Photochemical recovery - using membrane filter for high flow rates and low concns. and second membrane with low flow at high concn. with return of retained matter to collection tank

摘要

To separate dissolved matter in a liq., for recovery and further use of the matter, and/or liquid, the soiled liq. is passed through an initial membrane filter (6) designed to take high volumes with low. concns. of dissolved matter. Matter retained by the membrane filter is returned to the liq. supply so that its concn. is successively increased. Conc. liq. is passed through a second filter membrane (7), which is structured to take small volumes with a high concn. of matter. USE/ADVANTAGE - Partic. for waste water from photographic processing baths, to recover the dissolved photo chemicals. Operation gives an effective sepn. of fine dissolved matter to give clean water and recovered chemicals which can both be used again.