What is the typical range for Mixed Liquor Suspended Solids (MLSS)?

The typical range for Mixed Liquor Suspended Solids (MLSS) in activated sludge systems is indeed between 1000 mg/L and 5000 mg/L. This concentration is crucial for the effective biological treatment of wastewater, as MLSS represents the quantity of suspended solids present that includes microorganisms which are vital for the biological degradation of organic matter.

Maintaining MLSS within this range ensures optimal conditions for microbial activity, leading to efficient treatment processes. If MLSS levels are too low, it may result in inadequate treatment performance, while levels that are too high can lead to issues such as poor settling characteristics in the clarification phase, which can negatively impact overall process efficiency.