Modelling of sanitary wastewater composition and operation of a small membrane bioreactor wastewater treatment plant with denitrification and nitrification
(engleski)
The ratio of concentrations of total nitrogen and five-day biochemical oxygen demand in the sanitary wastewater of an energy infrastructure facility in Serbia is many times higher than usual, resulting in only half of the total nitrogen being eliminated in wastewater treatment plants (membrane bioreactor with anoxic and aerobic reactors) by denitrification. The first step of analysis was mathematical modelling of the composition and origins of the input wastewater. The model was developed based on the scientific literature data on composition of human excrement and the data on composition of water used for sanitary purposes. Next, it was successfully verified by comparisons to the experimental data of the wastewater composition. In the next step, a model for wastewater treatment simulation was created by using the BioWin software (Envirosim Associates, USA) in order to examine functioning of the plant and test the effects of several possible modifications of the process. A good agreement with the qualities of the influent and effluent determined by laboratory analyses was achieved after model calibration. The results of simulations showed a tenfold decrease in the total nitrogen concentration and a fortyfold decrease in the total phosphorous concentration in the effluent after introducing the following modifications to the simulated process: ferric chloride dosing, increasing dosing of acetate in the anoxic reactor by a factor of seven, increasing of the waste activated sludge rate by a factor of four and increasing the recirculation flow rate by a factor of three.
(engleski)
Wastewater treatment simulation software; excrement; urine; acetate; nitrogen
(engleski)