Study on the Water Quality and Quantity Scheduling Scheme in Xinxue River Constructed Wetland of China under the Constraint Condition of Class III of Surface Water Quality

Using Xinxue River Constructed Wetland as the study object, the wetland prediction models based on BP neural network were established through the seasonal division of the wetland, and the maximum influent water load was determined on the constraint condition that effluent water quality achieved class III of surface water quality. Then nonlinear functions of water quality and quantity scheduling were constructed by Origin software. The optimal influent load was determined adopting prediction results of the models as constraint conditions of the functions. Thus the water quality and quantity scheduling scheme of the wetland was established. The results show that optimal influent load for Feb. similar to May: the influent water quantity is no more than 8560m(3)/d, CODCr is 25.47mg/l similar to 26.37mg/l, ammonia nitrogen 0.11mg/l similar to 1.0mg/l, TN 10.28mg/l similar to 10.51mg/l, TP 0.16mg/l; for Jun. similar to Sept.: the water quantity is no more than 31750m(3)/d, CODCr is 26mg/l similar to 32.36mg/l, or 37.15mg/l similar to 45.37mg/l, ammonia nitrogen 0.48 mg/l similar to 1.78mg/l, TN 5.15mg/l similar to 6.18mg/l, TP 0.07mg/l similar to 0.09mg/l; for Oct. similar to Dec.: the water quantity is no more than 11070m(3)/d, CODCr is 24.55mg/l similar to 26.91mg/l, ammonia nitrogen no more than 0.75, TN no more than 8.61 mg/l, TP 0.10mg/l similar to 0.12mg/l, or 0.16mg/l similar to 0.17mg/l.