Temperature affects the performance of activated sludge
systems as a result of its impact on the rates of biological reactions.
According to Leslie Grady et al. (1999), optimum temperatures for
bacterial activity are in the range of 25e35 C. Fig. 2b shows that
the variation of temperature between 26 and 30 C did not exert
any notable effect on COD, BOD and TSS removal. This result is in
agreement with Morgan-Sagastume and Allen (2003) which
showed that the mesophilic temperature shift from 30 to 35 C did
not produce any significant effect on the SCOD removals and SVI.