Patent ID: 7083715

Claim:
A plant for thickening sludge derived from water treatment comprising at least one wastewater or water treatment unit including a ballasted flocculation zone with floc ballasted with sand or other granular material, a settling zone for separating settled sludge, a recirculating line for circulating settled sludge from the settling zone to a separator that separates the settled sludge into ballast and sludge, a line from the separator to a sludge thickening system for directing sludge from said separator to degassing zone having a minimum surface corresponding to a degassing speed of 100 m/hr relative to the flow rate of said sludge; a thickening system flocculation zone adapted to enable at least one flocculation agent to be mixed with the sludge to be thickened; at least one sludge thickener settler forming a part of a lamellar sludge thickening system and including a lamellar decantation zone including a series of plates, a thickening zone disposed under the plates, an extraction device associated with the thickener settler for extracting thickened sludge, and a clarified water zone above the plates.