A membrane bioreactor system which is adapted of a backward gravity flow system

摘要

Provided is a backward natural flow type membrane bioreactor system (MBR system), in which raw water treated in an aerobic tank (300) is discharged to a membrane separation tank (500) by the power of a pump (P3) and treated water other than the treated water stored in the membrane separation tank (500) is conveyed to the aerobic tank (300) as conveying sludge by a natural flow type. According to the present invention, the initial installation cost and the operating cost are significantly reduced, the DO in the aerobic tank (300) can be accurately controlled only by the pump power or the operation time control, a very compact MBR system can be constructed, and the need for stopping the MBR system is reduced to increase the processing efficiency.