Agreed with Andrew Fletcher ! ...

Agreed with Andrew Fletcher ! Dear it seems like this system needs operational changes, however much more details and plant survey is required for a complete remedial action plan. Please find below some points and apply them if possible: 1) Increase the RAS (Return Activated Sludge) flow to aeration basin OR biological reactor (If available) to increase the age of bacteria. For example: Increase 10% flow in first step and observe for five days then 15 % to 30% gradually. 2) If any nutrient is dosed i-e DAP or UREA..check the NH4-Nitrogen and PO4 results....they should not exceed more than 1 ppm. Reduce dosing if results are higher than 1 ppm. 3) Coagulant should be dosed at outlet of aeration basin, however rapid mixing is required. If there is a degaser b/w aeration tank and secondary clarifier, dose the coagulant just before degaser for better mixing and retention time. 5) If tertiary clarification is available, dose floculant (Polymer) just before tertiary clarifier @ tertiary upstream. 6) If you have centrifuges or belt press for dewatering, conduct Sludge Volume Index SVI 30 test. Also adjust the dosing of polymer at belt press. 7) Temperature adjustment of effluent is one of the most critical points among treatment. Keep it in consideration. I wish, if I could have the complete data. Best regards.