摘要 |
A dry cleaning process in which contaminating solvent vapor is removed from a gas stream discharged from a dry cleaning machine and the stream then recycled. As a preliminary to the removal of the solvent vapor the gas is bubbled through an aqueous liquid. In some gas (for example when the solvent is perchloroethylene) the liquid is water and the gas stream is then returned to the machine where it passes over cooling coils so that the solvent vapor condenses and is collected. In other gas (when the solvent is trichloroethane or trichloroethylene) the aqueous liquid is a solution of a catalyst or emulsifying agent, the solvent being recovered by conventional chemical processes. Removal of the solvent is carried out in a recovery tank having inlet means for the gas extending into the bottom of the tank and including a foraminous screen through which gas is bubbled into the liquid in the tank.
|