Question

what is sludge give reason​

Answer 1

Sludge treatment and disposal. ... The hydrolyzed sludge is passed through a flash tank, where a sudden drop in pressure causes cells to burst, and then to anaerobic digestion, where bacteria convert dissolved organic matter to biogas (which can be used to fuel the treatment process).

Answer 2

sludge is

thick, soft, wet mud or a similar viscous mixture of liquid and solid components, especially the product of an industrial or refining process.

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