Toxicity reduction and recycling system and treatment method for biotreated effluent in printing and dyeing industry

The invention discloses a toxicity reduction and recycling system and a treatment method for biotreated effluent in the printing and dyeing industry, and belongs to the technical field of deep treatment of printing and dyeing wastewater. The system comprises a V-shaped filtering pond, a middle water pond, a magnetic resin reactor, an anaerobic pond, a surface flow wetland and an ecological pond, wherein the magnetic resin reactor is reasonably combined with ecosystems such as the ecological pond and a constructed wetland; the filtering pond is used for removing suspended organic matters in the biotreated effluent by filtering in order to lower turbidity; magnetic resin is used for adsorbing soluble organic pollutants in the biotreated effluent in order to lower chromaticity and biological toxicity. An alternative anaerobic-aerobic process is formed by a pond-wetland-pond combination to further lower the concentration of organic matters, nitrogen, phosphorus and toxic pollutants in a water body in order to for