1 A fraction which is obtained from petroleum
for dry-cleaning
used as an industrial solvent and also dry cleaning
Answers
Working solvent from the washing chamber passes through several filtration steps before it is returned to the washing chamber. The first step is a button trap, which prevents small objects such as lint, fasteners, buttons, and coins from entering the solvent pump.
Over time, a thin layer of filter cake (called muck) accumulates on the lint filter. The muck is removed regularly (commonly once per day) and then processed to recover solvent trapped in the muck. Many machines use "spin disc filters," which remove the muck from the filter by centrifugal force while it is back washed with solvent.
After the lint filter, the solvent passes through an absorptive cartridge filter. This filter is made from activated clays and charcoal and removes fine insoluble soil and non-volatile residues, along with dyes from the solvent. Finally, the solvent passes through a polishing filter, which removes any soil not previously removed. The clean solvent is then returned to the working solvent tank.
To enhance cleaning power, small amounts of detergent (0.5%-1.5%) are added to the working solvent and are essential to its functionality. These detergents help dissolve hydrophilic soils and keep soil from redepositing on garments. Depending on the machine's design, either an anionic or a cationic detergent is used.
Since the solvent recovery is less than 100%, and because dry-cleaning does not remove water-based stains well, entrepreneurs have developed the wet cleaning process, which is, in essence, cold-water washing and air drying, using a computer-controlled washer and dryer. In general, wet cleaning is still being improved and developed, although low-tech versions of it have been used for centuries.
People who make clothes have special symbols to say how they should be cleaned. The international GINETEX laundry symbol for dry cleaning is a circle. It may have a letter P inside to indicate perchloroethylene solvent, or a letter F inside to indicate a hydrocarbon solvent. A bar underneath the circle means that only mild cleaning processes should be used. A crossed-out empty circle means the clothes should not be dry cleaned.
Answer:
Working solvent from the washing chamber passes through several filtration steps before it is returned to the washing chamber. The first step is a button trap, which prevents small objects such as lint, fasteners, buttons, and coins from entering the solvent pump.
Over time, a thin layer of filter cake (called muck) accumulates on the lint filter. The muck is removed regularly (commonly once per day) and then processed to recover solvent trapped in the muck. Many machines use "spin disc filters," which remove the muck from the filter by centrifugal force while it is back washed with solvent.
After the lint filter, the solvent passes through an absorptive cartridge filter. This filter is made from activated clays and charcoal and removes fine insoluble soil and non-volatile residues, along with dyes from the solvent. Finally, the solvent passes through a polishing filter, which removes any soil not previously removed. The clean solvent is then returned to the working solvent tank.
To enhance cleaning power, small amounts of detergent (0.5%-1.5%) are added to the working solvent and are essential to its functionality. These detergents help dissolve hydrophilic soils and keep soil from redepositing on garments. Depending on the machine's design, either an anionic or a cationic detergent is used.
Since the solvent recovery is less than 100%, and because dry-cleaning does not remove water-based stains well, entrepreneurs have developed the wet cleaning process, which is, in essence, cold-water washing and air drying, using a computer-controlled washer and dryer. In general, wet cleaning is still being improved and developed, although low-tech versions of it have been used for centuries.
People who make clothes have special symbols to say how they should be cleaned. The international GINETEX laundry symbol for dry cleaning is a circle. It may have a letter P inside to indicate perchloroethylene solvent, or a letter F inside to indicate a hydrocarbon solvent. A bar underneath the circle means that only mild cleaning processes should be used. A crossed-out empty circle means the clothes should not be dry cleaned.
Explanation: