Modeling the yield of activated sludge in the presence of 2,4-dinitrophenol

In this work, a model was developed to evaluate the yield of activated sludge in the presence of 2,4-dinitrophenol (dNP). Experimental results show that the presence of dNP substantially reduced the sludge yield at all solid retention times tested, but that it had no negative effect on the bioactivity and settleability of activated sludge. With the established model, the maximum observed sludge yield (Y′max)(Y′max) and specific endogenous respiration rate (kd) for the sludge without dNP dose were estimated as 0.79 g-MLSS/g-COD and 0.042 d−1, respectively, whereas for the sludge dosed with dNP the corresponding values were calculated as 0.56 g-MLSS/g-COD and 0.056 d−1, respectively. In the presence of dNP at 5 mg/l, the energy uncoupling coefficient was calculated as 0.29.