| ASTM: |
Initials of American Society
for Testing Materials, an organization which sets standards for the
testing of industrial products. |
| Absorption: |
The process by which one
substance attracts another, forming a homogeneous mixture. Oil absorbs
natural gasoline from wet natural gas. Caustic absorbs hydrogen sulphide
from hydrocarbon vapors. |
| Additive: |
A substance added to
petroleum products to impart some desirable property. |
| Adsorption: |
The process by which one
substance attracts another, forming a physical or chemical bond at its
surface. |
| Agitator: |
A cone bottom tank for
treating oils equipped with air or gas spargers for mixing. |
| Air-Blowing: |
A process for raising the
softening point of an asphalt by reacting with air at elevated
temperature. |
| Alkylate: |
The product of an alkylation
process. |
| Alkylation: |
Process of combining an
olefin with an isoparaffin to form an isoparaffin of higher molecular
weight. Also, combining an olefin with an aromatic to form
alkyl-benzene. |
| API: |
Initials of American
Petroleum Institute. |
| API Gravity: |
A special gravity scale
adopted by the API for expressing gravities of petroleum products. |
| Aromatic: |
Unsaturated ring structured
hydrocarbon molecule. |
| Asphalt: |
Black to dark brown solid or
semisolid bituminous material which gradually liquifies when heated,
produced from distillation residues of crude petroleum, or occuring
naturally. |
| Asphaltenes: |
One of the principal
components of asphalt. It is the black or brown solid material
precipitated from an asphalt with normal pentane. It is an arbitrary
fraction defined by the method of analysis. Other arbitrary fractions of
asphalt are oils and resins. |
| Assay: |
The tabulated results of a
comprehensive laboratory analysis of crude oil. |
| Barrel: |
The standard unit of
measurement in the petroleum industry. It contains 42 US standard
gallons, 35 imperial gallons. (BPD - Barrels Per Day). |
| Base Oil: |
A finished petroleum stock
which is blended with other materials to make salable products. |
| Bitumen: |
Hydrocarbon material of
natural or pyrogenous origin, or combination of both, accompanied by
nonmetallic derivatives, which may be gaseous, liquid, semisolid or
solid, and which is completely soluble in carbon disulphide. (ASTM D
8-63). |
| Blanket Gas: |
Gas introduced above a liquid
in a vessel to keep out air to prevent oxidation of the material, or to
prevent forming explosive mixtures. |
| Blending: |
Mixing two or more materials
together. |
| Blind: |
A steel plate inserted
between a pair of flanges to prevent flow through a line. |
| Bloom: |
The colour of an oil observed
by reflected light. |
| Blowdown: |
Withdrawal of water from
boilers and cooling towers to prevent buildup of solids. |
| Bottoms: |
Residue remaining in a still
after distillation. Tank bottoms refers to water and sediment in the
tank. |
| BS and W: |
Bottoms sediment and water
measured in a crude oil by centrifuging a sample. Sometimes abbreviated
to S and W. |
| Bright Stock: |
High viscosity, refined, and
dewaxed lubrication oil base stock, usually produced by suitable
treatment of petroleum residues. |
| By-Products: |
Useful materials recovered
incidental to the principal objective of refining petroleum. |
| Catalyst: |
Material which promotes a
chemical reaction but remains unchanged itself, or can be regenerated to
its original form. |
| Catalytic Cracking: |
A process in which large
molecules are broken down into smaller molecules by the use of heat,
pressure, and catalyst. |
| Catalytic Desulphurization: |
A process in which the
sulphur content of petroleum is reduced, usually by conversion to H2S,
using a catalyst with or without the presence of added hydrogen. |
| Catalytic Reforming: |
A process which naphthenes
are converted to romatics by removal of hydrogen in the presence of a
catalyst. |
| Chromatograph: |
An apparatus for analyzing
mixtures of compounds by separating them into individual components
which can be identified by colour or other means. |
| Clay: |
Granular or finely divided
mineral material used for treating pertroleum. Thisi s a general term
including fuller's earth, bauxite, bentonite, and montmorillonite. |
| Compounding: |
Mixing additives with oils,
particularly lubes, to impart oxidation resistance, rust resistance,
detergency. |
| Condensate: |
- Liquid condensed from the vapours
leaving the top of a distillation column.
- Condensed steam.
- Petroleum liquids separated from wet
natural gas by cooling at elevated pressure.
- Petroleum liquids produced from
certain wells by reducing the pressure of a supercritical gas
mixture. (Retrograde condensation).
|
| Cracked Naphtha: |
The crude low boiling product
from the thermal cracking process, from which gasoline is made by
distillation. |
| Cracked Tar: |
Residue from the thermal
cracking process. |
| Crude: |
A short name for raw or
unrefined petroleum. Crude oil. |
| Cut: |
A fraction; a part of the
whole, e.g., the gasoline cut from raw crude oil. |
| Cutback Asphalt: |
Asphalt blended with
gasoline, kerosene, or heavier distillate for ease of handling during
application, e.g. road oils. |
Cutter/
Cutter Stock: |
A low viscosity petroleum
stock used to reduce the viscosity of heavy, very viscous materials such
as asphalts and cracked tars. Light cycle oil is an example. |
| Cycle Stock: |
Material taken from a latter
stage of a process and recharged to the process at some earlier stage.
Light cycle oil, a fraction of the synthetic crude produced in the
catalytic cracking process, which is returned to the reactor is an
example. |
| Cylinder Stock: |
Oil used for lubrication of
steam cylinders, usually a high viscosity distillate. |
| Demulsification: |
Process of
"breaking" or separating an emulsion into its component parts. |
| Demulsifier: |
An additive which promotes
demulsification. |
| Deoiling |
The process of making an
oil-free wax from a waxy stock, comprising chilling mixture of solvent
and feed to crystallize part of the wax, and separating the wax from the
waxy-oil-solvent by filtering or centrifuging. |
| Desalting: |
The process of removing salt
from crude by emulsification with water, then breaking the emulsion and
separating phases. |
| Dewaxing: |
The process of making a
wax-free oil from a waxy stock, comprising chilling a mixture of solvent
and feed to a low temperature to crystallize all of the wax and
separating the wax cake (slack wax) by filtering or centrifuging. |
| Dew Point: |
Temperature at which a
mixture of gases reaches saturation conditions for one or more of the
components and condensation begins. |
| Doc Text/Doctor Test: |
A qualitative analytical test
for mercaptans comprising mixing a sample of gasoline or heavier
distillate with Doctor solution (sodium plumbite, a solution of litharge
in caustic) and adding a little finely divided sulphur. If the yellow
colour of the sulphur is darkened, mercaptans are present and the text
is reported "positive". A positive result is also called a
"bad Doc". A negative result may be reported "Doc
sweet". |
| Doctor Treatment: |
The process of sweetening
gasoline or heavier distillates by converting mercaptans to disulphides,
using sodium plumbite, sulphur, and air. |
Downcomer/
Downspout: |
That part of a distillation
column tray in which liquid is separated from the froth and flows by
gravity to a tray below. |
| Draw/Draw-Off: |
A pipe connection (usually
valved) to a vessel through which liquid can flow. Examples: A side cut
draw on a distillation column. A water draw on a tank. |
| Dry Gas: |
A hydrocarbon gas consisting
mainly of methane and ethane and containing no recoverable amounts of
butane or heavier hydrocarbons. |
| EP/End Point: |
The highest temperature
indicated by the thermometer in a distillation test of an oil. |
| Extract: |
In a solvent extraction
process, it is the material preferentially dissolved by the solvent. |
| Extraction: |
A process of separating a
material by means of a partially miscible solvent into a fraction which
is soluble in the solvent and a fraction which is relatively insoluble. |
| Fixed Gas: |
Gas which will not condense
under the pressure and temperature conditions available in a process. |
| Flash Point: |
The lowest temperature at
which an oil gives off vapor in sufficient quantity to burn momentarily
on the approach of a flame or spark. |
| Flash Tower: |
A vessel used for separation
of liquid a vapor in a flash distillation process. |
| Flashing: |
The process of separating
products by reducing the pressure on a hot oil as it enters a vessel.
The light fractions vaporize (flash off) while the liquid drops to the
bottom. |
| Flood/Flooding: |
A spewing or heaving of
liquid along with vapor out of the top of a distillation column. It is
caused by excessive liquid and/or vapor flow in the column. |
| Flux/Flux Oil: |
- A liquid residuum from asphaltic
crude.
- An oil for blending with asphalt for
the purpose of softening it or preparing it for air blowing.
|
| Fuel Gas: |
Light gas by-products from
refining operations which are used to fuel process furnaces. |
| Fuel Oil: |
A general term which is
applied to any oil used for the production of power and heat. For a
description of classes of fuels, see ASTM D 288. |
| Furnace: |
A term applied to oil and/or
gas-fired heaters use in refinery processes. |
| Gas Blanket: |
An atmosphere of inert gas
applied to the vapor space of a vessel to prevent oxidation of its
contents and/or prevent an explosive mixture from forming. |
| Gasoline, Cracked: |
The principle product of
catalytic cracking and thermal cracking processes. |
| Gasoline, Natural: |
Liquid product recovered from
wet natural gas by absorption, compression, or refrigeration. |
| Gasoline, Polymer: |
Product of polymerization of
normally gaseous olefins to hydrocarbons boiling in the gasoline range. |
| Gasoline, Straight Run: |
One of the products obtained
by distillation of petroleum. |
| Header: |
- A common line to which two or more
lines are joined.
- A U-bend connection between two
consecutive tubes in a heater coil.
|
| Heater: |
The furnace and tube
arrangement which furnishes heat for a process. |
| Hydrocarbon: |
Compounds of carbon and
hydrogen. Crude oil is a complex mixture of hydrocarbon compounds. |
| Hydrocracking: |
A process in which large
molecules are broken into smaller molecules by the use of heat,
pressure, catalyst, and hydrogen. |
| Hydrofining: |
A process for treating
petroleum with hydrogen in the presence of a catalyst under relatively
mild conditions of temperature and pressure. Some hydrocracking may
occur under more severe conditions. |
| Hydrofinishing: |
A mild hydrofining process
used particularly to replace or supplement clay treating of lube oils
and waxes. |
| Hydrogenation: |
A hydrogen treating process
in which hydrogen is added to unsaturated molecules. Olefins are
converted to paraffins, aromatics are converted to naphthenes, oxygen is
converted to water, nitrogen is converted to ammonia, and sulphur is
converted to H2S. |
IBP/
Initial Boiling Point/
Init: |
The temperature in a
laboratory distillation test indicated by the thermometer at which the
first drop of distillate falls from the condenser. |
| Isomerization: |
A process for rearranging the
atoms in a molecule so that the product has the same empirical formula,
but a different structure, e.g., converting normal butane to isobutane. |
| Lean Oil: |
Absorption oil from which
gasoline fractions have been removed, e.g., the oil leaving the stripper
in a natural gasoline plant. |
| LNG: |
Abbreviation for liquified
natural gas. |
| LPG: |
Abbreviation for liquified
petroleum gas. |
| Lube: |
Short for lubricating oil. |
| Lube Distillate: |
High boiling, 700-1000 ºF
range, petroleum distillate used for manufacture of lubricating oils. |
| Mercaptans: |
Sulphur compounds occuring
naturally in some crudes and formed in cracking operations. They are
foul smelling substances of the formula RSH where R is an alkyl group. |
| Naphtha: |
A general term applied to the
lower boiling fractions of petroleum, usually below 400 ºF. |
| Naphthene: |
A hydrocarbon containing at
least on ring structure and saturated with respect to hydrogen. |
| Naphthenic Acids: |
The organic acids occurring
naturally in petroleum. |
| Natural Gas: |
Naturally occurring light
hydrocarbons varying in composition from mostly methane to a mixture
ranging from methane through hexanes. |
| Neutral Oil: |
Lubricating oil base stock of
low and medium viscosity, genrally light in colour, and produced from
lube oil distillation or distilled from a refined and dewaxed residuum. |
Octane Number/
Rating: |
A measure of the antiknock
qualities of gasoline. Isooctane is rated at 100. Normal heptane is
rated at zero. A 50-50 mixture of these two would be rated at 50. |
| Olefins: |
Open chain hydrocarbons
containing one or more double bonds. |
| Paraffins: |
Open chain hydrocarbons
saturated with respect to hydrogen. |
Paraffin Wax/
Petroleum Wax: |
Hydrocarbons of molecular
weight higher than 250 and boiling above 600 ºF which are solid at room
temperature. Waxes are mostly straight hydrocarbons, with a small amount
of branching. They may also contain naphthene and aromatic rings. |
| Polymerization: |
The process of combining two
or more molecules to form a single large molecule. |
| Raffinate: |
A term applied to the refined
oil produced in solvent extraction processes. |
| Rectification: |
Fractional distillation
referring to the removal of low boiling hydrocarbons from gasoline to
adjust its vapor pressure. |
| Reforming: |
A process of cracking
gasoline to increase its octane number. |
| Resins: |
One of the three main
constituents of asphalt, characterized by absorption on clay. |
| Rich Oil: |
Absorption oil containing
dissolved gasoline fractions. |
| Riser: |
A pipe which allows vapor or
liquid to flow upward in a process vessel. |
| Rundown Tanks: |
Receiving tanks for products
of distillation. Also called pans. |
| Scrubbing: |
Purification of a gas by
washing it in a tower or agitator. |
| Seal Oil/Sealing Oil |
Any oil used to pump packing
glands to keep packing cool and prevent leakage of stock being
processed. |
| Sour: |
Foul smelling. Describing a
petroleum fraction having a bad odor usually caused by mercaptans. |
| Straight Run: |
A material produced directly
from crude oil by distillation. |
| Sweet: |
Having a good odor; negative
to the Doctor test. |
| Sweetening: |
A process of removing
mercaptans or converting them to disulphides. |
| Tar: |
Synonym for petroleum
residuum, either straight run or cracked. |
| Thermal Cracking: |
The process of breaking down
large molecules into smaller ones by the use of heat and pressure. |
Thermalsyphon/
Thermosyphon Reboiler |
A heat exchanger in which
circulation flow is induced in a process liquid by generating vapors
which lift the liquid back into the process vessel, thereby creating a
continuous recycle without the aid of a pump. |
| Thinners: |
Narrow boiling fractions in
the gasoline and kerosene boiling range (200 ºF to 450ºF) used as
solvents and diluents in the paint and varnish industry. |
| Topping: |
The process of distillation
in which only a fraction of the distillable portion of the feed is
removed, e.g., Topped Crude - an atmospheric column bottoms. |
| Treating: |
A general term for refining
petroleum with chemicals. |
Unsaturates/
Unsaturated Hydrocarbons |
Hydrocarbons deficient in
hydrogen, including olefins and aromatics. |
| Vacuum Distillation |
Distillation at reduced
pressure (below atmospheric pressure) with or without the use of steam. |
| Vapor |
Gaseous substance which can
be at least partly condensed by cooling or compression. |
| Vapor Binding: |
The formation of vapor in a
liquid line causing an interruption of liquid flow. |
| Vapor Lock: |
Vapor binding in the gasoline
line leading to an engine. |
| Virgin: |
A descriptive term applied to
products produced directly from crude to distinguish them from similar
products from cracking processes. |
| Visbreaking: |
A mild thermal cracking
process. |
| Viscosity: |
The resistance of a fluid to
flow when a force is exerted upon it. |
| Viscosity-Gravity
Constant: |
A useful function for
characterizing viscous fractions of petroleum. Ref. ASTM D 2501-67 |
| Viscosity Index: |
An empirical number
indicating the effect of change in temperature on the viscosity of an
oil. A high viscosity index (VI) signifies a relatively small change of
viscosity with temperature. Ref. ASTM D 2270-64. |
Wax/
Petroleum Wax: |
A product separated from
petroleum which is solid or semi-solid at 77 ºF and consists
essentially of mixture of saturated hydrocarbons. |
| Weathering: |
The process of vaporization
which occurs when crude of petroleum product is allowed to stand in an
open vessel. Also, deteriorization of a material resulting from exposure
to the atmosphere. |
| Wet Gas: |
Natural gas, or gas produced
by some refinery process, which contains recoverable gasoline fractions. |
