基于小球藻培养的市政污水处理研究

发布时间：2018-02-11 19:33

本文关键词： 小球藻污水处理市政污水藻菌共生　出处：《湖北工业大学》2017年硕士论文　论文类型：学位论文

【摘要】：微藻对不同浓度的污水具有良好的耐受性,并且能够在处理污水过程中获得高附加值产物,不同于传统污水处理技术和高端处理设备,利用微藻处理污水有望实现污水处理过程中的“收支平衡”,微藻不仅易于培养,在处理污水过程中还能减少碳排放。许多研究证明微藻在处理人工合成污水或者在室内实验条件下,均对小体积的污水有较好的处理效果,然而这些研究距离微藻处理污水产业化要求还有较大差距。本课题选用一株对污水耐受性好,生长迅速,吸收氮磷能力强的小球藻(Chlorella zofingiensis),研究其在在室外自然光条件下大规模处理污水处理厂尾水及市政污水的效果,并考察了其在处理污水时的产油能力,综合评估该株藻应用于城市污水处理并实现工业化的潜力。主要研究内容及研究结果如下:(1)对小球藻生长条件优化的探究得出,小球藻的生长最佳接种OD为1.2,通气量为1L·min-1,而且在光生物反应器厚度为1cm时,小球藻对尾水的处理效果最好,总氮、总磷的去除率分别达96.6%、97.7%;(2)在室外大型平板式光生物反应器中对活性污泥法出水进行小球藻的批次培养处理,夏季实验总磷可以处理至0.06mg·L-1去除率为78.96%,冬季实验总磷处理至0.29mg·L-1,去除率87.64%,两次实验的COD的去除率分别为72.13%和66.74%,最高可获得0.43g·L-1的生物量,油脂含量为25.57%。(3)在室外大型平板式光生物反应器中对市政污水进行小球藻的批次培养处理,春季和夏季实验中对氨氮的最终去除率分别为94.05%和99.86%,对总氮的最终去除率为91.73%和99.73%,COD的去除率分别为86.55%和78.72%,BOD5的去除率分别达89.87%和83.38%。市政污水中碳源充足,小球藻对总氮的去除相较于处理尾水的效果有显著的提升。(4)为提高小球藻对有机物的去除率,加入活性污泥中的好氧菌与小球藻构建藻菌共生体系处理污水,根据不同藻菌比例做藻菌共生实验,测定小球藻的生长情况得出最佳藻菌混合比例为藻:菌=10:1;在室内进行10:1藻菌共生处理原水,氨氮去除率最高达96.61%,总氮达85.16%,总磷24h内处理率达95.87%,而且最高可收获0.92g·L-1的生物量。(5)在室外大型平板式光生物反应器中对市政污水进行藻菌共生体系的批次培养处理,并与独立小球藻系统处理污水进行比较。实验结果显示氨氮处理率达96.61%,总氮处理率达85.16%,总磷处理率达95.87%,而且相较于独立小球藻系统能在短时间内得到更好的脱氮除磷效果,实验结束时可收获0.45g·L-1的干物质。小球藻不仅能处理活性污泥法出水也能在不同气候条件下对市政污水有良好的处理效果,藻菌共生相对于小球藻在同样的处理时间内能得到更好的处理效果,小球藻在污水处理应用上有巨大的潜力。
[Abstract]:Microalgae have good tolerance to different concentrations of sewage, and can obtain high value-added products in the process of sewage treatment, which is different from the traditional sewage treatment technology and high-end treatment equipment. Using microalgae to treat sewage is expected to achieve "budget balance" in the process of sewage treatment, microalgae are not only easy to cultivate, Many studies have shown that microalgae have better effects on treating small volumes of sewage in the treatment of synthetic sewage or in laboratory experiments. However, there is still a big gap between these studies and the industrialization requirements of microalgae wastewater treatment. Chlorella zofingiensis (Chlorella zofingiensis), which has strong nitrogen and phosphorus absorption ability, was used to study the effect of large-scale treatment of sewage treatment plant tail water and municipal sewage under outdoor natural light conditions, and the oil production capacity of Chlorella zofingiensis was investigated. The main contents and results of this study are as follows: 1) the optimization of the growth conditions of Chlorella vulgaris was studied. The optimum inoculation of Chlorella vulgaris was 1.2, the aeration rate was 1L 路min-1, and when the thickness of photobioreactor was 1cm, Chlorella vulgaris had the best effect on the treatment of tail water, and the total nitrogen was the best. The removal rate of total phosphorus reached 96.6and 97.7g / 2 respectively) the effluent from activated sludge process was treated by batch culture of Chlorella vulgaris in an outdoor large plate photobioreactor. The removal rate of total phosphorus was 78.96 mg 路L ~ (-1) in summer, 0.29 mg 路L ~ (-1) in winter, and 87.64% in winter. The COD removal rates of the two experiments were 72.13% and 66.74, respectively. The highest biomass of 0.43 g 路L ~ (-1) was obtained. The oil content was 25.57%.) the municipal sewage was cultured in lots of chlorella in outdoor flat-plate photobioreactor. In spring and summer experiments, the final removal rates of ammonia nitrogen and total nitrogen were 94.05% and 99.86, respectively, and the final removal rates of total nitrogen and total nitrogen were 91.73% and 99.73, respectively. The removal rates of BOD5 and BOD5 were 86.55% and 78.72, respectively. In order to improve the removal rate of organic matter by Chlorella vulgaris, aerobic bacteria and Chlorella microphylla were added to the activated sludge to construct a symbiotic system of algal bacteria to treat wastewater. According to the experiment of algae symbiosis with different proportion of algae, the growth of Chlorella microphylla was determined. The best proportion of algal bacteria was alga: 10: 1; the raw water was treated by symbiotic treatment of 10: 1. The highest removal rate of ammonia nitrogen was 96.61%, the total nitrogen reached 85.16%, the total phosphorus treatment rate reached 95.87 in 24 hours, and the highest yield was 0.92g 路L ~ (-1) biomass. The experimental results showed that ammonia nitrogen treatment rate was 96.61%, total nitrogen treatment rate was 85.16%, total phosphorus treatment rate was 95.877.In addition, compared with independent Chlorella vulgaris system, nitrogen and phosphorus removal efficiency was better than that of independent Chlorella vulgaris system in a short time, the results showed that ammonia nitrogen treatment rate reached 96.61%, total nitrogen treatment rate reached 85.16% and total phosphorus treatment rate reached 95.87%. At the end of the experiment, the dry matter of 0.45 g 路L -1 can be harvested. Chlorella vulgaris can not only treat the effluent from activated sludge process but also treat municipal sewage under different climatic conditions. Compared with Chlorella vulgaris, algae symbiosis can get better treatment effect in the same treatment time, and Chlorella microphylla has great potential in sewage treatment.
【学位授予单位】：湖北工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X703

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