Key Terms |
Definition |
Atmospheric Crude Oil Distillation Capacity |
The refining process of separating crude oil components at atmospheric pressure by heating to
temperatures of about 600º to 750º F (depending on the nature of the crude oil and
desired products) and subsequent condensing of the fractions by cooling.
|
Barrel |
A unit of volume equal to 42 U.S. gallons.
|
Barrels Per Calendar Day |
The amount of input that a distillation facility can process under usual operating conditions.
The amount is expressed in terms of capacity during a 24-hour period and reduces the maximum
processing capability of all units at the facility under continuous operation
(see Barrels per Stream Day) to account for the following limitations that may delay, interrupt,
or slow down production:
the capability of downstream facilities to absorb the output of crude oil processing
facilities of a given refinery. No reduction is made when a planned distribution of
intermediate streams through other than downstream facilities is part of a refinery's normal operation;
the types and grades of inputs to be processed;
the environmental constraints associated with refinery operations;
the reduction of capacity for scheduled downtime due to such conditions as routine
inspection, maintenance, repairs, and turnaround; and
the reduction of capacity for unscheduled downtime due to such conditions as
mechanical problems, repairs, and slowdowns.
|
Barrels Per Stream Day |
The maximum number of barrels of input that a distillation facility can process within a
24-hour period when running at full capacity under optimal crude and product slate conditions
with no allowance for downtime.
|
Catalytic Cracking |
The refining process of breaking down the larger, heavier, and more complex hydrocarbon
molecules into simpler and lighter molecules. Catalytic cracking is accomplished by the
use of a catalytic agent and is an effective process for increasing the yield of gasoline
from crude oil. Catalytic cracking processes fresh feeds and recycled feeds.
|
Catalytic Cracking - Fresh Feeds |
Crude oil or petroleum distillates which are being fed to processing units for the first time.
|
Catalytic Cracking - Recycled Feeds |
Feeds that are continuously fed back for additional processing.
|
Catalytic Hydro-Cracking |
A refining process that uses hydrogen and catalysts with relatively low temperatures and
high pressures for converting middle boiling or residual material to high-octane gasoline,
reformer charge stock, jet fuel, and/or high grade fuel oil. The process uses one or more
catalysts, depending upon product output, and can handle high sulfur feedstocks without
prior desulfurization.
|
Catalytic Hydrotreating |
A refining process for treating petroleum fractions from atmospheric or
vacuum distillation units (e.g., naphthas, middle distillates, reformer
feeds, residual fuel oil, and heavy gas oil) and other petroleum (e.g.,
cat cracked naphtha, coker naphtha, gas oil, etc.) in the presence of
catalysts and substantial quantities of hydrogen. Hydrotreating includes
desulfurization, removal of substances (e.g., nitrogen compounds) that
deactivate catalysts, conversion of olefins to paraffins to reduce gum
formation in gasoline, and other processes to upgrade the quality of the
fractions.
|
Catalytic Reforming |
A refining process using controlled heat and pressure with catalysts to
rearrange certain hydrocarbon molecules, thereby converting paraffinic and
naphthenic type hydrocarbons (e.g., low-octane gasoline boiling range
fractions) into petrochemical feedstocks and higher octane stocks
suitable for blending into finished gasoline. Catalytic reforming is
reported in two categories:
Low Pressure. A processing unit operating at less than 225 pounds
per square inch gauge (PSIG) measured at the outlet separator.
High Pressure. A processing unit operating at either equal or greater
than 225 pounds per square inch gauge (PSIG) measured at the outlet
separator.
|
Charge Capacity |
The input (feed) capacity of the refinery processing facilities.
|
Crude Oil |
A mixture of hydrocarbons that exists in liquid phase in natural underground
reservoirs and remains liquid at atmospheric pressure after passing through
surface separating facilities. Depending upon the characteristics of the crude
stream, it may also include:
Small amounts of hydrocarbons that exist in gaseous phase in natural
underground reservoirs but are liquid at atmospheric pressure after being
recovered from oil well (casinghead) gas in lease separators and are subsequently
commingled with the crude stream without being separately measured. Lease
condensate recovered as a liquid from natural gas wells in lease or field
separation facilities and later mixed into the crude stream is also included;
Small amounts of nonhydrocarbons produced with the oil, such as sulfur and
various metals;
Drip gases, and liquid hydrocarbons produced from tar sands, oil sands,
gilsonite, and oil shale.
Liquids produced at natural gas processing plants are excluded. Crude oil is refined to produce
a wide array of petroleum products, including heating oils; gasoline, diesel and jet fuels;
lubricants; asphalt; ethane, propane, and butane; and many other products used for their
energy or chemical content.
|
Delayed Coking |
A process by which heavier crude oil fractions can be thermally decomposed under conditions
of elevated temperatures and pressure to produce a mixture of lighter oils and petroleum coke.
The light oils can be processed further in other refinery units to meet product specifications.
The coke can be used either as a fuel or in other applications such as the manufacturing of
steel or aluminum.
|
Desulfurization |
The removal of sulfur, as from molten metals, petroleum oil, or flue gases.
Petroleum desulfurization is a process that removes sulfur and its compounds
from various streams during the refining process. Desulfurization processes
include catalytic hydrotreating and other chemical/physical processes such
as absorption. Desulfurization processes vary based on the type of stream
treated (e.g. naphtha, distillate, heavy gas oil, etc.) and the amount of
sulfur removed (e.g. sulfur reduction to 10 ppm).
|
Distillate Fuel Oil |
A general classification for one of the petroleum fractions produced in conventional distillation
operations. It includes diesel fuels and fuel oils. Products known as No. 1, No. 2, and
No. 4 diesel fuel are used in on-highway diesel engines, such as those in trucks and automobiles,
as well as off-highway engines, such as those in railroad locomotives and agricultural machinery.
Products known as No. 1, No. 2, and No. 4 fuel oils are used primarily for space heating and
electric power generation.
|
Flexicoking |
A thermal cracking process which converts heavy hydrocarbons such as
crude oil, tar sands bitumen, and distillation residues into light
hydrocarbons. Feedstocks can be any pumpable hydrocarbons including
those containing high concentrations of sulfur and metals.
|
Fluid Coking |
A thermal cracking process utilizing the fluidized-solids technique to remove carbon (coke)
for continuous conversion of heavy, low-grade oils into lighter products. |
Fuels Solvent Deasphalting |
A refining process for removing asphalt compounds from petroleum fractions,
such as reduced crude oil. The recovered stream from this process is used
to produce fuel products.
|
Gas Oil |
A liquid petroleum distillate having a viscosity intermediate
between that of kerosene and lubricating oil. It derives its name from
having originally been used in the manufacture of illuminating gas. It is
now used to produce distillate fuel oils and gasoline.
|
Heavy Gas Oil |
Petroleum distillates with an approximate boiling range
from 651º F to 1000º F.
|
Idle Capacity |
The component of operable capacity that is not in operation and not under active repair, but
capable of being placed in operation within 30 days; and capacity not in operation but under
active repair that can be completed within 90 days.
|
Kerosene |
A light petroleum distillate that is used in space heaters, cook stoves, and water heaters
and is suitable for use as a light source when burned in wick-fed lamps. Kerosene has a
maximum distillation temperature of 400 degrees Fahrenheit at the 10-percent recovery point,
a final boiling point of 572 degrees Fahrenheit, and a minimum flash point of 100 degrees
Fahrenheit. Included are No. 1-K and No. 2-K, the two grades recognized by ASTM Specification
D 3699 as well as all other grades of kerosene called range or stove oil, which have properties
similar to those of No. 1 fuel oil. See Kerosene-Type Jet Fuel.
|
Kerosene-Type Jet Fuel |
A kerosene-based product having a maximum distillation temperature of 400 degrees Fahrenheit at
the 10-percent recovery point and a final maximum boiling point of 572 degrees Fahrenheit
and meeting ASTM Specification D 1655 and Military Specifications MIL-T-5624P and MIL-T-83133D
(Grades JP-5 and JP-8). It is used for commercial
and military turbojet and turboprop aircraft engines.
|
Naphtha |
A generic term applied to a petroleum fraction with an approximate boiling range between
122º and 400º F.
|
No. 2 Diesel Fuel |
A distillate fuel oil that has a distillation temperature of 640 degrees
Fahrenheit at the 90-percent recovery point and meets the specifications
defined in ASTM Specification D 975. It is used in high-speed diesel
engines that are generally operated under uniform speed and load conditions,
such as those in railroad locomotives, trucks, and automobiles.
|
Operable Capacity |
The amount of capacity that, at the beginning of the period, is in operation; not in operation
and not under active repair, but capable of being placed in operation within 30 days; or not
in operation but under active repair that can be completed within 90 days. Operable capacity
is the sum of the operating and idle capacity and is measured in barrels per calendar day or
barrels per stream day.
|
Operating Capacity |
The component of operable capacity that is in operation at the beginning of the period.
|
Petroleum Administration for Defense (PAD) Districts |
Geographic aggregations of the 50 States and the District of Columbia into five districts
by the Petroleum Administration for Defense in 1950. These districts were originally defined
during World War II for purposes of administering oil allocation.
Description and maps of PAD Districts and Refining Districts.
|
Refinery |
An installation that manufactures finished petroleum products from crude oil, unfinished oils,
natural gas liquids, other hydrocarbons, and oxygenates.
|
Residual Fuel Oil |
A general classification for the heavier oils, known as No. 5 and No. 6 fuel oils, that remain
after the distillate fuel oils and lighter hydrocarbons are distilled away in refinery operations.
It conforms to ASTM Specifications D396 and D975 and Federal Specification VV-F-815C.
No. 5, a residual fuel oil of medium viscosity, is also known as Navy Special and is defined in
Military Specification MIL-F-859E, including Amendment 2 (NATO Symbol F-770). It is used in
steam-powered vessels in government service and inshore powerplants. No. 6 fuel oil includes
Bunker C fuel oil and is used for the production of electric power, space heating, vessel
bunkering, and various industrial purposes.
|
Thermal Cracking |
A refining process in which heat and pressure are used to break down,
rearrange, or combine hydrocarbon molecules. Thermal cracking includes
gas oil, visbreaking, fluid coking, delayed coking, and other thermal
cracking processes (e.g., flexicoking).
|
Vacuum Distillation |
Distillation under reduced pressure (less the atmospheric) which lowers
the boiling temperature of the liquid being distilled. This technique
with its relatively low temperatures prevents cracking or decomposition
of the charge stock.
|
Visbreaking |
A thermal cracking process in which heavy atmospheric or vacuum-still
bottoms are cracked at moderate temperatures to increase production
of distillate products and reduce viscosity of the distillation residues.
|