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Show Another source was a survey of petrolewn industry research needs recently conducted by Energy and Environmental Research Corporation (EER). EER has participated directly in this research needs evaluation effort and has conducted combustion research for govenmlent agencies (including DOE and EPA), petroleum companies, and trade associations, including the Western States Petroleum Association (WSPA) and the Petroleum Environmental Research Forum (PERF), for several years. Results of this survey are summarized in this section. The survey included not only petroleum refinery companies but also companies that depend on and are knowledgeable of petroleum industry research needs. These included natural gas distribution companies (Southern California Gas and Pacific Gas and Electric), combustion and heating equipment manufacturers for the refinery industry (process furnace manufacturers-KTI and burner manufacturers, Selas and John Zink), a nwnber of refinery end users, both corporate and plant engineering and the architectural and engineering finns who support them (Fluor, Brown & Root, and C.F. Braun). Trade associations such as the American Petroleum Institute (API), WSPA, and PERF were also important sources of data. The survey included a questionnaire used with a limited but diverse subset of the population surveyed. Nineteen potential interviewees were identified and contacted. R&D for improved process control (sensors), emissions (acid gas and air toxic) control, and enhanced heat transfer through improved convective and radiative heat transfer were explored. Generic petroleum industry combustion equipment that processes significant amounts of product and/or consumes large quantities of fuel was identified. 4.1.1 About the Industry Refineries vary quite widely in crude feed characteristics, complexity, and product mix. Most large refineries produce a high yield of gasoline and middle distillate fuel and lube oil from crude oil. The most energy intensive refinery unit operations include initial crude distillation, desulfurization of some of the intermediate products, and their upgrading through catalytic cracking, naphtha refornling, alk-ylation, and coking. Sources of energy for these operations are primarily natural gas, refinery fuel gas, and petroleum coke. These operations account for more than 80% of the energy conswned. The distillation of crude requires fluid heating in a process heater to about 800°F. Crude separation via distillation into intemlediate products varies, but typically results in high and low sulfur liquids, gases, and off gas. Sulfur typically concentrates in the liquids and residuum, whieh need to be further upgraded in additional unit operations. Natural gas and refinery gas blends are bWl1ed in crude heaters to supply process heat to the column feeds. Steam produced in boilers is used to provide heat and stripping media to various components of the distillation equipment. Catalytic hydrogenation of the sulfur-containing liquids (naphtha and gas oil) requires H2 addition and heating to between 650 and 800°F in a process heater. The feed is then passed through a fixed bed catalytic reactor, producing desulfurized liquid streams and H2S off gas. H2 is produced on-site through purification of off gas from catalytic cracking and reforming of crude feedstocks, or through catalytic refonning of a fossil fuel, usually natural gas. H2 reforming requires large furnaces that incorporate both concurrent process heating and catalytic cracking of the feed at moderately high temperatures of about 1,600°F. Large amounts of steam are co-fed and used in downstream shift reactors to improve H2 yield. Refinery gas and natural gas are usually used as furnace and boiler fuels. Coking of the low-end cut distillates such as residuum is performed to improve gasoline yields. Coker products include coke, olefins, gas oils, and naphtha, which must be further processed or sold as intermediate product. Coker feed is reheated in a process heater firing refinery fuels and off gases. Catalytic reforming upgrades nonaromatics and napthas to aromatics for octane improvement. The unit operations of catalytic cracking and alk-ylation further upgrade feedstock intermediates. They are less energy intensive than crude heating, requiring heating feed from low to moderate temperatures in a process heater train. Catalytic refonning wlit operations include (a) catalytic cracking where gas, oil, and catalyst are mixed, heated to about 900°F and reacted. The components separated through distillation, and (b) alk-ylation where isobutane reacts to fonn olefin steams over a catalyst. Typical large fuel burning combustion equipment includes (a) process heaters providing heated fluids to unit operations such as distillation, refonning, cracking, and hydro treating, (b) large boilers providing process and heat steam, high pressure, superheated steam to turbine drives, and in some refmeries gas turbines operating in cogeneration configurations providing power, steam, and process heat. All of this equipment can flfe a wide range of gaseous and liquid fuels, usually blends of process 0[[ gases of widely varying heating value and more traditional fossil fuels . 5 |