Definition and Areas of Use :
When pumping excess active sludge from the sedimentation tank to filter presses or belt presses, cationic polyelectrolyte is added to the sludge line to dewater the sludge.
Cationic polyelectrolyte is widely used in sludge dewatering units of wastewater treatment plants.
In processes where sludge dewatering is performed with centrifuge decanter, belt press or filter press, the flocculant that is mixed with the help of a static mixer is dosed to the pressurized sludge line.
The working principle of the cationic polyelectrolyte product is generally based on ion exchange between the electrical charges of the suspended solid particles and the polymer chain in the aqueous solution. The stable structures of the solid particles are disrupted and this leads to coagulation or flocculation.
Cationic polyelectrolytes are diluted between 0.05% and 0.1%. The preparation solution is generally prepared as 0.5% by adding the original product to water during mixing. Since the characteristics of the sludge to be dewatered are different, the dosages to be applied are determined as a result of jar tests and operational trials in a laboratory environment.