corr--.-r -3rt.; rec^-.ved, installed success-
fully. Instrument restarted.
Trar *.--. to rei'i.iery in trailer.
Ins', --t .ar-ted back up.
2-hou: Jritt. RA Test spoiled due to high H?S.
Instrument system recovered from high H?S in
about 1 hours.
Monitor failure from 2 weeks previous caused
by diaphragm on sample valve. New part
ordered.
Diaphragm replaced. Monitor operating pro-
perly.
Sample valve diaphragm ruptured and repaired.
Instrument operated properly throughout the
remaining field evaluation.
HOUSTON ATLr, 825/102R
12/11/79
1/20/80
1/16-1/17/80
1/21/80
1/23/80
Monitor received and set-up.
Transported to refinery in trailer.
Instrument turned on. Pressure/flow problems
noted. Sensitivity critically dependent on
flow (which varies with pressure and gas
viscosity).
Very high H^S concentration encountered in
fuel gas at 10:00 am. Analyzer did not re-
cover until next day. Instrument operated
properly throughout study, but gas dilution
system was not appropriate for fuel gas
dilution.
Instrument received.
Instrument setup.
Transported to refinery in trailer.
Instrument turned on. Output overloads data
logger. Tape does not advance. Ordered new
output/cycle time board.
New board arrived. No effect. Timer relay
ordered.
Reproduced from
btil «vaiUble cooy.
98
-------
«/;".'89
5/1/6J
5/5/80
5/8/80
5/8/80
9/11/8C
9/18/80
11/2/80
1/6/81
3/31/81
Relay received. No effect.
Abrah -.1 Aspenc of HAI arrived to trouble-
shoot. Did not find problem. Took analyzer
back.
Asperic informed us of wiring mistake to data
logger. Sent instrument back to us.
Instrument arrived with wiring instructions.
Inutrun-:-. t turned on - work::.
Monitor sant to manufacturer for
Monitor returned by manufacturer.
Houston Atlas serviceman found -
to be condensation in vent line.
Dilution system breakdown. Circuit board in-
stalled backwards by contractor personnel.
New part delivered.
Monitor failure due to corrosion in timer.
of drift
PROCESS ANALYZERS INCORPORATED 32-230
12/20/79
1/80-3/80
5/9/80
6/9/80
8/28/80
9/18/80
10/1/80
11/5/80
Instrument received.
Instrument not operational - many circuit
cards exchanged with manufacturer. Instrument
eventually returned for repair.
Monitor returned from manufacturer allowed to
warmup until next site visit.
Monitor broken down during 1-month warmup.
Returned to manufacturer.
Monitor returned to manufacturer.
Monitor returned to field test, 4 to 20 mA
output not functioning.
Monitor stopped operating.
Monitor failure caused by wearout of 10 port
valve. Monitor shut down and removed from
further testing.
99
-------
TECHNICAL REPORT DATA
(Nemx md Imtnttriom a* Ike rrrtne before completing)
RCPOffTNO.
EPA-600/4-82-054
ORD Report
3. RECIPIENT'S ACCESSION NO.
227406
. TITLE AND SUCTITLC
FIELD EVALUATION OF CARBON MONOXIDE AND HYDROGEN
SULFIDE CONTINUOUS EMISSION MONITORS AT AN OIL
REFINERY
I. REPORT DATE
July 1982
I. PERFORMING ORGANIZATION CODE
. AUTHOM4S)
R. E. Lester and B. B. Ferguson (Harmon)
If. J. Mitchell (EPA)
I. PERFORMING ORGANIZATION REPORT NO.
. PERFORMING ORGANIZATION NAME AND ADDRESS
Harmon Engineering and Testing
Box 2247
Auburn Industrial Park
Auburn, AL 35810
1O. PROGRAM ELEMENT NO.
11. CONTRACT/QUANT NO.
68-02-3405
1. SPONSORING AGENCY NAME AND ADDRESS
Environmental Monitoring Systems Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
13. TYPE OF REPORT AND PERIOD COVERED
Final
14. SPONSORING AGENCY CODE
EPA 600/08
». SUPPLEMENTARY NOTES
To be published as an ORD Project Report
6. ABSTRACT
An eleven month field evaluation was done on five hydrogen sulfide and four
carbon monoxide monitors located at an oil refinery. The hydrogen sulfide monitors
sampled a fuel gas feed line and the carbon monoxide monitors sampled the emissions
from a fluid cat cracker (FCC). Two of the four carbon monoxide monitors operated
over the eleven month period and showed good agreement with the leuco crystal violet
(LCV) wet chemical method developed for the purpose of checking monitor accuracy.
The LCV method and the special stack gas conditioning system employed to remove mois-
ture and particulate from the FCC stack gas are also described. The gas conditioning
system operated for 14 months without a major failure. None of the five hydrogen sul-
fide monitors was found acceptable. Two of the five never obtained a valid sample and
the other three did not agree well with the EPA Reference Method 11 during relative
accuracy testing.
7.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
c. COS AT I Field/Group
Stack gas conditioning system
Carbon monoxide monitors
Hydrogen sulfide monitors
Fuel gas feed line
Carbon monoxide wet chemical method
Leuco crystal violet
EPA Method 111
18. DISTRIBUTION STATEMENT
RELEASE TO PUBLIC
19. SECURITY CLASS (Tlia Report)
UNCLASSIFIED
21. NO. OF PAGES
20. SECURITY CLASS (Tliispagel
UNCLASSIFIED
22. PRICE
EPA Farm 2220-1 (R«v. 4-77) PREVIOUS EDITION is OBSOLETE
100
------- |