Method of bacteriostasis or disinfection for permselective membrane

摘要

In the invention, the pipe lines around permselective membranes and the surfaces of permselective membranes are intermittently disinfected by adding an inexpensive acid such as sulfuric acid or the like to pre-treated crude water so as to make the water have a pH of 4 or lower. The treatment is effected intermittently at intervals of from 1 day to 1 week, and the time for the treatment falls between 0.5 and 2.5 hours. Accordingly, the invention provides a method of surely disinfecting the permselective membranes in membrane separation systems.