Sometimes, urban domestic sewage treatment plants may experience the inorganic transformation of activated sludge due to pipeline faults or process abnormalities. As this phenomenon becomes increasingly severe, it can greatly reduce the adsorption and degradation capacity of activated sludge for pollutants, directly affecting the effluent standards. So, how can we quickly and accurately determine the "inorganic transformation of activated sludge"? Let me share a case with you: Table 1: Carrousel oxidation ditch process. After testing the sludge in the biological tank, it was found that MLSS: 4100mg/l MLVSS: 920-1200 mg/l SV30:20%, SVI=49 MLVSS/MLSS=22%. On site testing of the sedimentation of activated sludge in the oxidation ditch showed that sludge water separation was basically completed in 2 minutes.
Table analysis: The volatile components of activated sludge are relatively low, with inorganic components accounting for about 70%. The degradation efficiency of various indicators in the activated sludge system is low, and the impact resistance is weak. It is prone to sludge leakage in the face of instantaneous water volume impact and system collapse in the face of instantaneous water quality abnormal impact.
Suggestion: Reasonably optimize sludge discharge, with MLVSS greater than 2000mg/l (production should be arranged based on inflow indicators, water volume, desilting machine output, mud cake moisture content, and other indicators), to avoid high water load impact caused by unreasonable use of lift pumps, and to avoid blind sludge discharge leading to loss of effective components in sludge and exceeding effluent standards.
Summary:
Characteristics of inorganic sludge: 1. Light color; 2. Good settlement; 3. Low MLVSS (reference value below 2000) and low MLVSS/MLSS (reference value below 40%); 4. SVI is relatively low (reference value below 60).
