Respirometric assessment of storage yield for different substrates

A new procedure has been defined for the respirometric assessment of bacterial storage yield as defined in the Activated Sludge Model No.3. The procedure was used to determine the storage yield, Y-STO, associated with acetate, glucose and domestic sewage, together with mixtures of acetate/glucose and acetate/domestic sewage at different initial F/M ratios. Y-STO was calculated as 0.78 gCOD(gCOD)(-1) for acetate, 0.87 gCOD(gCOD)(-1) for glucose and 0.96 gCOD(gCOD)(-1) for domestic sewage. The Y-STO of substrate mixtures was found to reflect the characteristics of the dominant fraction in the mixture.