Dry cleaners use a process called "dry cleaning" to remove stains and dirt from garments without using water. Dry cleaning is particularly suitable for delicate fabrics or garments that might be damaged if washed with water. The chemical solvent most commonly used in dry cleaning is called perchloroethylene (also known as "perc" or "PCE"). While there are some alternative solvents, perc is still widely used in the industry.
Here's how the dry cleaning process works and how the chemical solvent is removed after washing:
Pre-treatment: Before the actual dry cleaning process begins, dry cleaners may pre-treat specific stains or heavily soiled areas with a special solvent or detergent to loosen and break down the stains.
Cleaning in the dry cleaning machine: The garments are loaded into a large, drum-like machine specially designed for dry cleaning. The machine is then sealed, and the cleaning solvent (usually perchloroethylene) is added to the drum. The garments are agitated and tumbled in the solvent, which helps to dissolve and remove the dirt and stains.
Filtration and distillation: After the cleaning cycle, the solvent, along with the dissolved dirt and stains, is filtered to remove any debris or particles. The filtered solvent is then distilled to remove the contaminants and separate any water or impurities that may have been absorbed during the cleaning process.
Reuse or disposal: The purified solvent is then reused for future cleaning cycles if it meets the required standards. However, over time, the solvent can degrade or become less effective, so it may need to be disposed of, and fresh solvent added to the system.
Drying: Once the garments are cleaned and the solvent has been removed, the machine enters a drying cycle. Warm air is circulated in the drum to evaporate any remaining solvent from the garments.
Post-spotting and finishing: After the drying cycle, dry cleaners may perform additional spot-treatment if needed, and then the garments are pressed or steamed to give them a finished look before they are ready for pickup.
It's important to note that dry cleaning facilities have specialized equipment and safety measures to handle the chemicals properly. Perchloroethylene is classified as a hazardous substance, so proper disposal and handling are crucial to protect the environment and workers' health. Dry cleaners must comply with regulations to ensure the safe use and disposal of these solvents. Some modern dry cleaning establishments have adopted more environmentally friendly solvents and technologies to reduce their impact on the environment and human health.