TECUMSETH
ENVIRONMENTAL
Dewatering and
Water Clarification Expertise
The most common equipment used in municipal wastewater treatment plants for dewatering sludge is a Centrifuge. Other technologies include the Fournier Rotary Press and various types of Screw Presses. The stable delivery of constant solids sludge from a digester is one of the most important factors but other variables are used to attain the desired results at the Centrifuge.

Multivariable control uses all the available inputs to calculate setpoints that will be used to achieve the required results. The inputs include the targets or setpoints (SP) for each control variable (CV) and the measured values (MV) that are available.

In the algorithm, each of these is tested for their influence on each other and the multivariable block is established. The outputs from relationships are used in a Multivariable Predictive Controller (MPC) to determine the output values that regulate the controlled variables.

The entire control is pretested in a simulator to verify the operation, constraints and validity of the model that is created.

Sludge Dewatering to produce high Cake Density is a multivariable challenge. It is no wonder that good operators take time to learn and understand how to manage their processes without the aid of control.

What a Multivariable Control can accomplish is to do what the best operators are capable of doing but they do it from minute to minute, continuously.

Inputs:
- MetsoTS Solids of feed sludge
- Flow of feed sludge
- Polymer Flow
- MetsoLS Solids & Foam of centrate
- Dry Cake Solids (MetsoTS or Lab value)
- Centrifuge Torque (Speed)

Outputs:
- Polymer Flow Setpoint
- Centrifuge Torque (Speed)