Treating hot aq. degreasing liq. for reuse

摘要

In the purificn., recovery and reuse of hot aq. degreasing baths nd spray cleaners by ultrafiltration at below the cloud point of the process medium. The novelty is that the process medium temp. is reduced before ultrafiltration and opt. the cloud point is increased using chemical additives and/or the degreasing cleaner formulation compsn. is selected so that the process medium cloud point is above the temp. at which ultrafiltration is carried out. Appts. for carrying out the process includes a heat pump or a countercurrent cooling system for the process medium.