Simulation And Applications Of Water Quality Model In Jinwei Lake In Baoji

On the base of intensive literature survey and data taken from Wei-He River in the city of Baoji called Jinwei Lake, the models of COD, NH₄⁺-N and P were established during the analysis of large amounts monitored data. The parameters of the models were determined by CFD software. These models were used for reckoning the water quality. Conclusions were made as follows.(1) PH,COD_Mn,NH₄⁺-N and P in Jinwei Lake varied from 6.61 to 8.8,3.18 mg/L to 10.98mg/L, 0.275 mg/L to 2.28mg/L and 0 mg/L to 0.12 mg/L, which showed that the extent of variation is wide because of flux and shut-down time.(2)The models and parameters of water quality were verified. The results showed that the average error of COD, NH₄⁺-N and P were 8.8%, 8.3% and 36.6%.The forecasted concentration of NH₄⁺-N and COD in lake shows that the error was less than±10% . Because of the concentration of P was low, and the transformation iscomplicated; the error of P has a great difference between the forecasted and the fact, but the error was also less than 50%.(3)Water quality was affected by flux and shut-down time. Based on the factual complexion of Jinwei Lake, if we want to keep the water quality of lake to the allowed standard (《Environment Quality Standard of Surface Water (GB3838-2002)》), when flux from upriver reservoir was about 0.1m³/s, the suggested period of sluice were about 36 days.