城市污水回用于火力发电厂循环冷却水研究

【作者】 武红霞；

【导师】 刘裕明； 陈慧英；

【作者基本信息】 中央民族大学 ， 生态学， 2004， 硕士

【摘要】 在水资源日益短缺的今天，经过污水处理厂二级处理后的城市污水完全可以作为城市的第二水源来利用。火力发电厂是城市工业用水大户，其循环冷却水不直接和人体接触、水质要求不高、水量需求大，因而它是城市污水最大的潜在用户之一。 以北京市高碑店污水处理厂二级处理出水回用作华能北京热电厂循环冷却水，这一实际回用工程为依托，本论文评价、总结了城市污水在其处理和回用作火力发电厂循环冷却水的过程中水质的变化情况，分析了水质与循环冷却水系统常见问题之间的关系，提出了一些对城市污水回用于火力发电厂循环冷却水具有实际指导意义的结论。 首先，本论文通过对整个污水回用工程情况的考察，掌握影响污水回用工程的关键因素，以及水质变化过程。通过对2003年的水质指标的分析，发现经过二级处理后，出水水质稳定。由于氨氮浓度对回用水系统的特殊危害，本文特别探讨了影响氨氮去除率的因素；经过预处理后，二级处理出水的水质(尤其是硬度、碱度、pH值等与回用效果密切相关的水质指标)有了极大的改善；经过对电厂中缓蚀阻垢和杀菌灭藻两方面工作的考察和研究，提出了有效的水质稳定措施。此外，本文还提出了循环水水质在冷却水系统中的变化规律及相应的原因。 之后，本文分析了影响回用的关键因素，并对各因素造成的问题提出了相应的对策。污水回用于冷却水系统时常见的问题可以归纳为：结垢、金属腐蚀和微生物滋生三个方面。本文从多个方面判断了经过预处理后的二级处理出水的水质稳定性，得出了该水质为腐蚀性水的结论。浓缩倍数的控制以及有机物浓度、氨氮浓度都是污水回用中的关键因素。通过挂片试验，提出有机物、氨氮和金属腐蚀的关系。 接下来，论文对污水回用工程进行了成本分析。循环水预处理的成本2003年为0.83元/m3，20ox年、2002年的处理成本均为0.81元/m3，其中药品费用所占比例最大，为35%左右。循环冷却水的水质稳定处理费用2003年由前两年的0.1元/m，左右，增加到了0.53元/m3。费用的增加是由氧化性杀菌剂氯锭的使用造成的。 最后对整个论文的研究结果进行了总结。更多还原

【Abstract】 In the day water resource is short increasingly. It can be used as the secondary source of water entirely the municipal sewage treated secondarily by the sewage treating plant. The thermal power plant is the big consumer, and the circulating cooling water in it doesn’t contract with people, require lower water quality and higher water quantity. Then, the power plant is the biggest potential consumer.The paper is supported by the project of the reusing waste water treated secondarily from the Sewage treating Plant of Gaobeidian in Beijing as the circulating cooling water in the Huaneng cent-company in Beijing. It summarizes the change of water quality in the process of sewage treating and of being used as the circulating cooling water in the thermal power plant, analyzes the relation between water quality and some common matters, in the end comes to some conclusions that are guides to the municipal sewage reusing as the circulating cooling water in the thermal power plant.Reviewing the entire reusing project, we grasp the key factors influencing the reusing engineering and the changing process of water quality. After secondary treating, the water quality is steady. Because NH4-N do special harm to the circulating water system, the removal of NH4-N is inquired. After pre-treating, the quality of the water bysecondary treating improves greatly. Through reviewing two ways, the cut corrosion and scale and sterilization, the paper raises the effective measures to immune metal from corrosion and to stop the scale come forth. In the part, the water quality change and its corresponding cause are*proposed in cooling water system.Then, the paper analyzes the key factors affecting reusing and suggests the methods. The common matters during sewage reusing as circulating cooling water are the scale, metal corrosion and microbe development. It is concluded that the water after pre-treating is caustic in many ways. The control to condense multiple, organism and NH4-N are the key factors. Through metal hanging slice test, the connection between organic pollutants and NH4-N and metal corrosion is raised.Following on, the paper analyzes the cost of the sewage reusing object. The cost of circulating water pre-treating is 0.83 yuan/m3 in 2003, and 0.81 yuan/m3 in 200land 2002. In it, the cost of chemicals is the highest, about 35%. The cost of circulating treating for water quality steady is 0.53 yuan/m3 in 2003, but is about 0.1 yuan/m3 in the past two years. Using the chlorine ingot is the cause’of the increase in the cost.At last, it is summed up the outcomes of the paper in entire research.更多还原