MEMBRANE SEPARATION DEVICE

摘要

A membrane separation device (1) comprising: a membrane unit (3) comprising a plurality of membrane modules (2) stacked in the depth direction of a biological reaction tank (10); an air diffusion member (4) arranged below the membrane unit (3) and that diffuses air for membrane cleaning towards the membrane unit (3); and an air bubble group separating member (5) arranged between the membrane unit (3) and the air diffusion member (4) and that causes a group of air bubbles (401) of air supplied from the air diffusion member (4) to be separated into a plurality of air bubble groups (402). The air bubble group separating member (5) has a larger diameter than the diameter of the air diffusion member (4) and comprises a three-dimensional barrier member arranged parallel to the axis of the air diffusion member (4). The bottom of the vertical cross-section of the air bubble group separating member (5) is formed in a downwardly convex three-dimensional shape. The top section of the vertical cross-section of the air bubble group separating member (5) is, for example, a triangular shape whereas the bottom half is a semi-circular shape.