Caprolactam wastewater treatment system and method

The invention discloses a caprolactam wastewater treatment system and a method thereof.The caprolactam wastewater treatment system comprises a first regulating tank and a second regulating tank, and the first regulating tank and the second regulating tank are connected to a mixing tank together after passing through a struvite crystallization device; the mixing tank is sequentially connected with a biological selection tank, a hydrolytic acidification phosphorus release tank, an anaerobic denitrification composite tank, an aerobic multiplication composite tank, a baffled sedimentation tank, an efficient coagulative sedimentation tank and an intermediate water tank; the baffled sedimentation tank is connected with the biological selection tank through a sludge return pipe, and the baffled sedimentation tank and the efficient coagulative sedimentation tank are connected with the sludge concentration tank; and the aerobic multiplication composite tank is connected with the anaerobic denitrification composite tan