What is Mixed Liquor Suspended Solids? (MLSS)

Mixed Liquor Suspended Solids (MLSS) refers to the concentration of suspended solids in the mixed liquor of an activated sludge wastewater treatment process.

It includes a mixture of microorganisms (such as bacteria), organics and inorganic suspended solids. MLSS is a critical parameter used to monitor and control the biological treatment process's performance. By measuring MLSS levels, operators can assess the biomass concentration, determine the treatment efficiency and make adjustments to ensure optimal degradation of organic matter and removal of pollutants from wastewater.

Maintaining appropriate MLSS levels is essential for achieving effective treatment and meeting regulatory discharge standards in wastewater treatment plants.

MLSS and TSS Probe

Why Measure TSS and MLSS?

Measuring Total Suspended Solids (TSS) and Mixed Liquor Suspended Solids (MLSS) is essential for various environmental and industrial applications. TSS monitoring offers insights into water quality, in pollution detection and the assessment of aquatic ecosystem health.

MLSS measurement is crucial for optimizing wastewater treatment processes, ensuring effluent meets regulatory standards without harming receiving water bodies. By accurately measuring TSS and MLSS, operators can optimize treatment efficiency, conserve resources, protect the environment, and comply with regulations, thus promoting sustainable water management practices and safeguarding public health.

Data Sheet


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Photonic Measurements is:
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