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CH3041
SEWAGE TREATMENT I
• Sewage = 99.9% H2O  + 0.1% impurities.
Several different methods of S.T. are used depending on the quality of the output effluent that is
required & $$.
• Environmental
Engineers carry
out the design &
improvements to
plant processes.
• QC uses tests
for BOD, TN, TP,
suspended solids and microbiological tests.