1. Industrial wastewater shocks
2. Complex composition of influent
3. Low water temperature
Solution：Applied MicroMotion®-N and MicroMotion®-Den to address the collapse of the nitrification-denitrification system caused by industrial wastewater shocks and low temperatures.
Processing Scale：24500m³/d
Treatment Effect：Effluent total nitrogen < 15 mg/L, effluent ammonia nitrogen < 5 mg/L
Characteristics
1. Industrial wastewater shocks
2. Complex composition of influent
3. Low water temperature
Plant Profile
Description
After on-site investigations and data analysis by our technical team, the primary reasons for the increase in ammonia nitrogen levels were identified as follows:
The influent contained industrial wastewater, which caused significant shocks to the system. The shock loads disturbed the nitrification system, preventing it from degrading ammonia nitrogen. As a result, ammonia nitrogen levels in the effluent increased, leading to a rise in total nitrogen (TN) levels.
The water temperature in the biological tank was 12.7°C, and the damaged nitrification system could not self-repair, further hindering total nitrogen removal.
Option
1. Data analysis and bench-scale testing indicated that the increase in ammonia nitrogen levels was due to industrial wastewater shock combined with low temperatures, which suppressed the nitrifying bacteria's activity.
2. Ensured sufficient system alkalinity (alkalinity > 7.14 times the ammonia nitrogen concentration), maintained dissolved oxygen in the aerobic zone above 2 mg/L, and kept pH between 8.0 and 8.5. Ensured dissolved oxygen in the anoxic section was below 0.3 mg/L, with pH between 7.5 and 8.
3. Added 2,000 kg of MicroMotion®-N and 500 kg of MicroMotion®-Den.
4. Suspended excess sludge and increase sludge concentration to promote the growth of nitrifying bacteria, allowing the nitrification system to recover.
Result
After the adjustments, the ammonia nitrogen removal rate was 99%, and the effluent ammonia nitrogen remained stable at below 2 mg/L, well below discharge standards, meeting the discharge requirements.
The total nitrogen removal rate was between 90-93%, with effluent total nitrogen consistently below 10 mg/L, well under the discharge standard of 15 mg/L, ensuring the system returned to normal discharge conditions.
Periodic Service
