An external mbr sewage treatment system

Abstract

The invention relates to a sewage treatment system with an external MBR (Membrane Bioreactor). The sewage treatment system with the external MBR comprises a bioreactor and a membrane separation unit, wherein a sludge separation device is arranged between the bioreactor and the membrane separation unit; a first pipeline which is used for delivering mixed liquor in the bioreactor to the sludge separation device and a second pipeline which is used for refluxing sludge separated out in the sludge separation device to the bioreactor are arranged between the sludge separation device and the bioreactor; and a third pipeline which is used for delivering mixed liquor separated through the sludge separation device to the membrane separation unit and a fourth pipeline which is used for refluxing mixed liquor in the membrane separation unit to the sludge separation device are arranged between the sludge separation device and the membrane separation unit. According to the sewage treatment system with the external MBR, through decreasing the concentration of sludge entering the membrane separation unit, the quantity of reflux of the mixed liquor of the sewage treatment system with the external MBR is further decreased; the treatment effect of the whole system is improved; and running and construction costs are deceased.

Description

technical field [0001] The invention relates to the field of sewage treatment, in particular to an external MBR sewage treatment system. Background technique [0002] Membrane Bioreactor (Membrane Bioreactor, referred to as MBR) technology is a new process combining biological treatment technology and membrane separation technology. The membrane separation unit is used to replace the secondary sedimentation tank in the traditional process, and the solid-liquid separation is carried out efficiently, and the obtained The stable reclaimed water used directly enables the sewage to be recycled. [0003] According to the layout of the membrane separation unit, MBR can be divided into two categories: built-in type and external type. Among them, the external MBR is widely used in the fields of large-scale sewage treatment and reuse and industrial wastewater treatment. [0004] However, in the actual operation process, it is found that in order to ensure the flux of the membrane ma...

AI Technical Summary

Problems solved by technology

[0010] Excessive reflux of the mixed liquid will lead to changes in the push flow state of the bioreactor, and the pollutants will flow out of the reactor if they are not completely degraded, making the effluent water quality worse

[0011] 2. The energy consumption of the sludge circulation system is high

[0012] Excessive mixed liquid circulation flow will increase the power consumption of the reflux system, thereby increasing the operating cost of the entire treatment system

[0013] 3. Increased construction investment

[0014] If the cross-flow filtration is satisfied and the reactor works in a push-flow state, the volume of the reactor will be very large, so the construction cost will be greatly increased

Images