MAJOR REFINERY PRODUCTS.
1.
Gasoline. The most important refinery product is motor gasoline, a blend
of hydrocarbons with boiling ranges from ambient temperatures to about 400 °F.
The important qualities for gasoline are octane number (antiknock), volatility
(starting and vapor lock), and vapor pressure (environmental control).
Additives are often used to enhance performance and provide protection against
oxidation and rust formation.
2.
Kerosene. Kerosene is a refined middle-distillate petroleum product that
finds considerable use as a jet fuel and around the world in cooking and space
heating. When used as a jet fuel, some of the critical qualities are freeze
point, flash point, and smoke point. Commercial jet fuel has a boiling range of
about 375°-525° F, and military jet fuel 130°-550° F. Kerosene, with
less-critical specifications, is used for lighting, heating, solvents, and
blending into diesel fuel.
3.
Liquified Petroleum Gas (LPG). LPG, which consists principally of propane and
butane, is produced for use as fuel and is an intermediate material in the
manufacture of petrochemicals. The important specifications for proper
performance include vapor pressure and control of contaminants.
4.
Distillate Fuels. Diesel fuels and domestic heating oils have boiling ranges of
about 400°-700° F. The desirable qualities required for distillate fuels
include controlled flash and pour points, clean burning, no deposit formation in
storage tanks, and a proper diesel fuel cetane rating for good starting and
combustion.
5.
Residual Fuels. Many marine vessels, power plants, commercial buildings and
industrial facilities use residual fuels or combinations of residual and
distillate fuels for heating and processing. The two most critical
specifications of residual fuels are viscosity and low sulfur content for
environmental control.
6.
Coke and Asphalt. Coke is almost pure carbon with a variety of uses from
electrodes to charcoal briquets. Asphalt, used for roads and roofing materials,
must be inert to most chemicals and weather conditions.
7.
Solvents. A variety of products, whose boiling points and hydrocarbon
composition are closely controlled, are produced for use as solvents. These
include benzene, toluene, and xylene.
8.
Petrochemicals. Many products derived from crude oil refining, such as ethylene,
propylene, butylene, and isobutylene, are primarily intended for use as
petrochemical feedstock in the production of plastics, synthetic fibers,
synthetic rubbers, and other products.
9.
Lubricants. Special refining processes produce lubricating oil base stocks.
Additives such as demulsifiers, antioxidants, and viscosity improvers are
blended into the base stocks to provide the characteristics required for motor
oils, industrial greases, lubricants, and cutting oils. The most critical
quality for lubricating-oil base stock is a high viscosity index, which
provides for greater consistency under varying temperatures.
COMMON REFINERY CHEMICALS.
1.
Leaded Gasoline Additives. Tetraethyl lead (TEL) and tetramethyl lead
(TML) are additives formerly used to improve gasoline octane ratings but are no
longer in common use except in aviation gasoline.
2.
Oxygenates. Ethyl tertiary butyl ether (ETBE), methyl tertiary butyl ether
(MTBE), tertiary amyl methyl ether (TAME), and other oxygenates improve
gasoline octane ratings and reduce carbon monoxide emissions.
3.
Caustics. Caustics are added to desalting water to neutralize acids and
reduce corrosion. They are also added to desalted crude in order to reduce the
amount of corrosive chlorides in the tower overheads. They are used in some
refinery treating processes to remove contaminants from hydrocarbon streams.
4. Sulfuric Acid and
Hydrofluoric Acid. Sulfuric acid and hydrofluoric acid are used primarily as catalysts in
alkylation processes. Sulfuric acid is also used in some treatment processes.