What Chevron refineries do and where they are located

Chevron operates nine refineries in the United States, each converting crude oil into gasoline, diesel, jet fuel, and other petroleum products. The refineries are located in Richmond, California; El Segundo, California; Salt Lake City, Utah; Pascagoula, Mississippi; Corpus Christi, Texas; Midland, Texas; Lummus Park, Arkansas; Honolulu, Hawaii; and Kapaau, Hawaii. Each facility processes crude oil through a series of chemical and thermal processes to separate and refine it into usable fuels and feedstocks for other industries.

The refining process begins with crude oil arriving by pipeline, tanker, or rail. The oil enters a furnace where it is heated to around 700 degrees Fahrenheit, then sent to a fractionation column where different components separate based on their boiling points. Lighter molecules like gasoline rise to the top; heavier molecules like fuel oil sink to the bottom. From there, additional units like hydrotreaters, crackers, and reformers further process these streams into finished products that meet EPA and state fuel specifications.

Chevron's refineries also produce chemical feedstocks — raw materials that petrochemical plants use to make plastics, fertilizers, solvents, and other chemicals. This dual output means a single refinery complex often serves both the fuel market and the chemical manufacturing industry.

Key Takeaways

  • Chevron operates nine U.S. refineries that convert crude oil into gasoline, diesel, jet fuel, and chemical feedstocks through heating, separation, and chemical treatment.
  • The refining process uses furnaces, fractionation columns, hydrotreaters, and crackers to break down and recombine crude oil molecules into products that meet federal and state fuel standards.
  • Refineries are regulated by the EPA under the Clean Air Act and Clean Water Act, and by state environmental agencies that set additional limits on emissions and wastewater discharge.
  • Chevron refineries employ thousands of workers in operations, maintenance, engineering, and safety roles, with most facilities located in California, Texas, Mississippi, Utah, Arkansas, and Hawaii.

The main refining units and what they produce

The crude distillation unit (CDU) is the heart of every refinery. Crude oil enters the furnace, gets heated, and flows into the fractionation column where temperature differences separate it into streams. The top of the column is coolest and collects the lightest molecules — naphtha and gasoline range material. The middle collects kerosene and diesel range material. The bottom collects heavy gas oil and residue. Each stream then moves to specialized units for further processing.

The fluid catalytic cracker (FCC) takes heavier molecules from the CDU and breaks them into lighter, more valuable products like gasoline and propylene. Heat and a powdered catalyst cause large hydrocarbon chains to split. This unit is critical because it allows refineries to convert low-value heavy oil into high-value gasoline and chemical feedstocks.

The hydrotreater removes sulfur, nitrogen, and other impurities from various streams. Hydrogen gas and a metal catalyst cause these contaminants to bond and separate out. Federal law requires gasoline to contain no more than 10 parts per million of sulfur, and diesel no more than 15 parts per million. Hydrotreaters may support finished fuels meet these limits.

The reformer rearranges the molecular structure of naphtha-range material to increase octane rating, making gasoline suitable for high-performance engines. The alkylation unit combines smaller hydrocarbon molecules to create high-octane gasoline blending components. Together, these units allow refineries to tailor fuel properties to market demand and seasonal requirements.

Environmental regulations and monitoring at refineries

Chevron refineries operate under the Clean Air Act, which requires facilities to obtain a Title V operating permit from their state environmental agency. This permit sets limits on emissions of volatile organic compounds (VOCs), nitrogen oxides (NOx), sulfur dioxide (SO2), particulate matter, and other pollutants. Refineries must install continuous emissions monitoring systems (CEMS) on major stacks and report data to the EPA quarterly.

The Clean Water Act requires refineries to treat wastewater before discharge into rivers, bays, or municipal systems. Wastewater from crude distillation, cooling towers, and process units contains oil, suspended solids, and dissolved chemicals. Treatment typically involves oil-water separation, biological treatment, and settling before the water leaves the facility. State water quality standards vary; California refineries face stricter limits than facilities in other states.

Refineries must also comply with the Risk Management Program (RMP) rule, which requires facilities handling hazardous chemicals above threshold quantities to develop plans to prevent accidental releases and respond if one occurs. Chevron refineries maintain buffer zones, install safety systems, and conduct regular inspections to meet these requirements. Local fire departments and emergency responders receive copies of RMP plans so they can prepare for potential incidents.

Spill prevention and response plans are required under the Oil Pollution Act. Refineries must have secondary containment for storage tanks, regular inspections of pipelines and equipment, and trained response teams. If a spill occurs, the facility must report it to the EPA and state agencies within specific timeframes and take steps to contain and clean it up.

Employment and workforce at Chevron refineries

Chevron refineries employ operators, technicians, engineers, maintenance workers, safety specialists, and administrative staff. Operators monitor control room systems and adjust process parameters to maintain product quality and safety. Technicians perform preventive maintenance on equipment, replace worn parts, and troubleshoot problems. Engineers design improvements, oversee construction projects, and may support compliance with regulations.

Most refinery jobs require a high school diploma or equivalent. Many operators and technicians complete apprenticeships or earn certifications in process technology or industrial maintenance. Some positions require a bachelor's degree in chemical engineering, mechanical engineering, or environmental science. Chevron offers training programs and tuition information for employees pursuing relevant credentials.

Refinery work involves shift schedules, including nights and weekends, because refineries operate 24 hours a day, 365 days a year. Safety is a core requirement; workers must follow strict protocols, wear personal protective equipment, and report hazards when ready. Chevron facilities have safety committees and conduct regular training on emergency procedures, confined space entry, and hazard communication.

Crude oil sourcing and feedstock variability

Chevron refineries process crude oil from multiple sources: some from Chevron's own production operations, some purchased from other oil companies, and some imported. The type of crude oil affects refinery operations. Light crude oil is easier to refine and yields more gasoline; heavy crude oil requires more processing and yields more fuel oil and residue. Refineries adjust their operations based on the crude slate they receive.

Crude oil prices fluctuate based on global supply and demand, geopolitical events, and production changes. When crude prices rise, refinery margins — the difference between the cost of crude and the selling price of products — typically narrow. Refineries respond by optimizing operations, running at different rates, or shifting the product mix toward higher-margin fuels.

Seasonal demand also affects refinery operations. Summer driving season increases gasoline demand, so refineries maximize gasoline production. Winter brings higher heating oil demand in colder regions and increased jet fuel demand for holiday travel. Refineries adjust their processing schedules and product blending to match these seasonal patterns.

Safety systems and incident prevention

Modern refineries use multiple layers of safety systems to prevent accidents. Process control systems monitor temperature, pressure, and flow rates continuously and automatically shut down units if parameters exceed safe limits. Pressure relief valves release excess pressure before equipment can rupture. Flame arrestors prevent explosions in pipes and vessels. Interlocks prevent operators from taking unsafe actions — for example, a valve cannot open if doing so would create a dangerous condition.

Refineries conduct regular inspections of equipment, pipelines, and storage tanks to detect corrosion, leaks, or wear before failure occurs. Ultrasonic thickness testing measures pipe wall thickness to predict remaining service life. Thermography detects hot spots that indicate equipment problems. Vibration analysis identifies bearing wear and misalignment in rotating equipment.

Incident investigation is standard practice. When an accident, near-miss, or equipment failure occurs, a team investigates the root cause and implements corrective actions to prevent recurrence. Findings are shared across the company so other facilities can learn from the incident. This approach has reduced refinery accident rates significantly over the past two decades.

Product distribution and market reach

Finished products leave Chevron refineries by pipeline, truck, rail, or ship. Gasoline and diesel typically move through product pipelines to distribution terminals, where they are stored and then loaded into tanker trucks for delivery to gas stations. Jet fuel moves through dedicated pipelines to airports or is shipped by truck. Fuel oil and other heavy products are often shipped by barge or tanker to power plants, marine terminals, or industrial customers.

Chevron's nine refineries have a combined capacity of approximately 1.8 million barrels per day, though actual throughput varies based on maintenance schedules, crude availability, and market demand. The Richmond refinery is the largest, processing around 240,000 barrels per day. Smaller refineries like those in Hawaii process 45,000 to 55,000 barrels per day to serve local markets.

Product quality is verified through laboratory testing before shipment. Gasoline is tested for octane rating, vapor pressure, sulfur content, and other properties. Diesel is tested for cetane number, cloud point, and sulfur content. These tests may support products meet ASTM International standards and EPA fuel specifications, which vary by season and region.

Frequently Asked Questions

How long does it take crude oil to become gasoline at a refinery?

Crude oil moves through the refinery continuously, not in batches. From the moment crude enters the furnace to the moment finished gasoline leaves the facility typically takes 24 to 48 hours, depending on the refinery's configuration and the type of crude being processed. Some light crude can move through faster; heavy crude requires more processing time.

What happens to the heavy residue left after refining?

Heavy residue from the bottom of the fractionation column becomes fuel oil, which power plants and ships burn for energy. Some residue is sent to a coker, which heats it to very high temperatures and converts it into coke (a solid carbon product used in steel and aluminum production) and lighter liquid products. This maximizes the value extracted from each barrel of crude.

Can refineries switch between different types of crude oil quickly?

Switching crude types takes time because the refinery must drain the old crude from pipelines and storage, flush the system, and adjust process parameters for the new crude's properties. A complete switch typically takes several days. Refineries often blend different crude types to maintain consistent feedstock properties and avoid frequent adjustments.

Do refineries produce plastic or just fuel?

Refineries produce both. They produce gasoline, diesel, and other fuels for transportation and heating. They also produce chemical feedstocks like ethylene, propylene, and benzene, which petrochemical plants use to manufacture plastics, fertilizers, solvents, and other chemicals. A single refinery complex often has both fuel and chemical production.

What is the difference between a refinery and a chemical plant?

A refinery separates and processes crude oil into fuels and basic chemical building blocks. A chemical plant takes those building blocks and combines them into finished chemicals like plastics, pesticides, and pharmaceuticals. Some facilities do both, but they are distinct operations with different equipment and processes.