【作者】 尹海龙； 叶之； 徐祖信；

【Author】 YIN Hai-long,YE Zhi,XU Zu-xin (Key Laboratory of Yangtze Aquatic Environment,Ministry of Education,Tongji University.Shanghai,200092.

【机构】 长江水环境教育部重点实验室；

【摘要】 合肥市南淝河是入巢湖的最大支流,也是平时上游无来水水量的缺水河流,水量主要来自于污水处理厂尾水排放及支流污染汇流。本研究开发了模拟水量—污染物迁移转化耦合关系的南淝河水量—水生态数学模型,通过开展水量调度工程试验以及水质监测,对模型进行了率定,模拟论证河流水质改善方案。研究得出:(1)南淝河旱季流速平均0.07m/s,为缓流河流。(2)在上游水源地水库补水量有限的条件下,针对水质COD基本达到Ⅴ类水、NH3-N严重超标的现状,在藻类易于生长的春末及秋初两次调水,提高水流条件,抑制藻类生长;同时不会加重入巢湖污染负荷。(3)调水只能作为应急性措施,改善南淝河水质的根据措施在于削减沿岸污染物排放;即使两个主要污水处理厂达到Ⅳ类水排放标准,河道断面的氨氮仍然无法达到Ⅴ类水质标准;应进一步采取沿岸支流截污等措施。更多还原

【Abstract】 The Nanfei River in Hefei City is the largest river flowing into Caohu Lake.However,it features a water deficient river without upstream inflow at most of the time,while receiving wastewater treatment plant(WWTP) discharge and polluted tributary inflow dominates the river water discharge in dry seasons.In this study,a mathematical model comprising hydrodynamic module and water quality module was developed,and further calibrated with the field data of hydrological and water quality monitoring at 18 stations in dry seasons.The models were applied to simulate the water quality amelioration schemes.The study showed that:(1) Nanfei river is a stagnant river with averaging flowing velocity of 0.07 m/s on the whole;(2) Current chemical oxygen demand(COD) concentration almost reaches the specified water use objective of grade V, however,ammonia concentration is much inferior to the specified water use objective of grade V, inducing algal growth at favorable temperature.So,it is suggested that limited upstream inflow augmentation should be conducted during the late Spring and early Autumn so as to inhibit algal growth by increasing water flowing velocity on the order of 0.20 m/s;(3) The upstream water inflow augmentation can only be conducted as temporary measures;it was found that key measures to ameliorate river water quality lies on abating water pollutants from WWTP and tributaries.However, even the discharged water from WWTPs is improved to gradeⅣ,ammonia concentration will still be inferior to the specified water use.So,measures to abate tributary pollutants should be implemented in the future.更多还原