高效藻塘与复合型人工湿地耦合系统处理重金属废水的研究

发布时间：2018-05-31 23:31

本文选题：高效藻塘 + 人工湿地　；参考：《东华大学》2015年硕士论文

【摘要】：高效藻塘藻菌共生系统与人工湿地已成为低成本水处理技术的重要选择之一。构建高效藻塘与复合型富氧人工湿地耦合生态系统，形成藻类-细菌-湿地沉水植物的代谢共生体系和自动增氧人工湿地对重金属协同进化过程。通过实验分析耦合系统中影响重金属去除的因素，对比各种组合下重金属去除效果，确定耦合系统运行优化参数。结合实验数据及理论分析表明：高效藻塘的藻浓度与重金属去除效果具有直接联系，温度、光照和氮磷比等环境因素通过影响高效藻塘中的藻菌的生长，间接的影响重金属去除效果。温度与光照强度是影响藻浓度增殖的显著性影响因素，光照时间与氮磷比不是影响藻浓度增殖的显著性影响因素。人工湿地中基质对重金属的吸附量随进水pH升高而增大，湿地填充的三种基质对三种重金属的吸附量大小顺序为黄沙细石英砂粗石英砂。喷灌进水对重金属的去除效果优于滴灌进水，单位重量下美人蕉的根吸收富集量要远大于茎叶的富集量。滴灌进水下美人蕉根富集重金属量大于喷淋进水下根的富集量，但喷淋进水下茎叶的富集量大于滴灌进水富集量。经过耦合系统处理后，生活废水中的Zn、Cr、Pb三种重金属的平均去除率达到94.4%、93.2%、98.8%，高效的去除了废水中的重金属。耦合系统三个处理单元中高效藻塘起主要作用，去除重金属量最多，约占总去除量的60%。在高效藻塘中，重金属的去除主要是依靠藻类的吸附代谢，，Zn、Cr、Pb三种重金属依靠沉淀及微生物代谢作用去除的比例依次为8.7%、21.4%、19.1%。在16000cells·mL-1藻浓度下，单位体积的高效藻塘藻类对铬、锌铅的最终吸附量分别为352.74ug、2657.28ug、1443.86ug。1g干藻粉能吸附铬、锌、铅的平局量分别为0.92mg、4.34mg、2.05mg，整个预处理池干藻吸附的重金属量基本等于水中重金属的去除总量，表明冬季利用藻粉能够去除废水中的重金属。滴灌进水下美人蕉根部每千克富集Zn、Cr、Pb的量分别为925.6mg、261.6mg、494.1mg，均高于喷灌进水下Zn、Cr、Pb的540.9mg、86.1mg、352.3mg富集量，在滴灌进水下茎叶中重金属含量相对于空白对照无明显增长，喷灌进水下茎叶重金属富集量远远高于滴灌，Zn、Cr、Pb的富集量分别为113.6mg、64.5mg、31.1mg。
[Abstract]:High efficiency algal pond algae symbiotic system and constructed wetland have become one of the important choices of low cost water treatment technology. An efficient algal pond coupled with a complex oxygen-enriched constructed wetland was constructed to form a symbiotic metabolic system of alga-bacteria-wetland submerged plants and a co-evolution process of heavy metals in an autooxygenated constructed wetland. The factors affecting the removal of heavy metals in the coupled system are analyzed experimentally and the operation optimization parameters of the coupling system are determined by comparing the removal effects of heavy metals under various combinations. Combined with the experimental data and theoretical analysis, it was shown that the algae concentration in the efficient algal pond was directly related to the removal efficiency of heavy metals, and the environmental factors, such as temperature, light and ratio of nitrogen to phosphorus, affected the growth of algal bacteria in the high efficiency algal pond. Indirect effects on the removal of heavy metals. Temperature and light intensity were significant influencing factors of algae concentration proliferation, and the ratio of light time to nitrogen and phosphorus was not the significant factor affecting algal concentration proliferation. The amount of heavy metals adsorbed by substrates in constructed wetland increased with the increase of influent pH, and the order of adsorption amount of three substrates filled with wetland for three heavy metals was yellow sand fine quartz sand coarse quartz sand. The removal of heavy metals by sprinkler irrigation was better than that by drip irrigation, and the root absorption and enrichment of Canna per unit weight was much larger than that of stem and leaf. The accumulation of heavy metals in Canna root under drip irrigation was greater than that in the root of spraying water, but the enrichment amount of stem and leaf in spraying water was greater than that in drip irrigation. After the coupled system treatment, the average removal rate of the three heavy metals in the domestic wastewater is 94.4% and 93.2% (98.8%), which can effectively remove the heavy metals in the wastewater. The high efficiency algal pond plays a major role in the three treatment units of the coupling system, and the removal of heavy metals is the most, accounting for about 60 percent of the total removal amount. In the high efficiency algal pond, the removal of heavy metals mainly depends on the adsorption and metabolism of algae. The proportion of heavy metal removal by precipitation and microbial metabolism is 8.7 and 21.4g / 19.1respectively. At the concentration of 16000cells mL-1, the final adsorption capacity of chromium, zinc and lead for algae per unit volume of high efficiency algal pond is 352.74ugn 2657.28ugn 1443.86ug.1g dry algae powder can adsorb chromium and zinc, respectively. The level of lead was 0.92 mg / g ~ 4.34 mg / g ~ 2.05 mg / g respectively. The amount of heavy metals adsorbed by the whole pretreatment pool was basically equal to the total amount of heavy metals in water, which indicated that the utilization of algae powder in winter could remove heavy metals in wastewater. Under drip irrigation, the accumulations of Zn ~ (2 +) Cr ~ (+) Pb in the roots of Canna plantain were 925.6 mg / kg ~ 261.6 mg / kg ~ 494.1 mg / kg, respectively, which were higher than that of ~ (54. 9) mg ~ (-1) mg ~ (86. 1) mg ~ (-1) mg of Zn ~ (2 +) Cr ~ (2 +) ~ (2 +) and Pb ~ (2 +) under sprinkler irrigation, but the contents of heavy metals in stems and leaves of stems and leaves under drip irrigation did not increase significantly compared with the control. The accumulation of heavy metals in stems and leaves under sprinkler irrigation was much higher than that in drip irrigation, which was 113.6 mg / g of 64.5mg / g ~ 31.1 mg / g respectively.
【学位授予单位】：东华大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X703.1

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