DAQ-2025-001211

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BigWebttsit>333 W. Center Street. North Salt Lake Utah 84054.80t.296.7700. www.bigwestoil.com
January 30,2025
CERTIFIED MAIL
RETTTRN RECEIPT NO. 9s89 0710 s270 2348 4973 34
Bryce Bird, Director
Division of Air Quality
Utah Department of Environmental Quality
P.O. Box 144820
Salt Lake city, Utah 84114-4820
RE: 40 CFR 63 Subpart UUU Semiannual Report: July l, 2024, to December 31,2024
Dear Mr. Bird,
As required under 40 CFR Subpart lJ[.fU, $63.1575, Big West Oil LLC (BWO) hereby submits its
Semiannual Report for the 2d half of 2024 (July 1 - December 3l ).
Should any questions arise regarding this report or the data submitted, please feel free to contact Brady
Miller at [phone] or by email at [e-mail].
Certifi cation Statement:
I certify that this information was prepared under my direction or supervision in accordance with a system
designed to assure that qualified personnel properly gather and evaluate the information submitted. Based
on my directions and my inquiry of the person(s) who manage the system, or the person(s) directly
responsible for gathering the information, the information submitted is, to the best of my knowledge and
belief, true, accurate, and complete.
Ar*@4l"llb
Alec Klinghoffer 0Refinery Manager
,rr,ll"t *
CC: CERTIFIED MAIL
RETURN RECEIPT NO. 9589 0710 s270 2348 4973 4t
. Director, Air and Toxics Technical Enforcement Program
Office of Enforcement, Compliance and Environmental Justice
Mail Code 8ENF-AT
1595 Wynkoop Street
Denver, CO 80202-1129
Electronic copy to:
Mr. Jeremy Marsigli - Utah DAQ
B-2-10122
Catalytic Reforming Unit (CRU)
The CRU converts low-octane straight-run naphtha into a high-octane gasoline blendstock (reformate).
The CRU consists of three catalytic reactors that increase the octane of the stream through a
dehydrogenation process. Following the series of reactors, catalyst is collected for regeneration, which
involves a rechlorination step that creates the potential for hydrochloric acid (HCl) emissions. The CRU
process unit operated for 4,370.3 hours in the reporting period.
BWO operates a continuous CRU. Therefore, as specified in $63.1567(a)(l) and Item 2 of Table 22 to
Subpart lJ[rU, BWO must meet inorganic HAP emission limits by reducing emissions of HCI by 97%by
weight or to a concentration of 10 ppmv (dry basis), corrected to 3%o Oz. This requirement is met during
coke bum-off and catalyst rejuvenation by venting the process gases to a wet gas scrubber. As stated in
Item I of Table 23 to Subpart [rUU, facilities using a wet scrubber as a control device are required to
maintain the daily average pH of the water exiting the scrubber and the daily average liquid-to-gas ratio
above the limits established during the performance test, which BWO performed in April 2005.
Wet Gas Scrubber: Effluent pH
There were no deviations from the WGS effluent pH daily average operating limit of 5.54 pH units on a
daily basis during the reporting period. In accordance with $63.1575(d)(3), there were no monitoring
downtime events for this monitoring system.
Wet Gas Scrubber: Liquid-to-Gas Ratio
There were no deviations from the liquid+o-gas ratio daily average limit of 0.29 gpm/IvISCFD on a daily
average basis during the reporting period. In accordance with $63.1575(d)(3), there were no monitoring
downtime events for this monitoring system.
Sulfur Recovery Unit (SRI-D
BWO operates a Claus SRU. The SRU processes the overhead gases from the Sour Water Stripper and
the mixture of acid gas from the Amine Unit. These gases are charged in a thermal reactor and a series of
three catalytic reactors to convert the HzS into elemental sulfur. The gases produced in the catalytic
reactor are sent to the SRU Tail Gas Incinerator, where the small amount of remaining HzS and other
reduced sulfur species are converted to SOz present in the process flue gas. A continuous emissions
monitoring system (CEMS) monitors the Oz within the incinerator stack and a continuous parameter
monitoring system (CPMS) continuously monitors the temperature of the incinerator firebox to verify
complete combustion of the reduced sulfur species. The SRU operated for 4,416 hours in the reporting
period.
The SRU at BWO is not subject to either of the New Source Performance Standards (NSPS) for sulfur
oxides at 40 CFR 60 Subpart J or Ja. To comply with 40 CFR 63 Subpart UUU HAP emission limits,
BWO complies with the Total Reduced Sulfur (TRS) limit (Option 2) as specified in $63.1568(aXlXii)
and Item 3 of Table 29 to Subpart UUU. This election requires that BWO maintain emissions of TRS
compounds expressed as an equivalent SOz concentration at or below 300 ppmv on a dry basis at 0o/o Oz.
This emission limit is complied with by maintaining the daily average combustion zone temperature of
the incinerator and the daily average 02 concentration in the vent stream at or above the limits established
during June 2005 performance testing.
SRU Incinerator Combustion Zone Temperature
There were no deviations from the combustion zone minimum temperature operating limit of 1 166oF on a
daily block average. In accordance with $63.1575(d), there were no monitoring downtime events for this
monitoring system.
SRU Incinerator Exhaust O: Concentration
There were no deviations from the vent stream minimum 02 concentration operating limit of 3.5% (dry
basis) on a daily block average.
Incinerator Alternative Standard: Ot Concentration and Temperature
Per $63.1568(a)(4)(iii), BWO may alternatively comply with 40 CFR 63 Subpart UUU during periods of
startup and shutdown by maintaining the hourly average firebox temperature of the incinerator at or above
1200'F and the hourly average outlet Oz concentration at or above 2% (dry basis). During the current
reporting period, the SRU complied with the default combustion zone temperature and exhaust Oz limits;
therefore, the alternative standards for stack 02 concentration and firebox temperature were not
utilized. There were no deviations from the standard.
Millisecond Catalytic Cracking Unit (MSCC)
The MSCC reactor breaks up heavy hydrocarbon molecules into smaller molecules to produce marketable
products. This cracking process takes place on the surface of a circulating, powdered catalyst within the
fluidized bed-type MSCC reactor. The flue gas from the catalyst regeneration process consists primarily
of nitrogen, carbon dioxide, water, and oxygen with a lower concentration of pollutants. A continuous
opacity monitoring system (COMS) is used to demonstrate compliance with MSCC metal HAP emission
limits. A CO CEMS is used to evaluate compliance with the organic HAP emissions limit. The MSCC
operated for 4,394.8 hours in the reporting period.
The MSCC at BWO is subject to the NSPS for particulate matter (PM) as specified in NSPS Subpart J.
Per $63.156a(a)(l) and Item I of Table I to Subpart LI[[J, BWO must comply with the metal HAP
emission limits of Subpart UUU by complying with NSPS Subpart J and is subject to limits of 1.0 lb
PM/1,000 lb of coke bum-off and 30% opacity, except for one six-minute average opacity reading in any
one-hour period. Per $63.156a@)Q) and Item I of Table 2 to Subpart (ft U, a 3-hour rolling average
opacity no greater than 20%o must also be maintained. During periods of startup, shutdown, or hot
standby, BWO may, altematively, elect to demonstrate compliance by utilizing the alternative standard
(i.e., maintain inlet velocity to primary internal cyclones of the MSCC regenerator at or above 20
ft/second) in accordance with $63.1 56a(a)(5Xii).
For organic HAP compliance, the MSCC at BWO is subject to the NSPS for carbon monoxide (CO) as
specified in 40 CFR 60 Subpart J. Per $63.1565(aXl) and Item I of Table 8 to Subpart LruU, BWO must
comply with the organic HAP emission limits within Subpart UUU by complying with 40 CFR 60
Subpart J; CO emissions from the MSCC must not exceed 500 parts per million by volume on a dry basis
(ppmvd). During periods of startup, shutdown, or hot standby, BWO may, alternatively, elect to
demonstrate compliance by utilizing the altemative standard (i.e., maintain oxygen concentration
exhaust gas from the regenerator at or above I vol%) in accordance with $63.1565(a)(5xii).
MSCC Opacity Limits and Alternative Standard
There were no deviations from the 6-minute opacity emission limit (i.e., opacity of emissions must not
exceed 300%, except for one 6-minute average opacity reading in any l -hour period) during the reporting
period.
There were also no deviations from the 3-hr rolling average opacity operating parameter limit (i.e., above
20oh on a 3-hour rolling average).
MSCC Coke Burn-Off
There were no deviations from the coke bum-off emission limit (l.0 lb PM/I000 lb coke bumed
off). Details on performance testing for compliance evaluation against this limit are described in the final
section of this report.
MSCC CO Emissions and Alternative Standard
There were eight deviations from the CO emission limit (i.e., above the hourly average standard of 500
ppm). In each case, the MSCC complied with the altemate organic HAP emission limit of startup,
shutdown, and hot standby (i.e., maintain Oz concentration in exhaust from the catalyst regenerator >l o%
vol, dry basis).
Date
Start
Time
End
Time
CO Conc,
(nnmvd)Descrintion
Oz Conc.
(ohl
Complied witt
Alt. std.?
9t23t2024 I l:00 l2:00 806
MSCC shutdown and startup due to a
plant-wide power failure caused by the
Rocky Mountain Power substation fire.
10.0 Yes
9t23t2024 l2:00 l3:00 88s 10.0 Yes
9123t2024 l3:00 l4:00 701 10.0 Yes
9t2312024 l6:00 l7:00 752 9.9 Yes
9t23t2024 17:00 l8:00 608 6.8 Yes
912412024 0l:00 02:00 549 10.0 Yes
9t24t2024 02:00 03:00 559 9.8 Yes
912412024 04:00 05:00 643 10.0 Yes
Since the unit complied with either the emission limit or altemate standard at all times, there were no
deviations from work practice standards for CO during this reporting period. Therefore, further details
regarding deviations as described in the reporting requirements of $63.1575(e) are not applicable.
CBMS & COMS Deviations and Downtime
Information related to monitor status for MSCC Opacity, MSCC CO, MSCC Oz, and SRU Oz
concentration are included within the State Electronic Data Reports (SEDR) that cover this reporting
period that were submitted to the Utah Division of Air Quality (UDAQ). In accordance with
$63.1575(c)(4), $63.1575(e), and $63.1575(g), all information related to CEMS/COMS unavailability and
excess emissions not included within this report are included within those reports.
Note: The MSCC Regenerator Vent CO limit for MACT Subpart UUU is reported in the SEDR (500
ppmvd CO, uncorrected); therefore, any deviations from the MACT UUU limit are included in the SEDR
report. Also, the MSCC Flue Gas Opacity limit for MACT Subpart UUU (30% opacity over 6 minutes
and20o/o over 3-hour rolling average) differs from that which is reported in the SEDR (20%o opacity over
6 minutes); therefore, any deviations from the MACT UUU opacity limit are included in this report
above.
Performance Tests, Performance Evaluations, and Emission Standard Applicability
For purposes of $63.1575(0(1), BWO conducted one RATA on the SRU for Oz. In accordance with
$63.1575(k)(2), the pertinent information was submitted through the EPA's Electronic Reporting Tool
(ERT). Details on the performance evaluation are included in the table below. The previous RATA on the
SRU Oz was performed on December 11,2023.
Date Conducted Location Parameters Evaluated
r0t22t2024 SRU SOz, Oz
BWO also conducted a performance test on the MSCC Flue Gas Stack for HCN during the reporting
period. BWO previously conducted the one-time performance test for HCN required by 40 CFR
63. I 5 7 I (a)(6) on June 28, 2016 . The recent performance test was conducted to confirm the prior HCN
emissions testing results. Concurrently, the test also determined a site-specific NH: emission factor for
more accurate emission inventory reporting. Details on the performance test are included in the table
below.
Date Conducted Location Parameters Evaluated
tu2212024 MSCC Flue Gas Stack HCN, NH:
BWO previously conducted a performance test on the MSCC Flue Gas Stack for PM emissions, including
coke burn-off rates, on December 15,2023.
BWO previously conducted a RATA on the MSCC Flue Gas Stack for COz, SOz, NOx, Oz, and CO on
April 11,2024.
In accordance with $63.1575(e)(13), there were no changes to the continuous emission monitoring
systems or continuous opacity monitoring systems, processes, or controls since the last reporting period.