Polycarbonate process wastewater treatment method

The invention discloses a polycarbonate process wastewater treatment method using a two-stage countercurrent continuous extraction system. The two-stage countercurrent continuous extraction system comprises a mixing kettle, a peristaltic pump, a centrifuge, an evaporator, a mixing kettle, a wastewater storage pot and a resin adsorption tower. A solvent used for synthesizing polycarbonate is used as an extractant, a feeding volume ratio of the extractant to wastewater is 0.08-0.1:1, and a feeding mass-to-volume ratio of resin to wastewater is 0.025:1. The resin used for adsorption is polystyrene resin. The method has the advantages of recycling of phenol substances in wastewater, less consumption of the extractant, low wastewater treatment cost and easy industrial amplification. The recovered phenol substances can be used for synthesizing polycarbonate, and treated brine can be directly discharged, or can be discharged to high salt environment, or can be used for the preparation of sodium hydroxide, chlorine a