The petroleum industry began with the successful drilling of the first commercial oil well in 1859, and the opening of the first refinery two years later to process the crude into kerosene. The evolution of petroleum refining from simple distillation to today's sophisticated processes has created a need for health and safety management procedures and safe work practices. To those unfamiliar with the industry, petroleum refineries may appear to be complex and confusing places. Refining is the processing of one complex mixture of hydrocarbons into a number of other complex mixtures of hydrocarbons. The safe and orderly processing of crude oil into flammable gases and liquids at high temperatures and pressures using vessels, equipment, and piping subjected to stress and corrosion requires considerable knowledge, control, and expertise.

Safety and health professionals, working with process, chemical, instrumentation, and metallurgical engineers, assure that potential physical, mechanical, chemical, and health hazards are recognized and provisions are made for safe operating practices and appropriate protective measures. These measures may include hard hats, safety glasses and goggles, safety shoes, hearing protection, respiratory protection, and protective clothing such as fire resistant clothing where required. In addition, procedures should be established to assure compliance with applicable regulations and standards such as hazard communications, confined space entry, and process safety management.

This chapter of the technical manual covers the history of refinery processing, characteristics of crude oil, hydrocarbon types and chemistry, and major refinery products and by-products. It presents information on technology as normally practiced in present operations. It describes the more common refinery processes and includes relevant safety and health information. Additional information covers refinery utilities and miscellaneous supporting activities related to hydrocarbon processing. Field personnel will learn what to expect in various facilities regarding typical materials and process methods, equipment, potential hazards, and exposures.

The information presented refers to fire prevention, industrial hygiene, and safe work practices, and is not intended to provide comprehensive guidelines for protective measures and/or compliance with regulatory requirements. As some of the terminology is industry-specific, a glossary is provided as an appendix. This chapter does not cover petrochemical processing.

OVERVIEW OF THE PETROLEUM INDUSTRY

BASIC REFINERY PROCESS: DESCRIPTION AND HISTORY. Petroleum refining has evolved continuously in response to changing consumer demand for better and different products. The original requirement was to produce kerosene as a cheaper and better source of light than whale oil. The development of the internal combustion engine led to the production of gasoline and diesel fuels. The evolution of the airplane created a need first for high-octane aviation gasoline and then for jet fuel, a sophisticated form of the original product, kerosene. Present-day refineries produce a variety of products including many required as feedstock for the petrochemical industry.

Distillation Processes. The first refinery, opened in 1861, produced kerosene by simple atmospheric distillation. Its by-products included tar and naphtha. It was soon discovered that high-quality lubricating oils could be produced by distilling petroleum under vacuum. However, for the next 30 years kerosene was the product consumers wanted. Two significant events changed this situation: (1) invention of the electric light decreased the demand for kerosene, and (2) invention of the internal combustion engine created a demand for diesel fuel and gasoline (naphtha).

Thermal Cracking Processes. With the advent of mass production and World War I, the number of gasoline-powered vehicles increased dramatically and the demand for gasoline grew accordingly. However, distillation processes produced only a certain amount of gasoline from crude oil. In 1913, the thermal cracking process was developed, which subjected heavy fuels to both pressure and intense heat, physically breaking the large molecules into smaller ones to produce additional gasoline and distillate fuels. Visbreaking, another form of thermal cracking, was developed in the late 1930's to produce more desirable and valuable products.

 

TABLE IV: 2-1. HISTORY OF REFINING

Year Process name Purpose By-products, etc. 1862 Atmospheric distillation Produce kerosene Naphtha, tar, etc. 1870 Vacuum distillation Lubricants (original) Cracking feedstocks (1930's) Asphalt, residual coker feedstocks 1913 Thermal cracking Increase gasoline Residual, bunker fuel 1916 Sweetening reduce sulfur & odor Sulfur 1930 Thermal reforming Improve octane number Residual 1932 Hydrogenation Remove sulfur Sulfur 1932 Coking Produce gasoline basestocks Coke 1933 Solvent extraction Improve lubricant viscosity index Aromatics 1935 Solvent dewaxing Improve pour point Waxes 1935 Cat. polymerization Improve gasoline yield & octane number Petrochemical feedstocks 1937 Catalytic cracking Higher octane gasoline Petrochemical feedstocks 1939 Visbreaking reduce viscosity Increased distillate,tar 1940 Alkylation Increase gasoline octane & yield High-octane aviation gasoline 1940 Isomerization Produce alkylation feedstock Naphtha 1942 Fluid catalytic cracking Increase gasoline yield & octane Petrochemical feedstocks 1950 Deasphalting Increase cracking feedstock Asphalt 1952 Catalytic reforming Convert low-quality naphtha Aromatics 1954 Hydrodesulfurization Remove sulfur Sulfur 1956 Inhibitor sweetening Remove mercaptan Disulfides 1957 Catalytic isomerization Convert to molecules with high octane number Alkylation feedstocks 1960 Hydrocracking Improve quality and reduce sulfur Alkylation feedstocks 1974 Catalytic dewaxing Improve pour point Wax 1975 Residual hydrocracking Increase gasoline yield from residual Heavy residuals