Abstract: An integrated device and method for enrichment, purification and separation of microplastics in a secondary effluent are provided. This integrated device comprises a micro-spray system and a filtering system with multi-stage filtering units, and marked screen meshes were installed in each filtering unit. The microplastics in secondary effluent are enriched on the surface of the marked screen meshes through the retaining effect. Then, lower concentration of alkali, acid or oxidant combined with the heat treatment to weaken the interaction forces between the inorganic/organic foulants and the enriched microplastic. On this basis, the micro-spray system was used to rinse the multistage filtration system, which generated shear force to carry away the foulants on the surfaces of the enriched microplastics, thereby achieving the purification and separation of microplastics synchronously. These are performed in the marked screen meshes, in which the microplastic are not subject to any path transfer or loss.

Abstract: A method for constructing a dynamic-like membrane to control membrane fouling of MBR includes: determining a critical pore size of a base material according to an average size of activated sludge in a membrane tank. The base material is detachably fixed on the outer layer of a conventional MBR module, which is placed into the membrane tank of a wastewater treatment system. Then the aeration rate of a membrane area in the MBR module is reduced. With the assistance of the driving pressure of the MBR module itself and the physical interception of the base material, the inherent activated sludge in the membrane tank is used to form a dynamic-like membrane on the surface of the base material.