A pharmaceutical enterprise in Zhejiang adopts ECM compound bacteria enhanced biological aerated filter process（ECM-BAF） to carry out advanced treatment of the original wastewater after biochemical treatment. Instead of the advanced treatment technology of removing the ammonia nitrogen from the sewage station by the original broken point and chlorine method

it can solve the disadvantages of the pungent odor pollution

serious pipeline corrosion and high running cost existing in the broken point chlorination method. The operation results show that the ECM-BAF process for advanced treatment of wastewater can achieve the desired results

the concentration of effluent COD can basically meet the removal rate of higher than 55% or the concentration of COD<300 mg/L

the removal efficiency of ammonia is also relatively stable

can meet the effluent ammonia concentration is less than or equal to 10 mg/L requirements.