生产废水联合回用强化混凝效能研究与安全评价

发布时间：2018-06-21 15:38

本文选题：低浊水 + 生产废水回用　；参考：《哈尔滨工业大学》2015年硕士论文

【摘要】：近年来净水厂面临着新饮用水水质标准的不断提高和水源水低浊、水质稳定、微污染等处理难题,净水厂工艺改造势在必行。生产废水直接回用在降低自耗水量的同时可起到强化混凝、节约混凝剂的作用,为净水厂工艺改造提供了一种新的可行方法。然而,生产废水中含有较多的污染物质,其回用的比例和安全性问题成为必须要研究的课题。本文首先对生产废水水质特性进行了试验研究,推测其强化混凝效能并评价直接回用对水质的影响。以混合水浊度为调控参数并考虑温度影响,分别在夏冬季节通过中试试验优化并确定最佳混合水浊度范围,随之进行生产废水连续回用试验,监测生产废水污染物质的浓度变化,对比生产废水回用系统和常规处理系统沉后、滤后出水的理化指标。因理化指标只能反映水体中单一污染物质的瞬时浓度,水体中的污染物质往往通过协同作用、相加作用等方式联合作用于生物体,故首先建立一套生物遗传毒性试验组合,试验组合包括Ames试验、SOS/umu、微核试验(体内和体外)和小鼠精子畸形试验,进而进一步评价生产废水直接回用水质的安全性。试验表明排泥水上清液水质与水源水基本相同,滤池反冲洗废水上清液相关水质指标低于原水,两类生产废水中的有机物质主要以颗粒态或吸附在较大絮体上的方式存在,推断以适当比例回用不会对水质产生较大影响。根据中试试验和相关文献,建议净水厂采用生产废水直接回用工艺时,夏季高温高藻期调节混合水浊度在125~170 NTU区间;冬季低温低浊期调节混合水浊度在40~55 NTU区间。在最佳混合水浊度范围内进行生产废水连续回用试验,结果表明除沉淀池排泥水中Mn元素的微量富集外,两类生产废水中其他污染物质基本无富集现象;在节约混凝剂投加量的情况下,夏季高温高藻期和冬季低温低浊期生产废水回用不会对沉后出水常规指标、有机物指标、Mn含量产生较大影响,回用可强化Al、Fe金属含量的去除,同时在夏季高温高藻期可在一定程度上强化溶解性有机物的去除。夏冬季节生产废水回用和常规处理系统的滤后出水水质基本相同,各项水质指标均满足《生活饮用水卫生标准》(GB5749-2006)的要求。冬季生产废水连续回用末期工艺出水的生物遗传毒性检测表明,生产废水连续回用不会造成移码型突变物的富集,因水源水中抑菌物质较多,无法利用Ames试验判断生产废水回用工艺出水水样致突变性的强弱;根据水样的致阳性等量浓度,生产废水工艺出厂水的致癌风险较低,处于比较安全的水平,同时体外和体内微核试验表明,在试验设计剂量下,生产废水回用工艺出水对染色体无损伤效应,与常规处理工艺无显著性差异。此外生产废水连续回用的沉后出水和滤后消毒水样在试验设计剂量下均无使雄性生殖细胞发生突变的效应。综上结果表明,从生物遗传毒性角度看,在设计的试验剂量下,生产废水连续回用工艺出水的安全性与常规处理工艺基本相同。
[Abstract]:In recent years, water purification plants are faced with the continuous improvement of the water quality standard of new drinking water, low water turbidity, water quality and micro pollution. The process modification of the water purification plant is necessary. The direct reuse of production wastewater can reduce the water consumption and play the role of coagulation, save coagulant, and provide a kind of process transformation for water purification plant. It is a new feasible method. However, there are more pollutants in the production wastewater. The problem of the proportion and safety of its reuse has become a subject that must be studied. Firstly, this paper studies the water quality characteristics of the production wastewater, speculates the strengthening coagulation efficiency and evaluates the effect of direct reuse on the water quality. The turbidity of mixed water is the control parameter. Considering the influence of temperature, the best mixed water turbidity range is optimized in the summer and winter season, and the continuous reuse test of production wastewater is carried out to monitor the change of the concentration of the pollutants in the wastewater. The physical and chemical indexes of the effluent after the wastewater reuse system and the conventional treatment system are compared. The physical and chemical indexes of the effluent are only due to the physical and chemical indexes. It can reflect the instantaneous concentration of a single polluted substance in the water body, and the pollutants in the water body often act together by synergistic action and additive action. Therefore, a set of biological genetic toxicity test combination is first established. The test combination includes Ames test, SOS/umu, micronucleus test (in vivo and in vitro) and sperm abnormality test in mice, and then the test of sperm malformation in mice, The experiment shows that the water quality of the sludge water is basically the same as the water source water, and the water quality index of the filter backwashing wastewater is lower than the original water. The organic matter in the two kinds of production wastewater is mainly in the form of granular or adsorbed on the larger floc, and the appropriate proportion is inferred. Back use does not have a great impact on water quality. According to the pilot test and related literature, it is suggested that the turbidity of mixed water is regulated in the 125~170 NTU interval during the summer high temperature and high algae period, and the turbidity of mixed water in the low temperature and low turbidity period in winter is in the 40~55 NTU zone. The experiment of continuous reuse of wastewater shows that in addition to the trace enrichment of Mn elements in the sludge water of the sedimentation tank, the other pollutants in the two kinds of production wastewater are basically not enriched. In the case of saving coagulant dosage, the reuse of the wastewater in the summer high temperature and high algae period and the low temperature and low turbidity period in winter will not be the conventional index of the effluent after the sedimentation, and the organic matter refers to the effluent. The content of Mn has a great influence on the content of Al, the removal of Fe metal content and the removal of dissolved organic matter in the summer high temperature and high algae period. The water quality of the wastewater reused and the conventional treatment system in summer and winter is basically the same, all the water quality indexes meet the sanitary standard of living drinking water. (GB5749-2006) requirements. The biological genotoxicity test of the effluent from the continuous reuse of the wastewater in winter shows that the continuous reuse of the wastewater will not cause the enrichment of the transcoding mutants, because there are more bacteriostasis in the water source water, and it is impossible to use the Ames test to determine the mutagenicity of the effluent water samples. At the same time, in vitro and in vivo micronucleus test, there is no significant difference between the effluent reused process water and the conventional treatment process. In addition, the production wastewater is reused continuously. The results showed that the safety of the effluent from the continuous recycling process of the wastewater was basically the same as that of the conventional treatment process from the viewpoint of biological genotoxicity.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X703;TU991.22

【参考文献】