| 摘要 |
PURPOSE:To provide the subject system wherein a plurality of filters provided with elastic precision filtration films are connected as seed crystal recovering devices to the circulation path of exhaust brine and arranged so that filtration and inverse cleaning are alternately carried out through change-over valves, whereby adherence of scales to the circulation system is prevented. CONSTITUTION:Exhaust brine containing seed crystals is introduced by opening a change-over valve 24 into a filter 9 having a large number of filtration members formed by extending elastic filtration films on tubular supporters, and the brine not containing filtered seed crystals is exhausted through a valve 28. When a large quantity of seed crystals are adsorbed to the filtration film surface and hence the filtration pressure is increased, a change-over valve 25 is opened to change over to a filter 10 and to exhaust the brine not containing seed crystals through a valve 29. Upon this occasion, when valves 24 and 28 are closed but valves 26 and 30 are opened and an inverse washing pump 11 is operated, the brine not containing seed crystals flows into the filter 9 from the inverse direction and exfoliates and removes seed crystals which have been arrested by the filtration films, the seed crystals being supplied in the circulating brine together with the supplied seawater. |
