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Adsorptive Cartridge Filters -
See Deodorizing Cycle.
Air Bumping -
Amyl Acetate A dry-side spotting agent used to remove oil
base stains and plastics.
Anionic Detergent System -
A drycleaning detergent that is
negatively charged. These detergents carry water by solubilization. Anionic
detergents are used in charged systems.
Atmospheric Still -
A distillation device that operates without
the need for internal pressure or vacuum. All drycleaning stills designed for
use with chlorinated solvents are atmospheric.
Azeotropic Distillation - The distillation of a mixture with
components having constant maximum and minimum boiling points, with the
components being distilled without decomposition, and in a fixed ratio.
A method used to remove spent powder filtration
material (diatomite) from tubular filters. In this operation, the solvent flow
is reversed to wash the spent filter powder off the tubular filters. See Bumping.
Base Tank -
A solvent storage tank located at the base of a
drycleaning machine. Normally there are two or three of these per machine. One
base tank contains clean solvent and one contains dirty solvent to be
Bath Operation or Bath System - In this drycleaning
solvent system, a fixed quantity of solvent is issued for one operation.
Solvent is not circulated during the wash cycle. Solvent introduced in the
washer is used for the entire load.
Batch Operation -
A drycleaning solvent system in which there is
continuous circulation of drycleaning solvent. Detergent and sometimes water
are added into a wash solvent tank. The entire wash solvent is
charged with detergent (or detergent is injected). The
concentration of detergent in this charged system is one to two percent. This
is also known as Batched Detergent Injection.
Benzine - See Naphtha.
A chemical or chemical mixture used in pre-spotting,
spotting and laundry operations to decolorize stains and soiled areas. There
are two types of bleaches: oxidizing and reducing.
Body Feed - The fresh filter powder (diatomite) added at the
beginning of each filtration cycle in a non-regenerative powder filtration
Boil Down -
The last phase of the solvent distillation process in
which the still kettle temperature is increased to recover additional solvent.
An enclosed vessel in which water is heated and
circulated either as hot water or steam. Drycleaning operations utilize boilers
as a heat and steam source for distillation operations; heating air for drying
operations; pre-cleaning and spotting operations; steam pressing operations;
steam cleaning of equipment, and steam stripping of carbon adsorption units and
Boiler Blowdown Water -
Water generated from the process where
the steam and water is discharged from the boiler. This discharge blowdown is
part of boiler maintenance to prevent scale buildup.
The Discharge of still bottoms/muck from
a distillation unit or muck cooker. The cause of boilover is usually caused by
overfilling the distillation unit/muck cooker but can be caused by operating
the unit at too high a temperature.
Bound Moisture -
Water held and dispersed by a detergent in a
The bottom plate of a steam press. The garment to be
finished (pressed) is placed on the buck.
Bump Action Filters -
See Regenerative Filters.
The removal or dislodging of spent powder filtration
material (diatomite and activated carbon) from flexible tubular filters by
flexing or agitating or by using compressed air (air bumping).
Button Trap -
A drycleaning machine device located in front of
the solvent pump that prevents objects (lint, fasteners, buttons, coins etc.)
from entering the solvent pump.
Butyl Hydroxyl Toluene (BHT) -
An antioxidant commonly added to
petroleum drycleaning solvents to prevent odor problems (odor inhibitor). Some
re-claimed PCE contains BHT as an additive (color inhibitor). Also known as
Butylated Hydroxyl Toluene.
Carbon Adsorber -
A bed of activated carbon into which an
air-solvent vapor stream is routed and which adsorbs the solvent on the carbon.
Carbon adsorption systems can handle high air flow rates with low solvent
concentrations and reduce solvent vapors in exhaust by 95%. Also known as a Vapor Adsorber or Sniffer.
Cartridge Filter -
A replaceable filter used in the wash cycle
consisting of an outer metallic perforated shell enclosing a pleated paper
filter element around a perforated activated carbon or clay-filled canister
having a central perforated center post with a fine-mesh wrap. Cartridge
filters are the most widely used filters in drycleaning today.
Cationic Detergent -
A drycleaning detergent that is positively
charged. Cationic detergents carry water by means of an emulsion. They provide
excellent water-soluble soil removal. These detergents are used in injection
systems. See injection system.
Centrifugal Disc Filter -
See Spin Disc Filter.
Charged System -
A drycleaning solvent/detergent system in which
detergent is added to the solvent or charged as a certain
percentage of the solvent (normally 1 to 2%) to maintain a continuous
concentration of detergent. Charged systems use anionic detergents.
See Refrigerated Condenser.
Classification - In the drycleaning operation, this is the
separation of clothes into similar groups that may be drycleaned together. This
separation involves classifying garments on the basis of their weight, color,
and finish before cleaning. This breakdown assures that clothes cleaned
together are compatible and receive treatment appropriate for their type.
Clean Air Act Amendments (CAAA) -
The 1990 amendments to the
Clean Air Act (1970) added comprehensive provisions to regulate emissions of
toxic air pollutants, acid rain, and substances that threaten the ozone layer.
Additionally, the 1990 amendments added a permit program and greatly
strengthened enforcement provisions and requirements for non-attainment areas,
mobile source emissions, and automotive fuels.
Closed-loop Machine -
A dry-to-dry machine which recirculates
solvent-laden vapor through a primary control system (e.g. refrigerated
condenser) with no exhaust to the atmosphere during the drying cycle. A
closed-loop machine may allow for venting to the ambient air through a local
exhaust ventilation system, such as a door fan, after the drying cycle is
complete and only while the machine door is open.
A filter designed to separate water from
Cold Machine -
See Transfer Machine.
Cold Spotting Board -
A spotting board that is not supplied with
steam. See Spotting Board.
Condensate Water -
Any drycleaning wastewater derived from the
condensation of distilled solvent vapors, dryer vapors, or steam.
A device used to chill hot solvent vapors and recover
liquid solvent. Condensers are generally used during the drying cycle and when
operating the still, muck cooker, or vapor recovery unit.
Constant Pressure Filter -
A powder filtration system in which
constant solvent pressure is exerted on the filter in order to keep the filter
coated with filter powder.
Contact Water -
Any wastewater stream that has been in contact
with drycleaning solvents or drycleaning solvent vapors. Contact water,
therefore, contains solvent.
Converted Machine -
An existing vented drycleaning machine that
has been modified to be a closed-loop machine by eliminating the aeration step,
installing a primary control system, and providing for re-circulation of
solvent-laden vapor with no exhaust to the atmosphere or workroom during the
drying cycle. A converted machine may allow for venting to the ambient air
through a local exhaust ventilation system, such as a door fan, after the
drying cycle is complete and only while the machine door is open.
Cooked Powder Residue -
The waste material generated by cooking
down or distilling muck. Cooked powder residue is a hazardous waste and will
contain solvent, powdered filter material (diatomite), carbon, non-volatile
residues, lint, dyes, grease, soils and water.
See Muck Cooker.
The portion of the drying cycle that begins when the
heating mechanism deactivates and the refrigerated condenser continues to
reduce the temperature of the air recirculating through the drum to reduce the
concentration of solvent in the drum.
The rotating drum of a drycleaning machine or dryer
where the clothes are placed.
Decamethylcyclopentasiloxane - (a.k.a. D5) See GreenEarth.
Deodorizing Cycle -
The last stage of the operation of the
reclaiming dryer. At this point, the air inlet and exhaust valves are opened
and a stream of cool outside air strips away the last solvent vapors. If
properly done, the clothing should be left dry and virtually odor-free. Also
known as Aeration.
Regeneration or stripping of an activated carbon
bed, or any other type of vapor absorber by removal of the adsorbed solvent
using hot air, steam or other means.
An additive routinely added to solvent to assist in
removing water-soluble soils and stains that are not ordinarily soluble in
A petroleum drycleaning solvent
manufactured by Exxon Chemical. DF-2000 is a so-called synthetic petroleum
drycleaning solvent that has a high flash point (137° F). DF-2000 is composed of isoparafins
reportedly primarily C11 C12.
Diatomaceous Earth or Diatomite -
A siliceous powder composed of
the remains of microscopic single cell aquatic plants. It is used as the filter
media in powder filtration systems. This powder builds up on a supporting frame
and forms a porous surface. Also known as Filter Powder.
Digestive Agent -
A pre-cleaning or spotting agent which is a
mixture of enzymes used to digest food and albuminous-type stains.
Disposable Lint Bags
Filter bags designed by Lint-All that replace cloth lint bags or sponge
lint filters in the lint trap in drycleaning machines, to improve
filtration, airflow, maintenance, and the environment.
A process by which solvent is separated from
non-volatile and other impurities by boiling The used or contaminated solvent
is heated and vaporized, then condensed into a solvent/water mixture, which
after separation yields a pure solvent. The contaminants are left behind as a
residue or sludge.
Diverter Valve -
A flow control device that prevents room air
from passing through a refrigerated condenser when the door of the drycleaning
machine is open.
Door Fan -
A local exhaust ventilation system designed to provide
for a minimum 100 fpm inward air velocity or equivalent into the effective door
open area of a drycleaning machine whenever the door is opened, and where the
solvent emissions are controlled by a carbon absorber or equivalent control
prior to venting to the outer air.
Dosimeter Badge -
A device for measuring the amount of organic
vapors a person is exposed to during a set time period, or the vapor
concentration in a given area.
Trade name for drycleaning perchloroethylene
manufactured by Dow Chemical.
The process used to remove soil,
greases, paints and other unwanted substances from articles with organic
Drycleaning Control System - Equipment (e.g. carbon
refrigerated condenser, azeotropic unit, etc.) or an air cleaning device used
to reduce the amount of air pollutants in an air stream prior to discharge to
A home drycleaning product developed by Proctor
& Gamble. Clothing is placed in a bag containing the product and the bag is
placed in a dryer. Vapors, activated from the heat of the dryer penetrate the
clothing and lift the odors and soils from the clothing.
Drycleaning Machine -
A dry-to-dry machine and its ancillary
equipment or a transfer machine system and its ancillary equipment.
Drycleaning Solvent -
Nonaqueous solvents used in the cleaning of
clothing and other fabrics.
See Reclaimer and Tumbler.
Drying Cabinet -
A housing in which materials that have been
previously drycleaned in solvent are dried instead of being dried by tumbling
in a drycleaning machine. Solvent can be recovered from cartridge filters by a
drying cabinet. Air or steam is pulled over cartridges and then routed to a
carbon absorber where it can be recovered by stripping and separation. Also
known as a Steam Cabinet.
Drying Cycle -
The operation used to actively remove the solvent
remaining in the garments after washing and extraction. For closed-loop
machines, the heated portion of the cycle is followed by cool-down and may be
extended beyond cool-down by the activation of a control system. The drying
cycle begins when heating coils are activated and ends when the machine ceases
rotation of the drum.
Drying Efficiency - See Reclamation Efficiency.
Dry-side Spotting Agent
A non-aqueous solvent used to pre-clean or
“spot” non-water soluble stains or soils.
Dry-to-Dry Machine - A drycleaning machine, in which both
cleaning and drying cycles are performed in the same wash wheel. Because the
dry-to-dry machine is completely enclosed during the entire cycle, releases of
solvent fumes to the plant atmosphere are minimized. Also known as a Hot Machine.
Dyna CleanTM System - A drycleaning solvent
purification system that utilizes azeotropic distillation.
Dyna PurTM Process -
A solvent purification process that employs a permanent stainless steel
filter with a fabric lining. Dirt and other contaminants are routinely
backwashed off the filter with clean solvent. The contaminated solvent is
distilled azeotropically to separate the perc from other components. As with
other systems, the solvent/water vapor mixture produced during distillation is
condensed and the solvent and water are separated. The steam condensate
contains soils, other contaminants, and any perc residual is then
EPA Identification Number -
A unique number assigned by EPA to
each generator or transporter of hazardous waste and each hazardous waste
treatment, storage or disposal facility.
A wastewater pre-treatment device that volatilizes
solvent from the waste stream in a single pass prior to discharge. Normally,
the water is filtered through an activated carbon or polymer filter to reduce
Exhaust Damper -
A flow control device that prevents the
air-solvent vapor stream from exiting the drycleaning machine into a carbon
absorber before room air is drawn into the drycleaning machine.
The step that usually follows immediately after the
completion of the wash cycle and drain period. During extraction, the wash
wheel is accelerated to speeds of 350 to 450 rpm, causing much of the solvent
to spin free of the fabric.
A vertical axis centrifuge which removes most of the
drycleaning solvent from the clothing after the wash phase is
Filter Cake -
Filter Muck -
Filter Powder -
See Diatomaceous Earth.
Filter Soap -
An early drycleaning detergent composed of
petroleum sulfonates and other sulfanates. These soaps are soluble in
drycleaning solvent and can therefore pass through filters, hence the name
Pressing of garments to remove wrinkles and restore
each garment to its original size, shape and appearance. Pressing equipment is
heated with superheated steam.
First Generation Drycleaning Machine -
140° Flash Solvent -
A petroleum distillate drycleaning solvent with a higher flash
point (flash point of 140° F) than common petroleum solvents,
thus reducing its fire hazard. The distillation range for this solvent is 350 -
410°F. Also known as 140° F
Flexible Tube Filters -
See Regenerative Filters.
Fourth Generation Drycleaning Machine -
A non-vented, closed loop
process machine (dry-to-dry) with an additional internal vapor recovery device.
The control technologies used in these machines are refrigerated condensers and
Freon 113 -
Fugitive Vapors -
Vapors that escape from process equipment (such
as a drycleaning machine).
Full-size Carbon Unit -
A carbon unit that is used to adsorb
solvent from a drycleaning machine when the vapors are re-circulating or venting
from the drum during the drying cycle (normally used on first and second
General Exhaust Ventilation System -
A mechanical exhaust
ventilation system consisting of fresh air makeup inlets and one or more
exhaust fans in a drycleaning facility, that primarily exhausts a drycleaning
workroom; also used with a room enclosure.
Discoloration of garments caused by soil particles
flocculating or being adsorbed back onto the garment surface. The chief cause
of graying is dirty solvent.
A recently-developed silicone-based drycleaning
solvent (chemical name is decamethylcyclopentasiloxane) developed by General
Electric and offered as an alternative to chlorinated and petroleum-based
drycleaning solvents. Reportedly has a flash point of 170 ° F and a boiling point of
Halogenated-hydrocarbon Detector -
A portable device capable of
detecting vapor concentrations of perchloroethylene and indicating an
increasing concentration by emitting an audible signal or visual indicator that
varies as the concentration changes.
Heating Coil -
A device used to heat the air stream circulated
from the drycleaning machine drum after perchloroethylene has been condensed
from the air stream and before the stream reenters the drycleaning machine
Hot-Head Press -
A type of steam press with a smooth, non-porous
stainless steel head. The head is heated by steam to surface temperatures as
high as 300° F. The hot-head press is
used to finish silks and silk-like fabrics.
Hot Plate Evaporator - A device that utilizes a heating coil to
vaporize (or boil-off) wastewater at a drycleaning facility primarily
separator water and vacuum press water.
Hydrogen Peroxide -
A common oxidizing bleach used in
pre-cleaning and spotting operations. Normally a 3% hydrogen peroxide solution
is used. Hydrogen peroxide is used to remove organic stains.
Inductive Fan -
A fan in a drycleaning machine that draws air
into the machine when the machine door is opened. This reduces exposure to the
drycleaning workers to emissions of solvent vapors.
Injection System -
A drycleaning solvent/detergent system in
which solvent is added to the wheel saturating the garments and then detergent
is injected into the flow line or into the drum by a pump or dump method.
Cationic detergents are used in injection systems.
Insoluble Soil - The most commonly found materials in fabrics and
the bulk of the soils removed in the drycleaning process. Examples include
earth, concrete dust, sand, carbon, ashes, lint, hair and cosmetics, etc. These
soils will not dissolve either in drycleaning solvent or water. Insoluble soils
are removed in the drycleaning machine by lubrication and emulsification.
International Fabricare Institute (IFI) -
A private international
organization headquatered in Silver Spring, Maryland, that represents
professional drycleaners. IFI provides research, testing services, and
education for drycleaners.
Jumbo Split Cartridge Filter -
A cartridge filter (carbon,
carbon-clay mix or carbonless) whose dimensions are 3 1/4 inches by 9 inches.
Jumbo Full Size Cartridge Filter - A cartridge filter (carbon,
carbon/clay mix or carbonless) whose dimensions are 13 1/4 inches by 18 1/8
Kauri-Butanol Value (KBV) -
The solvent-soluble soil removing
capability of a liquid. A solvent with a high KBV values is usually more
efficient in removing oil and grease stains, but a lower KBV value may be safer
on some dyes, adhesives, and trim fabrics.
In contrast to drycleaning which uses a solvent as
the principal cleaning medium, wetcleaning uses water. This process may be used
occasionally by a drycleaner when a drycleanable garment is heavily stained
with water soluble soils. Also known as Wet Wash.
Dust, hair, fibers and other fine particles that accumulate together.
Lint Trap -
A compartment in a drycleaning machine
that utilizes filter media to trap lint in the air stream.
Liquid Carbon Dioxide -
A recently developed alternative to
chlorinated and petroleum-based drycleaning solvents.
Loading Factor -
The optimum weight of clothes that can be
properly cleaned in a particular machine. This takes into account the size of
the wheel (or tumbler), the type of process used, and the solvent used.
Process of identifying garments by attaching tags to
each garment or stamping an identification code onto an inner surface of the
garment. It is the first operation performed in a drycleaning plant.
A wastewater treatment device that sprays drycleaning
wastewater that has been filtered through activated carbon or polymer filter
into the air for disposal.
Muck - The residue from a powder filtration system which consists
of diatomite (diatomaceous earth), spent solvent, non-volatile residues,
greases, lint, soils, water, and sometimes carbon. Also known as Filter
Cake or Filter Muck.
Muck Cooker -
A distillation device in which live steam is used
to heat solvent-laden waste (muck) from powder filtration systems to volatilize
and recover solvent. Also known as a Cooker.
A petroleum or coal tar distillate composed largely of
aliphatic hydrocarbons. Naphtha has been used as a drycleaning solvent. Also
known as Benzine.
National Emission Standards for Hazardous Air Pollutants (NESHAP) -
Air standards for pollutants proposed in December 1991 under the Clean Air
Act Amendments. Promulgated in 1993, NESHAP requirements for the
perchloroethylene drycleaning industry prohibit the sale of new transfer
machines, require retrofitting of existing drycleaning equipment with control
devices and require new machines to be sold with such equipment.
Non-ionic Detergent -
A drycleaning detergent that has no charge.
These detergents carry water by means of solubilization. Non-ionic detergents
are used in charged systems.
Non-volatile Residue (NVR) -
The bulk of the residue left in the
still after the solvent has been distilled out. NVR is made up primarily of
oily, fatty, gummy and insoluble soils removed from clothing.
Oxidizing Bleach - A bleach that utilizes an oxidation process to
decolorize stains or soiled areas. Examples are: sodium perborate, hydrogen
peroxide and sodium hypochlorite.
Percent Detergent -
The ratio of detergent to solvent used in the
drycleaning cycle. Most charged solvents contain a percent
detergent between one half and one and one-half percent, depending on the
drycleaning system being used.
A completely halogenated (chlorinated)
ethene. This chlorinated hydrocarbon has excellent cleaning and degreasing
properties, and is the predominant solvent used in the drycleaning industry.
Also known as Tetrachloroethylene, Tetrachloroethene, Perc
Trade name for
perchloroethylene drycleaning solvent manufactured by ICI.
Per Sec® -
Trade name for
perchloroethylene drycleaning solvent manufactured by Vulcan Chemicals.
Petroleum Drycleaning Solvents -
Drycleaning solvents that are
petroleum based. These are solvents are blends of distillate fractions produced
at petroleum refineries. Most are mixtures of as many as 200 different
compounds and have a variable composition (generally C5 -
C16). Their flash points range from 105° F to
147° F. (New higher
flash point so-called synthetic petroleum solvents are being developed). There
are many names for these solvents including: Stoddard solvent, mineral spirits,
solvent, quick-dry solvent, etc. The earliest petroleum drycleaning solvents
were kerosene, gasoline, benzene and naphtha.
Petroleum Sulfonate -
An early drycleaning detergent (a filter
soap). It is a sulfonate of mixed hydrocarbons of petroleum origin. Petroleum
sulfonates was the original charged-system detergent. Also known as Mahogany
Petroleum solvent dryer (reclaimer) that reclaims
Trade name for one of the more commonly used dry-side
spotting agents. The predominant constituent of Picrin is trichloroethylene.
Polish Filter -
A filter housing that utilizes filter cartridges to filter
fine particles from solvent after the main filter. Mainly used to control redeposition (graying).
Polishing Filter -
A filter used to remove small particles of
carbon or soil that have not been captured by the main filter and can
effectively minimize redeposition of soil on the garments - known as
graying. Polishing filters have pore sizes that are extremely fine
(3 to 5 microns). They are installed downstream of the main filter system.
There are two types of polishing filter mediums - resin-bonded fibers and a
spiral cotton element.
Powder Filtration System -
Drycleaning filtration systems that
utilize filter powder (diatomite) and sometimes filter powder plus activated
carbon as a filtering medium. These systems can be either Constant Pressure
Filters, or Regenerative Filters.
Pre-charged Solvent -
Drycleaning solvent that contains detergent
added by the manufacturer. It has been used largely in coin-operated
Precoat - Filter powder applied to the tube filters or filter
Placing a thin layer of filter powder on the
filtering medium (screen, tube disc) before any impure solvent has passed
through the screen holes. Precoating prevents the clogging of the holes by
providing an immediate layer of filter powder as the first impurities come
- A simple filter housing designed to extend cartridge life by
pre-filtering lint and dirt from solvent by utilizing reusable or
disposable lint bags.
Pump Strainer -
located in front of the solvent pump in a drycleaning machine that prevents
lint and other objects from entering the pump.
Reclamation Efficiency -
A measure of the efficiency of the
reclaiming dryer or drying cycle in extracting solvent from the clothing. Also
known as Drying Efficiency.
A machine used to remove solvent from clothing by
tumbling them in a heated air stream. The solvent vapors are then condensed and
routed to a water separator, where the solvent is separated from the water.
Also known as a Reclaiming Dryer or Recovery Dryer.
Reclaiming Cycle -
The first stage in the drying or reclaiming
process, in which solvent remaining in the garments is vaporized by a stream of
hot air. The vapors are then condensed and the liquid solvent drawn off and
stored for reuse.
Reclaiming or Recovery Dryer -
Recovery Unit -
A process of preparing a solvent for re-use. In drycleaning, this is done by filtering and distilling the drycleaning solvent
after it has removed the soil from the clothes. Solvent can be recycled
repeatedly by a drycleaner.
The return of insoluble soil to the fabrics from
which it was freed during the cleaning cycle. dispersal and redeposition of
insoluble soils is the principal cause of graying.
Reducing Bleach -
A bleach that decolorizes stained or soiled
areas through a reducing reaction. Examples of reducing bleaches are: sodium bisulfite, sodium hydrosulfite and titanium stripper.
Refrigerated Condenser -
A vapor recovery system into which an
air-solvent gas-vapor stream is routed and the solvent is condensed by cooling
the gas-vapor stream. Refrigerated condensers recover solvent emissions by
chilling the air stream below the solvents dew point, causing the solvent
and water vapor to condense. Refrigerated condensers can be placed either in the air stream near the
end of the drying cycle or at the final exhaust point of the process. In
transfer machines equipped with refrigerated condensers, the air stream
received from the washer when the door is opened is typically vented to the
atmosphere after one pass through the condenser. Thirty percent of the solvent
is typically recovered. Vapors from the drying unit are continually routed back
to the dryer after passing through the condenser until the drying cycle ends.
Eighty-five percent of the remaining solvent is typically recovered.
Un-recovered vapors are vented to the atmosphere when the dryer is opened. In vented, dry-to-dry machines equipped with refrigerated condenser,
emissions occur when the door is opened. No-vent or closed-loop machines do not
vent to the atmosphere and have the highest efficiency in recovering emissions.
Also known as a Chiller.
Refrigerated Condenser Coil -
The coil containing the chilled gas
(usually CFC 11 or CFC 12) used to cool and condense the solvent.
Regenerative Filters -
The most widely used type of powder
filtration system. It consists of flexible tubes that are constructed of
braided metal wire, metal helical springs or braided knit fibers. The filter
powder, which is the filter media, is held by the flexible tubes. Spent powder
is removed or bumped and then the regenerated or pre-coated each
day or after each load has been run. Also known as Flexible Tube Filters
or Bump Action Filters.
Rigid Tube Filter -
A type of non-regenerative filter in which
the precoat is supported on an internal wire frame surrounded by a filter
screen. Backwashing is used to remove the filter cake from these filters.
Room Enclosure -
Stationary structure that encloses a transfer
machine system. These enclosures are designed to contain solvent vapors which
are vented to a carbon adsorber or an equivalent control device during
operation on the transfer machine system.
Glycol ether based drycleaning solvent offered as an
alternative to chlorinated solvents and petroleum-based drycleaning solvents.
Rynex reportedly has a flash point of 203° F.
Screen Filters -
Fine mesh screen held in a vertical plane with
nipples that feed into a manifold. Screen Filters are used in powder filtration
systems. The solvent surrounds the screens where the powder collects and
strains insolubles out as the solvent flows through and into the manifold and
out. A variation of this type of filter employs a series of horizontal circular
screens between each of which is a brush which automatically rotates for
cleaning . This filter operates with a blend of sweetener powder and carbon and
is automatic in its dispensing of powders and self cleaning. Very few screen
filters are in use today.
Second Generation Drycleaning Machine -
See Vented Dry-to-Dry
Separator Water -
Wastewater generated from the physical
separation of drycleaning solvent and water in a water separator. Separator
water is a contact water and therefore contains solvent.
A glaze or filler agent used to treat fabrics. Starch is
an example of sizing.
See Still Bottoms.
Sniffer - See Carbon Absorber.
Sodium Bisulfite -
A reducing bleach used in pre-cleaning and
spotting operations. Its main use is in removing the last traces of chlorine
Sodium Hydrosulfite - A reducing bleach used in pre-cleaning and
Sodium Hypochlorite -
The most commonly used oxidizing bleach. It
is normally packaged as a 5% solution but is used in pre-cleaning and spotting
operations in a 1% solution. Sodium Hypochlorite is also widely used in
conventional laundry operations.
Sodium Perborate - A common oxidizing bleach used in pre-cleaning
and spotting operations . It is a highly alkaline substance and is normally
neutralized with acetic acid after application.
SOLVATION Process -
A solvent vapor recovery process in which an
air stream is continuously circulated through the drycleaning machines
condenser, a water bath and the hot clothes in the machines tumbler. When
passing through the water bath, the air stream becomes saturated with water.
The perc and water in the air stream leaving the stream becomes saturated with
water. The perc and water in the air stream leaving the bath form an azeotrope,
which has a lower boiling point than perc alone, thereby increasing the ability
of the machines standard condenser to recover the solvent vapor.
Solvent Mileage -
The amount of fabric cleaned per a quantity of
solvent; a measure of the efficiency of a drycleaning system. Also known as Solvent Consumption.
Solvent Pump -
A pump located in the drycleaning machine that
circulates solvent in the machine.
Solvent Relative Humidity -
The moisture content of drycleaning
solvent with added detergent is expressed as a percentage of the amount of
water carried by the detergent in the solvent compared with the maximum amount
of water which the detergent in the solvent will carry.
Solvent Relative Humidity Instrument
A moisture control device that collects solvent,
air, and moisture vapors from the wash wheel, passes them over a sensing
element that measures solvent relative humidity, and automatically injects
water in the washer when the relative humidity drops below a pre-determined
Total gallons of distilled solvent that must be
replaced to the system for each 100 pounds of fabric cleaned.
Spin Disk Filter - A device containing 36 fifteen-inch diameter
disks of polyester fine mesh material mounted on a hollow central shaft with a
motor drive to spin the shaft. Solvent enters the center housing through the
hollow central shaft. The filter can utilize either filter powder or to be
powderless. Also known as a Centrifugal Disc Filter.
Spot Bleaching -
The use of a bleach in pre-cleaning or spotting
Spotting or Pre-spotting -
The selective application of
chemicals, steam, detergent and/or water to loosen or remove specific stains
from soiled garments. Spotting is sometimes done prior to drycleaning
(pre-spotting or pre-cleaning) but may also be necessary following drycleaning
to remove stubborn stains. Also known as Pre-cleaning.
Spotting Board -
A work surface for pre-cleaning and spotting
work. The spotting board is normally supplied with steam, compressed air and
Spotting Agent -
A chemical used to clean or bleach stained or
heavily soiled areas on clothing. Spotting agents are generally divided into
three classifications: dry-side agents (used to clean non-water soluble stains
or soiled areas), wet-side agents for water soluble stains or soils, and
bleaches which oxidize or reduce stains or soiled areas.
Standard Cartridge Filter -
A cartridge filter (carbon core, all
carbon or carbonless) that has dimensions of 7 5/8 inches by 14 1/4 inches.
Steam Cabinet -
See Drying Cabinet.
Steam Press -
A machine used in the finishing process that
utilizes steam to press clothing after it has been drycleaned. A steam line
from the boiler supplies steam to the press. The garment is held in place on
the press by means of a partial vacuum generated by a vacuum unit. The garment
is pressed by lowering the press on the garment and pressing a foot pedal that
releases the steam. The condensed steam is evacuated by the vacuum unit. See Grid-Head Press and Hot-Head Press.
Steam Stripping -
A method to extract additional solvent from
distillation residues during the distillation process. In this method, steam is
injected directly into the distillation residues in the still. This causes the
boiling point to drop and the distillation rate to increase.
Steam Sweeping -
A technique used during the final stage of
still boil down to recover as much solvent as possible. In this technique, live
steam is swept across the still just above the liquid residue. This results in
a temperature increase and a resulting additional recovery of solvent.
A device used to volatilize and recover solvent from
Still Bottoms -
The waste sludge or solid residue from the still.
Still bottoms contain solvent, water, soils, carbon and other non-volatile
residues. Still bottoms from chlorinated solvent drycleaning operations are
hazardous wastes. Also known as Distillation Bottoms,
Distillation Residues, Still Residues or Sludge.
Still Kettle -
The vessel in which the distillation process
Still Residues -
See Still Bottoms.
Stoddard Solvent -
A petroleum drycleaning solvent which is a
blend of petroleum distillate fractions (C7 - C12). It is
composed of 30 - 50% straight and branched chain alkanes, 30 - 40%
cycloalkanes, and 10 - 20% alkyl aromatic hydrocarbons.
Uneven deposit of non-volatile material on a garment.
Also known as Streaks.
Sweetener Powder -
A type of filter powder that is composed of
activated clay. These clays are adsorptive and will remove soluble impurities
from solvent such as detergents, fatty acids and dyes. This powder has been
used with filter powder to avoid filter clogging.
Temporary Vapor Storage (TVS) -
An emission reduction technology
which provides for efficient, economic recovery and temporary storage of
perchloroethylene vapors using a high capacity polymeric adsorbent.
Tetrachloroethylene or Tetrachloroethene -
See Carbon Tetrachloride.
Third Generation Drycleaning Machine -
A closed-loop (dry-to-dry)
drycleaning machine equipped with a refrigerated condenser.
Titanium Stripper -
A common reducing bleach used on dye stains
and to make whites whiter. The active ingredients are titanous sulfate (10 -
15%) and 1 - 4% sulfuric acid.
Transfer Machine - Drycleaning system in which the washing and
drying operations take place in two separate units. Some transfer operations
have employed three machines: a machine where the clothing is washed; an
extractor, where the solvent is extracted from the clothing by centrifugal
force; and a dryer (tumbler or reclaimer). Also known as a Cold Machine
or a First Generation Drycleaning Machine.
1,1,1-Trichloroethane (TCA) -
A chlorinated solvent that was used
to a limited extent as a drycleaning solvent (particularly in leather cleaning
operations) and was a common dry-side spotting agent. There were problems with
equipment corrosion in TCA drycleaning operations.
Trichloroethylene or Trichloroethene (TCE) -
solvent that has been used as a both a drycleaning solvent and a dry-side
spotting agent. One problem with TCE is that is causes bleeding of many acetate
Tubular Filter -
A cylindrically shaped, fine-mesh screen
supported internally by a coiled wire. These elements are hung vertically from
a manifold inside the filter. Solvent flows inward through the walls of the
elements, then upward. These elements often are coated with a precoat of powder
filter to prevent clogging and maintain proper cake porosity.
A dryer in a transfer operation that vents dryer vapors
to the atmosphere. Also known as Non-recovery Unit or Tumbling
Two Bath System -
A system in which garments are first run
through a solvent/detergent wash cycle and then, to remove residual detergent
and soils, through a relatively pure solvent rinse cycle.
Vacuum Still -
A device that enables drycleaners to distill
petroleum-based solvent safely. In this system, air must be pumped out of the
still to create a 26-28 inch vacuum, permitting petroleum solvents to be
distilled at reduced temperatures (approximately 100° F) and
within safe limits.
Vacuum Unit -
A device that generates a partial vacuum (through
the use of a vacuum pump) for use in steam pressing and spotting and
pre-cleaning operations. The condensed steam from steam pressing operations
(known as vacuum water) is collected in a tank located at the base of the
Vacuum Water -
Wastewater collected through a vacuum line. This
wastewater is generated in pre-cleaning, spotting and steam pressing
operations. It is contact water and is contaminated with solvent and spotting
agents. Vacuum water collected from steam pressing operations is also known as Press Return Water.
A Chlorofluorocarbon drycleaning solvent developed by
DuPont in the 1960s. Also known as 1,1,2-Trichlorotrifluoroethane,
1,1,2-Trichloro-1,2,2-trifluoroethane, Freon 113, Fluorocarbon 113, CFC 113.
Vapor Absorber - See Carbon Absorber.
Vapor Recovery Unit -
A device used to trap solvent vapors. The
vapor recovery unit can recover perc for reuse from vents of a vented
dry-to-dry machine, from a dryer of a transfer machine, or from ventilation
vents in the workplace. See Refrigerated Condenser, Carbon Absorber,
SOLVATION, and Temporary Vapor Storage.
Vapor Absorber -
See Carbon Absorber.
Vented Dry-to-Dry Machine -
A refrigerated condensation unit from
which all the exhaust vapors are vented to the atmosphere when the drycleaning
machine door is opened at the end of the drying cycle. With a vented system,
about 85 percent control of solvent vapors is achieved compared to an
uncontrolled machine. Also known as a Second Generation Drycleaning Machine.
Vented Refrigerated Condenser -
A refrigerated condensation unit
that vents exhaust vapors to the atmosphere from the cylinder when the machine
door is opened at the end of the drying cycle.
Ventless Refrigerated Condenser -
A refrigerated condensation
unit which does not vent vapors to the atmosphere.
Washer (drycleaning) -
A machine used to clean clothing by
immersing and agitating them in solvent.
The heart of the drycleaning machine. It
contains a horizontal, perforated drum or cylinder that rotates within an outer
shell. The shell holds the solvent while rotating drum holds the garment load.
The machine first washes the garments then extracts the solvent by rotating at
high speed. In a hot or dry-to-dry machine, the washer-extractor
also serves as the reclaiming dryer.
Water Separator -
A device that utilizes gravity to physically
separate water that has become mixed with the drycleaning solvent. Water
separators are found on stills, dryers, muck cookers and vapor recovery units.
They prevent the water from returning with the solvent to the solvent storage
Water Soluble Soil -
Soil which dissolves in water. Such
substances include: sugar, starch, gums, salt, flavoring agents and syrups, as
well as a variety of substances found in foods and beverages.
A professional cleaning technique that uses
detergents and water. Specialized machines are used that can be programmed to
control such variables as mechanical action, water drying temperature, moisture
levels in the dryer and water and detergent volume.
Wet-side Spotting Agent -
A pre-cleaning or spotting chemical
used on water soluble stains or soils.
The cylinder rotating drum or tumbler within the
washer-extractor of a drycleaning machine.