Krohne OPTISYS SLM 2100 optical measuring system for sedimentation profile measurement

The Krohne OPTISYS SLM 2100 is an optical measuring system for sedimentation profile measurement and continuous tracking of sludge blanket. It allows for reliable tracking of sedimentation layers in industrial and municipal applications, such as sedimentation basins in power plants, and water plants, as well as sludge blanket measurement in clarifiers and sludge thickeners in sewage treatment plants.

OPTISYS SLM 2100 is the successor of the OPTISENS OAM 2080 sludge blanket measuring system, but has been completely re-engineered to extend its area of application to sedimentation processes. It uses an optical suspended solids sensor, which is submerged into the basin. Unlike ultrasonic-based sludge level meters, the optical measuring principle is not subject to echo returns from walls or separating zones as well as signal damping by fluff or floating sludge.

The SLM 2100 offers three measuring modes: measurement of sedimentation profile, two-zone monitoring and zone-tracking. For sedimentation profile measurement, the system directly measures the suspended solids concentration at all heights as the sensor travels through all layers of the medium. The two-zone monitoring feature enables the monitoring of the heights of two predefined concentrations. It can be used to prevent sludge washout into the next stage.

The SLM 2100 has two 4-20 mA outputs that communicate height and concentration according to the selected measuring mode. Inputs include a rake guard switch that protects the sensor from being caught by the rake. Also maintenance mode and interim measurements can be started remotely via digital inputs.