异养硝化—好氧反硝化细菌在海水养殖中的应用技术研究

发布时间：2018-05-29 20:04

本文选题：异养硝化-好氧反硝化细菌 + 凡纳滨对虾　；参考：《上海海洋大学》2017年硕士论文

【摘要】：高密度集约化的海水养殖模式导致养殖过程中经常出现养殖水体氮素超标现象,严重威胁海水养殖动物的健康和生长。同时,生产换水后养殖废水的外排,也会加剧周边海域的氮素污染,水体高浓度氮素已经成为导致水体富营养化的主要因素之一,因此加强水产养殖废水脱氮技术的研究有着深远意义。生物脱氮法由于具有低成本、无二次污染、操作简单等优点,常被应用于废水的处理。选择高效优良的脱氮菌株是生物脱氮成功的关键,异养硝化-好氧反硝化细菌为近二十年来筛选出的新型脱氮细菌,突破了人们对传统生物脱氮理论的认识,其利用水体有机物和氮素作为自身碳氮源进行同时硝化反硝化作用,实现生物脱氮。目前,关于异养硝化-好氧反硝化细菌的研究大多数集中在菌种筛选分离与脱氮特性方面,对其应用技术的研究报道尚不多见,尤其在海水养殖环境中应用的报道更少。本文选择本实验室筛选保存的3株异养硝化-好氧反硝化细菌,通过养殖圆斑星鲽废水净化和自制模拟生物滤器对对其进行了多方面的海水养殖应用技术研究,旨在探究菌株的实际应用方法及效果,为进一步建立应用工艺提供依据。主要试验内容与结果如下:(1)选择初始体重为(10.2±1.3)g的凡纳滨对虾,随机分为4组,每组30尾,进行不换水连续养殖。期间分别在养殖水体中加入花津滩芽孢杆菌(Bacillus hwajinpoensis)SLWX2、嗜碱盐单胞菌(Halomonas alkaliphila)X3以及SLWX2+X3复合组。通过测定不同组合各项无机氮及有机物的变化情况检验了它们对养殖水体的净化效果。试验结果显示,养殖过程中,对照组氨氮浓度、亚硝酸氮浓度、硝酸氮浓度、总氮浓度、化学需氧量浓度呈持续上升趋势,而各试验组各项指标第4天有所降低,本研究结果表明添加异养硝化-好氧反硝化细菌可在不添加碳源的情况下实现脱氮的功能,有效维护养殖水质。(2)选择初始体重为(98±6)g的圆斑星鲽,随机分为8组,每组30尾,进行不换水连续养殖。期间分别在养殖水体中加入花津滩芽孢杆菌(Bacillus hwajinpoensis)SLWX2、嗜碱盐单胞菌(Halomonas alkaliphila)X3和麦氏交替单胞菌(Alteromonas macleodii)SLNX2的不同组合。通过测定不同组合中各项无机氮及有机物的变化情况检验了它们对养殖水体的净化效果。试验结果显示,养殖过程中,对照组的氨氮浓度、亚硝酸氮浓度、硝酸氮浓度、总氮浓度、化学需氧量浓度呈持续上升趋势,分别从0.21mg/L升至15.94mg/L,0.08mg/L升至5.68mg/L,1.10mg/L升至7.05mg/L,1.74mg/L升至38.86mg/L,1.19mg/L升至22.87mg/L。而加菌组的各指标浓度一直低于对照组。其中,SLWX2+X3+SLNX2组合对圆斑星鲽养殖废水净化效果最佳,氨氮浓度、亚硝酸氮浓度、硝酸氮浓度、总氮浓度、化学需氧量浓度分别低于对照组68.55%、48.36%、58.38%、40.02%、27.47%。SLWX2+X3组合的净化效果次之。此外,第21天时,对照组因水质差而出现大量死鱼现象,各试验组中仅有少量死鱼。本研究结果表明添加异养硝化-好氧反硝化细菌可在不添加碳源的情况下实现脱氮的功能,有效维护养殖水质,对圆斑星鲽不但无毒害及致病作用,反而因改善其环境而提高了它们的存活率。(3)自制模拟生物滤器,分别接种花津滩芽孢杆菌(Bacillus hwajinpoensis)SLWX2、嗜碱盐单胞菌(Halomonas alkaliphila)X3和麦氏交替单胞菌(Alteromonas macleodii)SLNX2的不同组合进行生物强化挂膜。前期试验探讨了三株细菌不同组合生物膜对静止养殖废水的净化效果。后期试验,选用对各无机氮去除效果最佳的SLWX2+X3+SLNX2组合作为优势菌种再次挂膜,对比分析了优势菌种强化挂膜与自然挂膜两种成熟生物膜对连续运行养殖废水的净化效果效果。静止养殖废水净化试验结果表明:各试验组对养殖废水各项无机氮及有机物指标的去除效果均优于对照组。其中,SLWX2+X3+SLNX2组合对各项指标去除效果最佳,第24h、48h对NH4+-N、NO2--N、CODMn、TN的去除率分别为95.8%、82%、60.8%及100%、100%、80.7%、59.5%。而自然挂膜对照组前24h亚硝酸氮浓度上升,第48h对NH4+-N、NO2--N、CODMn、TN的去除率分别为95.5%、50.52%、38.1%、13.44%。各试验组中NO3--N浓度先上升后下降,而对照组NO3--N浓度呈持续上升,该试验表明添加异养硝化-好氧反硝化细菌可有效地降低养殖废水中氮素和有机物浓度。后期连续运行废水净化试验结果表明:接种优势细菌的试验组对各项无机氮的去除效果均优于自然挂膜组,其中接种量为108cfu/mL的试验组对NH4+-N、NO2--N、NO3--N去除效果均最佳,最大去除率分别为31.6%、11.33%、15.6%,107cfu/ml试验组次之,说明生物强化挂膜对连续运行废水有持续净化能力。
[Abstract]:The high density and intensive aquaculture model often leads to the phenomenon of nitrogen exceeding the standard in aquaculture water, which seriously threatens the health and growth of marine aquaculture animals. At the same time, the production of the outer row of aquaculture wastewater after the production of water exchange also aggravates the nitrogen pollution in the surrounding sea area. The high concentration of nitrogen in the water body has become the main cause of the eutrophication of the water body. As one of the factors, it is of profound significance to strengthen the nitrogen removal technology of aquaculture wastewater. Biological denitrification is often used in the treatment of wastewater because of its advantages of low cost, no two pollution and simple operation. It is the key to choose the high efficient denitrification strain, and the heterotrophic nitrification denitrifying bacteria is nearly two The new type of denitrification bacteria screened in the past ten years has broken through people's understanding of the traditional biological denitrification theory. It uses organic matter and nitrogen as its own carbon and nitrogen source for simultaneous nitrification and denitrification to achieve biological denitrification. At present, most of the studies on heterotrophic nitrification bacteria are concentrated in screening and separation of bacteria. There are few reports on the application of nitrogen characteristics, especially in the aquaculture environment. In this paper, 3 heterotrophic nitrifying aerobic denitrifying bacteria were selected and preserved in our laboratory, and many aspects of marine aquaculture were carried out through the purification of the flounder wastewater and the self-made simulated biofilter. The application technology research was designed to explore the practical application method and effect of strain. The main contents and results were as follows: (1) the shrimp with initial weight of (10.2 + 1.3) g was randomly divided into 4 groups, each group of 30 tails, continuous aquaculture without water exchange. Bacillus hwajinpoensis SLWX2, Halomonas alkaliphila (Halomonas alkaliphila) X3 and SLWX2+X3 composite group. By measuring the changes of inorganic nitrogen and organic matter in different combinations, the effects of their purification on the aquaculture water were tested. The concentration of nitrogenous nitrogen, total nitrogen and chemical oxygen demand increased continuously, and the indexes of each test group decreased for fourth days. The results of this study showed that the addition of heterotrophic nitration aerobic denitrifying bacteria could realize the function of denitrification without adding carbon source and effectively maintain the water quality. (2) the initial weight of (98 + 6) g was selected. Flounder, randomly divided into 8 groups, each group of 30 tails, did not exchange water for continuous culture. During the period, different combinations of Bacillus hwajinpoensis SLWX2, Halomonas alkaliphila X3 and Alteromonas macleodii (Alteromonas macleodii) SLNX2 were added to the aquaculture water respectively. The results showed that the concentration of ammonia nitrogen, nitrite, nitrogen, total nitrogen, and chemical oxygen demand in the control group increased continuously during the culture process, and increased from 0.21mg/L to 15.94mg/L, 0.08mg/L to 5.68mg/L, 1.10mg/L, respectively. To 7.05mg/L, 1.74mg/L to 38.86mg/L and 1.19mg/L to 22.87mg/L., the concentration of each index in the addition of bacteria was lower than that of the control group. Among them, the SLWX2+X3+SLNX2 combination had the best purification effect on the flounder aquaculture wastewater, and the concentration of ammonia nitrogen, nitrite, nitrogen, total nitrogen, and the concentration of total nitrogen, and the concentration of chemical oxygen demand were 68.55%, 4 respectively. The purification effect of 8.36%, 58.38%, 40.02%, 27.47%.SLWX2+X3 combination was second. In addition, a large number of dead fish appeared in the control group because of poor water quality at twenty-first days. Only a small amount of dead fish were found in the experimental groups. The results of this study showed that the addition of heterotrophic nitration aerobic denitrifying bacteria could realize the function of denitrification without the addition of carbon source and effectively maintain the culture. Water quality, not only did no toxic and pathogenic effects on the flounder, but improved their survival rate by improving their environment. (3) a self-made simulated biofilter, respectively, inoculated with Bacillus subtilis (Bacillus hwajinpoensis) SLWX2, Halomonas alkaliphila X3 and Alteromonas macleodii SLNX2 (Alteromonas macleodii) SLNX2 The effect of three bacteria different combination biofilms on the purification of stationary aquaculture wastewater was studied in the previous experiment. In the later experiment, the best SLWX2+X3+SLNX2 combination of the inorganic nitrogen removal effect was selected as the dominant strain to hang the film again, and two kinds of dominant strains were compared and analyzed. The results of the static culture wastewater purification test showed that the removal efficiency of various inorganic nitrogen and organic matter indexes of each test group was better than that of the control group. Among them, the SLWX2+X3+SLNX2 combination had the best effect on the removal of various indexes, and 24h, 48h to NH4+-N, NO2--N, CODMn, TN. The removal rates were 95.8%, 82%, 60.8% and 100%, 100%, 80.7%, 59.5%., while the concentration of 24h nitrite in the natural film control group increased, and the removal rates of NH4+-N, NO2--N, CODMn, TN were 95.5%, 50.52%, 38.1%, respectively, and then the NO3--N concentration in the experimental groups of 13.44%. increased first and then decreased, while the NO3--N concentration in the control group rose continuously. The experiment showed that the addition of NO3--N was added. Heterotrophic nitrification and aerobic denitrifying bacteria can effectively reduce the concentration of nitrogen and organic matter in aquaculture wastewater. The results of the later continuous operation of wastewater purification test show that the removal efficiency of inorganic nitrogen in the experimental group with inoculated dominant bacteria is better than that of the natural film group, and the test group with the inoculation amount of 108cfu/mL for the removal of NH4+-N, NO2--N, and NO3--N The results were all the best, the maximum removal rates were 31.6%, 11.33%, 15.6%, and the 107cfu/ml test group was the next, indicating that the biofilm has a continuous purification capacity for the continuous operation of wastewater.
【学位授予单位】：上海海洋大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X714;X172

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