强化生物滴滤技术处理间二氯苯废气工艺研究

发布时间：2018-06-30 00:01

  本文选题：生物滴滤塔 + 间二氯苯　； 参考：《江苏大学》2017年硕士论文

【摘要】：挥发性有机物(VOCs--Volatile Organic Compounds)的排放问题已成为重要的环境问题之一。目前,虽然生物滴滤器(BTF---Biotrickling filters)能有效处理一些VOCs,但是其对疏水性有机物处理效果不佳。优势菌强化及表面活性剂与金属离子协同强化都是对强化生物滴滤技术处理疏水性VOCs有效方法。在本研究中,间二氯苯作为一种疏水性VOCs被选为研究对象。利用富集培养技术和无菌滤纸片平板法分离纯化具有间二氯苯降解能力的优势菌株,并对其进行形态学观察、生理生化试验、16S rRNA基因序列的同源性分析,及优势菌种的降解特性进行研究。结果表明,筛选到5株(分别标记为DH-1、DH-2、DH-3、DH-4和DH-5)具有间二氯苯降解能力的优势菌种,其去除率分别为75.4%、74.8%、70.1%、67.5%和50.7%。针对DH 1菌和DH-2菌的形态学和生理生化试验表明,细胞均呈杆状,有鞭毛、芽孢和荚膜,革兰氏阳性,能使明胶液化、淀粉水解。16S rRNA基因序列相似性比较进一步表明DH-1菌和DH-2菌与Brevibacillus agri(土壤短芽孢杆菌)的相似性达94%以上,因此鉴定DH-1和DH-2为Brevibacillus agri。选取DH-1菌进行的降解性能测定表明,最适降解时间、初始浓度、菌体接种量、pH和温度分别为2 d、130 mg/L、10%、7和30℃。以间二氯苯为单一碳源,研究不同浓度的鼠李糖脂、Fe~(3+)和Mg~(2+)对土壤短芽孢杆菌DH-1的生长状况及间二氯苯降解效率的影响,通过响应面优化法获得最适浓度。鼠李糖脂、Fe~(3+)及Mg~(2+)均会对DH-1菌的生长、间二氯苯的去除效率产生影响;利用响应面模型优化获得鼠李糖脂、Fe~(3+)和Mg~(2+)的最适添加浓度分别为150 mg/L、5 mg/L、2 mg/L。在最适条件下培养2 d后,菌种密度较大且形成菌团,菌种正处于高活性状态,培养3 d后,对间二氯苯的降解效率可达98.94%,对比空白实验,其降解效率提升了25.32%。同时启动三个同样的生物滴滤塔(BTF1、BTF2、BTF3),研究鼠李糖脂、Fe~(3+)和Mg~(2+)对间二氯苯降解和DH-1菌生长的影响,最终得到鼠李糖脂、Fe~(3+)和Mg~(2+)在生物滴滤塔中的的最佳添加量,分别为170 mg/L、4 mg/L和2 mg/L。三种添加物质的交互作用实验结果表明,Fe~(3+)及Mg~(2+)可以较为明显的提升鼠李糖脂的强化作用。通过BTF1和BTF2研究添加最适量的鼠李糖脂、Fe~(3+)和Mg~(2+)后,在不同EBRT及进气负荷下对生物滴滤塔处理间二氯苯的强化作用。结果表明鼠李糖脂、Fe~(3+)和Mg~(2+)可以较大幅度地提升生物滴滤塔去除间二氯苯的能力。对整个滴滤塔实验过程的溶解氧检测的结果也说明鼠李糖脂、Fe~(3+)和Mg~(2+)很大程度的改善了氧气传质和运行稳定性。
[Abstract]:The emission of volatile organic compounds (VOCs) has become one of the most important environmental problems. At present, BTF-Biotrickling filters (BTF-Biotrickling filters) can effectively treat some VOCs, but it is not effective in treating hydrophobic organic matter. The enhancement of dominant bacteria and the synergistic enhancement of surfactant and metal ions are effective methods for the treatment of hydrophobic VOCs by enhanced biofiltration. In this study, m-dichlorobenzene was selected as a hydrophobic VOCs. Predominance strains with m-dichlorobenzene degradation were isolated and purified by enrichment culture technique and aseptic filter plate method. Morphological observation and homology analysis of 16s rRNA gene sequence in physiological and biochemical tests were carried out. And the degradation characteristics of dominant strains were studied. The results showed that 5 strains (labeled DH-1DH-2DH-3DH-4 and DH-5) had the ability to degrade m-dichlorobenzene, and the removal rates were 75.4% and 50.7%, respectively. The morphological, physiological and biochemical tests of DH1 and DH-2 showed that the cells were rod shaped, flagella, spore and capsule, Gram-positive, and could liquefy gelatin. The similarity between DH-1 and DH-2 strains and Brevibacillus agri was more than 94%, so DH-1 and DH-2 were identified as Brevibacillus agrius. The optimum degradation time, initial concentration, inoculation amount, pH and temperature of DH-1 strain were 2 d ~ 130 mg / L ~ 10 鈩，

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