Oil job Gas work|Oil|Gas

asphalt	a brownish black solid or semisolid mixture of hydrocarbons and other materials obtained from native deposits or as a petroleum byproduct, used in paving, roofing, and waterproofing.
barrel	standard unit of measure for crude oil and refined products. A barrel is equal to 42 gallons (not 55).
capital project	the construction of a new processing unit (or the significant expansion of an existing unit). Capital projects are undertaken based on expected economic return or to comply with regulations. Compare turnaround.
cat feed	those products of the crude distillation process which are further refined through catalytic cracking.
catalyst	a chemical which, under certain conditions, stimulates a chemical reaction (i.e. molecular change) in another compound without being consumed in the reaction.
catalytic cracking	a refining process by which certain crude cuts are broken down or "cracked" into simpler hydrocarbon compounds at the molecular level by means of extreme heat, pressure, and exposure to a chemical catalyst. Essentially, the process changes the long chain hydrocarbon molecules of less valuable crude components into more valuable shorter chain compounds. Compare reforming.
coke	a solid material similar to coal that can be produced from processing of heavy oil.
coking	a refining process by which the denser, heavier products of the distillation process (residuals) are converted to lighter products such as cat feed and naphtha, and petroleum coke, a solid, coal like fuel. The coking unit, or "coker," heats hydrocarbons to near 800 degrees Fahrenheit, at which temperature all the lighter products vaporize, and the coke solidifies in a large drum (called a "coke drum"), from which it is removed by means of high pressure jets of water.
cooling tower	a structure which cools heated refining process water by circulating the water through a series of louvers and baffles through which cool air is forced by large fans.
crude oil	a mixture of thousands of chemicals and compounds, primarily hydrocarbons. Crude oil must be broken down into its various components by distillation before these chemicals and compounds can be used as fuels or converted to more valuable products. Crude oil is classified as either "sweet crude" (sulfur content less than 0.5 percent) or "sour crude," (at least 2.5 percent sulfur). Most of the crude CITGO processes is sour crude, from Venezuela and Mexico.
crude unit	the refinery processing unit where initial crude oil distillation takes place. See topping.
cut	one or more crude oil compounds which vaporize (and are extracted) within a certain temperature range during the crude distillation process. See distillation curve.
distillation	the first step in the refining process. During distillation, crude oil is heated in the base of a distillation tower. As the temperature increases, the crude's various compounds vaporize in succession at their various boiling points, then rise to prescribed levels within the tower (according to their densities), condense in distillation trays and are drawn off individually for further refining. Distillation is also used at other points in the refining process to remove impurities.
distillation curve	a graph which plots the percentage (by volume) of a given grade of crude which boils off as a function of temperature. Since the boiling points of the various crude cuts are constant, the distillation curve shows the percentage of each compound in a given grade or batch of crude.
distillation tower	a tall, column like vessel in which crude oil is heated and its vaporized components distilled by means of distillation trays. Also used to remove impurities added during the refining process.
drum cycle	in the petroleum coking process, the length of time it takes to 1) heat the coke drum sufficiently to safely introduce hot hydrocarbons, 2) transform the raw material into solid petroleum coke, and 3) remove or "cut" the solid coke from the drum before repeating the process. The shorter the drum cycle, the more economical the coke manufacturing process.
exchanger (or heat exchanger)	any device used to transfer heat from one process liquid to another. In one kind of exchanger, process hydrocarbons are circulated through tubes surrounded by cooling air or water, very much like in an automobile radiator.
fractionation	the separation of crude oil into its more valuable and usable components through distillation.
gravity	a property of a material that compares its weight to its volume.
heat exchanger	a piece of equipment used for transferring heat from one liquid to another.
hydrocarbons	chemical compounds composed of various combinations of hydrogen and carbon atoms. Crude oil is primarily a mixture of hydrocarbon compounds.
light oils	gasolines and fuel oils. Compare lubes.
lock	out a safety process by which operators and maintenance craftspeople ensure that equipment to be repaired in place is isolated from electrical energy and process streams.
lubes (or lubricants)	denser, more viscous refined products such as motor oil, bearing grease or machine oil.
maintenance	the process of repairing refining process equipment upon failure, and of routinely refurbishing and renewing equipment to prevent failure. Preventive maintenance is facilitated by failure analysis to devise design improvements, and the use of diagnostic instrumentation to anticipate potential problems. Day maintenance activities are commonly termed "routine" maintenance. Compare turnaround.
MTBE (methyl tertiary butyl ethane)	a gasoline additive which increases octane rating.
MTBF (mean time between failures)	the average service life of a piece of process equipment, particularly for rotating equipment. A refinery's MTBF is one indicator of the effectiveness of its maintenance program.
petrochemicals	chemicals produced from petroleum. They are often manufactured as part of the refining process. Propylene, cumene and xylene are among the petrochemicals manufactured at CITGO's refineries.
petroleum	another word for crude oil, it is a liquid hydrocarbon mixture found underground that can be refined into useful products like gasoline and motor oils.
process safety	those procedures and measures put in place to ensure that refining processes remain contained in the process stream. Process safety protects employees, the community and the environment from the potential hazards of a hydrocarbon release.
reboiler	a special kind of heat exchanger used to put heat into a distillation column.
reforming	a refining process wherein short chain molecules in certain crude distillation products are chemically recombined (reformed) by means of heat, pressure, and, usually, catalytic reaction to form higher value long chain molecule compounds.
reliability	the likelihood of a given piece of process equipment to remain in service for the expected duration.
RFG (reformulated gasoline)	lower sulfur fuels mandated by the federal government for certain U.S. metropolitan areas with high levels of combustion elated air pollution. CITGO is a major supplier of RFG.
rotating equipment	process equipment, such as pumps, motors and turbines, the function of which is based on rotational motion. Such equipment, which makes up the largest contingent of refinery hardware (numerically), is particularly susceptible to component wear, and, consequently, constitutes perhaps the primary maintenance issue in a refinery.
sedimentary	crude oil is found in this type of rock.
sour crude	crude oil containing a substantial amount of sulfur.
TAME (tertiary amyl methyl ethane)	a gasoline additive which increases octane rating.
topping	(or atmospheric distillation) the initial transformation of the crude oil at a refinery. The "topper" heats crude oil at atmospheric pressure to accomplish the first rough distillation "cut." The lighter products produced in this process are further refined in the catalytic cracking unit or the reforming unit. Heavier products which cannot be vaporized and separated in this process are distilled still further in the vacuum distillation unit or the coker.
tray	flat, perforated "shelves" at prescribed levels in a distillation tower, which allow specific vaporized crude oil components to pass through and then condense on their surfaces (after contacting domes called "bubble caps" above the perforations) before being drawn off for further distillation.
turnaround	scheduled large scale maintenance activity wherein an entire process unit is taken offstream for an extended period for comprehensive revamp and renewal.
UDC (utilized daily capacity)	daily average portion of a refinery's rated throughput capacity utilized for a given period. The closer the UDC is to the refinery's rated capacity, the more efficient the refinery is.
vacuum distillation	process by which heavier cuts of crude not vaporized in the topping (atmospheric distillation) process are heated in a vaccum to accomplish their fractionation.
viscosity	the ability of a liquid to flow at a given temperature.
volatility	the ability of a liquid to evaporate.

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