Gravity thickener .

for sludge treatment

Stirring and scraping mechanisms are installed in sludge thickener tanks to reduce the water content of sludges and to continously remove the still fluid and pumpable sludge to the central sludge sump. Function The raw, mixed or digested sludge is fed through a central influent cylinder mounted to the thickener mechanism into the thickener tank. The thickening process is intensified with the application of vertically mounted stirring members. By means of an echelon type scraper blade assembly the thickened sludge on the tank bottom is removed to a center hopper from where it is drawn off by hydrostatic pressure or pumped off to further treatment facilities. Depending upon the mode of operation, the supernatant is drawn-off from the surface continously or discontinously into a discharge trough via overflow weirs or via level adjustable or floating supernatant discharge devices.