[Visitor (223.167.*.*)]answers [Chinese ] | Time :2021-04-24 | The sludge index reflects the looseness and cohesion and settlement performance of the active sludge. The low sludge index indicates that the mud grain is small, tight, inorganic, lack of activity and adsorption ability, and the index is too high, indicating that the sludge will expand, or has expanded, the sludge is not easy to precipitate, affecting the treatment effect of sewage. For the general urban sewage, under normal circumstances, the sludge index is generally controlled at 50- 150 is appropriate. For wastewater with high organic content, the sludge index may be much higher than the above value. SVI: Sludge volume index is a measure of the performance of active sludge sedimentation. Refers to the aeration tank mixture after 30min quiet, the corresponding 1g dry sludge occupied by the volume (in mL), that is: SVI - mixed liquid 30min quiet after the sludge volume (mL) / sludge dry weight (g), that is, SVI -SV30/MLSS. SVI value can better reflect the loose degree of activated sludge and condensation settlement performance. Good active sludge SVI is often between 50 and 200, SVI value is too low, indicating that sludge activity is not enough, may be caused by the lack of nutrients in the water body. SVI too high sludge, indicating that sludge expansion may occur, by stopping the aeration, so that sludge subsidence hypoxic anaerobic nitrification can play a very good role. If due to overbreeding of filaments, the corresponding disinfectant should be added, if necessary, to drain the aerobic pool to re-cultivate aerobic sludge... |
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