Experimental Study On The Simplified River Water Quality Model No.1Based On The Turbulent Flow

As a standard of river water quality model (RWQM), the RWQM No.1(RWQM1), which could be directly connected with the standard activated sludge model, has been developed by the international water association (IWA). According to the cardinal selection principles of the sub-RWQM1, on the assumption that the conversion process is merely controlled by the suspension bacterium and has nothing to do with the algae and the plankton, the simplification of RWQM1(the RWQM1Samplified) and the correspongding experiment were conducted in the study.In this test, model flume, river sand, activated sludge and synthetic wastewater are adopted to simulate the common river. The basic situation of the simplified river water quality model No.1can be reflected, and the corresponding experimental conditions can also be satisfied. Through experimental study and model computation examination, some conclusions can be reached as follows:①Under the condition that the initial concentration of CODcr, TN, TP, NH3-N and DO are approximately same, all pollutant indexes in water are decreasing constantly with time. The downtrend is similar, but the descending rate is different. The more the activated sludge is deliverd, the greater the organic pollutant consumption is. Thus the descending rate is getting larger.②In waters of different velocities in the modeling flume, the relationship between descending rate and flow velocity is not simply linear.③Under the certain flow velocities predetermined by the test, the flow velocity is proportional to the amount of DO in water. The larger the velocity is, the stronger the exchange interaction between water and oxygen in the atmosphere is. Therefore, the amount of DO in water is becoming larger.④27kinetic parameters in the simplified river water quality model No.1are analyzed by the sensitivity analysis method. The analysis of parameter sensitivity via the RWQM1Samplified selected the main kinetic parameters of kgro.H.aer.To、khyd.To、βH and βhyd for simulated CODcr, kgro.H.aer.To、kgro.N1.To、βN1、kgro.N2.To、KNO2.N2、βH and βN2for TP and kgro.N1. To and kgro.N1, To for NH3-N, respectively.⑤According to the results of sensitivity analysis, the kgro.H,aer.To is adjusted to2.2d-1the kgro、N1、To is adjusted to0.9d-1,and the khyd.To is adjusted to4.9d-1by several value calculation. Then after the above check and adjustment, it is proved that better simulation results can be obtained by the model.