PREDICTION OF DISSOLVED-OXYGEN CONCENTRATION ALONG SANITARY SEWERS

The oxygen balance in wastewater collection systems is important in re spect to the degree of biological oxidation that occurs within the str eam and in respect to the control of septicity and its effects. In thi s paper, a simple mathematical model is presented, in order to predict dissolved oxygen concentration profiles along sanitary sewers. The ma thematical model was developed based on an analytical solution of the simple differential equation of dissolved oxygen balance in sewers, an d includes an empirical expression for prediction of dissolved oxygen transfer to the slime layer on the pipe walls. Because the factors con trolling dissolved oxygen balance in sewers are so complex, it would b e unrealistic to expect that with this rather simple model, dissolved oxygen concentrations can be accurately predicted. Nevertheless, it is reasonable to suppose that the predictions may be adequate for some d esign and operation purposes. Copyright (C) 1996 IAWQ.