Biological water treatment process and plant using activated sludge process to control aeration

摘要

The procedure in which water is passed through a biological tank with a free or mixed biomass and alternating oxidizing and reducing periods, subjecting the mixed liquor to a sludge and water separating phase, includes preliminary stages in which minimum (T1min, T2min) and maximum (T1max, T2max) authorized aeration and non-aeration times for the liquor are fixed. The procedure in which water is passed through a biological tank with a free or mixed biomass and alternating oxidizing and reducing periods, subjecting the mixed liquor to a sludge and water separating phase, includes preliminary stages in which minimum (T1min, T2min) and maximum (T1max, T2max) authorized aeration and non-aeration times for the liquor are fixed. The preliminary stages also include fixing lower (SB NO3) and upper (SH NO3) values for the concentration of nitrates in the treated water or mixed liquor, and fixing at least one upper value for the oxidation/reduction potential (SH redox) of the mixed liquor.