Question

How is sludge activated

Answer 1

"Bioreactor and final clarifier. The process involves air or oxygen being introduced into a mixture of screened, and primary treated sewage or industrial wastewater combined with organisms to develop a biological floc which reduces the organic content of the sewage. "

Answer 2

I think u r asking ....activated sludge
1.. in primary treatment -- solid waste like
plastic nd all r removed by sedimentation...now all the solids that settle are called PRIMARY SLUDGE and the liquid part is called PRIMARY EFFLUENT now the pri.effluent is passed in pri. settling tank 4 sec.treatment

2 .SECONDARY TREATMENT ...here the

pri effluents is passed in large aeration tank where they r provided with aerobic microbes called FLOCS which significantly helps in reducing the BOD ..now once the BOD is reduced it is then called SECONDARY EFFLUENT nd passed in sec. settling tank where the FLOCS of bacteria r allowed to settled called "ACTIVATED SLUDGE " nd now this is passed in large anaerobic sludge digestor ....where by the action of anaerobic bacteria gases like Methane , H2S and CO2 are produced ..(BIOGAS) .....nd mow they r released into natural water bodies like river....nd once they r released in environment the anaerobic bacteria does itself due to oxygen environment..........

hope it helps u ......
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