|
A
|
|
|
ABMA
|
American
Boiler Manufactures Association.
|
|
ABSORPTION
SYSTEM
|
Refrigeration
system that uses lithium bromide as the
refrigerant and steam as the means to
pressurize the refrigerant.
|
|
ACID
|
The hydrogen form
of an ion.
|
|
ACID
CLEANING
|
Procedure for
removal of waterside deposits in which an acid
based material is used as the primary cleaning
agent.
|
|
ADSORPTION
|
Physical adhesion
of molecules or colloids to the surface of
solids without chemical reaction.
|
|
AERATION
|
Process of
introducing air into water.
|
|
AEROBIC
ORGANISM
|
An organism that
requires oxygen for its respiration.
|
|
AIRBORNE
CONTAMINANT
|
Solids
or gases brought into an open cooling system
water in the air flowing through the tower.
|
|
ALGAE
|
Simple
plants. Under conditions favorable for
their growth, they mature into colonies and
produce mats of similar masses.
|
|
ALKALINITY
|
Bicarbonate,
carbonate or hydrate amounts in
water. Usually expressed as "M"
alkalinity to a methyl orange titration end
point or "P" alkalinity to a phenolphthalein
end point.
|
|
AMBIENT
TEMPERATURE
|
1. Outdoor
temperature as reported by periodic
readings. 2. Also known as the dry
bulb temperature, measured in the regular
manner with conventional
instruments.
|
|
AMINE
|
A class of
chemical inhibitor used to control rate of
corrosion in condensate return piping and
related components. See FILMING
AMINE, MORPHOLINE,
NEUTRALIZING
AMINE AND SOY
AMINE.
|
|
AMORPHOUS
|
With a definite
crystalline structure. Atoms or
molecules not arranged in a definite pattern.
|
|
AMPHOTERIC
|
A metal oxide
that will dissolve in both an acid or alkaline
environment, i.e., aluminum, zincs.
|
|
ANALYSIS
|
Separation and
measurement of component parts.
|
|
ANAEROBE
|
Type of
microorganism which can exist without air or
free oxygen.
|
|
ANION
|
Ion which carries
a negative charge.
|
|
ANODE
|
Region of lower
potential in a corrosion cell. Area of
corrosion where metal is removed.
|
|
ANODIC
INHIBITOR
|
Corrosion
inhibitor that forms a thin protective film
over anode in a corrosion cell.
|
|
ANTIFOAM
|
Class of chemical
treatment used in water to limit foaming of
system water.
|
|
ANTIPRECIPITANT
|
Chemical
that retards the precipitation of insoluble
salts, usually by interposing itself in the
crystal structure.
|
|
ANTISCALANT
|
Chemical that
reacts with impurities to change chemical
structure or which alters the action of the
impurities.
|
|
ANTISEPTIC
|
Chemical that
retards the growth of microorganisms.
|
|
APPROACH
|
Temperature
difference, in degrees, between the water
leaving a cooling tower and the wet bulb
temperature of the air entering the cooling
water.
|
|
AQUEOUS
|
Using water as a
solvent.
|
|
ASME
|
American
Society of Mechanical Engineers.
|
|
ATOM
|
The smallest unit
of matter retaining the characteristics of an
element.
|
|
ATOMIC
WEIGHT
|
Method of
comparing weight of an atom with that of an
oxygen atom. Oxygen has an atomic weight
of 16; hydrogen has an atomic weight of 1.
|
|
ATTRITION
|
Breakage or wear
of ion exchange resins.
|
|
AUTOCLAVE
|
A chamber for
sterilizing with steam under pressure.
|
|
B
|
Back
to Index |
|
BACK
PRESSURE
|
Pressure exerted
against a flow.
|
|
BACKWASH
|
Upward flow of
water through a resin bed to cleanse, expand
and classify the resin.
|
|
BACTERIA
|
Large group of
one cell microorganisms. Some strains
can produce very adhesive, dense slime type
deposits on waterside surfaces of heat
exchanger in cooling system.
|
|
BASE
|
The hydroxyl form
of a cation or a compound that can neutralize
an acid.
|
|
BASIN
|
Lower area of
system which system water collects, i.e.,
bottom area of cooling tower.
|
|
BED
|
Area in an ion
exchanger containing resin or exchange medium.
|
|
BED DEPTH
|
Height of
resinous material in bed exchanger after
exchanger has been properly conditioned for
operation.
|
|
BED
EXPANSION
|
Effect produced
during backwashing of exchanger.
|
|
BED
VOLUME
|
The amount of
space occupied by the resin bed in cubic feet
or gallons.
|
|
BHP
|
See BOILER
HORSEPOWER.
|
|
BICARBONATE
ALKALINITY
|
Presence in a
solution of hydroxyl (OH-) ions resulting from
the hydrolysis of carbonates and bicarbonates.
|
|
BINDER
|
Substance which
causes particulates to bond together.
|
|
BIOCIDE
|
Group of internal
chemical treatments used to control growth of
microorganisms (algae, bacteria, fungi) in
cooling tower and closed loop systems.
|
|
BIOFILM
|
An aggregate of
microorganisms in which cells adhere to each
other and/or to a surface.
Biofilms may form on living or non-living
surfaces, and represent a prevalent mode of
microbial life in natural, industrial and
hospital settings.
|
|
BIOLOGICAL
DEPOSIT
|
Deposits of
microorganisms, or by-products of their life
processes, on waterside surfaces.
|
|
BLEED
|
Intentional
draining of a portion of system water from
cooling tower recirculating system to
drain. Means of controlling
concentration of dissolved solids in system
water.
|
|
BLEED
RATE
|
Rate at which
water is bled from cooling tower recirculating
system.
|
|
BLISTER
|
Partial or
complete failure of boiler tube due to
overheating.
|
|
BLOWDOWN
|
Intentional
wasting or draining of water from boiler
system to waste. Means to removing
sludge from system and also controlling
concentration of dissolved solids in system
water.
|
|
BOD
|
Also known as
Biological Oxygen Demand, a chemical
procedure.
|
|
BOILER
CODE
|
A set of rules
and specifications for designing,
constructing, inspecting and operating
boilers.
|
|
BOILER
HORSEPOWER
|
By definition,
the generation of 34.5 lbs. steam/hour from
and at 212F°. By common acceptance, 10
sq. ft. of heating surface is one rated power
horsepower.
|
|
BRINE
|
A salt solution,
generally sodium chloride.
|
|
BTU
|
Stands for British
Thermal Unit.
|
|
C
|
Back
to Index |
|
Ca
|
Chemical symbol
for calcium.
|
|
CaCO3
|
Chemical symbol
for calcium carbonate.
|
|
CaH
|
Symbol for
calcium hardness.
|
|
CALCIUM
BICARBONATE
|
Results of
chemical reaction between carbon dioxide,
calcium carbonate and water.
|
|
CALCIUM
CARBONATE
|
The precipitant
resulting from heating of the water that
contains calcium bicarbonate.
|
|
CAPACITY
|
Absorption
ability possessed by ion exchange material.
|
|
CARBON
DIOXIDE
|
Corrosive gas
found in most surface and ground water
supplies. Released in the chemical
reactions that occur in boiler system water.
|
|
CARBONATE
ALKALINITY
|
See "P"
ALKALINITY.
|
|
CARBONATE
CYCLE
|
A method of
internal boiler water treatment in which
calcium carbonate is precipitated in the
presence of an organic polymer dispersing
agent.
|
|
CARBONIC
ACID
|
Acid produced
from the mixture of carbon dioxide and water.
|
|
CARRY
OVER
|
Condition which
develops in boiler water resulting in solids
and/or chemical treatment being carried out of
the system as part of the steam.
|
|
CATALYSIS
|
Addition of a
material (catalyst) that does not take a
direct part in a chemical reaction, but serves
to increase the rate of the reaction.
|
|
CATHODE
|
Region of higher
potential in a corrosion cell.
|
|
CATHODIC
INHIBITOR
|
Corrosion
inhibitor that forms a protective film on the
cathode surface of a corrosion cell.
|
|
CATHODIC
POLARIZATION
|
Method of
inhibiting corrosion by preventing the
diffusion, or flow of oxygen, to the cathode
site of a corrosion cell.
|
|
CATION
|
Ion which carries
a positive electrical charge.
|
|
CAVITATION
|
Metal attack
resulting from high flow velocity, variable
pressure situations in water containing
dissolved or entrained gas.
Evidence of cavitations is often deep circular
pits.
|
|
CENTRIFUGAL
SYSTEM
|
Compressor type
cooling system.
|
|
CHANNELING
|
The
flow of water or solution taking the "least
line of resistance" through a resin bead.
|
|
CHELANT
|
A
sequestrant that prevents an ion from
exhibiting its normal properties by complexing
(bonding) with it.
|
|
CHEMICAL
OXYGEN DEMAND
|
Amount of oxygen,
expressed in parts per million, consumed under
specified conditions in the oxidation of
organic matter contained in water.
|
|
CHLORIDE
|
Acid radical
contained in both surface and ground water
supplies.
|
|
CHLORIDE
TEST
|
Test performed on
water sample to determine total amount of
chlorides present. Results expressed in
ppm. Recommended upper limits to
which chlorides can build in system water
provides a method for controlling waterside
deposits. Amount of chloride in system
water compared to chloride content of makeup
or feedwater, provided the means of
determining 'cycles of concentration' at which
a system is operating.
|
|
CHLORINATED
PHENOLIC
|
Non-oxidizing
biocide used to control growth of
microorganisms in cooling tower recirculating
system water.
|
|
CHLORINATOR
|
A device used to
meter chlorine into a cooling water at a
preselected rate.
|
|
CHLORINE
|
Oxidizing type
biocide. Used to control growth of
microorganisms in cooling tower system water.
|
|
CHLORINE
DEMAND
|
Amount of
chlorine, expressed in parts per million,
required to achieve chlorination.
|
|
CHLORINE
RESIDUAL
|
Amount of
available chlorine present in the system water
at any specific time.
|
|
CHROMATE
|
Anodic type
corrosion inhibitor that forms a highly
passive film of ferric and chromate oxide on
the anode of a corrosion cell.
|
|
CIRCULATING
HOT WATER SYSTEM
|
System in which
water is heated and circulated through a
system of piping, or to a heat
exchanger. In circulating through the
system, heat in water is transferred and
utilized for space heating, heating of potable
water and/or used to clean and sanitize.
|
|
CLARIFICATION
|
External
treatment processes which removes suspended
solids, turbidity, color and colloidal matter
from makeup water.
|
|
CLOSED
SYSTEM
|
System in which
water is continuously recirculated and loss of
water from the system is less than 5% of
recirculating rate.
|
|
COAGULATION
|
To bring together
small particles into a single large mass which
can be filtered or settled out of solution.
|
|
COALESCENCE
|
Process
describing the growing together of several
different particulates into one larger body.
|
|
COD
|
Abbreviation for
CHEMICAL
OXYGEN DEMAND.
|
|
COGENERATION
|
The production of
both steam and electricity in the same plant.
|
|
COLLODIAL
|
Composed of
extremely small size particles which are not
removed by normal filtration.
|
|
CONC
|
Abbreviation for
concentration.
|
|
CONDENSATE
|
Water condensed
from steam.
|
|
CONDENSATE
POLISHER
|
Ion exchange
resins being used to remove or exchange ions
as well as to filter condensate for reuse in
steam cycle.
|
|
CONDENSATE
TANK
|
Tank or reservoir
in a steam boiler system to which condensate
flows and collects.
|
|
CONDENSER
|
Heat exchanger in
cooling system in which refrigerant gas gives
up heat to tower recirculating water.
|
|
CONDUCTANCE
|
A measure of the
ability of water to conduct an electric
current.
|
|
CONDUCTIVITY
|
The ability of
electrical current to flow through water as a
measure of its ion content in mhos/cm or
micromhos/cm.
|
|
CONDUCTIVITY
TEST
|
Test made on any
water sample with a conductivity meter to
determine amount of total solids
present. Results expressed in
'micromhos', 'mho' or
'conductivity'. Test results are
utilized to control solids in system water
within limits to prevent deposition.
|
|
CONTAMINATE
|
Any solid, gas or
liquid in system water that is foreign and not
normally found under the conditions of
operation.
|
|
CONTINUOUS
BLOWDOWN
|
Intentional,
controlled, continuous flow of boiler system
water taken from the top or upper section of
boiler to drain.
|
|
CONVECTION
|
Transference to
heat by circulation of the heated parts of gas
or liquid whereby heated portions are lighter
and rise vertically.
|
|
COOLING
POND
|
Large body of
water (pond or small lake) to which cooling
water is pumped and heat contained in water is
released to atmosphere by natural evaporation.
|
|
COOLING
RANGE
|
Numerical
difference between temperature of water
entering top of cooling tower and the
temperature of water leaving the basin or sump
of the tower.
|
|
COOLING
TOWER
|
Device for the
evaporative cooling of water by contact with
air. Achieved partially by an exchange
of latent heat resulting from evaporation of
some of the circulating water, and partially
by transfer of sensible heat to the air.
|
|
COPOLYMER
|
Polymerization of
different monomers on the backbone of a
polymer or on its branch chains.
|
|
CORROSION
|
Electrochemical
process in which a difference in electrical
potential develops between metals or between
different sites of the same metal. The
difference in potential results in metal being
removed at the anode site.
|
|
CORROSION
CELL
|
Two points on
different metals, or different sites of the
same metal, consisting of an anode and
cathode. Difference in electrical
potential between the two points results in
metal being removed at the anode site.
|
|
CORROSION
COUPON
|
Test metal strip
used to measure the rate of corrosion.
|
|
CORROSION
PRODUCTS
|
Metal removed as
a result of the corrosion process.
|
|
CORROSION
STRIP
|
See CORROSION
COUPON.
|
|
COUNTER
FLOW TOWER
|
Tower where air
movement and hot water mix at 180°to each
other with air moving vertically through tower
fill packing.
|
|
CREVICE
CORROSION
|
Corrosion taking
place where specific area is isolated from
bulk solution, i.e., flange area.
|
|
CROSS
CONTAMINATION
|
Intermixing of
one resin with another of an opposite charge
or of two water streams.
|
|
CROSS
FLOW TOWER
|
Tower in which
air movement and hot water mix at 90°or cross
to each other with air moving horizontally
through the fill packing and falling water.
|
|
CROSS
LINKAGE
|
The connection
between two or more polymer chains to tie them
together, as is done by DVB.
|
|
Cu
|
Chemical symbol
for copper.
|
|
CUPROUS
METAL
|
Metal containing
copper.
|
|
CUPROUS
OXIDE
|
Passivated oxide
state of copper.
|
|
CYCLES OF
CONCENTRATION
|
Ration between
the amount of dissolved solids in makeup water
and amount of dissolved solids in system
water.
|
|
CYCLOHEXYLAMINE
|
Neutralizing type
amine. Used to help control rate of
corrosion in condensate return system of steam
boiler.
|
|
D
|
Back
to Index |
|
DEAERATOR
|
External
treatment equipment in which boiler feedwater
is heated to 212F°+ for the purpose of
releasing dissolved oxygen from the water.
|
|
DEALKALIZATION
|
External
treatment process by which natural alkalinity
or raw makeup water is lowered.
|
|
DEFOAMER
|
See ANTIFOAM.
|
|
DEIONIZATION
|
General term
which embraces the removal of all charge
ionizable salts (both organic and inorganic)
from solution.
|
|
DEIONIZE
|
To remove ions
from solution.
|
|
DEIONIZER
|
External
treatment process in which raw makeup water,
under pressure, passes through a membrane and
in the process dissolved solids are removed.
|
|
DELINGNIFICATION
|
Loosening of
surface fibers in cooling tower wood members
causing a weakening of the timber.
|
|
DEMINERALIZE
|
Removal from
solution or inorganic salts by means of
adsorption by ion exchange.
|
|
DEPOLARIZATION
|
Any change in the
potential of either the anode or cathode or
both, which increases the driving force of the
corrosion reaction.
|
|
DEPOSITION
|
General term
describing accumulation of matter on waterside
surface of heating or cooling
equipment. Can be hard scale,
sludge, iron oxide, foulants, biological
deposits.
|
|
DESIGN
TONNAGE
|
Parameters for
which a cooling tower is built.
Expressed as cooling a given GPM flow of water
entering the tower at a specified
temperature-cooling through a given
range-leaving the tower at the required
temperature.
|
|
DEVELOPED
TONNAGE
|
Actual amount of
cooling being performed by system.
If system was designed for a 10°cooling range,
and water falling through tower is cooled by
5°F, system would have developed tonnage of
50%.
|
|
DEW POINT
|
Temperature at
which a given mixture of air and water will
have a relative humidity of 100% saturation.
|
|
DEZINCIFICATION
|
Leaching of zinc
from brass.
|
|
DI
WATER
|
Useable discharge
from dionizer.
|
|
DIFFUSION
|
Spontaneous
process of equalization of physical states,
i.e., one gas liberated in another.
|
|
DISCICCANT
|
Moisture
absorbing material, i.e., quick lime, silica
gel, activated alumina. Used to control
condensation in boiler during dry lay-up.
|
|
DISPERSANT
|
Chemical which
causes particulates in water to remain in
suspension.
|
|
DISSOCIATE
|
The process of
ionization of an electrolyte or a salt upon
being dissolved in water, forming ions of
cation and anion.
|
|
DISSOLVED
MATTER
|
Matter, exclusive
of gases, present in water.
|
|
DISSOLVED
OXYGEN
|
Oxygen which has
been freed from compounds contained in natural
water supplies.
|
|
DISSOLVED
SOLIDS
|
Minerals in
surface and ground water supplies which have
been dissolved from contact with earth’s
surface.
|
|
DISTRIBUTION
DECK
|
Area on top of
cooling tower into which water, containing
heat, is dumped.
|
|
DISTRIBUTION
SYSTEM
|
Mechanical method
of uniformly distributing hot water over the
fill area inside the tower preparatory to
cooling. Low pressure spray
through the piping and nozzles is normally
used in counter-flow tower, and gravity drop
in cross-flow tower.
|
|
DRIFT
|
Water droplets
which are entrained in the airstream as it
passes through the tower. Water
entrained is carried out of the tower and lost
to the atmosphere.
|
|
DRIFT
ELIMINATOR
|
Baffling in
cooling tower that causes hot air, with
entrained droplets, to change direction a
number of times causing the droplets to hit
eliminator surfaces and fall back into the
tower water.
|
|
DRUM VENT
|
Valve on the top
of boiler drum. Used to vent air from
boiler at "start up" or when boiler is cooling
down.
|
|
DRY BULB
|
Ambient
temperature of air measured in standard manner
with conventional instruments.
|
|
DRY
LAY-UP
|
Period during
which equipment or system is non-operational
and all water drained and system is left dry.
|
|
DS
|
Abbreviation for
dissolved solids.
|
|
E
|
Back
to Index |
|
ECONOMIZER
|
Heat exchanger
placed in gas passage between boiler and
stack. Designed to recover heat.
|
|
EDTA
|
Abbreviation for
ETHYLENEDIAMINE
TETRAACETIC ACID. Chemical
referred to as a "chelant". Forms heat
stable complex with calcium, magnesium, iron
and copper.
|
|
EDUCTOR
|
A device that, by
flow of water through it creating a vacuum,
draws a solution into the water stream passing
through it.
|
|
EFFLUENT
|
Flow of water out
of a tank or from system.
|
|
ELECTRIC
BOILER
|
Unit for
production of steam by heating water with
electrical resistance elements, or by passing
AC current through the water between
electrodes.
|
|
ELECTRODES
|
Conductive
materials placed in water solution which have
a positive or negative charge.
|
|
ELECTROLYTE
|
Material that
when dissolved in water form ions which are
capable of carrying current.
|
|
ELECTRON
|
A sub atomic
particle with a negative electrical charge.
|
|
ELECTRONEUTRALITY
|
Where the
positive electrical charge equals the negative
charge.
|
|
ELUTION
|
To remove ions
from a resin by passing other ions in solution
of higher concentration or affinity through
the resin bed.
|
|
EMULSION
|
A colloidal
dispersion of one liquid in another.
|
|
ENTHALPY
|
Total heat
content, which is the sum of the sensible heat
of the air and water vapor, plus the latent
heat of vaporization of the water.
|
|
ENTRAINED
|
To carry or draw
along. The transport of water in a gas
or vapor stream.
|
|
EQUATION
|
An expression of
a reaction using chemical symbols.
|
|
EQUILIBRIUM
|
The stage in a
reversible reaction when there is no driving
force in either direction.
|
|
EQUILIBRIUM
REACTIONS
|
Interaction of
ionizable compounds in which the products
obtained tend to revert to substances from
which they were formed until a balance is
reached in which both reactions and product
are present in definite ratios.
|
|
EQUIVALENT
|
Equal valance.
|
|
EROSION
|
Form
of corrosive attack associated with metal
removal due to high water velocity.
|
|
ETHYLENEDIAMINE
TETRAACETIC ACID
|
See EDTA.
|
|
EUTROPHICATION
|
The
process by which a lake ages.
|
|
EVAPORATION
LOSS
|
Portion
of tower recirculating water lost to the
atmosphere in the process of rejecting heat
from tower recirculating water. Amount
lost varies depending on level of heat
contained in tower water.
|
|
EVAPORATIVE
CONDENSER
|
System in which
condenser or heat exchanger is located in the
cooling tower. Water is sprayed from
nozzles above condenser, while air is blown
across condenser tubes or coil.
Refrigerant, inside condenser tubes, is cooled
due to the extraction of heat from the
refrigerant gas caused by the evaporation of
water on the outside of the condenser tubes.
|
|
EVAPORATIVE
COOLING
|
Cooling by
evaporation of water, heat for which is
supplied by air.
|
|
EVAPORATOR
|
Heat exchanger in
which chill water or air gives up heat it
contains to refrigerant gas.
|
|
EXCHANGE
SITE
|
Reactive groups
on an ion exchange resin.
|
|
EXHAUSTION
|
State in which
resin in water softener is no longer capable
of ion exchange.
|
|
EXOTHERM
|
Giving off heat
in reaction or solution of a substance.
|
|
EXTERNAL
TREATMENT
|
Any process of
procedure which removes or reduces solids or
gases from water before it enters the boiler
or cooling tower system water.
|
|
EXTRAPOLATION
|
Extending
information beyond the point where proven data
is available.
|
|
F
|
Back
to Index |
|
FAN
|
An air foil
rotating to move air through cooling
tower. Mounted on top of tower (induced
draft) or side of tower (forced draft).
|
|
FAN STACK
|
Tower fan
housing.
|
|
Fe
|
Chemical symbol
for iron.
|
|
FEEDWATER
|
Water feed to
boiler. Can be a mixture of condensate and raw
makeup, all condensate, or all raw makeup
depending on operating conditions.
|
|
FERRIC
OXIDE
|
Metal removed in
corrosion of iron bearing metal.
|
|
FERROUS
METAL
|
Metal constructed
from iron, i.e., cast iron, nickel, iron,
galvanized steel, silicon, stainless steel.
|
|
FILL
|
Structural
material within cooling tower that facilitates
contact between water and air. See FILL PACKING, SLATS, SPLASH
PACKING, TOWER
FILL.
|
|
FILL
PACKING
|
Fill material
such as cross-fluting designed to distribute
water in thin film in a cooling tower.
|
|
FILMING
AMINE
|
Class of
inhibitor used to control corrosion in
condensate return portion of steam boiler
system. Forms an adherent non-wettable
organic film on metal surface thereby
preventing contact between metal surface and
corrosive condensate water.
|
|
FILMING
INHIBITOR
|
General term
applied to any treatment which forms an
adherent non-wettable film on metal surface
preventing contact between metal and system
water.
|
|
FILTER
|
Porous media
through which a liquid may be passed to effect
removal of suspended matter.
|
|
FILTRATE
|
Liquid which
passes through a filter.
|
|
FILTRATION
|
External
treatment process in which water passes over a
filter bed of granular material to effect
removal of suspended matter.
|
|
FINES
|
Resin particles
smaller than 50 mesh.
|
|
FIRE TUBE
BOILER
|
Term used to
describe a boiler in which tubes are
surrounded by water and fire, and gases pass
through inside of boiler tube.
|
|
FLASH
TANK
|
Tank into which
blowdown from boiler is introduced. Part
of water flashes into steam; remainder is
removed from tank as a liquid.
|
|
FLOC
|
Clump of solids
formed in water.
|
|
FLOCCULANT
|
Chemical which
attaches itself to foulant particles creating
a low density, light, fluffy floc that will
have little tendency to adhere to metal
surfaces. Floc usually settles or
precipitates in the solution.
|
|
FMA
|
Abbreviation for
free mineral acid or, sum of the mineral
acids.
|
|
FOAMING
|
Small, stable,
noncoalesing bubbles formed on water surface
in boiler. Extreme foaming is leading
cause of ‘carryover’.
|
|
FOG
|
Symbol for fats,
oil and grease in water analysis.
|
|
FORCED
DRAFT TOWER
|
Type of cooling
tower in which air intake is at bottom and air
is forced up and through tower.
|
|
FOULANT
|
Term loosely used
to define any type deposit composed of silt,
organics, particulates scrubbed from
atmosphere, microbiological deposition, dirt,
etc.
|
|
FREE
AVAILABLE CHLORINE
|
Refers to any
unreacted chlorine present in system water.
|
|
FREE BASE
|
The regenerated
form of a weak base anion resin.
|
|
FREE CO2
|
Dissolved carbon
dioxide gas in water.
|
|
FREEBOARD
|
The space above
the resin bed to accommodate resin expansion
in backwash step of regeneration.
|
|
FUNGICIDE
|
Chemical that
kills fungi.
|
|
FUNGUS
|
A simple plant,
containing no chlorophyll and not
differentiated into roots, stems or leaves.
|
|
G
|
Back
to Index |
|
GALVANIC
CORROSION
|
Corrosion that
occurs when two dissimilar metals are in
contact with solution.
|
|
GALVANIC
SERIES
|
Table listing
metals according to their ability to resist
corrosion.
|
|
GENERAL
CORROSION
|
Metal attack that
is uniformly distributed over a surface.
See UNIFORM
CORROSION and UNIFORM
THINNING.
|
|
GPD
|
Symbol for
gallons per day.
|
|
GPG
|
Symbol for grains
per gallon.
|
|
GPH
|
Symbol for
gallons per hour.
|
|
GRAPHITIZATION
|
Selective loss of
iron from cast iron.
|
|
GRAVIMETRIC
|
Measurement by
weight.
|
|
GREENSANDS
|
Neutrally
occurring materials composed primarily of
complex silicates, which possesses ion
exchange properties.
|
|
GROOVING
|
Term describing
corrosion of condensate piping due to carbonic
acid attack. Characterized by
development of a groove or flat area in the
bottom portion of condensate piping.
|
|
GROUND
WATER
|
Portion of water
which percolates into the earth's crust and
collects in subterranean pools and underground
rivers. Source of well and spring water.
|
|
H
|
Back
to Index |
|
H
|
Symbol for
hardness.
|
|
HANDHOLE
|
An opening in
boiler drum or water leg which permits limited
visual inspections of internal waterside
surfaces.
|
|
HARDNESS
|
A characteristic
of water quality generally accepted to
represent the total concentration of calcium
and magnesium ions.
|
|
HARDNESS
TEST
|
Test performed on
water sample to determine the presence or
absence of the elements of calcium or
magnesium. Results expressed in
ppm. Calcium and magnesium minerals are
the principal cause of scale deposits.
|
|
HEAT
EXCHANGER
|
Equipment in
which heat is transferred from one medium to
another.
|
|
HEAT LOAD
|
Amount of heat
dissipated in a cooling tower measured in
BTU's.
|
|
HEAT PUMP
|
Closed loop
system used to extract low-level heat from one
medium, normally air or water, boost its
temperature and release it into another
medium.
|
|
“HIGH
HEAD"
|
Term used loosely
to indicate pressure of refrigerant gas in
compressor higher that it should be at a
specified load condition.
|
|
HIGH
PRESSURE BOILER
|
Relative term
used to indicate boiler operating
pressure. Generally indicates boiler
operating at or above 600 psig.
|
|
HOT WELL
|
Closed or open
tank in which condensate water is stored.
|
|
Hp
|
Stands for
horsepower.
|
|
HYDRAULICS
|
A movement or
action resulting from liquid flow.
|
|
HYDROMETER
|
A device to
measure specific gravity of fluids.
|
|
HYDROPHILIC
|
Term which means
to attract water.
|
|
HYDROPHOBIC
|
Term which means
to repel water.
|
|
HYDROXYL
|
Term used to
describe the OH radical.
|
|
HYPERBOLIC
TOWER
|
Chimney or
natural draft type cooling tower.
|
|
HYPOCHLORITE
|
Basic chemical
containing chlorine.
|
|
I
|
Back
to Index |
|
IMPINGEMENT
|
Metal attack
usually due to turbulent flow of water high in
dissolved or suspended solids or entrained
gases. Results in horseshoe shaped pits.
|
|
INDICATOR
|
Substance that
gives visible change, usually of color, at a
desired point in a chemical reaction.
|
|
INDUCED
DRAFT TOWER
|
Cooling tower
with air mover or fan on top of tower pulling
air through the tower fill and out through the
loop.
|
|
INFLUENT
|
A liquid flow
into a system.
|
|
INHIBITOR
|
Generally used to
indicate any chemical that aids in control of
corrosion. Also used to indicate some
treatments which inhibit scale formation.
|
|
INORGANIC
MATTER
|
Matter composed
of other than plant or animal matter.
|
|
INTERFACE
|
Point where two
substances are in contact one with another.
|
|
INTERLOCK
|
A device which
will prevent one action from happening while
another action is proceeding.
|
|
INTERNAL
TREATMENT
|
Chemical
treatment added to system water to aid in
controlling corrosion, prevention of waterside
deposits or control of microbiological growth.
|
|
ION
|
An atom or
radical in solution carrying an integral
electrical charge either positive (cation) or
negative (anion).
|
|
ION
EXCHANGE
|
The interchange
of one ion in solution with another ion on an
insoluble material.
|
|
IONIZATION
|
Dissociation of
molecules into charged positive or negative
particles.
|
|
IRON
FOULING
|
Plugging of
piping, nozzles, etc. with iron oxide or rust.
|
|
IRON
OXIDE
|
Metal removed in
corrosion process from iron bearing metals.
|
|
IRON
RELATED BACTERIA
|
Uses the
abbreviation of IRB and is a bacteria which
assimilates iron and excretes its compounds in
their life process.
|
|
J
|
Back
to Index |
|
K
|
Back
to Index |
|
L
|
Back
to Index |
|
LANGELIER
INDEX
|
An index used to
determine the scaling or corrosive tendencies
of water.
|
|
LATENT
HEAT
|
Heat required to
change a liquid into a vapor without change of
temperature or pressure.
|
|
LAYERED
OR
STRATIFIED BED
|
Resins with
sufficient difference in density and hydraulic
characteristics to be layered in the same tank
in place of two separate tanks.
|
|
LEAKAGE
OR SLIPPAGE
|
The amount of an
ion or ions coming from a resin bead during
the service cycle.
|
|
LEGIONELLA
PNEUMOPHILA
|
Legionella
pneumophila is a motile, rod-shaped,
gram-negative, aerobic, bacterium. It is
considered to be a "facultative parasite,"
which has been identified as the leading cause
of Legionnaires’ Disease.
|
|
LIGNIN
|
Major
non-cellulose constituent of wood.
|
|
LIME SODA
SOFTNER
|
Water softener
employing calcium hydrate and sodium carbonate
as the reacting chemicals.
|
|
LOAD
|
Term used to
express the amount of steam produced by a
boiler or heat being rejected by a cooling
tower when compared to amount for which system
was designed. If producing or rejecting
one half of its designed or rated capacity,
system is said to be operating at 50% of load.
|
|
LOUVER
|
Baffle used for
purpose of changing the direction of air flow
in a cooling tower. Also to prevent
water droplets from splashing out of cooling
tower on descent through the structure.
|
|
LOW
BOILER PRESSURE
|
Relative term
used to indicate boilers operating below 450
psig.
|
|
M
|
Back
to Index |
|
"M"
ALKALINITY
|
Water in which
hydrogen ions (acid) predominate, causing pH
to be somewhere in a pH range of 4.2-8.4.
|
|
MACROPOROUS
|
Having large
pores.
|
|
MAGNETITE
|
The black
magnetic, protective film of Fe3O4
normally present on surfaces of steel.
|
|
MAKEUP
TUBE
|
Downcomer, supply
tube are common tubes used to indicate tubes
where circulation of water is down.
|
|
MAKEUP
WATER
|
Treated or
untreated water introduced into a system to
replace any losses.
|
|
MANHOLE
|
Opening in boiler
or tank that permits a man to crawl through
for internal inspection.
|
|
MECHANICAL
DRAFT TOWER
|
Cooling tower in
which air is constantly being moved over water
falling through the tower by fans located on
the side of the tower.
|
|
MEMBRANE
|
A barrier,
usually thin, that permits passage only of
particles up to a certain size or of specific
nature.
|
|
METABOLIC
|
Undergoing or
pertaining to a change in state.
|
|
METABOLIZE
|
To convert food,
such as organic matter, to cellular material
and gaseous by products by biological process.
|
|
MHO
|
Abbreviation for
micromho.
|
|
MICROBIOCIDE
|
A chemical toxic
to microorganisms.
|
|
MICROMHO
|
Basic unit of
electrical conductance.
|
|
MICROORGANISM
|
Organisms that
cannot be seen with the naked eye. In
water treatment they usually refer to
organisms that grow in cooling tower
environment, i.e., algae, bacteria, fungi.
|
|
MIL
|
Measurement of
thickness or depth. Term used in water
treatment to express degree of metal loss due
to corrosion.
|
|
MILL
SCALE
|
Matter formed on
iron or steel in the process of
production. Consists mainly of magnetic
iron oxide.
|
|
MIXED BED
DEMINERALIZER
|
External
treatment process consisting of a series or
system of strong cation or strong anion, weak
base anion, mixed bed decarbonator or vacuum
deaerator exchange.
|
|
Mn
|
Chemical symbol
for manganese.
|
|
MOLECULE
|
The smallest unit
of matter retaining properties of a compound.
|
|
MOLYBDATE
|
Filming type of
corrosion inhibitor that forms a passivating
film on the anode of a corrosion cell.
|
|
MONOMER
|
A single reactive
molecule capable of combining with another
like itself or another different monomer to
form a polymer.
|
|
MONOMOLECULAR
|
A film that is
one molecule thick.
|
|
MORPHOLINE
|
Chemical
treatment utilized to neutralize carbonic acid
in condensate return portion of steam boiler
system.
|
|
MPY
|
Abbreviation of
mils per year. Used to express rate of
corrosion.
|
|
MUD DRUM
|
Lower drum of
boiler where insoluble sludge collects.
|
|
N
|
Back
to Index |
|
NACE
|
National
Association of Corrosion Engineers.
|
|
NaCl
|
Chemical symbol
for salt.
|
|
NATURAL
DRAFT TOWER
|
Tower in which
the air movement through it is dependant only
upon atmospheric conditions.
|
|
NEGATIVE
CHARGE
|
Electrical
potential which an atom acquires when it gains
one or more electrons.
|
|
NEUTRAL
|
In pH terms, 7;
neither acid nor alkaline.
|
|
NEUTRALIZING
AMINE
|
A class of
inhibitors that neutralizes carbonic acid by
elevating the pH of condensate water from acid
to an alkaline state.
|
|
NITRATE
|
Nitrogen as
nitrates.
|
|
NITRITE
|
An anodic
inhibitor that induces metal to form its own
impervious film at the anode site in a
corrosion cell.
|
|
NOBLE
METAL
|
Metals that are
insoluble to any pH, i.e., titanium,
molybdenum, nickel.
|
|
NON-FERROUS
|
Metal which does
not contain any iron, i.e., cooper, brass,
zinc, aluminum.
|
|
NON-OXIDIZING
TOXICANT
|
Class of biocide
that function by adsorbing onto the
microorganism's cell wall.
|
|
NOZZLES
|
Water spouts in
distribution decking of a cooling tower.
Breaks up the returning water into droplets
and distributes them uniformly over the top of
the fill.
|
|
NSF
|
National Sanitary
Foundation
|
|
NTA
|
Abbreviation for
Nitrilotriacetic Acid. Used to prevent
scaling in boilers and/or as an acid in
selective metal deposit control, i.e., iron
and manganese in both boilers and cooling
towers.
|
|
O
|
Back
to Index |
|
O2
|
Chemical symbol
for oxygen.
|
|
"OFF THE
LINE"
|
Term used to
denote a system that is in short or long term
layup.
|
|
“OH”
ALKALINITY
|
See "P"
ALKALINITY.
|
|
OHM
|
A unit of
resistance to the passing electric current.
|
|
“ON LINE
STREAM CLEANING”
|
Method of
removing waterside deposits while system
remains in operation.
|
|
ONCE
THROUGH SYSTEM
|
Any system in
which water is only used once and then put to
the drain.
|
|
OPEN
FEEDWATER HEATER
|
Tank in which
feedwater is heated by steam, but where
temperature does not go above atmospheric.
|
|
ORGANICS
|
Carbon containing
compounds generally from vegetation or
non-mineral origin.
|
|
ORGANO-TIN
|
Non-oxidizing
"heavy metal" inorganic biocide used for the
control of microorganisms in system water.
|
|
ORTHOPHOSPHATE
|
1.
Internal chemical treatment that functions as
an anodic inhibitor or antiscalant. 2.
A sludge resulting from the revision of
polyphosphate.
|
|
OSMOSIS
|
Process where
water on one side of a membrane tries to pass
through the membrane to dilute a salt solution
on the other side in an attempt to equalize
the concentration of salt on both sides.
|
|
OXIDATION
|
The addition of
oxygen, the removal of hydrogen, or the loss
of electrons.
|
|
OXIDE
|
A compound
composed of metal and oxygen.
|
|
OXYGEN
|
An element
occurring free as a colorless, tasteless,
odorless gas.
|
|
OXYGEN
SCAVENGER
|
Chemical used in
treatment of boilers to reduce last traces of
dissolved oxygen in system water. Sodium
sulfite most widely used type.
|
|
P
|
Back
to Index |
|
"P"
ALKALINITY
|
Water in which
hydroxyl ions (alkaline) predominate, causing
pH of system water to be above 8.2. Also
referred to as caustic, OH or carbonate
alkalinity.
|
|
PACKAGED
BOILER
|
A shop assembled
steam boiler generator with necessary
auxiliary equipment complete and ready to use.
|
|
PACKING
|
Slats, baffling
or corrugated fill found inside the casing of
a cooling tower.
|
|
PARAMETERS
|
Two figures
indicating an upper and lower limit.
|
|
PARTICULATE
MATTER
|
Any matter,
exclusive of gases, existing in a non-liquid
state of water.
|
|
PASSIVATION
|
The
transformation of a metallic surface to a
state in which it does not readily
oxidize. Usually accomplished by forming
a protective film on metal surface.
|
|
pH
|
A measure of the
concentration of hydrogen ions in water.
pH is a number between 0 and 14, denoting
various degree of acidity or alkalinity.
Neutral water has a pH of 7. Values
below 7 and approaching 0 are increasingly
acid while values from 7 to 14 are increasing
alkaline.
|
|
PHOSPHATE
|
Chemical used in
treatment of boilers that aids in prevention
of scale type deposits.
|
|
PHOSPHONATE
|
1. Cathodic
corrosion inhibitor for ferrous metal.
2. Deposit control agent.
|
|
PITTING
|
Term that
describes localized attack on metal
surface. Results in crater-like
indentations in metal.
|
|
PITTING
FACTOR
|
Ratio of a pit to
the average depth of metal penetration.
|
|
PLANKTONIC
|
Floating or
swimming in water.
|
|
PO4
|
Chemical symbol
of phosphate.
|
|
POLORIZATION
|
Extent of
potential change in volts, caused by net flow
of current to or from an electrode. When
there is no difference in potential between
the anode and cathode, corrosion ceases and
the metal is said to be in a "passive" state.
|
|
POLYACRYLATE
|
Synthetic polymer
formed from monomers. Used as a boiler
and cooling water dispersing agent.
|
|
POLYELECTROLYTE
|
A high molecular
weight water soluble polymer with high charge
density or multi-charged ions.
|
|
POLYMER
|
Synthetic
chemicals with long chain molecules of
repeating units.
|
|
POLYMERIZATION
|
The act of
reacting monomers to form a long chain
polymer.
|
|
POROSITY
|
The degree of
openness or a sponge-like quality.
|
|
POSITIVE
CHARGE
|
The electrical
potential acquired by an atom which has lost
one or more electrons.
|
|
POTABLE
WATER
|
Water which meets
drinking water quality standards.
|
|
PPB
|
Stands for parts
per billion.
|
|
PPM
|
Stands for parts
per million.
|
|
PRECIPITATE
|
Matter that has
separated out of solution as a result of
chemical reaction or physical change.
|
|
PRECIPITATING
PROGRAM
|
A treatment
program that results in precipitation from
solution to scale forming contaminates in the
form of non-adhering sludge.
|
|
PRESSURE
DROP
|
Static pressure
or amount of resistance in air or liquid
caused by system piping or obstructions in
system fabrication.
|
|
PRETREATMENT
|
Any process or
procedure which removes or reduces solids or
gases from water before it enters the system.
|
|
PRIMING
|
Spasmodic actions
resulting in spouting or surging of boiler
water into steam header or outlet.
|
|
PROCESS
STEAM
|
Steam used to
heat or operate some manufacturing process.
|
|
PROCESS
WATER
|
Water used in a
product or in manufacture of a product.
|
|
PUMPING
HEAD
|
Energy required
to raise water and overcome friction losses
inherent in fabrication of the system.
|
|
Q
|
Back
to Index |
|
QUAT
|
Stands for
Quaternary ammonium cations that are
positively charged polyatomic ions of the
structure NR4+, R being
an alkyl group. Unlike the ammonium ion (NH4+)
and the primary, secondary, or tertiary
ammonium cations, the quaternary ammonium
cations are permanently charged, independent
of the pH of their solution.
|
|
R
|
Back
to Index |
|
RADIANT
HEAT
|
Heat supplied by
radiation without necessity of some medium
transmission, i.e., heat from the sun.
|
|
RANGE
|
Numerical
difference between the water temperature
entering the cooling tower at the top, and the
cold water leaving the basin or sump at the
bottom of the tower.
|
|
RATED
TONNAGE
|
Thermal
parameters for which a cooling tower was
designed.
|
|
RAW WATER
|
Natural water as
it comes from the environment or municipal
water treatment plant.
|
|
REAGENT
|
Any substance
which, from its capacity for certain
reactions, is used in detecting, examining or
measuring other substances.
|
|
RECEIVER
|
Tank or reservoir
to which steam condensate flows and makeup
water is introduced into boiler system.
|
|
REGENERANT
|
A chemical used
to restore the ion exchange resin back to its
desired form.
|
|
REGENERATION
|
Process by which
an ion exchanger is restored to its operative
form. Water softener regeneration
involves four steps; backwash, brining, slow
rinse and fast rinse.
|
|
REHEAT
|
Returning
partially expanded steam to a boiler so that
additional heat is added before the steam
passes through the final stages of a turbine.
|
|
RELATIVE
HUMIDITY
|
Ration of water
vapor pressure in the air to the saturated
vapor pressure at the same temperature usually
expressed as a percentage. Also the
number of pounds of water carried by one pound
of dry air.
|
|
RESISTANCE
|
The property of
opposing the flow of electric current.
|
|
RETURN
|
The warm water
returned to top of cooling tower.
|
|
REVERSE
OSMOSIS
|
The reverse flow
of water through a membrane by applying
pressure to overcome osmotic pressure.
|
|
RINSE
|
Step in
regeneration of an ion exchanger.
|
|
RISER
|
The vertical
section of piping that carries hot water to
the top of the cooling tower.
|
|
RO
|
Abbreviation for
reverse osmosis.
|
|
RYZNAR
STABILITY INDEX
|
An index to
determine the scaling and corrosion tendencies
of water.
|
|
S
|
Back
to Index |
|
SAC
|
Abbreviation for
strongly acidic cation resin.
|
|
SALINITY
|
The presence of
soluble minerals in water.
|
|
SAPONIFICATION
|
The hydrolysis of
a fat or alkali.
|
|
SATURATED
|
The maximum
amount of a substance that can be put into the
solution.
|
|
SATURATED
STEAM
|
Steam that is
saturated with heat at a particular
temperature and pressure.
|
|
SBA
|
Abbreviation for
strongly basic anion resin.
|
|
SCALE
|
A hard adherent,
crystalline layer or layers. By analysis
usually contains well over 50% of calcium and
magnesium.
|
|
SCALE
INHIBITOR
|
Term broadly used
when referring to any treatment that reacts
with calcium or magnesium ions preventing them
from depositing as scale.
|
|
SEDIMENTATION
|
Gravitational
settling of solid particles in a liquid.
|
|
SENSIBLE
HEAT
|
Heat
you can feel. Heat required to change
the temperature of air or water.
|
|
SEQUENTIAL
|
One
action occurring followed by others in a given
order.
|
|
SEQUESTRANT
|
Term
used that describes any chemical that forms a
stable, water soluble complex.
|
|
SESSILE
|
Permanently
fixed or unable to move.
|
|
SETTLEABLE
MATTER
|
Matter
that will settle out of solution by gravity
under low flow conditions.
|
|
SHOCK
FEED
|
Introduction
of a large quantity of chemical treatment into
system water within a very short period of
time. Term usually used to describe feed
of biocide into tower cooling system.
|
|
SHOT
FEED
|
Chemical
feed system in which water flow, from high to
low pressure side, forces chemicals from a
feed tank into the system.
|
|
SIGHT
GLASS
|
Glass
tube mounted on outside of boiler indicating
the water level within the boiler.
|
|
SILICA
|
Element found in
water.
|
|
SIO2
|
Chemical
symbol for silica.
|
|
SKIMMER
|
See
CONTINUOUS
BLOWDOWN.
|
|
SLATS
|
Thin
strips of wood or plastic suspended from
frames inside cooling tower.
|
|
SLIME
|
A
soft, sticky mucus-like substance originating
from bacterial growth.
|
|
SLIMICIDE
|
Another
term for biocide.
|
|
SLUDGE
|
Matter
in solution or matter that collects at the
bottom of boiler drum.
|
|
SLUDGE
CONDITIONER
|
Natural
or synthetic treatment that aids in preventing
coagulation of system water particulates into
a large floc or mass.
|
|
SLUG FEED
|
See SHOT
FEED.
|
|
SO3
|
Chemical
symbol for sulfite.
|
|
SODIUM
CHROMATE
|
Filming
type corrosion inhibitor
|
|
SODIUM
SILICATE
|
Anodic
corrosion inhibitor that hydrolyzes in water
to form negatively charged colloidal particles
which migrate to anodic site of corrosion
cell.
|
|
SODIUM
SULFATE
|
By
product of reaction between sodium sulfite and
dissolved oxygen.
|
|
SODIUM
SULFITE
|
Treatment
used to aid in reducing dissolved oxygen in
steam boiler system.
|
|
SOFT
WATER
|
Water
that contains little or no calcium or
magnesium.
|
|
SOFTENER
|
External
treatment process in which calcium and
magnesium (hardness) are removed and replaced
with sodium by cation exchange.
|
|
SOLUBILIZING
PROGRAM
|
A
deposit control program in which deposit
forming cations are complexed (tied up), held
in solution and dispersed in colloidal form in
system water.
|
|
SOLUBLE
OIL
|
Anodic
inhibitor that forms negatively charged
particles which migrate to anode of corrosion
cell and precipitate, with metal ions, onto
the anode site.
|
|
SOY
AMINE
|
An acceptable food
grade FILMING
AMINE. |
|
SPECIFIC
GRAVITY
|
The
ratio of the weight of a given volume of a
substance to the weight of an equal volume of
water at a fixed temperature.
|
|
SPECIFIC
RESISTANCE
|
The
resistance between opposite faces of a one
centimeter cube of a given substance and
expressed in ohm-cm3.
|
|
SPLASH
PACKING
|
Type
of cooling tower fill consisting of slats so
arranged that water falling through the tower
is broken up into small droplets thus
achieving better contact with air.
|
|
SPORE
|
A
cell in a resistant envelope, capable of
developing into a normal organism.
|
|
SPRAY
FILLED TOWER
|
Cooling
tower in which breakup of water is dependent
solely on spray nozzles.
|
|
SPRAY
POND
|
System
in which hot water in a cooling tower is
pumped to a large pond or small lake, sprayed
into the atmosphere through nozzles, and
cooled by natural evaporation.
|
|
SRB
|
See
SULFATE
REDUCING BACTERIA.
|
|
SS
|
Chemical
symbol for suspended solids.
|
|
STABILITY
INDEX
|
See
RYZNAR
STABILITY INDEX.
|
|
STABLE
WATER
|
Water
which is neither scale forming nor corrosive.
|
|
STAGE
HEATER
|
Device
for heating feedwater.
|
|
STAND BY
|
Period
during which system or equipment serves as a
"back up".
|
|
STATIC
|
An ion exchange
reaction occurring with a volume of liquid in
contact with a volume of resin.
|
|
STEAM
BOILER
|
Any device for
the production of steam under pressure.
|
|
STEAM
DRUM
|
The
upper boiler drum where steam is produced and
withdrawn.
|
|
STEAM
GENERATOR
|
See
STEAM BOILER.
|
|
STEAM
HEADER
|
Large pipe,
usually located on top of steam drum, through
which steam exits a boiler.
|
|
STEAM
PURITY
|
Measurement which
expresses the amount of contamination, either
organic or inorganic, contained in steam.
|
|
STEAM
QUALITY
|
The ratio of the
weight of vapor to total weight of the steam
water mixture.
|
|
STEAM
TRAP
|
A device for
bleeding condensate out of a steam line
without allowing steam to escape.
|
|
STOICHIOMETRIC
|
Chemical reaction
that results in a change in chemical solution.
|
|
STRAINER
|
A screen to
remove matter that would otherwise cause
plugging or deposits.
|
|
SUBSTOICHIOMETRIC
|
1 to 1 ratio
reaction. See STOICHIOMETRIC.
|
|
SULFATE
REDUCING BACTERIA
|
Bacteria which
assimilate oxygen from sulfate compounds,
reducing to sulfide.
|
|
SULFITE
TEST
|
Daily test
performed on boiler system water to determine
the amount of sodium sulfite present.
Results expressed in ppm. When sulfite
residual is within prescribed range-usually
20ppm-60ppm, it is assumed no dissolved oxygen
is present and therefore, 'pitting' type
corrosion is under control.
|
|
SUMP
|
See BASIN.
|
|
SUPER
CRITICAL BOILER
|
Boiler operating
at a pressure higher than the critical
pressure, 3203.6 psig.
|
|
SUPER
HEAT
|
The number of
degrees Fahrenheit of steam above the
temperature of saturated steam at some
specified pressure.
|
|
SUPER
HEATER
|
Tubes within a
boiler through which saturated steam passes
after leaving a boiler and where steam absorbs
additional heat.
|
|
SUPER
SATURATED
|
To contain more
in solution than normal for a given
temperature.
|
|
SUPPLY
|
Cooled water
flowing from the basin or sump of a cooling
tower.
|
|
SUPPORT
MEDIA
|
A graded particle
size, high density material such as gravel,
anthrafil, quartz, etc. used to support the
resin bed.
|
|
SURFACE
BLOWDOWN
|
See CONTINUOUS
BLOWDOWN.
|
|
SURFACE
TENSION
|
The resultant
attractive forces on molecules at the surface
of a liquid, exerted by molecules within the
liquid, that tends to make the surface contact
to the smallest possible area.
|
|
SURFACE
WATER
|
Water which has a
short contact with the earth's surface
collecting in streams, rivers, lakes and
reservoirs.
|
|
SURFACTANT
|
Chemical that
alters the surface and interfacial tension.
|
|
SURGING
|
See PRIMING.
|
|
SUSPENDED
MATTER
|
1. Finely
dispersed particles of impurities of water,
including industrial waste, silt, and organic
substances. 2. Mineral salts
(hardness) that has precipitated out of
solution due to the heat or other influences.
|
|
SYMBOSIS
|
Relationship
between a microorganism and a host that is
beneficial to both.
|
|
SYNERGISM
|
1. A
cooperative effort between two or more species
of bacteria resulting in something the
individual species could not accomplish
alone. 2. Blending together
of two or more chemicals so that the total
effect is greater than the sum of the single
effect taken separately.
|
|
T
|
Back
to Index |
|
TDS
|
Chemical symbol
for total dissolved solids. See TOTAL
DISSOLVED SOLIDS.
|
|
TH
|
Chemical symbol
for total hardness.
|
|
THRESHOLD
TREATMENT
|
Control of scale
type deposits by feeding of a
sub-stoichiometric dosage of treatment to
system water.
|
|
TITRATE
|
Determining the
amount of a substance in solution by adding a
measured amount of another substance to
produce a desired reaction or end point.
|
|
TOC
|
Total Organics
Carbon is the amount of carbon bound in an
organic compound and is often used as a
non-specific indicator of water quality or
cleanliness of pharmaceutical manufacturing
equipment.
|
|
TON
|
Term used to
express capacity or size of a cooling
system. Equal to 15,000 Btu per hour.
|
|
TONNAGE
|
Term used to
indicate rated capacity of cooling system.
|
|
TOTAL
CHLORINE RESIDUAL
|
Total amount of
chlorine present, without regard to type.
|
|
TOTAL
DISSOLVED SOLIDS
|
Term indicating
the total amount of dissolved solids present
in a water sample. Usually expressed as
TDS in parts per million.
|
|
TOWER
|
See COOLING
TOWER.
|
|
TOWER
CIRCULATION PUMP
|
Pump that
recirculates water to and from the cooling
tower.
|
|
TOWER
FILL
|
Tower which
contains baffling inside used to increase
break-up of water falling through tower into
small droplets or sheets, and also to provide
additional wetted surface.
|
|
TRICHLOROPHENATES
|
Non-oxidizing
microbiocide.
|
|
TS
|
Chemical symbol
for total solids.
|
|
TSS
|
Chemical symbol
for total suspended solids.
|
|
TUBE
|
A hollow metal
cylinder to convey liquids or gases.
|
|
TUBE
SHEET
|
Area in boiler or
heat exchanger to which tubes are affixed or
fabricated.
|
|
TUBERCULATION
|
A hard, dense,
scab-like deposit of metal oxide on metal
surface.
|
|
TURBIDITY
|
A suspension of
very fine colloidal size particulates that
obscures light rays, but requires many days of
sedimentation due to the small particulate
size.
|
|
TURBINE
|
Rotary device,
powered by boiler steam, whose function is to
drive some other rotating piece of equipment.
|
|
TURNOVER
|
The mixing of
lower and upper layers in a lake in spring and
fall. Caused by temperature and density
equalization.
|
|
U
|
Back
to Index |
|
UMHOS
|
Abbreviation for
micromho.
|
|
UNDER
DEPOSIT CORROSION
|
Corrosion that
takes place under any type of deposit due to
the differential aeration or temperature.
|
|
UNIFORM
CORROSION
|
See GENERAL
CORROSION.
|
|
UNIFORM
THINNING
|
Type corrosion in
which metal is uniformly removed and
thinned. Generally associated with metal
exposed to low pH or acid solution.
|
|
USDA
|
United
States Department of Agriculture.
|
|
V
|
Back
to Index |
|
VALANCE
|
The number of
positive or negative charges on an ion.
|
|
VOLATILE
AMINE
|
Treatment used to
aid in control of corrosion in condensate
system of boiler.
|
|
W
|
Back
to Index |
|
WAC
|
Stands for weak
acid cation resin.
|
|
WALL TUBE
|
Tube containing
boiler water that shields refractory furnace
walls by absorbing heat.
|
|
WATER
FORMED DEPOSIT
|
Any accumulation
of insoluble material derived from water or
formed by the reaction of water upon surfaces
in contact with water, i.e., scale, sludge,
corrosion by-products or biological deposits.
|
|
WATER
TUBE BOILER
|
Boiler in which
water is on the inside of the boiler tubes and
flame and gases are on the outside.
|
|
WET BULB
TEMPERATURE
|
Temperature of
saturated air.
|
|
WET LAYUP
|
Period during
which system or equipment is non-operational
and left full of water.
|
|
X,
Y, Z
|
Back
to Index |
|
ZEOLITE
|
A mineral
composed of hydrated silicates of aluminum and
sodium or calcium.
|
|
ZEOLITE
SOFTENER
|
A term loosely
used to designate a sodium regenerated ion
exchange softener.
|
|
ZINC
|
A non-ferrous
metal.
|
