Important Terms and their Meaning of Mechanical Engineering- Fuels and Combustion:
ACCELERATOR – Device for rapid control of the speed of an engine, for quick opening and closing of the throttle which regulates the quantity of air fuel mixture into the engine cylinder.
ACHESON
GRAPHITE – That made from coke in an electric furnace.
ACTIVATED
CARBON – A highly absorbent form of carbon used to remove odours and toxic
substances from gaseous emissions or to remove dissolved organic matter from
waste water.
ADDITIVE –
A substance added to fuel or oil or grease which improves the properties of the
same.
ADIABATIC
FLAME TEMPERATURE – The maximum possible temperature attained by the
products of reaction, when the reaction goes to completion and all the heat
released is used to heat up the products.
AERATION
TEST BURNER – Apparatus by which the combustion characteristics of
commercial gases can be correlated and calibrated.
AEROSOL –
A particle of solid or liquid matter that can remain suspended in the air
because of its small size. Particulates under 1 micron in diameter are called
aerosols.
AFTER
BOIL – Boiling of the fuel in the carburettor or coolant in the engine
immediately after the engine is stopped.
AFTER
BURNING – In an internal combustion engine, the persistence of the
combustion process beyond the period proper to the working cycle, i.e.,
into the expansion period.
AFTER
BURNER – In an automobile engine, a type of exhaust manifold that burns the
hydrocarbon and carbon monoxide remaining in the exhaust gas.
AIR
ASPIRATOR SYSTEM – An air injection system using a valve opened and closed
by pulses in the exhaust system.
AIR FUEL
MIXTURE – Air and fuel travelling to the combustion chamber after being
mixed by the carburettor.
AIR FUEL
RATIO – Ratio (by weight) between air and fuel that makes up engine fuel
mixture.
AIR
INJECTION SYSTEM – A system which injects air into the exhaust manifold or
thermal reactor so that the combustion of the carbon monoxide and unburned
hydrocarbons in the exhaust can be completed.
AIR MASS
METERING – In some fuel injection systems, fuel metering is controlled
primarily by engine speed and the amount of air actually entering the engine.
AIR
POLLUTION – Contamination of earth’s atmosphere by various natural and manmade
pollutants such as smoke, gases, dust etc.
ALCOHOL –
Volatile liquid fuel consisting wholly or partly, of alcohol, able to withstand
high compression ratios without detonation.
ANTHRACITE
COALS – Slow burning coals which yield very little ash, moisture and less
than 10 per cent volatiles, generally used in closed stoves.
ANILINE
POINT – The lowest temperature at which an oil is completely miscible with
an equal volume of aniline.
ANTIBACKFIRE
VALVE – Valve used in air injection reaction exhaust emission control
system to prevent backfiring during the period immediately following sudden declaration.
ANTIKNOCK
– In engine fuels, that property which opposes knocking i.e., auto
ignition.
ANTIKNOCK
COMPOUND – An additive put into gasoline to suppress knocking or detonation
e.g., Tetra ethyl lead.
ANTIPERCOLATOR
– Device for venting vapours from main discharge
tube, or
well, of a carburettor.
APIEZON
OILS – The residue of almost zero vapour pressure left by vacuum
distillation
of petroleum products.
API
GRAVITY – The American Petroleum Institute (API) has established
the formula
for calculating the specific gravity of a fuel or oil as Degree
API=
((141.5/specific gravity at 60/60 degree F)–131.5). The symbol
60/60 degree
F is interpreted as the ratio of the weight of a given volume
of oil at 60
degree F to the weight of the same volume of water at 60
degree F.
ASH –
An inorganic non-combustible residue obtained by combustion of
an oil or
fuel in the presence of air.
ASH AND
SLAG – Impurities that do not burn and usually troublesome
elements in
coal fired boilers.
ASH FREE
BASIS – When fuels are delivered on an ash free basis, it means
that the
percentage of the ash has been deducted and the other
constituents
have their percentages recalculated on 100 per cent total
without the
ash.
ATMOSPHERIC
GAS BURNER SYSTEM – A natural draught burner
injector, in
which the momentum of a gas stream projected from an
orifice into
the injector throat inspirates from the atmosphere a part of
the air
required for combustion.
ATOMIZATION
– The spraying of a liquid through a nozzle so that the
liquid is
broken into a very fine mist.
ATOMIZER –
A nozzle through which oil fuel is sprayed into the combustion
chamber of
an oil engine or boiler furnace. It breaks up the fuel into a
fine mist so
as to ensure good dispersion and combustion.
A
UTOIGNITION
– The self-ignition or spontaneous combustion of a fuel
when
introduced into the heated charge in the cylinder of a compression
ignition
engine.
AUTOMATIC
CHOKE – A carburettor choke device (valve) that
automatically
positions itself in accordance with the carburettor needs
or engine
temperature.
BACKFIRE
(exhaust system) – Passage of unburned air fuel mixture into
the exhaust
system where it is ignited by some hot spot and causes a
loud
explosion.
BALANCED
DRAFT – A boiler using both forced draft fan and induced
draft fan,
can be regulated and balanced in the amount of air and flue
gases
handled so that the furnace pressure is almost atmospheric.
BAGASSE –
A fuel produced as a by product of the abstraction of juice
from sugar
cane. The dried cane (fibrous residue) is usually fed into a
specially
designed furnance by means of overfeed stokers.
BENCH –
The name applied to a complete plant for the manufacture of
coal gas.
Also called RETORT BENCH.
BENZOL –
Crude benzene, used as a motor spirit, generally mixed with
petrol, and
valued for its antiknock properties.
BIOGAS –
Obtained by fermentation in the sewage disposal system, or by fermentation of
cattle waste, farm waste etc.
BIOSPHERE
– The portion of earth and its atmosphere that can support life.
BLAST
FURNANCE GAS – A gas of low calorific value, a by product of iron smelting
due to burning of coke in the furnace with limited air, used for preheating the
blast, for steam raising etc. It may contain up to 30% carbon monoxide.
BLAST
MAIN – The main blast air pipe supplying air to a furnace.
BLOW BY –
Leakage of unburned air fuel mixture and some burned gases past the piston
rings into the crankcase during the compression and
combustion
strokes.
BLOW
TORCH EFFECT – In gas or oil burning furnaces, when the flame impinges on
any surface, such as a tube or refractory wall, that surface is burned as by a
blow torch. This is a combustion condition to be avoided as destructive to the
surface.
BLUE
WATER GAS – A mixture of approximately equal proportions of carbon monoxide
and hydrogen made by passing steam over incandescent coke in special
generators.
BOILING
POINT – The temperature at which a liquid begins to boil.
BOMB
CALORIEMETER – An apparatus used for determining the calorific values of
fuels. The bomb consists of a thick walled steel vessel in which a weighed
quantity of fuel is ignited in an atmosphere of compressed oxygen. The bomb is
immersed in a known volume of water; from the rise of temperature of water the
calorific value is calculated.
BOTTLED
GAS – LPG (liquefied petroleum gas) compressed into strong metal
containers. Gas when confined in tank, under pressure, is in the liquid form.
BRIQUETS –
Coherent masses of uniform size made by the application of pressure to any
powdery material placed in a suitable mould with or without a binder.
BUTANE –
A hydrocarbon gas formed synthetically, by the action of zinc or ethyl iodide.
Petroleum gas, that is liquid, when under pressure. Often used as engine fuel
in trucks.
CALORIE –
The amount of heat required to raise one gram of water through 1°C i.e.,
from 17 to 18°C. Calorie is unit of heat.
CALORIFIC
INTENSITY – The maximum flame temperature attained when the fuel is burnt.
CALORIFIC
VALVE – The heat value of a fuel, expressed in either BTU per pound or CHU
per pound or kilocalories/kg. The amount of heat produced by burning unit
weight of fuel.
CALORIEMETER
– Measuring instrument used to determine the amount of heat produced when a
substance is burned, also friction and chemical change produce heat.
CARBON –
One of the non-metallic elements constituting fuel and lubricating oil.
CARBON
DEPOSIT – A black, hard or soft deposit left on engine parts by the
combustion of fuel. Carbon forms on pistons, rings, plugs, valve heads etc.,
inhibiting their action.
CARBONDIOXIDE
– A colourless, odourless gas which results when hydrocarbon or carbon is
burned completely.
CARBONIZE
– Building up of carbon on objects such as spark plug, piston head etc., of
an engine.
CARBON
MONOXIDE – A colourless, odourless, tasteless, poisonous gas found in
engine exhaust. Formed when carbon or hydrocarbons are burned incompletely.
CARBURETED
WATER GAS – An artificial gas formed by passing steam through a bed of
glowing coke and thereafter enriching the gas so formed with petroleum vapour.
CATALYTIC
CONVERTER – A muffler like device for use in an exhaust system that
converts harmful gases in the exhaust into harmless gases by promoting a
chemical reaction between a catalyst and the pollutants.
CETANE
NUMBER – Rating of ignition quality or performance characteristic of diesel
fuel. A high cetane number fuel ignites more easily at lower temperature than a
low cetane number fuel.
CHARCOAL –
Product obtained by heating wood out of contact with air.
CHARCOAL
CANISTER – A container filled with activated charcoal used to trap gasoline
vapour from the fuel tank and carburettor while the engine is off.
CHEMICAL
CHANGE – A change which alters the composition of the molecules of a
substance producing new substances with new properties.
CLOUD
POINT – The temperature of a liquid (fuel or lubricant) at which a haze or
a cloud first appears in a sample of oil, when cooled in a prescribed manner.
COAL –
A firm, brittle, sedimentary, combustible rock derived from vegetable debris
which has undergone a complex series of chemical and physical changes during
the course of many million years.
COAL GAS –
A fuel formed by the distillation of coal, usually in a retort or a coke oven.
COEFFICIENT
OF HAZE – A measurement of visibility interference in the atmosphere.
COKE –
A fused cellular porous structure that remains after the free moisture and the
major portion of the volatile matter have been distilled from coal.
CAKING
COALS – Coals that become soft under the usual furnace temperatures and
merge into undesirable masses of coke. The coal that becomes soft, melts and
solidifies into a more or less solid mass which further hardens on heating out
of contact with air.
COLLOIDAL
FUEL – A mixture of fuel oil and powdered coal.
COMBUSTION
– Process involved during quick burning. Release of chemical energy into
heat energy occurs during combustion.
COMBUSTION
EFFICIENCY – is the ratio of the (heat) energy liberated to that which
could be liberated under ideal conditions. Quantity of CO2 and H2O in the
exhaust indicate energy liberated, whereas the quantity of H2, CO
and CH₄ indicate unliberated energy.
CRACKING –
The process of breaking of heavy molecules into lighter hydrocarbons.
COMPRESSION
IGNITION – Ignition of fuel through the heat of compression as in a diesel
engine.
COMPRESSED
NATURAL GAS – usually assumes the form of compressed methane, and is
suitable for obtaining ultra low emissions from combustion engines. Soot
production is virtually zero.
COMPOUND –
A combination of two or more ingredients mixed together.
CONSTANT
PRESSURE COMBUSTION – Combustion which occurs without a change in pressure.
In an engine, this is obtained by the slower rate of burning than with constant
volume combustion.
CRUDE OIL
– Petroleum as it comes from the oil well (raw or refined state). It forms
the basis of gasoline, engine oil, diesel oil, kerosene etc.
DETONATION
– An uncontrolled instantaneous second explosion in a spark ignition
engine, after the spark occurs, with excessively rapid burning of a portion of
the compressed air fuel mixture (end charge almost exploding) resulting in a
spark knock, or pinging noise.
DIESEL
INDEX – A rating of fuel according to its ignition qualities. The higher
the diesel index number, the better the ignition quality of the fuel.
DIMETHYLETHER
– is a synthetic product with a high cetane number, producing little soot
and reduced nitrogen oxide when combusted in diesel engines.
DISTILLATION
– Heating a liquid, and then catching and condensing the vapours given off
by the heating process.
DRAFT –
The differential pressure in a furnace to ensure the flow of gases out of the
furnace and flow of air into the furnace.
DUST –
Fine grain particles light enough to be suspended in air.
ECOSPHERE
– The layer of earth and troposphere inhabited by or suitable for existence
of living organisms.
EFFLUENT –
Waste material discharged into the environment, treated or untreated.
EGR
SYSTEM – Exhaust gas recirculation system. It sends part of the exhaust gas
back through the engine by way of the carburettor or intake manifold, which
reduces the amount of NOx that is formed by an engine.
ELECTOSTATIC
PRECIPITATOR – An air pollution control device in which solid or liquid
particulates in a gas stream are charged as they pass through an electric field
and precipitated on a collection surface.
ELUTRIATION
– A process of separating lighter particles from heavier particles by
washing solid waste with a slowly moving upward stream of fluid that carried
the lighter particles with it.
EMISSION
CONTROLS – A term applied to any device or modification added onto, or
designed into a motor vehicle for the purpose of controlling a source of air
pollution emission.
ETHANOL –
Ethyl alcohol produced by east fermentation of a variety of carbohydrates such
as saccharin (sugar canes, sugar beets, molasses and fruit juices), starch
(cereals and potatoes) or cellulose (wood waste, sulphite liquor).
ETHYL
GASOLINE – Gasoline to which ethyl fluid has been added to improve its
resistance to knocking. Slows down burning rate and thereby creates a smooth
pressure curve that will allow the gasoline to be used in high compression
engines.
EVAPORATIVE
EMISSION CONTROL SYSTEM – A system which prevents the escape of gasoline
vapours from the fuel tank or carburettor float bowl to the atmosphere while
the engine is off.
The vapours
are stored in a canister, or in the crankcase until the engine is started.
EXCESS
AIR – Air present in the cylinder over and above that which is theoretically
necessary to burn the fuel.
EXHAUST
GAS – The products of combustion coming out from an internal combustion
engine.
EXHAUST
GAS ANALYZER – A device for sampling the exhaust gas from an engine to
determine the amounts of pollutants in the exhaust gas. This determines
combustion efficiency.
FLAME
DETECTOR – A device that monitors the flame in a furnace that is burning
oil, gas, or pulverized coal fuel. Failure of the flame results in a signal and
the actuation of various protective controls on the fuel feed to prevent an
explosion.
FLAME
SAFEGUARD SYSTEM – An arrangement of flame detection system, interlocks and
relays, which will sense the presence of a proper flame in a furnace and cause
fuel to be shut off to the furnace if a hazardous (improper flame or
combustion) condition develops.
FLASH
POINT – It is the temperature at which the quantities of vapour which a
combustible fuel emits into the atmosphere are sufficient to allow a spark to
ignite the vapour air mixture above the fluid.
FLUE DUST
– Solid particles (smaller than 100 microns) carried in the products of
combustion.
FLUE GAS
ANALYZER – Device which measures the percentages of volume of
carbondioxide, carbon monoxide and oxygen in the flue gas of a boiler.
FLY ASH –
Combustion ash so fine that is carried up and into the atmosphere by the
movement of the flue gases. It can become neighbourhood nuisance by settling on
surfaces in the area after it loses its velocity.
FOG –
Suspended liquid particles formed by condensation of vapour.
FORCED
DRAFT FAN – The fan that pushes or forces air into the furnace, usually at
a pressure higher than atmospheric pressure.
FRACTIONAL
DISTILLATION – A process of separation on the molecular basis or on the
basis of the boiling point of various fractions.
FREE
LIQUIDS – Liquids which readily separate from the solid portion of a waste
under ambient temperature and pressure.
FUEL –
The substance that is burned to produce heat and create motion in an engine or
heat substances. Any combustible substance.
FUEL
CALORIEMETER – A meter (also called oxygen bomb) to determine the heating
value of 1 kg of fuel by burning a sample of the fuel under controlled
conditions.
FUGITIVE
DUST – Particulate matter composed of soil which is uncontaminated by
pollutants resulting from industrial activity. Fugitive dust may include
emissions from haul roads, wind erosion of exposed soil surfaces and soil
storage piles, and other activities in which soil is either removed, stored,
transported, and redistributed, also solid air borne particulate matter emitted
from any source other than through a stack.
FUME –
Any kind of noxious vapour arising from a process of combustion or chemical
reactions. Includes smoke, odorous materials, metallic dust.
FUME
AFTERBURNERS – Units designed to consume combustible fumes by means of a
direct fired combustion chamber through which the fumes must pass on their way
to the stack and the atmosphere.
FURNACE
EXPLOSION – The ignition and almost instantaneous explosion of highly
inflammable gas, vapour or dust accumulated in a boiler setting.
GAS –
A state of matter, neither solid nor liquid which has neither definite shape
nor definite volume. Air is a mixture of several gases.
GASOLINE –
A liquid blend of hydrocarbons, obtained from petroleum crude oil, used as the
fuel for most automobile SI engines.
GRINDABILITY
– A descriptive term of a characteristic of coal that is important to
pulverized coal systems.
HEATING
VALUE OF A FUEL – The heat liberated by the complete and rapid burning of a
fuel per unit weight or volume of the fuel. Also called calorific value of the
fuel.
HIGHER
HEAT VALUE – A standard recommended by the ASME, the higher heat value of a
fuel includes the heat value of the hydrogen in the fuel. The heating value
indicated by a fuel calorimeter.
HIGH TEST
GASOLINE – A term referring to the octane rating of a fuel. A high test
fuel has a high octane rating.
HOGGED
FUEL – Wood that has been chipped and shredded, usually by a machine called
a “hog”.
HYDROCARBON
– A compound made of elements of hydrogen and carbon atoms. Gasoline, diesel
oil are blends of different hydrocarbons refined from crude oil.
IGNITION
TEMPERATURE – The temperature at which the heat that is generated by the
reaction between air and fuel vapour, is faster than that is lost to the
surroundings, and combustion thus becomes self propelling. Below this point,
the gas air mixture will not burn freely.
IGNITION
QUALITY OF DIESELS – is indicated by cetane number. It is the percentage of
cetane by volume, in a mixture of cetane (C16 H34) and alpha methyl naphthalene
which will exhibit the same ignition characteristic of the fuel under test when
tested in a standard engine, under a set of standard test conditions.
INCINERATION
– The controlled process in which the combustible solid, liquid or gaseous
wastes are burned and changed into non-combustible gases.
INCINERATOR
– Any furnace used in the process of burning waste for the primary purpose
of reducing the volume of the waste by removing combustible matter.
INDUCED
DRAFT FAN – The fan that draws the gases out of the furnace by creating a
partial vacuum on the suction side of the fan.
INFRARED
GAS ANALYZER – A non-dispersive infrared gas analyzer used to measure very
small quantities of the pollutants contained in the exhaust gas.
KEROSENE –
This petroleum product is a liquid fuel having an average latent heat of vaporization
of 105-110 BTU lb and the specific heat of 0.50, sometimes called COAL OIL.
KNOCK
(engine) – In an engine, a rapping or hammering noise resulting from
excessively rapid burning of the compressed air fuel charge.
LIGNITE –
A coal of high moisture content and low calorific value, generally less than
8300 BTU/lb. May require predrying before being used as a fuel.
LIQUID
ASH REMOVAL SYSTEM – An arrangement of piping by which molten ash is removed
continuously or intermittently, as desired, from the bottom of a furnace. The
operating medium is usually compressed air with pneumatic controls.
LIQUEFIED
PETROLEUM GAS (LPG) – A gas fuel that is stored in liquid form and is
converted into gas as it leaves the storage tank by a pressure regulator that
steps down the storage pressure on the liquid at the tank outlet and thereby
permits the liquid to assume its normal gaseous state at the existing
temperature and reduced pressure.
LONG
FLAME BURNER – An oil or gas burner in which the mixture of fuel and air is
delayed long enough to produce a long flame from the burner nozzle. Can be a
source of trouble if the flame impinges on either refractory or tube surfaces.
LOWER
HEATING VALUE – Net heat liberated per kg of fuel after the heat necessary
to vaporize and superheat the steam formed from the hydrogen (and from the
fuel) has been liberated.
LOW LEAD
FUEL – Gasoline which is low in tetraethyl lead (approximately 0.5 gm per
gallon).
MECHANICAL
DRAFT – Draft produced artificially by means of forced or induced draft
fans.
METHANOL –
Methyl alcohol produced from coal by its liquifaction, by pyrolysis, or by its
reaction with high pressure hydrogen.
NATURAL
DRAFT – Draft produced by a chimney, by a column of hot gases existing
inside the chimney.
NATURAL
GAS – Gas obtained from petroleum mines.
NOx –
Oxides of nitrogen, a by-product of combustion within the combustion chamber at
high temperature and under heavy load. A basic air pollutant.
NOx CONTROL
– Any type of device, or system, used to reduce the amount of NOx produced
by an engine.
NO LEAD
FUEL – Gasoline to which there has been no intentional addition of lead
compounds.
OCTANE
RATING – The measure of antiknock property of gasoline. The higher the
octane rating, (OCTANE NUMBER), the more resistant the gasoline is to knocking
or detonation and better the quality: Higher compression engines require higher
octane gas.
OCTANE
NUMBER OF A FUEL – is the percentage by volume of isooctane in a mixture of
iso-octane (C8 H18) and n-heptane (C7 H16)
which will exhibit the same antiknock characteristic of the fuel under test
when tested in a standard CFR variable compression ratio engine, under a set of
standard test conditions.
OIL
BURNER – Any device wherein oil fuel is vaporized or so called atomized and
mixed with air in proper proportion for combustion.
PARTICULATES
– Small particles of lead and other substances occurring as solid matter in
the exhaust gas.
PEAT –
A substance of vegetable origin always found more or less saturated with water
in swamps and bogs.
PETROLEUM
– Crude oil as it comes out of the ground, which consists of 83-87 percent
carbon, and 10-14 percent hydrogen, plus traces of oxygen, nitrogen and
sulphur. From the crude oil, gasoline, diesel, lubricating oil and other
products are refined.
PHOTOCHEMICAL
SMOG – The result of sunlight reacting with hydrocarbons and nitrogen
oxides in the atmosphere.
PING –
The sound resulting from sudden auto ignition of the air-fuel charge in a SI
engine combustion chamber. Characteristic sound of detonation.
POLLUTANTS
– Any gas or substance in the exhaust gases from the engine or that
evaporates from the fuel tank or carburettor. These gases or substances add to
the pollution of our atmosphere.
POLLUTION
– The presence of matter or energy whose nature, location or quantity
produces undesirable environmental effects.
POSITIVE
CRANKCASE VENTILATION – PCV system-A crankcase ventilating system which
produces the circulation of air through the crankcase, thus clearing it of
water vapour, unburned hydrocarbons, and blow by, the air passes into the
intake system of the engine and hence into the combustion chambers where they
are burnt.
POT TYPE
BURNER – It is a hot plate burner in which the fuel oil drops into a hot
plate and vaporizes.
POUR
POINT OF FUEL – is the temperature at which crystals begin to appear and
the fuel flow will be interrupted, as the fuel is being cooled.
PREI-GNITION
– Ignition of air fuel mixture in the SI engine cylinder (by any means)
before the (ignition) spark occurs at the spark plug terminals.
PRIMARY
AIR – The air mixed with the fuel at or in the burner. It ensures instant
combustion as the fuel enters the furnace.
PRIMARY
POLLUTANT – A pollutant emitted directly from a polluting source.
PROPANE –
A type of LPG that is liquid below –42°C at atmospheric pressure.
PULSATION
– A panting of the flames in a furnace, indicating cyclic and rapid changes
in the pressure in the furnace.
PURGE –
The evacuation of air or any other designated gas from the duct line, pipe
line, container or furnace. Purging may be done in some instances simply by the
use of a fan or blower, in others by driving out the air or gas by means of an
inert gas, such as nitrogen, under high pressure.
RADIOACTIVE
– Substances that emit rays either naturally or as a result of scientific
manipulation.
REFUSE –
A term generally used for all solid waste materials.
RETORT –
A trough or channel built into an underfeed stoker through which the stoker ram
pushes green coal into the fire. The coal enters the fire from below, hence the
name “underfeed”.
ROTARY
BURNER – One in which the oil entering at the center of a rotary cup is
whirled around very rapidly until the oil is thrown away from the cup. By centrifugal
force it mixes with air and ignites.
SAFETY
CONTROLS – Devices that guard against (1) overpressure leading to
explosions from the water side or steam side, (2) overheating of metal parts,
possibly also leading to explosion in a fired boiler, (3) fire side explosions
(furnace explosions) due to uncontrolled combustible mixtures on the firing
side.
SECONDARY
AIR – Air introduced into a furnace above and around the flames as may be
necessary to promote combustion. This air is in addition to the primary air
which enters either as a mixture with fuel or as blast underneath a stoker.
SHREDDER–
A machine used to break up waste materials into smaller pieces by cutting or
tearing.
SCRUBBER –
A device that uses a liquid spray to remove aerosol and gaseous pollutants from
an air stream.
SLACK –
A coal of fine size, often screenings, and maximum size is not likely to exceed
62.5 mm.
SLAG TAP
FURNACE – A furnace for burning pulverized fuel in which the ash puddles in
the bottom of the furnace in a molten state and is removed periodically or
continuously, depending on the design of the system, while still in the molten
condition.
SMOG –
A term coined from smoke and fog. This is applied to the fog like layer that
hangs over many areas under certain atmospheric conditions. Smog is compounded
from smoke, moisture and numerous chemicals which are produced by combustion
and from numerous natural and industrial processes.
SPECIFIC
GRAVITY – A measure of the weight per unit volume of a liquid as compared
with the weight of an equal volume of water.
SURFACE
IGNITION – Ignition of air fuel mixture in the combustion chamber produced
by hot metal surfaces or heated particles of carbon.
SYNTHETIC
FUELS – Fuels such as ethanol and butanol derived from coal, and hydrogen
from water.
TETRA
ETHYL LEAD – A chemical put into engine fuel which increases octane rating,
or reduces knock tendency. Also called ethyl and tel.
TORCH –
Combustible material on a metal rod, such as oil soaked rags, used to light up
oil and gas burners. The torch is extinguished by being plunged into a prepared
receptacle.
TUYERES –
Castings appearing as components of underfeed stokers and designed to admit air
to the green coal moving through the retorts.
VAPOURIZATION
– To change a liquid into a vapour, often by the addition of heat.
VAPOURIZING
BURNER – A burner in which the fuel oil is vaporized by heating in a
retort. It may be a mixing or non mixing type.
VAPOUR
LOCK – A condition in the fuel system in which gasoline has vaporized and
turned to bubbles in the fuel line or fuel pump, so that the fuel delivery to
the carburettor of a SI engine is prevented or retarded.
VOLATILITY
– refers to the ease with which a liquid vaporizes. A liquid which vaporizes
at a relatively low temperature has a high volatility. This liquid is said to
be highly volatile.
WIND BOX –
A plenum from which air is supplied to a stoker or to gas or oil burners.