Abel tester - A closed-cup flash
tester for kerosene and other oils
- Total pressure equal to gauge pressure plus 14.7 lbs./sq.
in at sea level
- The ratio of air weight to fuel wight consumed in an internal
combustion engine or furnace.
Aliphatic - A
class of saturated or unsaturated carbon compounds, in which
the carbon atoms are joined in open chains.
Alkylation - A
process using sulfuric or hydrofluoric acid as a catalyst to
combine olefins and isoparaffins to produce a high-octane product
known as alkylate.
- The aniline point of a petroleum product is the minimum equilibrium
solution temperature with an equal volume of freshly distilled
API - American
API Gravity -
Gravity (weight per unit volume) of oils as measured by the
API scale. This standard was adopted by the API 5/4/22 as the
standard for the American petroleum industries
Aromatics - One
of the three principal groups or series of hydrocarbon compounds
that occurs naturally in crude oil. New formulations of gasoline
with increased octane levels often contain increased amounts
Ash - Inorganic
residue remaining after ignition of combustible substances determined
by definite prescribed methods.
Insoluble, semi-solid, or solid particles which are combustible
and are highly aromatic. Asphaltenes contain a high carbon to
hydrogen ratio and entrap water, fuel ashes and other impurities.
ASTM - American
Society for Testing Materials. Grade and quality specifications
for petroleum products are determined by ASTM test methods
- The ability of an oil to be broken up into a fine spray by
some mechanical means.
Barrel - A unit
of volume measurement used for petroleum and its products. 1
barrel = 42 U.S. gallons or 35 British gallons.
Bbl - Abbreviation
Benzene - An aromatic
hydrocarbon which is a colorless, volatile, flammable liquid.
Benzene is obtained chiefly from coal tar and is used as a solvent
for resins and fats in dye manufacture.
BHP - Brake horsepower
Blender - A device
for mixing two fuel oils to achieve a less viscous and more
Blending - Mixing
of two compatible fuels having different properties in order
to produce an intermediate fuel
(Residual) Fuel - Heavy, high sulfur and high metals
residual fuel oil left after lighter crude oil has been distilled
BS & W - Bottom
sediment and water.
BS & W Monitor
- An instrument which detects entrained water content in petroleum
products wherein the water changes the capacitive reactance
as a function of the dielectric constant.
BTU - British
Thermal Unit. The amount of heat required to raise the temperature
of 1 pound of water by 1 degree Fahrenheit.
Bunker Fuel Oil
- Heavy, residual fuel oil used in ships
Calorie - The
amount of heat required to raise the temperature of 1 gram of
water by 1 degree centigrade, at or near maximum density.
- Amount of heat produced by the complete combustion of a unit
weight of fuel. Usually expressed in calories per gram or BTU's
per pound, the latter being numerically 1.8 times the former.
Catalyst - A substance which promotes
a chemical reaction, but does not itself enter into the reaction.
Catalytic Fines Hard, abrasive crystalline particles of alumina,
silica, and/or alumina silica that can be carried over from
the fluidic catalytic cracking process of residual fuel stocks.
Particle size can range from sub-micron to greater than sixty
(60) microns in size. These particles become more common in
the higher viscosity marine bunker fuels.
Cat Cracker - A large refinery
vessel for processing reduced crudes or other feed-stocks in
the presence of a catalyst, as opposed to the older method of
thermal cracking, which employs heat and pressure only. Catalytic
cracking is generally preferred since it produces less gas and
other highly volatile byproducts. It produces a motor fuel of
higher octane than the thermal process.
- The process of breaking up heavier hydrocarbon molecules into
lighter hydrocarbon fractions by using heat and catalysts (see
Centigrade - Temperature based
on 0 for the temperature at which water freezes and 100 for
the temperature at which water boils.
Centipoise - 0.01 poise or centistokes
times specific gravity at the test temperature.
Centistoke - 0.01 stoke (see stoke)
Centrifuge - A machine using centrifugal
force produced by high-speed rotation for separating materials
of different densities. Applied to Diesel engine fuels and lubricating
oils to remove moisture and other extraneous materials.
Cetane Index - An empirical measure
of ignition quality. Defined as the percentage by volume of
cetane in a mixture of cetane and methyl naphthalene which has
the same ignition quality when used in an engine as a fuel under
CCR - Conradson carbon residue
CFR Diesel fuel testing unit -
A standard engine employed in making cetane number tests of
Diesel engine fuels.
C/H Rati - Carbon/Hydrogen ratio
(CFB) Boilers - Used with a variety of fuels, particularly
successful at burning those of poor quality. When the flow of
air reaches a certain velocity, it causes the solid particles
to lift (or fluidize) and combustion occurs in this fluidized
Clarifie - A machine used for a
liquid-sludge separation in which the particles with a higher
specific gravity are separated form the lower specific gravity
of the liquid. A clarifier bowl has one outlet for the light
phase oil; the heavier phase particles are retained on the bowl
Cloud Point - Temperature at which
wax begins to crystallize from a distillate fuel.
The use of a single plant to simultaneously produce power and
heat or steam.
Coke - A high
carbon content solid residue from an oil refinery process, which
can be used as a boiler fuel to produce steam and electric power.
Coking - Processes
for thermally converting and upgrading heavy residual oil into
lighter products and by-product petroleum coke.
Corrosion - Detrimental change
in the size or characteristics of material under conditions
of exposure or use. It usually results from chemical action
either regularly and slowly, as in rusting (oxidation), or rapidly,
as in metal pickling.
Cracked - Refers to a petroleum
product produced by a secondary refining process such as thermal
cracking or vis-breaking processes which yield very low quality
Cracking - The
production of lighter oils by breaking down heavy oil molecules.
This process increases the yield of gasoline form crude oil.
cSt - Centistokes @ 50 Centigrade
Cutter stock - Flux Stock. A petroleum
stock which is used to reduce the viscosity of a heavier residual
stock by dilution.
- Process of removing asphaltic materials from reduced crude
using liquid propane to dissolve nonasphaltic compounds.
- A coking process that raises the temperature of the heavy
oil residue to nearly 1000° and leaves the oil in a large drum
to gradually crack the large molecules into light oil components
- The resistance of an oil to emulsification, or the ability
of an oil to separate from any water with which it is mixed.
The better the demulsibility rating, the more quickly the oil
separates from water.
Density - Density
is the term meaning the mass of a unit of volume. Its numerical
expression varies with the units selected.
Desalter - The
desalter mixes the hydrocarbon stream with a small amount of
fresh water (e.g. 10% by volume) forming a water-in-oil emulsion.
The resulting emulsion is subjected to an electric field wherein
the water is coalesced as an under flow from the upper flow
of a relatively water-free, continuous hydrocarbon phase. The
desalted hydrocarbon stream is produced at relatively low cost
and has a very small residual salt content. The performance
of this unit can be improved with a demulsifier, such as Alken
Detonation - A
violent explosion involving high-velocity pressure waves; in
a gasoline engine, the spontaneous combustion ofpart of the
compresses charge after spark occurs. Detonation usually produces
a characteristic metallic sound, or knock.
Dewaxing - Removal
of wax from petroleum products by solvent absorption, chilling
and filtering. Diesel index - Product
of the API gravity and the aniline point (in degrees Fahrenheit)
of a Diesel fuel, divided by 100; anindication of the ignition
quality of the fuel.
The process of heating a liquid to its boiling point and condensing
and collecting the vapors
Doctor test -
A qualitative method of detecting undesirable sulfur compounds
in petroleum distillates, that is, of determiningwhether oil
is "sour" or "sweet".
The refining or process of crude oil into finished fuel products.
- A process that causes the decomposition of a chemical compound
by the use of electricity.
Emulsion - A liquid
mixture of two or more liquid substances not normally dissolved
in one another, one liquid held in suspension in the other.
Water-in-oil emulsions have water as the internal phase and
oil as the external, while oil-in-water have oil as the internal
phase and water as the external.
- A viscosity obtained by dividing the out-flow time in seconds
for 200 ml. of the material being tested, by the time in seconds
for 200 ml. of water at 68F (20C) to flow out of an Engler viscosimeter.
Fahrenheit: Temperature scale based on 32F
for the temperature at which water freezes and 212F for the
temperature at which water boils (180 difference). Conversion
to Farhenheit from Celsius (centigrade) temperature scale is
by the following formula: F = 9/5C + 32, where C is the temperature
in Celsius degrees.
Feedstock - Stock
from which material is taken to be fed into a processing unit.
Final Boiling Point FBP
- The highest temperature indicated on the thermometer inserted
in the flask during a standard laboratory distillation. This
is generally the temperature at which no more vapor can be driven
over into the condensing apparatus.
Fire Point - The
lowest temperature at which an oil vaporizes rapidly enough
to burn for at least 5 seconds after ignition, under standard
Flash point -
The lowest temperature at which a liquid will generate sufficient
vapor to flash (ignite) when exposed to a source of ignition.
- A standard clause which indemnifies either or both parties
to a transaction whenever events reasonably beyond the control
of either or both parties occur to prevent fulfillment of the
terms of the contract.
Fraction - A separate
identifiable part of crude oil; the product of a refining or
- Process unit that separates various fractions of petroleum
by simple distillation with the column tapped at various levels
to separate and remove fractions according to their boiling
Fuel oil - The
heavy distillates from the oil refining process; used as fuel
for power stations, marine boilers.
Fungible - Interchangeable.
Products which can be commingled for purposes of pipeline shipment.
Gasoil - Designation
for No.2 heating oils and diesel fuels. A clean distillate fuel
Heat of Combustion Gross
- Total heat evolved during complete combustion of unit weight
of a substance, usually expresses in BTU per pound.
Heat of Combustion Net
- Gross heat of combustion minus the latent heat of condensation
of any water produced.
Heat Recovery Steam Generators
(HRSG) - A boiler that recovers heat from a gas turbine
exhaust and converts it to usable steam to improve efficiency.
Heavy crude -
Crude oil with a high specific gravity and a low API gravity
due to the presence of a high proportion of heavy hydrocarbon
fractions and metallic content.
A mechanical device which is used to create a stable, uniform
dispersion of an insoluble phase (asphaltenes) within a liquid
phase (fuel oil).
HP - Horsepower
HHV - Higher heating
Hydrocracking - This exposes heavy
fuel oil to hydrogen at high pressure and temperature in the
presence of a catalyst to reduce sulfur and produce lighter
oils by cracking the heavy oil molecules.
Hydrometer - An
instrument for determining the gravity of a liquid.
IBP - Initial
Boiling Point. In a standard laboratory distillation, the temperature
on the distillation thermometer at the moment the first drop
of distillate falls from the condenser.
Independent Power Producer
- A producer of electricity that is not regulated as a utility
by state or federal authority.
Innage - Space occupied in a product
IP - British Institute
Ionization - The
process of adding electrons to, or removing electrons from,
atoms or molecules, thereby creating ions. High temperatures,
electrical discharges, and nuclear radiation can cause ionization.
- The ratio of the absolute viscosity of a liquid to its specific
gravity at the temperature at which the viscosity is measured.
Expressed in Stokes or Centistokes. Example: Viscosity, kinematic,
cS @ 100F.....5.2
Latent heat -
Heat required to change the state of a unit weight of a substance
from solid to liquid or from liquid to vapor without change
Layering - This occurs in tanks
when a high density fuel is mixed with a low density fuel.
LHV - Lower Heating
Lifting - Refers
to tankers and barges taking on cargoes of oil or refined product
at the terminal or transshipment point.
Light Crude -
Crude oil with a low specific gravity and high API gravity due
to the presence of a high proportion of light hydrocarbon fractions
and low metallic compound.
Light Ends - The
more volatile products of petroleum refining; eg. butane, propane,
Liter - A measure
of capacity in the metric system equal to 61,022 cubic inches,
0.908 US quarts dry and 1.0567 US quarts wet.
Long Ton - An
avoirdupois weight measure equalling 2,240 pounds.
Lump-Sum Turnkey Project
- Fixed price project for which all components are within a
single supplier's responsibility.
Marine Diesel Oil (MDO)
- Marine Diesel oil is a middle distillate fuel oil which can
contain traces often percent (10%) or more residual fuel oil
from transportation contamination and/or heavy fuel oil blending.
The MDO does not require heated storage.
MCR - Maximum
MDO - Marine Diesel
Metric Ton: A weight measure equal to 1,000 kilograms, 2,204.62
pounds, and 0.9842 long tons.
Mg/L - Milligrams
per liter = ppm (parts per million) - expresses a measure of
the concentration by weight of a substance per unit volume.
- Term applied to hydrocarbons in the so-called "middle
range" of refinery distillation. Examples: heating oil,
diesel fuels, and kerosene.
Micron - A unit
of length. One millionth of a meter or one thousandth of a millimeter.
One micron equals 0.00004 of an inch.
Molecule - The
smallest division of a compound that still retains or exhibits
all the properties of the substance.
- A complex mixture of relatively volatile hydrocarbons with
or without small quantities of additives, that have been blended
to form a fuel suitable for use in spark-ignition engines.
mm - Millimeter
MSDS - Material
safety data sheet - a document that provides pertinent information
and a profile of a particular hazardous substance or mixture.
An MSDS is normally developed by the manufacturer or formulator
of the hazardous substance or mixture. The MSDS is required
to be made available to employees and operators whenever there
is the likelihood of the hazardous substance or mixture being
introduced into the workplace. Some manufacturers prepare MSDS
for products that are NOT considered to be hazardous to show
that the product or substance is NOT hazardous.
Naphtha - A volatile,
colorless product of petroleum distillation. Used primarily
as paint solvent, cleaning fluid, and blendstock in gasoline
production, to produce motor gasoline by blending with straight-run
Naphthenes - One of three basic
hydrocarbon classifications found naturally in crude oil. Naphthenes
are widely used as petrochemical feedstock. Examples are: cyclopentane;
methyl-,ethyl, and propylcyclopentane.
- The number that expresses the weight in milligrams of an alkali
needed to neutralize the acidic material in one gram of oil.
The neutralization number of an oil is an indication of its
NH3N - Ammonia
NPDES permit -
National Pollutant Discharge Elimination System permit is the
regulatory agency document issued by either a federal or state
agency which is designated to control all discharges of pollutants
from point sources into U.S. waterways. NPDES permits regulate
discharges into navigable waters from all point sources of pollution,
including industries, municipal wastewater treatment plants,
sanitary landfills, large agricultural feed lots and return
Oil - Crude petroleum
and other hydrocarbons produced at the wellhead in liquid form
Olefins - Class of unsaturated
paraffin hydrocarbons recovered from petroleum. Typical examples
include: butane, ethylene and propylene.
OSHA - The Williams-Steiger Occupational
Safety and Health Act of 1970 (OSHA) is a law designed to protect
the health and safety of industrial workers and treatment plant
operators. It regulates the design, construction, operation
and maintenance of industrial plants and wastewater treatment
plants. The Act does not apply directly to municipalities, EXCEPT
in those states that have approved plans and have asserted jurisdiction
under Section 18 of the OSHA Act. Wastewater treatment plants
have come under stricter regulation in all phases of activity
as a result of OSHA standards. OSHA also refers to the federal
and state agencies which administer the OSHA regulations.
Oxidation - Combining elemental
compounds with oxygen to form a new compound. A part of the
Oxidizing agent - Any substance
such as oxygen and chlorine , that can accept electrons. When
oxygen or chlorine is added to wastewater, organic substances
are oxidized. These oxidized organic substances are more stable
and less likely to give off odors or to contain disease bacteria.
Outage - Space left in a product
container to allow for expansion during the temperature changes
it may undergo during shipment and application. Measurement
of space that is NOT occupied in a drum.
Ozonation - The application of
ozone to water, wastewater, or air, generally for the purposes
of disinfection or odor control.
Free suspended solids.
PAH - Polycyclic aromatic hydrocarbons. (occasionally
PCB - Polychlorinated biphenyls;
polychloro-biphenyls. Difficult to remediate chemical used in
old-style transformers. Concentrated PCBs used to be referred
to as "1268".
Pensky-Martens - A closed-cup test
for flash points of oil.
Peristaltic pump - A type of positive
Petrochemical - An intermediate
chemical derived from petroleum, hydrocarbon liquids or natural
gas, such as: ethylene, propylene, benzene, toluene and xylene.
Petroleum - A generic name for
hydrocarbons, including crude oil, natural gas liquids, natural
gas and their products.
The use of refining waste products such as petroleum coke, to
fuel a power plant which produces steam and/or electricity.
pH - pH is an
expression of the intensity of the basic or acidic condition
of a liquid. Mathematically, pH is the logarithm (base 10) of
the reciprocal of the hydrogen ion concentration. The pH may
range from 0 to 14, where 0 is most acidic, 14 most basic, and
7 is neutral. Natural waters usually have a pH between 6.5 and
Phenol - An organic compound that
is an alcohol derivative of benzene.
PIB - Product Information Bulletin.
General information on a product.
Pollution - The impairment (reduction)
of water quality by agriculture, domestic or industrial wastes
(including thermal and radioactive wastes) to such a degree
as to hinder any beneficial use of the water or render it offensive
to the senses of sight, taste, or smell or when sufficient amounts
of waste creates or poses a potential threat to human health
or the environment.
Polymer - A chemical formed by
the union of many monomers (a molecule of low molecular weight).
Polymers are used with other chemical coagulants to aid in binding
small suspended particles to form larger chemical flocs for
easier removal from water. All polyelectrolytes are polymers,
but not all polymers are polyelectrolytes.
Polymerization - Process of combining
two or more simple molecules of the same type, called monomers,
to form a single molecule having the same elements in the same
proportion as in the original molecules, but having increased
molecular weight. The product of the combination is a polymer.
Pour Point - Lowest temperature
at which an oil will pour or flow under certain prescribed conditions.
ppm - Parts per million - the unit
commonly used to designate the concentration of a substance
in a wastewater in terms of weight ie. one pound per million
pounds, etc. PPM is synonymous with the more commonly used term
mg/L (milligrams per liter).
Pulverized Fuel (PF)
Boilers - Usually in the higher capacity range (over
200 MW), fueled by pulverized solid coal or petroleum coke.
Traditionally, customers are utilities.
Purifier - A machine
used for a liquid-liquid separation in which the two intermixed
liquids which are insoluble in each other have different specific
gravities. Solids with specific gravities higher than those
of the liquids can be separated off at the same time. A purifier
bowl has two outlets; one for the light phase liquid and one
for the heavy phase liquid.
- A carbon residue test originated by Dr. J.R. Ramsbottom in
Reagent - A pure chemical substance
that is used to make new products or is used in chemical tests
to measure, detect, or examine other substances.
Recycle - The use of water or wastewater
within (internally) a facility before it is discharged to a
Reduced Crude Oil - Crude oil that
has undergone at least one distillation process to separate
some of the lighter hydrocarbons. Reducing crude lowers its
API gravity, but increases the handling safety by raising the
Reducing agent - Any substance,
such as the base metal (iron) or the sulfide ion that will readily
donate (give up) electrons. The opposite of an oxidizing agent.
Redwood viscosity - The number
of seconds required for 50 ml. of an oil to flow out of a standard
Redwood viscosimeter at a definite temperature; British viscosity
Refinery - A plan used to separate
the various components present in crude oil and convert them
into usable products or feedstock for other processes.
Residual Fuel Oil
- Heavy fuel oils produced from the non-volatile residue from
the fractional distillation process. Heavy oils that are "leftovers"
from various refining processes. Heavy black oils used in marine
boilers and in heating plants.
Saybolt Furol viscosity
- A viscosity test similar in nature to the Saybolt Universal
viscosity test but one more appropriate for testing high=viscosity
oils. Certain transmission and gear oils, and heavy fuel oils
are rated by this method. The results obtained are approximately
1/10th the viscosity which would be shown by the Saybolt Universal
Scrubbing - Purification
of a gas by washing it with a liquid in a tower.
SSF - Seconds
SSU - Seconds
Short ton - An
avoirdupois measure of weight equal to 2,000 lbs.
Slagging - Formation
of hard deposits on boiler tubes and/or piston crowns, usually
due to the presence of sodium, vanadium and sulfur.
Sludge - Deposits
in fuel tanks and caused by the presence of wax, sand, scale,
asphaltenes, tars, water, etc. The "sludge" formed
in a #6 fuel oil storage tank is mostly composed of heavy hydrocarbons.
Alken Even-Flo® 905 eliminates this type of sludge by breaking
the sludge into small particles and re-suspending them in the
fuel for more efficient combustion. The "sludge" formed
in diesel storage tanks is a combination of water with fungus
and bacteria, which grow on the unevenly mixed water/fuel interface.
Adding Alken Even-Flo® 910 and 910S to stored fuel promotes
a clean separation of water and fuel, reducing the substrate
upon which bacteria and fungus can grow. Since the bacteria
and fungus bind to the separated water, they can be removed
by draining the water from the storage tank. If draining the
storage tank is impossible, EF 905 and 910E will emulsify the
water into tiny droplets and break the sludge into such small
particles that they will no longer clog filters and will efficiently
Soluble - Matter
or compounds capable of dissolving into a solution.
Solvent: A substance, normally a liquid, which is capable of
absorbing another liquid, gas, or solid to form a homogeneous
- Extracts higher quality oils using a solvent, leaving pitch
or asphalt residue (see Deasphalting).
- Term referring to the properties of a given crude oil or petroleum
product, which are "specified" since they often vary
widely even within the same grade of product. In the normal
process of negotiation, seller will guarantee buyer that product
or crude to be sold will meet certain specified limits, and
will agree to have such limits certified in writing. Generally
the major qualities of oil for which a buyer would demand a
guarantee are: API gravity (or specific gravity, in some cases),
sulfur percentage measured by weight, pour point measured by
degrees C maximum, viscosity min./max., BS&W percentage
by weight, etc.
Specific gravity - Weight of a
particle, substance or chemical solution in relation to an equal
volume of water at 15C. Abbreviated as Sp.Gr.
- The quantity of heat required to raise the temperature of
a unit weight of a substance by 1 degree; usually expresses
as calories/gram/C or BTU/lb./F.
Spec. Sheet -
Specification Sheet. Detailed information of a product including,
tests, color, odor, specific gravity, bacterial strains, other
major ingredients, etc.
SIT - Spontaneous
Ignition Temperature. The temperature at which an oil ignites
of its own accord in the presence of air or oxygen under standard
SR1 - Seconds
Redwood # 1 @ 100 F
Stabilize - To
convert to a form that resists change. Organic material is stabilized
by bacteria which convert the material to gases and other relatively
inert substances. Stabilized organic material generally will
not give off obnoxious odors.
Static mixer -
A motionless mixer which has a series of fixed, geometric elements
enclosed within a tubular housing. The internal elements impart
flow division and radial mixing to the media flowing through
the housing to produce a uniform dilution of the production.
Stoke - The unit
of kinematic viscosity
Refers to a petroleum product produced by the primary distillation
of crude oil, free of cracked components.
- Occurs in blended fuels that have a compatibility problem.
It is usually experienced when paraffinic based oils are mixed
with asphaltic based oils, causing asphaltenes to precipitate
and settle to the bottom of the tank.
STP - Standard
Temperature (25C) and Pressure (300 mm Mercury).
Sulfur - An element
that is present in crude oil and natural gas as an impurity
in the form of its various compounds.
Surfactant - Surface-active
agent. The active agent in detergents that possesses a high
cleaning ability. Used in a spray solution to improve its sticking
and wetting properties when applied to plants, algae, or petroleum.
- An instrument used to determine the color of oils. Also a
scale of color values.
TBN - Total Base Number. ASTM D2896.
This is measured in mg. KOH needed to neutralize an acidic solution
through a reverse titration. TBN is the ability of the product
to neutralize acid. In a motor oil, this is a property which
allows the oil to neutralize acids from combustion that would
otherwise degrade the oil.
- The breaking up of heavy oil molecules into lighter fractions
by the use of high temperature without the aid of a catalyst.
Thermal Value - Calories per gram
of BTU per pound produced by burning fuels.
Topped Crude Oil - Oil from which
the light ends have been removed by a simple refining process.
Also referred to as "reduced crude oil".
Total Existent Sediment - Combination
of inorganic and hydrocarbon sediments existing in a fuel as
Toxic - A substance which is poisonous
to a living organism.
Toxicity - The relative degree
of being poisonous or toxic. A condition which may exist in
wastes and will inhibit or destroy the growth or function of
- A project in which all components are within a single supplier's
responsibility (see Lump-Sum Turnkey Project).
- A suspended level apparatus for accurately determining the
viscosity of a liquid.
Ullage - The amount
which a tank or vessel lacks of being full.
Upstream - The
exploration, production, and transportation of oil and gas.
- An organic and/or inorganic metal bearing chemical intended
to chemically and/or physically combine with the compounds formed
during combustion of heavy fuel oil to improve the surface properties
of the treated ash compounds.
A device for determining the viscosity of oil. There are several
methods or devices in general use. Basically, a fixed quantity
of oil is allowed to pass through a fixed orifice at a specified
temperature over a measured time span and then compared to a
standard liquid such as a calibration oil or water.
Viscosity - Measure
of the internal friction or resistance of an oil to flow. As
the temperature of an oil is increased, its viscosity decreases
and it is therefore able to flow more readily. Viscosity is
measured on several different scales, including Redwood No.
1 at 100F, Engler Degrees, Saybolt Seconds, etc. The most common
method for designation of viscosity is kinematic viscosity,
measured in centistokes, cst @ 50Centigrade. (See Saybolt Furol,
Saybolt Universal, Engler, Redwood, Kinematic)
Vis-Breaking or Visbreaking
- A light thermal cracking process carried out on a fuel
oil during the refining process to reduce product viscosity
without blending. It Heats the heavy oil residue to a high temperature
to crack some of it to lighter components and reduce the quality
of heavy residue remaining.
Volatile - A volatile
substance is one that is capable of being evaporated or changed
to a vapor at a relatively low temperature. Volatile substances
also can be partially removed by air stripping.