The system dynamics based research of water quality simulation in the Songhua River water pollution accident

摘要

System dynamics is well suited for studying dynamic nonlinear complex systems. In this paper, system dynamics was applied to rapid-onset water pollution accidents using a one-dimensional water quality simulation model.The on-the-spot monitored data in the Songhua river water pollution accident were used for model parameters calibration and model validation. Dynamic simulations on the processes of convection, dispersion, and degradation (due to chemical reaction and biological absorption) were carried out to (1) characterize the changes in concentration of the typical pollutant nitrobenzene in the river, (2) forecast the changes in pollutant concentration at downstream sections, and (3) adjust the model with different parameter settings. The results show that (1) water quality simulation models can be built with system dynamics quickly and effectively, and (2) such models can provide decision-makers with quantitative information to optimize the forecast of rapid-onset water pollution accidents and the related emergency response measures.