Dry solids DS dewatering

Obtaining extra-dry cake using a decanter (DS operation) is a relatively new technique for the decanter, having been developed only since approximately 

Whereas, hitherto, dewatering a digested sewage sludge would have produced a cake with, at best, 18-20% solids, today well over 30% is possible. 

When operating properly in DS mode, a decanter will be virtually full of cake, from end to end, and from bowl wall to pond surface. The conveyor will be pushing the cake towards the discharge ports against a restriction, a baffle or a narrowing of the conveyor pitch, or against the nip between conveyor hub and the beach. 

Finally, for DS work a correlation is needed for cake dryness and centrifuge capacity. This is done by graphing cake dryness against the function feed rate/ g-volume. A line is then drawn through the points of maximum dryness. This line then defines the threshold between clean and dirty centrate. To enable 

FUim e 6. 39. Graph - Cake Dryness v Feed Rate/g-Volume - DS. 

---