【作者】 陈伟；

【导师】 林卫青；

【作者基本信息】 东华大学 ， 环境工程， 2008， 硕士

【摘要】 苏州河经过一、二环境综合整治工程后,河水水质逐步得到好转,河道生态系统逐步得到改善,但是市区段水体溶解氧的含量依然不容乐观,年平均溶解氧含量小于2mg/L。底泥耗氧的作用开始显现出来。为减少底泥耗氧,苏州河三期整治的重要内容之一是底泥疏浚。然而疏浚是否能长期有效地改善苏州河水体溶解氧低的状况,这需要综合考虑沿岸泵站放江对底泥耗氧量的影响。针对苏州河沿岸泵站放江对底泥耗氧量的影响这一问题,研究了底泥耗氧的机理,主要影响因素;以目前国外应用较成功的底泥通量模型为基础,利用实测资料和实验数据进行模型率定和验证,建立了苏州河底泥耗氧量数学模型,模型可以较真实地模拟底泥的耗氧量。有机碳、有机氮的输入是影响底泥耗氧的主要原因。模型模拟结果表明当有机碳、有机氮的浓度都小于3mg/l时,它们对底泥耗氧量的影响基本相当;当有机碳、有机氮的浓度都大于3mg/l后,有机氮对底泥耗氧量的影响相对于有机碳开始明显减弱,底泥耗氧量主要受有机碳浓度的控制。利用模型探讨泵站放江对底泥耗氧的影响,结果表明在目前的放江水平下,平均一次放江后底泥耗氧量增加25.6%～41.5%,放江输入的有机物是苏州河底泥耗氧物质的主要来源,泵站放江是造成苏州河底泥耗氧量增加的主要原因。可以认为,底泥疏浚短期可能会削减底泥耗氧量,但合流污水雨天放江对产生底泥耗氧的影响是长期的。放江量每增减10%,对底泥耗氧量的影响范围在7%～8.5%左右。当放江量较少30%时,底泥耗氧量可减少了25.4%。放江量的减少对底泥耗氧量的影响明显。因此稳定改善苏州河水质,在优化沿岸市政泵站运行的同时,应最大限度地减少泵站向苏州河排放的雨污水量,减少向苏州河输送的污染负荷,做到晴天不排江、雨天少排江。更多还原

【Abstract】 Water quality and aquatic ecosystem in Suzhou Creek have improved gradually since the first and the second comprehensive administration achieved, but dissolved oxygen in water of city area is still low,the annual average content is less than 2mg/l.The influence of sediment consume oxygen begains to appear. In order to reduce sediment oxygen demand,the one of main projects of the third comprehensive administration of Suzhou Creek is sediment dredge. Whether dredging could effectively improve water DO in long time, it need to conside the impact of pumping stations along Suzhou Creek storm water overfall on sediment oxygen demand(SOD).In this dissertation,sediment flux model was used to establish SOD model on Suzhou Creek. The model was calibrated and validated by history materials and experimental data and can relatively succeed to simulate sediment oxygen demand.The main reason of sediment consume oxygen is input of TOC and TON. Using the SOD model simulate, result show that sediment oxygen demand is affected equally by TOC and TON when the concentrations of TOC and TON are less than 3mg/l,sediment oxygen demand is affected mostly by TOC when the concentrations of TOC and TON are more than 3mg/l.The impact of Pumping Stations along Suzhou Creek Storm Water Overfall on SOD was studied using of the SOD model. Result show that SOD increases 26.5 %-41.2% after storm water overfall average one time,which implies that the main reason of SOD increases is storm water overfall of pumping stations along Suzhou Creek,dredging can only remove Suzhou Creek SOD in short term, and combined sewer overflows (CSOs) will build up SOD and lead to low water DO problems in long term. Result show also that SOD changes between 7%-8.5% when CSOs increase or induce 10%,SOD can reduce 25.4% when CSOs reduce 30%,which implies that reduction of CSOs affects SOD obviously. So in order to improve Suzhou Creek qulity, the control on CSOs needs to strengthen.更多还原