Textile Cleaning, Drycleaning, Wetcleaning, Stain Removal, Fabric Cleaning

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.

Desorption - Regeneration or stripping of an activated carbon bed, or any other type of vapor adsorber by removal of the adsorbed solvent using hot air, steam or other means.

Detergent - An additive routinely added to solvent to assist in removing water-soluble soils and stains that are not ordinarily soluble in solvent alone.

Detergent Test Kit - Chemical agents used to titrate solvent/detergent mixtures to measure the amount of detergent contained in charged detergent systems. Some of the chemicals used in the kits include: 1,2-dichloroethane, methylene chloride and chloroform.

DF-2000TM – A petroleum drycleaning solvent manufactured by Exxon Chemical. DF-2000™ is a synthetic hydro-treated aliphatic hydrocarbon blend (reported to be predominantly C11 – C12 aliphatic hydrocarbons) that has a flashpoint of 147° F and a specific gravity of 0.77 at 60° F.

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 form 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.

Distillation - 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.

Distillation Bottoms or Distillation Residues - See Still Bottoms.

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 adsorber 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.

Dowclene Ls - Trade name under which 1,1,1-trichloroethane (TCA) was formerly marketed as a drycleaning solvent by Dow Chemical.

Dow-per – Trade name for drycleaning perchloroethylene manufactured by Dow Chemical.

Drop-off Facility – See Dry Drop-off Facility.

Drum - See Cylinder.

Drycleaner’s Secret – A home drycleaning product marketed by Dry Inc. A “sheet” containing the product is placed with the clothing to be cleaned in a conventional dryer.

Drycleaning - The process used to remove soil, greases, paints and other unwanted substances from articles with organic solvents.

Drycleaning Control System - Equipment (e.g. carbon adsorber, 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 the atmosphere.

Dryel – 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.

Dry Drop-off Facility - A commercial retail store that receives from customers clothing and other fabrics for drycleaning at an off-site drycleaning facility and does not clean the clothing or fabrics on site. Also known as Dry Drop-off, Drop-off Facility, or Dry Store.

Dryer - 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 adsorber 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 - Solvents used to pre-clean or “spot clean” non-water soluble stains or soils. Some examples of chemicals that have been utilized as dry-side spotting agents are: perchloroethylene, t richloroethylene, 1,1,1-trichloroethane, carbon tetrachloride, petroleum solvents and amyl acetate.

DrySolvTM – A drycleaning solvent composed of n-propyl bromide (a.k.a. 1-bromopropane). DrySolv is stabilized with nitromethane and 1,2-butylene oxide. DrySolv was first marketed in 2006 by Dry Cleaning TechnologiesTM, a division of Environ Tech International, Inc.

Dry Store - See Dry Drop-off Facility.

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.

Dry Wetcleaning – A relatively new cleaning process whereby clothing is cleaned in a specially designed machine that utilizes a combination of jet air pulsating, tumbling and blotters or felt pads to clean clothing. A detergent (DWX-44) described as a mixture of water and surfactants is also used in the process.

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 discharged.

EcoSolv™ - A petroleum drycleaning solvent manufactured by Chevron Phillips Chemical Company LP. It is reportedly composed of C10 – C13 hydrocarbons and has a flashpoint of 142° - 144° F and a specific gravity of 0.762 at 60° F. EcoSolv was formerly known as HC-DCF High Flash ™.

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.

Equivalent Closed-loop Recovery Systems - A device that volatilizes solvent from the waste stream in a single pass prior to discharge.

Evaporator – 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 solvent concentrations.

Exhaust Damper - A flow control device that prevents the air-solvent vapor stream from exiting the drycleaning machine into a carbon adsorber before room air is drawn into the drycleaning machine.

Extraction - 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.

Extractor - A vertical axis centrifuge which removes most of the drycleaning solvent from the clothing after the “wash” phase is finished.