OPERATION OF MEMBRANE SEPARATION APPARATUS

PURPOSE:To operate a cross flow type membrane separation apparatus so as to continuously obtain a high filtering efficiency. CONSTITUTION:For example, a filter 10 has a cylindrical double structure and the interior thereof is partitioned into two chambers by a ceramic filter 12. One end part of one chamber 14 is connected to a raw soln. tank 20 through a circulating passage 18 equipped with a circulating pump 16 and the other end part thereof is connected to the raw soln. tank 20 through a circulating passage 22. The other chamber 24 of the filter 10 is connected to a filtrate tank 30 through a filtrate passage 28 equipped with a filtrate outlet valve 26 at the end part on the side of the circulating passage 22. In this membrane separation apparatus, the filtrate outlet valve 26 is closed a specific time after the circulating pump 16 is stopped during filtering and, thereafter, the circulating pump 16 is again operated for a specific time and once stopped to open the filtrate outlet valve 26 and, thereafter, the operation of the circulating pump 16 is again started to again perform filtering.