1.1. Key Pollutants:
Phenylcyanide and Thiocyanate
1.2 Key Characteristics
① High toxicity
②High COD
③High total nitrogen
④High ammonia nitrogen
Solution：Applied MicroMotion®-N,to address the collapse of the nitrification system caused by high concentrations of phenyl cyanide and thiocyanate in the influent.
Processing Scale：1100m³/d
Treatment Effect：Ammonia nitrogen in the effluent from the biological tank was reduced to below 50mg/L
Characteristics
Phenylcyanide and Thiocyanate
① High toxicity
②High COD
③High total nitrogen
④High ammonia nitrogen
Plant Profile
Description
The effluent ammonia nitrogen consistently failed to meet discharge standards.
Option
1. Conducted data analysis and confirmed that elevated concentrations of toxic substances (e.g., phenyl cyanide, thiocyanate) were inhibiting nitrifying bacterial activity.
2. Supplemented with liquid alkali and sodium carbonate to ensure sufficient system alkalinity (alkalinity > 7.14 times the ammonia nitrogen level), maintained dissolved oxygen > 2 mg/L in the aerobic zone, and kept pH between 8.0–8.5.
3. Dosed 800 kg of MicroMotion®-N, to improve nitrification capacity.
Result
Following the adjustments, the ammonia nitrogen removal rate reached 99%, with effluent ammonia nitrogen consistently maintained below 1 mg/L, which was well below the discharge standard of 10 mg/L. The system successfully met compliance requirements and returned to stable operation.
Periodic Service
