Application of the technology of water lifting and aeration on improving water quality in a Deep Canyon Reservoir - a case study from northern China

摘要

The technology of water-lifting and aeration can be widely applied in water aeration, algal inhibition, and endogenous pollution control. The Jin-Pen reservoir has been undergoing increasing water pollution in the past few years. To solve this problem, the water-lifting aerator system was installed here in the summer of 2010, and its improving effect on water quality was investigated. The results showed that under the mixing and aeration conditions, the thermal stratification structure was disturbed but not destroyed. The vertical water temperature difference was reduced by 3-5 ℃, and the surface temperature fell at 2.1-3.6 ℃. The seasonal aerobic state was withheld at the bottom of the reservoir, and the concentration of DO was maintained above 2 mg/L at the sediment surface. The decay rate of DO in the hypolimnion decreased by 51.2 and 49.6%, respectively, compared to the same period in 2008 and 2009. The concentrations of TP and NH_3-N in the overlying water on the sediment surface decreased to 0.12 and 0.25 mg/L, respectively. The algal abundance in the surface water was reduced by more than 75-80%. However, the present cost of water improvement considering the current water supply capacity (80 × 10~4 m~3) was only 0.004 Yuan RMB/m~3.