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Chevron Richmond Re�inery Wet Gas Scrubber Project
Project Description
March 2024
1.0 INTRODUCTION
1.1 Project Overview
Chevron Products Company (Chevron), a division of Chevron U.S.A. Inc., operates a petroleum refinery (the Facility) in Richmond, CA 94802. The Facility processes crude oil blends, externally sourced gas oils, and natural gas into various fuel and oil products. The Facility produces motor gasoline, jet fuel, diesel fuel, lubricating oils, industrial fuel oil, liquefied petroleum gas, sulfur, and other products. The Facility also produces steam, electricity, fuel gas, and hydrogen, primarily for its own use.
In July 2021, the Bay Area Air Quality Management District (BAAQMD) adopted amendments to BAAQMD Regulation 6, Rule 5 (Rule 6-5): Particulate Emissions from Refinery Fluidized Catalytic Cracking Units (FCCU) to reduce particulate matter (PM) emissions, including condensable PM, sulfur dioxide (SO2), and ammonia, from petroleum fluid ized catalytic cracking units ( FCCUs). The new emissions limits , excerpted below, are effective July 21, 2026.
Figure 1-1: BAAQMD Rule 6-5 Emission Limits (Table 1 of the Rule)
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To comply with Rule 6-5 requirements, BAAQMD identified operational controls or equipment that may be required.1 For controlling PM emissions from FCCUs , BAAQMD identified wet gas scrubbers as the likely air pollution control measure.
The Facility will be applying for the installation of a Wet Gas Scrubbing System (WGS) at its FCCU because, consistent with the BAAQMD’s AB617 Expedited BARCT Implementation Schedule EIR, a WGS provides the best opportunity for consistent and sustained compliance with the Rule 6-5 Total PM10 limit of 0.010 grains per dry standard cubic foot (gr/dscf) at 5% excess oxygen (O 2) on a rolling four-quarter basis.
1.2 Project Objectives
The WGS Project is designed to meet the following objectives:
• Performance- Comply with Rule 6-5 emissions limits;
• Performance –Reduce PM at the FCCU while maintaining it’s current throughput processing capacity, and
• Schedule – Meet the compliance date of July 21, 2026, or as soon as possible thereafter.
2.0 PROJECT DESCRIPTION
2.1 Project Location
Chevron owns and operates the Facility, located along the western edge of the City of Richmond (City), in Contra Costa County (County), California . The Facility is about 2,153 acres along the western boundary of Richmond, as shown in Figure 2-1. The main portion of the Project site is bounded by Castro Street to the southeast and Interstate 580 to the south.
The residential communities of Atchison Village, Santa Fe, and Iron Triangle are located southeast of the Facility, across Castro Street and Garrard Boulevard; Shields -Reid community and Parchester Village are located northeast of the Project site; and Point Richmond is located to the southwest . Point San Pablo Yacht Harbor, where some residents may reside in house boats, is located north of the Project site. Point San Pablo Peninsula and San Francisco Bay form the western border of the Facility and San Pablo Bay forms the northern boundary of the Facility.
Figure 2-2 shows the WGS Project area. The WGS would be installed at the south-east perimeter of the FCCU, at the vacant area east of the cracking control room , previously occupied by the decommissioned “old” Alkylation Plant. All the Project construction staging areas will be located within the Facility boundary.
1 See BAAQMD, AB617 Expedited BARCT Implementa�on Schedule EIR, p. 2-11 to 2-12, available at htps://www.baaqmd.gov/~/media/files/ab617-community-health/barct/20181022_noadeir_ab617_barct- pdf.pdf?rev=2d81be53517e455aba23e7363385d781&sc_lang=en.
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Figure 2-1: WGS Project Location
Figure 2-2: WGS Project Area
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2.2 Existing FCCU Process Description
The FCCU converts high -boiling point hydrocarbon fractions of crude oil into gasoline and other petroleum products. The conversion process is achieved through a chemical process that occurs in a reactor vessel that incorporates the use of heat and a catalyst to break up, or “crack,” long-chain hydrocarbons into smaller-chain hydrocarbons.2 The catalyst is in the form of very fine particles that acts as a fluid when aerated. Hydrocarbon feed is preheated and introduced into the bottom of the reactor’s riser with hot regenerated catalyst. The hot catalyst vaporizes the feed, bringing both to the desired reaction temperature, 470 to 525°C (880 to 980°F).
Nearly 100% of the desired cracking reaction takes place in the travel up the riser. Large paraffinic hydrocarbon molecules break up, or "crack," into smaller molecules that flow overhead to a fractionator for separation into products. The spent catalyst falls to the bottom of the reactor and is steam stripped as it exits the reactor bottom to remove absorbed hydrocarbons. The spent catalyst is then routed to the regenerator where the carbon deposited on the catalyst from the cracking reactions is combusted off with preheated air. The hot regenerated catalyst then returns to the reactor for another cracking cycle. The flue gas is routed through a waste heat steam generator (WHSG) where the flue gas is cooled prior to entering the electrostatic precipitator (ESP) for particulate removal, then through an economizer before exiting out the stack. The economizer recovers heat from flue gas and preheats the feed water for steam generating equipment (e.g. WHSG ) at the FCCU . A simplified process flow diagram of the existing FCCU process is shown in Figure 2-3.
Figure 2-3: Existing FCCU Simplified Process Block Flow Diagram
2 Addi�onal informa�on is available at htps://www.epa.gov/sites/default/files/2020- 09/documents/5.1_petroleum_refining.pdf Section 5.1.2.2.1
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2.3 Project Characteristics
2.3.1 WGS Project Equipment List
The WGS will include the following equipment.
Table 2-1: WGS Equipment List
The Project will also include the following to support the equipment listed in the above table:
• Piping/hardware
• Electrical and instrumentation
• Civil/Structural/Control Systems
Key interfaces between the Project and the Facility are as follows:
• All new equipment will be installed downstream of the existing ESP. • Ducting will re-direct flue gas from the existing stack/economizer to the new WGS/economizer. • Refinery usage of potable water will increase approximately 6% (~387,000 average gallons per day) and less than the maximum of ~441,000 gallons per day (GPD) • Additional water discharge to the Facility wastewater treatment system of ~ 87,000 GPD; • The Facility’s existing caustic storage system located at the FCCU will be utilized to supply caustic to the WGS;
• Firewater can be used to operate the WGS in the event of an unforeseen loss of water supply or unplanned process event where there is more than typical particulate in the flue gas,
Equipment Name Quantity New/
Replacement Description/Purpose
Wet Gas Scrubber (WGS) 1 New 22’-6” ID x 123’, scrubber; 12” ID x 75’stack Economizer (includes blower & fans) 1 Replacement Cools flue gas prior to entering the WGS WGS Spray Tower Recirculation Pumps 3 New Pumps recirculated scrubbing water around spray tower WGS Filtering Module Pumps 2 New Pumps NaOH solution to the WGS filtering modules WGS Make-Up Water Pumps 2 New Pumps potable make-up water to WGS spray tower WGS Coagulant Metering Pumps 2 New Pumps coagulant to Clarifer mixing tank WGS Coagulant Tote 1 New Storage tote for coagulant
Mixing Tank 1 New Mixes solids and coagulant upstream of clarifier Clarifier 1 New Settles solids from WGS purge stream
Oxidation Tank & Mixers 2 New Size 6’-5.5’ ID x 20’-6’ tall Oxidation Air Blowers 3 New Provides air to oxidation tanks Filtering Bins 3 New Collects clarifier underflow for off-site disposal Filtrate Sump Pumps 2 New Pumps filtrate liquid from filter bins back to clarifier PTU Effluent Surge Tank 1 New Reservoir for PTU effluent PTU Effluent Pumps 2 New Pumps PTU effluent to PTU effluent cooler PTU Effluent Cooler 1 New Cools PTU effluent prior to discharge to Refinery WWTP WGS Caustic Supply Pumps 2 New Pumps NaOH solution to oxidation tanks Power Distribution Center 1 New Enclosure for new electrical equipment Continuous Emission Monitors (CEMS) Enclosure 1 Replacement Enclosure for NOx, CO, O2, SOx CEMS
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2.3.2 WGS Process Description
The WGS uses water to entrain particulate matter. It will be installed downstream of the existing ESP to reduce air particulate matter emissions. Scrubber effluent containing entrained particulate matter is then pumped from the bottom of the WGS to a purge treatment unit (PTU), which separates the particulates from the purge water and pretreats the scrubber effluent before being routed to the Facility’s existing Wastewater Treatment Plant (WWTP). The separated particulate matter will be disposed of offsite as waste.
Figure 2-4 illustrates the project elements along with the key interfaces between the Project and the Facility. Figure 2-5 provides a three -dimensional view of the Project elements integrated into the FCCU. Detailed descriptions of each process step are provided in the subsections below.
Figure 2-4: WGS Project Schematic
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Figure 2-5: Three-dimensional Project Integration Schematic
Economizer
As shown in Figure 2-4 the existing FCCU economizer, along with the stack it is attached to, will be decommissioned as part of the Project. The existing economizer recovers heat from the FCCU flu gas by preheating feed water used at steam generating equipment at the FCCU.
As shown in Figure 2-4 and 2-5 the proposed Project will install a replacement economizer downstream of the ESP and upstream from the wet gas scrubber vessel. The replacement economizer will serve two purposes: ( 1) recover waste heat from the FCCU flue gas by p reheating feedwater used at steam generating equipment at the FCCU and, (2) reduce the flue gas temperature prior to entering the WGS vessel which reduces the evaporation rate of water from the WGS, thus conserving water. The replacement economizer, sized at the same capacity of the existing economizer , will not increase production nor will it result in a net increase in steam production at the FCCU.
Scrubber Operation
After exiting the economizer, the hot flue gas containing SOx gases and FCCU catalyst fines (i.e particulates) flows via ducting to the WGS. The SOx gases and particulates are removed in the Quench Section and Scrubbing Section of the Spray Tower (i.e. lower section of the WGS) and the remainder is removed in the Filtering Modules and by spray nozzles (i.e. upper section of the WGS). The intensive gas/liquid contacting provides for the effective removal of particulate and desulfurization. To further conserve water, the scrubber will be designed with Belco vane droplet separators and a stack droplet
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separator to remove water droplets from the flue gas before its release to atmosphere through the stack.
A schematic depicting a typical BELCO® 6000 Wet Scrubbing System is shown in Figure 2-6.
Flue gas from the FCCU enters the Spray Tower horizontally at the Quench Section and is cooled to its saturation temperature . The flue gas is quenched by spraying circulated water solution (i.e. scrubbing water solution) from three spray nozzles. The sprayed water flows down the walls to the bottom of the vessel and drains to an internal recirculation tank. The internal recirculation tank is built into the bottom of the tower. The recirculation loop supplies scrubbing water solution to the inlet spray nozzles and to the scrubber’s spray nozzles. This loop is continuously monitored at the Digital Control System (DCS) for pH, pressure, pump motor current, and pump run status. The pH is controlled at
7.0. The SOx absorption takes place in the vertical up-flow portion of the Spray Tower (immediately above the Quench Section (i.e. Absorber Section) which has three spray levels. Multiple levels of sprays are used to provide staged removal of S Ox. Caustic (NaOH) solution consisting of approximately 15 percent sodium hydroxide and 85 percent water is fed into the scrubbing liquid to react with the dissolved SOx forming sodium sulfate solids that are removed in the Filtering Modules (FM ). The NaOH solution maintain s neutral (7.0) pH of the scrubbing liquid to avoid the scrubbed SOx from forming sodium bisulfate as a byproduct of the scrubbing reaction. Sodium bisulfate solution is acidic and causes corrosion. The Spray Tower is equipped with three pumps for circulating the scrubbing solution. Two of the three pumps operate continuously. The third pump is a standby spare with auto- start.
Directly above the Spray Tower section are the up-flow FM s. In the modules, the flue gas is accelerated (compressed) then decelerated (expanded) through a convergent/divergent venturi section. This causes the water to condense on the module walls, washing the surface. At the top of the FMs, removal of the enlarged agglomerated fine particulate and mists (including condensed SOx) occurs by filtration through high-density spray nozzles.
The FM recirculation loop is equipped with venturi nozzles and spray nozzles. This loop is equipped with two capacity pumps; one pump is operated continuously, and the other is a standby spare with auto-start. The FM recirculation is continuously monitored for pH, pressure, pump motor current, and pump run status. The pH is controlled at 7.0. Make-up water is introduced into the WGS at the internal FM catch pan.
After passing the FM, the gas enters the three-stage droplet separator. The residual water droplets are separated from the flue gas with BELCO vane droplet separators. Agglomerated liquids drain from each stage as large droplets or as a liquid stream. The flue gas, mostly free of water droplets, flows to the stack.
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Figure 2-6: BELCO Wet Gas Scrubber
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Purge Treatment Unit (PTU)
Scrubber water is purged from the Spray Tower recirculation loop to control the content of dissolved salts, calcium, chlorides, and suspended catalyst solids in the WGS. Scrubber purge water is discharged to the PTU . The PTU includes the Clarifier, Filtrate Pump, Coagulant Metering Pump, Oxidation Tanks, Oxidation Tank Blowers, and associated equipment, piping, valves, etc.
Catalyst solids, aided by coagulant, settle, and collect as a thickened slurry in the Clarifier. A rake drive mechanism promotes proper bed formation and prevents the solids bed from compacting. The solids settle out of the purge water and the clarified liquid overflows by gravity to the oxidation tank.
The solids – the underflow from the Clarifier is directed by gravity to one of three Filter Bins on a batch basis. Excess liquid from the Clarifier underflow is removed from the solids by gravity filtration, collected and circulated back into the Clarifier.
Clarifier overflow is processed through two Oxidation Tanks in series to reduce the effluent chemical oxygen demand (COD). Oxidation is achieved by contacting the clarified liquid with low-pressure air supplied by two (2) of the three (3) Oxidation Tank Blowers. One blower is an installed spare. Within each Oxidation Tank, a turbulent gas/liquid mixing zone is created by Oxidation Tank Mixers. Based on the pH within each tank, NaOH solution is added to each oxidation tank to maintain optimum oxidation conditions. The overflow from Oxidation Tank is discharged to the Facility wastewater treatment system after being cooled to ambient conditions via a heat exchanger.
Power Distribution Center and Electrical Equipment
The Project will require 822kW power and will utilize electricity from the Facility grid for supply. The proposed Project includes the installation of a new Power Distribution Center (PDC) to house, meter and control the electrical equipment used to power the Project’s new electric powered equipment. The PDC will include variable frequency drives, UPS systems, communication panels, and control switchboards. The PDC will not be utilized for any other equipment at the FCCU.
The new PDC will be powered by a new above ground 12 kilovolt (KV) feeder routed from the existing FCCU substation. The Project will install new transformers to reduce the 12KV feed voltage to 4160V and 480V. Two new 2000 KVA transformers and two 1500 KVA transformers will be installed to get to service voltage.
The Project will install new electric motors for the operation of pumps for potable-water make-up supply, scrubber solution circulation, wastewater transfer, and chemical supply. Electric motors will drive the mixers on the PTU tanks and drive the aeration blowers on the oxidation tanks.
2.4 Project Construction
The construction phases are described below, and the heavy-duty truck trips and off-road equipment required for demolition, site preparation, and WGS construction are provided in Tables 2-2 and 2-3. The demolition, site preparation, and WGS construction will be performed in sequence. Total duration of demolition, site preparation, and WGS construction expected to last 18 months.
2.4.1 Demolition
Demolition of existing equipment is minimal and is expected to take approximately 85 days . The existing ductwork from the existing ESPs to the existing FCCU stack will be demolished so that it can
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be replaced by ductwork and tie -in to the WGS . A portion of the existing pipe rack associated with the demolished “ old” Alkylization Unit will be demolished to clear WGS plot space. Equipment required for demolition will include pick-up trucks, tractor trucks , a bus for onsite craft personnel transport, air compressors, welding machines, and excavator(s).
2.4.2 Site Preparation
Site preparation is expected to take approximately 135 days . Site grading will ensure proper soil conditions to allow installation of concrete foundations, associated piping, electrical infrastructure, control equipment and other appurtenances associated with install ing and operating the WGS and managing the WGS waste/effluent. Equipment required will include pick-up trucks, tractor trucks, a bus for onsite craft personnel transport, a concrete pump, air compressors, welding machines, excavators, and a pile driver.
2.4.3. WGS Construction
WGS construction is expected to last approximately 330 working days to complete . During construction, deliveries of materials such as concrete, structural steel, pipe and fittings, mechanical and electrical equipment, insulation, and construction services equipment (e.g., portable toilets) would be delivered by truck and offloaded at equipment laydown, staging, and assembly areas. Equipment required will include, but is not limited to, pick-up trucks, tractor trucks, a bus for onsite craft personnel transport, concrete pump, air compressors, welding machines, forklifts, manlifts, and heavy cranes. The cranes and forklifts would be used to transfer equipment from delivery trucks to lay down, staging, and assembly areas.
Table 2-2: Construction On-Road Truck Trips
Number of Heavy-Duty Truck Trips
Demolition Site Preparation WGS Construction Total Construction 520 376 292 1,188
Table 2-3: Construction Off-Road Equipment Hours
Equipment
Project Construction Total Daily Hours
Demolition Site
Preparation
WGS
Construction
Aerial Lifts – – 24
Air Compressors 9 18 27
Cranes 4 8 12
Excavators 8 16 –
Forklifts 6 12 12
Welders 8 16 24
Crawler Crane – 8 –
Hi-Lift Loader – 8 –
Impact Hammer – 8 –
1. Total hours equal quantity of equipment x estimated total hours daily hours used.
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2.4.4 Construction Staffing and Employment
The entire contractor construction workforce is expected to come from the construction labor pool available in the Bay Area. Over the WGS Project’s construction period, it is estimated that a total of 336,101 work hours will be required. The estimated construction workforce hours are summarized in Table 2-4.
Table 2-4: Estimated Total Project Worker Hours
Category Estimated Total Project Worker Hours
Demolition Site Preparation WGS Construction
Worker Hours 16,283 107,517 209,901
2.4.5 Construction Traffic and Parking
Multiple construction staging areas for the WGS Project would be located within the Facility boundary.
The majority of the WGS equipment will be installed in the vacant field and parking area east of the Cracking Control Room. Project construction workers will park at the Gate 91 lot in the Facility boundary and ride a bus to the Project construction site. Chevron does not allow personal vehicles inside the Facility.
2.4.6 Construction Wastes
The WGS Project area overlaps an area previously occupied by the “old ” Alkylation Plant which has since been demolished. All soils from excavation necessary to install foundations and sumps would be treated as contaminated soil, unless tested and confirmed to be non- hazardous. The estimated quantities of excavated soil, concrete, steel, asbestos and lead paint, and other demolition debris requiring disposal are summarized in Table 2-5.
Table 2-5: Estimated Construction Wastes
Waste Material Quantity
Excavated Soil 6,158 cubic yards
Removed Concrete 1,374 cubic yards
Steel 27 tons
Asbestos/Lead Paint 1 ton
Other Demolition Debris ⁓300 tons
The presence of lead paint and/or asbestos would be determined through laboratory testing prior to demolition of any Project component. If disturbance of asbestos or lead paint is required, the contaminated materials would be managed in accordance with applicable regulations.
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2.5 Project Operations
The WGS is an air pollution control measure for controlling PM emissions from FCCUs. BAAQMD identified wet gas scrubbers as the likely air pollution control measure in its AB617 Expedited BARCT Implementation Schedule EIR. The Project will not increase or change the output of products from the Facility. The BAAQMD estimates that the implementation of Rule 6-5 will reduce Total PM10 at the Chevron’s Richmond FCCU by 65% from current emissions3.
2.5.1 Water Requirements
The WGS requires very high-quality water to work properly in accordance with Belco specifications.
Accordingly, the Project has been carefully designed to minimize potable water usage. Those water- reducing features include installing the replacement economizer, the Belco vane/droplet separator, and the stack droplet separator, which are discussed above. Most of the Project’s water usage is the make- up water to the WGS, which compensates for water losses through purge to the PTU and evaporation in the scrubber. The Project’s water use is expected to range from approximately 328,000 GPD to 441,000 GPD, with an average of 387,000 GPD. For context, this average water use is approximately 6% of the Facility’s typical potable water usage.
During FCCU unplanned events or equipment malfunctions that could produce more than typical particulate in the flue gas , additional quench water would be supplied from the Facility ’s fire water system if needed. The purge rate to the Clarifier would be increased to help reduce the concentration of suspended solids in the WGS following the upset event.
2.5.2 Energy
The WGS Project will have an electrical demand of 822 kiloWatts to operate the new electrical equipment (e.g. pumps). The Project electrical load requirements are summarized in Table 2-6. Where A/B loads are shown for a specific service, only one motor runs at a time. Where A/B/C loads are shown, two of three motors run at any one time.
3 Final Staff Report-Proposed Amendments to Regulation 6,Rule 5: Particulate Emissions from Petroleum Refinery Fluidized Catalytic Cracking Units. 20210525_13_fsr_0605-pdf.pdf (baaqmd.gov)
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Table 2-6: Summary of Energy Requirements
2.5.3 Other Utilities
The WGS Project will require additional utilities, including instrument air and cooling water to operate effectively and efficiently. The Project will install three utility stations providing steam, plant air and water for occasional use. The utility steam, plant air and water will tie into the existing utility systems at the FCCU. The instrument air will provide compressed air for operation of plant instrumentation.
Recirculated cooling water from the existing FCCU cooling water tower will be circulated through the PTU cooler, which is used to cool the scrubber effluent. Max imum usage rates are summarized in Table 2-7.
Table 2-7 : Summary of Utility Requirements
Utility Requirement Purpose
Instrument Air 1,681 standard cubic feet permit scfh Provide air for instrumentation Cooling Water 1,972,947 MMBtyu/hr; 174 GPM Recirculate cooling water used at PTU cooler
1.The cooling water circulated at the PTU is not expected to affect the existing FCCU cooling water tower operation or water consumption because the circulation rate at the PTU is about 0.3% of typical FCCU cooling tower recirculation rate.
Device Description
Number
of Units
Installed
Number of
Units
Operation
Rated
Power
Operating
Load
Electric
Load per
Motor
Total
Electrical
Load
(hp) (hp) (kW) (kW)
Soot Blowers 8 8 1.5 0.2 0.15 0.15
Seal Air Fans 1 1 15 10 7.46 7.46
Clarifier Mix Tank Agitator 1 1 5 5 3.73 3.73
Clarifier Rake 1 1 5 5 3.73 3.73
Oxidation Tank Mixers 2 1 20 20 14.92 14.92
Oxidation Blowers 3 2 75 34 25.36 50.73
Make-up Water Pump 2 1 30 22 16.41 16.41
Spray Tower Pump 3 2 200 152 113.39 226.78
Filtering Module Pump 2 1 700 658 490.87 490.87
Coagulant Metering Pump 1 1 0.5 0.5 0.37 0.37
Filtrate Sump Pump 1 1 5 1.9 1.42 1.42
Caustic Supply Pump 2 1 5 1.8 1.34 1.34
PTU Effluent Pumps 2 1 10 6 4.48 4.48
Total 822 kW
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2.5.4 Wastewater Discharge Requirements
Wastewater generated at the WGS will be managed at the Facility wastewater treatment plant (WWTP). The Facility’s WWTP is regulated under National Pollution Discharge Elimination System (NPDES) permit Number CA0005134. The wastewater generated at the WGS will be routed to process sewers, and then flow to the No. 13 Oil Water Separator. Wastewater generation is expected to increase at a maximum flow rate of 87,000 GPD, which is about approximately 1% of the No. 13 Separator’s average flow rate of 7,412,000 GPD. Discharge from the No. 13 Separator flows to a bioreactor consisting of an aeration basin and settling basin. Discharge from the bioreactor flows through granular activated carbon. Treated Facility wastewater is discharged to San Pablo Bay via discharge point E-001. Location of E-001 is shown below in figure 2-7.
Figure 2-7: Wastewater Treatment Plant E-001
2.5.5 Hazardous Materials
The Project will pump 15% sodium hydroxide by weight and 85% by weight water solution into the scrubber on a continuous basis at a rate of approximately 4,320 GPD. NaOH solution will be supplied from an existing storage tank through new piping. The sodium hydroxide is used to maintain the pH of the scrubbing solution and neutralize the SO
x emissions, forming sodium sulfate as a byproduct.
Sodium hydroxide is designated as a hazardous material for corrosivity. With usage at approximately 4,320 GPD, the Project will require approximately one additional tank truck of 50% sodium hydroxide 50% water solution per day to be delivered to the Facility. The solution is diluted with water in the tank. This water usage was included in the WGS estimated water consumption previously mentioned.
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The Project will feed a polymer coagulant into the PTU to agglomerate the catalyst fines into larger, faster settling particles which will improve the solids removal efficiency of the clarifier. Typically, polymer coagulants are designated by California Code of Regulations (CCR) Title 22 as non-hazardous organic compounds. Polymer usage is estimated at 13 pounds per hour, or about one 55 -gallon drum of liquid coagulant every 2 days. Shipment of coagulant would require approximately one additional truck trip per month to the Facility . Partial truckloads may occur if the supplier combines Chevron’s order with orders from other customers . T hus two or more truck trips may occur per month for coagulant delivery.
2.5.6 Waste
Purge water would be discharged from the WGS at a maximum rate of approximately 60 gallons per minute (GPM). Approximately 38 pounds per hour (166 dry tons per year) of catalyst fines would be collected in the Filter Bins. There are two management options available for this waste:
Following dewatering, catalyst fines collected from the WGS would be tested to determine i f the FCCU catalyst exceeds the values given in CCR Title 22, Section 66268.106(a), Table I-C. If off- site Portland cement kiln s cannot accept wet waste, the catalyst fines would be managed as hazardous waste. The waste would be shipped to the Buttonwillow landfill, or an alternative hazardous waste landfill. This is the disposal option that is anticipated. Provided that the FCCU catalyst fines do not exceed the values given in Table I-C, Section 66268.106(a), with some exceptions, the catalyst may be recycled at Portland cement kilns as the substitute of alumina and silica in the kiln feed. This management approach is consistent with the way that catalyst fines from the existing ESP are managed. This option would only be available if the off-site cement kiln can accept wet waste.