United States
Environmental Protection
Agency
Industrial Environmental
Research Laboratory
Research Triangle Park NC 27711
Research and Development
EPA-600/S7-84-074 Sept. 1984
&ERA Project Summary
Environmental Assessment of a
Crude-Oil Heater Using Staged
Air Lances for NOX Reduction
R. DeRosier
This report describes emission results
obtained from field tests of a crude-oil
process heater burning a combination
of oil and refinery gas. The heater had
been modified by adding a system for
injecting secondary air to reduce NOx
emissions. One test was conducted
with the staged air system (low-NO.),
and the other, without (baseline). Tests
included continuous monitoring of flue
gas emissions and source assessment
sampling system (SASS) sampling of
the flue gas with subsequent laboratory
analysis of samples utilizing gas chro-
matography (GC), infrared spectrome-
try (IR), gas chromatography/mass
spectrometry (GC/MS), and low reso-
lution mass spectrometry (LRMS) for
organics. Atomic absorption spectro-
metry (AAS) and spark source mass
spectrometry (SSMS) were used for
trace metal analysis. Flue gas concen-
trations of NO* were reduced 30
percent (from 83 to 56 ng/J) with the
staged air system. Total organic emis-
sions dropped from 17.1 to 3.4 mg/
dscm from the baseline to the low-NOx
test, due primarily to a reduction in the
Ci to Ce boiling point range compounds
which constituted most of the organic
emissions. GC/MS analysis identified
11 semivolatile priority pollutant com-
pounds in both tests, most of them
present in higher concentrations during
the baseline test. LRMS analysis sug-
gested the presence of eight compound
categories in the organic emissions
during the baseline test and four
compound categories in the low-NO.
test. Radiometric analysis of the flyash
particulate indicated no measurable
radionuclide emissions. Biological tests
indicated that the sorbent module
extracts from both tests were of
moderate toxicity and moderate-to-
high mutagenicity.
This Project Summary was developed
by EPA's Industrial Environmental
Research Laboratory, Research Triangle
Park, NC, to announce key findings of
the research project that is fully docu-
mented in a separate report of the same
title (see Project Report ordering infor-
mation at back).
Introduction
Advanced forms of combustion modifi-
cations have been developed in recent
years as a way to reduce NO* emissions
without adverse consequences, such as
capacity loss caused by derating the unit.
Staged combustion using air injection
lances is one form of combustion modifi-
cation that is relatively easy to retrofit to
industrial-sized combustion equipment
since it requires relatively minor hard-
ware modification. The report describes
the results of testing a refinery crude-oil
heater fitted with air injection lances. The
unit was tested with and without the
staged combustion system in operation.
The flue gas was analyzed for criteria
pollutants as well as noncriteria organic
and inorganic species.
The crude-oil process heater tested has
a rated maximum firing rate of 16-MW
(55 million Btu/hr) heat input. The heater
uses six John Zink DBA-22 natural-draft
burners that can fire a combination of oil
and gas. The heater had been modified by
adding a system to inject secondary air to
reduce NOX emissions. This system
consists of a fan to supply the air, a
manifold and associated tubing, and 24(4
per burner) variable-height air lances.
The air lances can deliver half of the stoi-
-------
chiometric combustion air; the rest of the
combustion air is delivered through
secondary air registers at the base of the
heater. Air flow through the heater is
controlled by a damper above the convec-
tion section.
Summary
Heater Operation
The test plan called for exhaust gas
emission measurements under both
baseline and low-NOx operation. Table 1
summarizes the heater operating condi-
tions for each test. Originally the tests
were to be conducted while firing a
50/50 mixture (by heat input) of oil and
refinery gas. However, due to clogged oil
guns, only four burners were capable of
firing oil. Thus, as shown in Table 1, the
tests were conducted while firing approx-
imately a 36/64 mixture (by heat input)
of oil and reabsorber gas. The oil compo-
sition changed very little, but the reab-
sorber gas composition varied slightly
between the baseline and low-NOx tests.
Table 1 also shows that, except for the
percentage of excess air supplied, the
heater was operated under very similar
conditions during the two tests. Based on
the Oz concentration in the exhaust gas
and the fuel composition, excess air was
reduced from 22 percent in the baseline
test to 17 percent in the low-NOxtest. The
data indicated no significant change in
heater operation as a result of the change
to the low-NOx configuration.
Table 1. Heater Operating Conditions
Emission Measurements and
Results
The sampling and analysis procedures
used in the tests conformed to a modified
EPA Level 1 protocol for gas streams. Flue
gas was measured at the stack, about 6
stack diameters downstream of the dam-
per. These measurements included:
Continuous monitoring for O2, CO2,
CO, S02, and N0«.
SASS train sampling.
Controlled condensation system
(CCS) for SO2 and SO3.
EPA Method 5 for particulates.
Grab sample for onsite analysis of
Ci-Ce hydrocarbons by GC.
Grab sample for N20 analysis.
Analyzing the filter catch, ashed
XAD-2 resin, and the first impinger
solution for 70 trace elements using
SSMS and for Hg using AAS.
Analyzing the second and third
impinger solutions for Hg, As, and Sb
using AAS.
Extracting the XAD-2 sorbent resin
with methylene chloride, concentra-
ting the extract, then determining the
organic content of the extract in two
boiling point ranges: 100to300°Cby
total chromatographable organics
(TCO) analysis and >300°C by gravi-
metry (Grav).
Further concentrating the extract
and analyzing for the 58 semivolatile
organic priority pollutants by GC/MS.
IR analysis of the SASS filter, XAD-2
extract, and organic module conden-
sate to identify organic functional
groups.
Process rate, J/s (bbl/day)
Reabsorber gas
Flowrate, m3/min (scfm)
Heat input. MW (million Bw/hr)
Fuel oil
Flowrate, kg/min (Ib/min)
Heat input. MW (million Btu/hr)
Temperatures. 9C (°F)
Crude in
Crude out (east)
Crude out (west)
Pressures, kPa (psig)
Crude in (east)
Crude in (west)
Crude out
Burner - oit*
Burner - steam''
Burner - gas"
Gas pressure to heater
Excess air, percent0
"Average of four burners using oil.
"Average of all six burners.
^Calculated from fuel analyses and flue
Baseline
21.5(11,640)
7.1 (251)
8.35 (28.5)
6.59 (14.5)
4.77(16.3)
196 (384)
338 (641)
336 (637)
960 (140)
896 (130)
227 (33)
324 (47)
537 (78)
30 (4.4)
234 (34)
22
gas Oz measurements.
Low /VO,
21.5(11,640)
7.1 (251)
8.13(27.7)
6.55 (14.4)
4.75 (16.2)
196 (384)
339 (642)
339 (642)
960 (14O)
896 (130)
234 (34)
324 (47)
537 (78)
30 (4.3)
241 (35)
17
Direct insertion probe LRMS of the
XAD-2 extract to identify compound
categories present.
Determining the alpha, beta, and
gamma radiometric activity of the
SASS filter.
Level 1 Ames mutagenicity and CHO
cytotoxicity bioassay tests of the
XAD-2 sorbent extract.
Table 2 summarizes exhaust gas emis-
sions measured in the test program.
Emissions are presented in both nano-
grams per Joule heat input (ng/J) and
micrograms per dry standard cubic meter
of flue gas (/ug/dscm). As a measure of
the relative potential significance of the
emissions for further analyses, the
Threshold Limit Value (TLV) for each
species is also noted in Table 2. Only
species emitted at levels exceeding 10
percent of their TLVs are noted in the
table.
Table 3 summarizes organic emission
from the baseline and low-NOx tests. In
both tests, Ci to C6 hydrocarbons accounted
for the largest fraction of organic emis-
sions (95 percent for baseline and 82
percent for low-NOx).
LRMS analyses of the XAD-2 extracts
indicated that the organic emissions
contained several compound categories, A
listed in Table 4 along with their estimated
emission levels. In addition, 11 semivola-
tile organic priority pollutant compounds
were identified by GC/MS analysis of the
XAD-2 extracts. Table 5 lists the com-
pounds and their concentrations mea-
sured during the two tests.
Radionuclide emissions were measured
by determining the alpha, beta, and
gamma radiometric activities of the flyash
particulate samples. In both tests, the ac-
tivities of the particulate samples were
less than or equal to that of the blanks, in-
dicating no significant radionuclide emis-
sions.
Health effects bioassays were per-
formed on the organic sorbent (XAD-2)
module extracts from both tests. The
bioassay tests performed were the Ames
mutagenicity assay and the CHO cytotoxi-
city assay. The results of these tests,
summarized in Table 6, suggest that the
organic matter trapped by the XAD-2
sorbent is of moderate toxicity and
moderate-to-high mutagenicity.
Conclusions
The use of staged air lances decreased
NOX emissions, with no significant
adverse impacts. Particulate and organic
emissions exhibited slight decreases, but
trace element emissions exhibited an m
apparent increase which may be only
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Table 2. Summary of Exhaust Gas Emissions"
Average Emission
Baseline
Low /VOx
ng/J
/jg/dscm ng/J
Occupational
_ Exposure
Guideline ITLV)
ug/dscm fig/m
Criteria Pollutant and
Other Vapor Species"
SO2
/V0» (as NO,)
/VzO
SO3
CO
Paniculate
Gravimetric organic
(Grav)
Total chromatographable
organic (TOO)
Trace Elements
Silver. Ag
Potassium, K"
Sodium, Nab
Phosphorus, P
Nickel, Ni
Copper, Cu
Iron, Fe
Calcium, Cab
128
83
27
2.1
1.19
8.35
0.11
0.11
9.8 x W7
0.030
XI. 24
3.2 x 70"6
>O.0081
0.0020
0.0076
<1.0x 10~*
480.000
308,000
100,000
8,000
4,400
31,000
400
400
0.0036
110
>910
0.012
>3.0
7.4
28
690
33
29
52
190
380
5.000
6.000
-
55.000
-
-
-
10
2.000
2.000
100
100
200
1.000
2,000
'The Oz and COzConcentrations were 4.0 and 12.1 percent, respectively for the baseline test and 3.3
and 11.7 percent for the low-NOi test.
"True value is probably higher; at least one component of the SA SS train showed a sample and blank
concentration higher than the upper quantification limit.
Tabl«3. Summary of Total Organic Emissions
Organic Emissions
Baseline
mg/dscm
Low /VO,
mg/dscm
Volatile organic gases
analyzed in the field by GC:
Ci
cl
C4
Cs
Ce
Total Ci-Ce
Semivolatile organic material
analyzed by TCO:
XAD-2
Organic module condensate
Total C7-Ci6
Nonvolatile organic material
analyzed by Grav:-
Filter
XAD-2
Organic module condensate
Total Ci6+
Total organics
0
3.6
4.8
6.4
1.5
0
16.3
0.36
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Table 4. Summary of LRMS Analyses
Species Category
Intensity
Estimated Flue
Gas Concentration
mg/dscm
Baseline: TOO + Grav = 0.76 mg/dscm
Ethers
Carboxylic acids
Heterocyclic sulfur
compounds
Alkyl halides
Alcohols
Nitrites
Aromatic hydrocarbons
Heterocyclic nitrogen
compounds
Total
Low NO* TOO + Grav = 0.35 mg/dscm
Aliphatic hydrocarbons
Amines
Carboxylic acids
Aromatic hydrocarbons
Total
100
100
100
10
10
10
10
10
350
100
100
10
10
220
0.22
0.22
0.22
0.02
0.02
0.02
0.02
0.02
0.76
0.16
0.16
0.02
0.02
0.36
Table 5. Results of GC/MS A nalyses
Species
Phenol
Naphthalene
1 ,3-dichlorobenzene
1 , 4-dichlorobenzene
1 ,2-dichlorobenzene
Nitrobenzene
2-nitrophenol
Diphenylamine
1 ,2-diphenylhydrazine
(as azobenzene)
Phenanthrene
2, 6-dinitrotoluene
Other polynuclears
/jg/dscm
1.0
<0.04
0.08
0.04
0.1
0.2
<0.2
0 1
1.4
1.2
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R. DeRosier is with Acurex Corporation, Mountain View, CA 94039.
Robert E. Hall is the EPA Project Officer (see below).
The complete report consists of two volumes, entitled "Environmental Assess-
ment of a Crude-Oil Heater Using Staged Air Lances for NO* Control:"
"Volumel. Technical Results," (Order No. PB 84-223031; Cost: $13.00)
"Volume II. Data Supplement," (Order No. PB 84-223 049; Cost: $22.00)
The above reports will be available only from: (cost subject to change)
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Industrial Environmental Research Laboratory
U.S. Environmental Protection Agency
Research Triangle Park, NC 2771-1
United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
Official Business
Penalty for Private Use $300
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