overview of petroleum refining process

TABLE IV:2-3. OVERVIEW OF PETROLEUM REFINING PROCESSES.

Process name Action Method Purpose Feedstock(s) Product(s) FRACTIONATION PROCESSES Atmospheric distillation Separation Thermal Separate fractions Desalted crude oil Gas, gas oil, distillate, residual Vacuum distillation Separation Thermal Separate w/o cracking Atmospheric tower residual Gas oil, lube stock, residual CONVERSION PROCESSED--DECOMPOSITION Catalytic cracking Alteration Catalytic Upgrade gasoline Gas oil, coke distillate Gasoline, petrochemical feedstock Coking Polymerize Thermal Convert vacuum residuals Gas oil, coke distillate Gasoline, petrochemical feedstock Hydro-cracking Hydrogenate Catalytic Convert to lighter HC's Gas oil, cracked oil, residual Lighter, higher-quality products *Hydrogen steam reforming Decompose Thermal/ catalytic Produce hydrogen Desulfurized gas, O2, steam Hydrogen, CO, CO2 *Steam cracking Decompose Thermal Crack large molecules Atm tower hvy fuel/ distillate Cracked naphtha, coke, residual Visbreaking Decompose Thermal reduce viscosity Atmospheric tower residual Distillate, tar CONVERSION PROCESSES--UNIFICATION Alkylation Combining Catalytic Unite olefins & isoparaffins Tower isobutane/ cracker olefin Iso-octane (alkylate) Grease compounding Combining Thermal Combine soaps & oils Lube oil, fatty acid, alky metal Lubricating grease Polymerizing Polymerize Catalytic Unite 2 or more olefins Cracker olefins High-octane naphtha, petrochemical stocks CONVERSION PROCESSES--ALTERATION OR REARRANGEMENT Catalytic reforming Alteration/ dehydration Catalytic Upgrade low-octane naphtha Coker/ hydro-cracker naphtha High oct. Reformate/ aromatic Isomerization Rearrange Catalytic Convert straight chain to branch Butane, pentane, hexane Isobutane/ pentane/ hexane TREATMENT PROCESSES *Amine treating Treatment Absorption Remove acidic contaminants Sour gas, HCs w/CO2 & H2S Acid free gases & liquid HCs Desalting Dehydration Absorption Remove contaminants Crude oil Desalted crude oil Drying & sweetening Treatment Abspt/ therm Remove H2O & sulfur cmpds Liq Hcs, LPG, alky feedstk Sweet & dry hydrocarbons *Furfural extraction Solvent extr. Absorption Upgrade mid distillate & lubes Cycle oils & lube feed-stocks High quality diesel & lube oil Hydrodesulfurization Treatment Catalytic Remove sulfur, contaminants High-sulfur residual/ gas oil Desulfurized olefins Hydrotreating Hydrogenation Catalytic Remove impurities, saturate HC's Residuals, cracked HC's Cracker feed, distillate, lube *Phenol extraction Solvent extr. Abspt/ therm Improve visc. index, color Lube oil base stocks High quality lube oils Solvent deasphalting Treatment Absorption Remove asphalt Vac. tower residual, propane Heavy lube oil, asphalt Solvent dewaxing Treatment Cool/ filter Remove wax from lube stocks Vac. tower lube oils Dewaxed lube basestock Solvent extraction Solvent extr. Abspt/ precip. Separate unsat. oils Gas oil, reformate, distillate High-octane gasoline Sweetening Treatment Catalytic Remv H2S, convert mercaptan Untreated distillate/gasoline High-quality distillate/gasoline

* Note: These processes are not depicted in the refinery process flow chart.