PURPOSE: To prevent the deteriration of separation capability caused by filter cakes and to effectively use a separating layer continuously for a long time, by providing a fluid separating part through a separating layer provided on the side wall of a spiral flow path.
CONSTITUTION: While raw fluid flowed in from the direction of arrow A, passes through a cylinrical coil-shaped flow path 6, only media pass through a separating layer, which is constituted of a separating membrane 5 and a comparatively rigid filtering material 4, by the pressure difference between the path 6 and a fluid separating part 7. Then the media pass through the separating layer to enter the liquid separating part 7 and flows out from a separated-liquid exit port 10. On the other hand, the concentrated fluid having a decreased proportion of the media flows out in the direction of arrow B. Though the filtered cake starts depositing on the surface of separating layer with the lapse of time, the amount of cake is controlled by keeping the fluid velocity comparatively higher or by changing the velocity and according to the circumstances, the cake is removed.
NAKAMURA MOTOFUMI
ITOU HISASHI
