Oxygen Requirements

In activated sludge operations it is necessary to supply oxygen to sustain the process and to provide intimate mixing and contact of activated sludge with the organic matter and nutrients. (A low-speed turbine-type surface aerator is shown in Figure 8.2.14.) Oxygen requirements depend on BOD removal and on process loading. The oxygen requirement is expressed by equation 8.2(1):

lb of oxygen required per lb BOD removed lb mixed liquor volatile suspended solids \

lb BOD applied per day

In equation 8.2(1), "A" is related to the oxygen requirement for synthesis of new cells, and "B" is related to the oxygen requirement for respiration. The value of "A" ranges from 0.35 to 0.55, and "B" ranges from 0.05 to

FIG. 8.2.14 Low-speed surface aerator installation
0 0

Post a comment