Simulation Study Of The Effect Of Effluent Of Chenjiashan Gate On Source Water Quality Of Baishizhou Waterworks

With the huge development of society and economy in these decades, water pollution incidents occurred frequently around the world, which seriously affected safety water supply. To further investigate the diffusion and migration of contaminants in the river and the impact of pollutants on downstream water quality, and also to provide a theoretical basis and engineering guidance for the safe operation of waterworks, this study investigated the simulation of pollutant migration and diffusion by three water quality model, i.e. a two-dimensional steady-state mixed-decay mode, computational fluid dynamics and Info Works ICM software water quality model.Firstly, according to the background of water pollution events of Baishazhou Waterworks, three water quality models were established to predict the water quality of downstream by simulation of six conditions, and the maximum relative error between simulative and actual results was 18.72%. This study verified the accuracy of the three models, and proved that the Info Works ICM software water quality model could not simulate process of pollutant diffusion on the transverses.On this basis, the relationship of pollutant concentration of ammonia between the Chenjiashan Gate and source water quality of Baishizhou Waterworks was studied by two-dimensional steady-state mixed-decay mode and computational fluid dynamics, respectively. The results suggested that when the drainage flow was at a maximum value of 29.25 m3/s, the maximum allowable ammonia concentration limits was 6.719 mg/L and 5.8064 mg/L, respectively. The feasibility study of three water quality models in the simulation of Baishazhou Waterworks water quality pollution incidents provided references for the prevention of such water pollution incidents in the future.Moreover, at background of water pollution incidents occurring frequently, this thesis studied the migration and diffusion of ammonia pollution, which was discharged on the shore by the water quality models of Two-dimensional steady-state mixed-decay mode, and Computational Fluid Dynamics model. The results showed that pollutants concentrations decreased rapidly in the front 80 ~ 200 m of river after discharging, while on the transverse, the pollutants gradually approaching background concentrations of pollutants ammonia of 0.23 mg/L after 200 m from shore. The research on the distribution of ammonia concentration of longitudinal and transverse in the river, provided references for the study of reasons for pollution incidents and the prevention of water pollutants event.Finally, it has been concluded that the water quality model of two-dimensional steady-state mixed-decay mode has good accuracy in the prediction of water quality in the straight wide and shallow river by comparing the application of the three models of water quality. Additionally, the water quality model of Info Works ICM software has better convenience, while the Fluent CFD software has better applicability. The comparison results of the three water quality models provided important references for the application of water quality model in other practical engineering.