【作者】 陈玲；

【导师】 刘德启；

【作者基本信息】 苏州大学 ， 分析化学， 2009， 硕士

【摘要】 随着我国经济与人口的快速增加,污水排放总量也在迅速增加,为遏制其造成的生态环境污染,近年来,我国加大了城市污水与工业废水的集中处理率。排放自然水体是污水的自然归宿,也是目前我国污水最主要的出路。对于已建成的污水处理厂,其纳污水体也就是一定的。自然水体对接纳废水具有一定的稀释与净化能力,但这个稀释与净化能力是一定的。随着污水排放量的增加,会加剧废水对纳污水体带来冲击和负面影响。而且对于作为纳污水体的河流,在修复过程中,其接纳废水量必然会对修复植物的生长产生影响。因此,研究污水处理厂的废水排放量对受纳水体本身和其修复植物的影响,对水环境的保护和水体修复,具有重要的理论与实际意义。本文通过对自然水体、废水排放量等条件的模拟,通过大量实验,取得以下重要结论:污水处理厂外排水对受纳水体中的有机物有明显的影响。实验结果表明,水中有机物与叶绿素都随接纳水量而增加,COD除3#比对照低32%外,2、4和5#中COD分别比对照高93%、46%和46%,叶绿素除3#比对照低51.7%外,2、4和5#中叶绿素分别比对照高129.9%、106.5%和81.8%。这说明排水促进了水体藻类初级生产者的演替过程;也说明浮游植物是水体COD的主要贡献者。外排水对受纳水体氮磷也有显著的影响。总氮随接纳水量的增加而显著增加,与总氮相比,而水中总磷与接纳废水量的关系并不显著。按照湖泊N、P限制性因素的Redfield比值判断,对照体系1#的氮磷相对平衡,而接纳水量最少的2#系统N起限制作用,随着接纳水量的进一步增加,磷则成为主要的限制性因素。外排水对受纳水体溶解性无机盐的积累贡献明显。污水处理厂达标外排废水能显著地增加受纳水体的溶解性盐,可能会导致水生生态系统的退化或增加水体修复的难度,这在干旱地区的水体可能会更加明显。外排水对受纳水体底泥有机质的影响也十分显著,接纳水中的有机物水体中有机物的沉降与积聚,反而促进了底泥中有机物的矿质化过程。在用修复植物修复已退化的水体时,作为污水处理厂尾水的受纳水体,采用伊乐藻作为修复植物,可以取得比采用水网藻作为修复植物更好的修复效果。一定量的尾水会对植物的生长环境产生某种胁迫作用,而伊乐藻对这种胁迫的抵抗能力较强,在胁迫条件下,也可以较好的生存。在设计污水处理厂及选址时,最好能将污水处理厂废水的排放量与受纳水体水量的比例控制在1:100以下。在该比例条件下,尾水对受纳水体及其修复植物影响较小,可将纳污水体的COD、TN、TP控制在一个相对较低的水平上,且修复植物受到的环境胁迫也较少,能够很好的生长。更多还原

【Abstract】 As China’s economy and the population rapid increased, the effluent is also increase greatly. In order to curb it ecological and environmental pollution, our country has increased the rate of the city sewage and industrial wastewater treatment in recent years. Emissions to natural water are the natural destination of effluent, and it is the most important way in our country.To the sewage treatment plant which have been completed, and its receiving waters are definite. Natural waters have the ability to dilution and purification the wastewater what it accepted, but this capacity is limited. With the effluents increased, it will aggravate the effluent to receiving water. And it also have impact on the repair process, the effluent may have an impact on the growth of plants. Therefore, Study on the effect of effluent met the standard from Sewage Treatment Plant on the receiving waters and subsequent repair plant, which has important theoretical and practical significance.This article analyzes factors like natural water, the amount of effluent and et, we obtained following important conclusion:The effect of effluent on organic matter content of the receiving water was very significant. The results show that organic matter and chlorophylls in the water increases along with the accept water. Compared with the control system, the COD of the 3# system lowed 32%, 2 #、4 #、5 # system COD increased 93% ,46% and 46% ; The chlorophylls of 3# system lowed 51.7%,2 #、4 # and 5 # system chlorophylls increased 129.9%、106.5% and 81.8%; It means that the effluent accelerate the succession of primary producers; this also shows that the algae are the main components to COD.With the effluent increasing, the total nitrogen in the water increased greatly, but the significant correlation was not found between total phosphorus and drainage water. According to the Redfield ratio, nitrogen and phosphorus in the control system 1# keep relative balance, while nitrogen in the control system 2# which has the fewest receiving water plays the role of restriction. With a further increase in the receiving water, phosphorus became a major limiting factor.The effect of effluent on TSS of the receiving water was very significant too. The effluent can raise the soluble inorganic salt notably; it may contribute to the accumulation of inorganic salts in the natural water, and may result in aquatic ecosystem degradation or increase the difficulty of repairing process, which may become more pronounced in arid areas.The effect of effluent on COD、TN、TP in surface sediment of the receiving water was very significant . the effluent dose not cause accumulation and settlement of COD、TN and TP in the sediment, but promote mineralization the organic matter mineral in the sediment and nitrogen and phosphorus released .When restoration of degraded river with plant, as the receiving waters of sewage treatment plants, used the waterweed as a repair plants, can be achieved a better effect than Hyd-rodictyon . A certain amount of effluent can have some form of coercion on the growth of plants, waterweed have stronger resistance to this stress and survive better.When addressed or design the sewage treatment plant, it is best to controlle the ratio of effluent and receiving water volume around 1:100, In the proportion, the effect of effluent met the standard from Sewage Treatment Plant on the receiving waters and subsequent repair plant are relatively small, COD, TN, TP of the receiving water can control at a relatively low level, and repair plant can survived well.更多还原