Solution：MicroMotion®-N and MicroMotion®-Den were applied to address nitrogen-related issues on site. In addition, tailored retrofit proposals, training materials, and experimental protocols were provided based on operational needs.
Processing Scale：1200m³/d
Treatment Effect：Effluent from the biological treatment system consistently met discharge standards with ammonia nitrogen <15 mg/L and total nitrogen <100 mg/L, while regular on-site service tasks were successfully completed.
Characteristics
(1) Contains nitrobenzene, nitrophenol, aniline, and other pollutants.
(2) High COD, high salinity, and intense color.
(3) Elevated concentrations of inorganic salts such as sodium carbonate and sodium nitrate.
(4) Poor biodegradability with unstable influent quality to the biological treatment system.
(5) High operational complexity and labor intensity, resulting in low process stability.
(6) High organic nitrogen content, making nitrogen removal challenging.
Plant Profile
Description
Our environmental steward service team conducted in-depth communication with the client’s technical personnel and analyzed the operational data, process control parameters, and equipment performance. Through this assessment, the following issues were identified:
(1) Incomplete degradation of ammonia nitrogen;
(2) Unstable denitrification in the Phase I biological treatment unit;
(3) Periodic surges of foaming in the new biological tank;
(4) Incomplete degradation of toxic organics by the iron-carbon + Fenton unit, repeatedly causing shock loads to the biological treatment system.
Option
1. Conducted data analysis & pilot testing, which determined that elevated concentrations of high-ammonia substances (e.g., aniline) were inhibiting nitrifying bacteria activity. Additionally, an insufficient biomass level reduced the system's resilience to shock loads.
2. Pumped low-concentration wastewater into the system to dilute toxic compounds more rapidly through increased recirculation. Non-compliant wastewater within the system was temporarily diverted to an emergency tank for further treatment.
3. Ensured sufficient system alkalinity (alkalinity ≥ 7.14 times the ammonia nitrogen concentration), maintained dissolved oxygen levels above 2 mg/L in the aerobic zone, and kept pH between 8.0 and 8.5.
4. Dosed 200 kg of bio-enhanced nitrifying bacteria to restore and strengthen the nitrification capacity.
Result
The environmental steward service engineers provide on-site instructions to ensure all control and optimization measures were effectively implemented. As a result, the plant achieved 100% compliance with the sewage discharge standards for COD, ammonia nitrogen, total phosphorus, and total nitrogen throughout the year.
The total volume of pollutant discharge was significantly reduced compared to the previous year, ensuring uninterrupted production for all upstream units.
Additionally, under our technical team’s guidance, comprehensive logs and process management protocols were established. The application of scientific, cost-effective, and practical strategies led to notable improvements in quality, efficiency, and cost reduction.
Periodic Service
