Thickening is a procedure used to increase the solids content of sludge by removing a portion of the liquid fraction. Thickening is generally accomplished by physical means, including co-settling, gravity settling, flotation, centrifugation, gravity belt and rotary drum.

A thickener operates pretty much like a settling tank. The feed enters from the middle, are distributed radially, the settled sludge is collected from the underflow, the effluent exits over the weirs. In a continuously operated thickener, there are different zones of concentration. The topmost dear zone is free of solids and comprises the liquid that eventually escapes over the weirs. The next zone is called the feed zone although this zone does not necessarily have the same concentration of feed solids. This zone is characterized by a uniform solids concentration. Below the feed zone is a zone of increasing solids concentration (from feed zone concentration to underflow concentration). This zone is compaction zone.

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PROTEC is a privately owned company established in Doha, Qatar engaged in the fields of Engineering, Supply, Construction, Installation, Commissioning, Operation and Maintenance of various types of equipment for the Water, Waste Water, Energy, and Industrial markets.


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