贫营养好氧反硝化混合菌群的筛选鉴定和脱氮特性研究

发布时间：2018-10-18 12:17

【摘要】：本研究从山东某水库沉积物、人工强化无沉积物原水、人工强化有沉积物原水及水库水体中筛选出27种脱氮效果良好的好氧反硝化混合菌群,并从其中的10#混合菌群中纯化分离出两株高效好氧反硝化菌,将其命名为SF9和ZHF3。经16S rDNA序列分析确定菌株SF9和ZHF3分别为代尔夫特菌(Delftia sp.)和不动杆菌(Acinetobacte sp.)。以10#混合菌群为菌源对其进行脱氮特性研究,研究表明在C/N比为2、4、6、8四个梯度下,反硝化脱氮效果随着C/N升高而增强越高;通过在水库不同深度挂硬质瓶和软质瓶来考察温度和压力对菌群脱氮效果的影响,结果表明温度从水库底层的11℃到表层28℃范围内,温度越高反硝化效果越好,表层28℃下可在48 h将硝氮完全去除,而底层11℃下直到144 h才完全去除硝氮。对相同深度的软瓶和硬瓶对比可知压力会对菌群的脱氮效果产生影响,尽管如此,底层软瓶在11℃低温和15 m水压双重作用下硝氮仍去除65%,体现出混合菌群对水库环境的适应性强的特性。对菌株SF9和ZHF3进行脱氮特性分析,好氧条件下菌株SF9和ZHF3在以硝氮为唯一氮源的培养基中可发挥反硝化作用并同步去除TOC,SF9和ZHF3对硝氮去除率分别达到81%和77%,TOC去除率均达到100%。SF9和ZHF3在以亚硝氮为唯一氮源的培养基中对亚硝氮去除率分别为64%和79%。在以氨氮为唯一氮源时,SF9和ZHF3对氨氮去除率分别为40%和45%,同时TOC均完全去除,可见菌株具有异养硝化功能。同步硝化反硝化研究表明菌株SF9和ZHF3在氨氮+硝氮(SND1)及氨氮+亚硝氮(SND2)的培养基中会优先利用氨氮。对10#混合菌群进行原水试验,在20 L玻璃瓶中以20 ml/20 L投菌量投加活化好的10#混合菌群菌液,室温控制溶解氧在3-5 mg/L,以不加菌液的系统作为空白对照,结果表明投菌系统总氮在40天结束时去除率达46%,空白系统总氮基本维持不变,平板计数可知投菌系统中反硝化菌数高于空白系统1-2个数量级,体现混合菌群在原水中发挥了作用,在微污染水源水微生物脱氮方面具有应用价值。
[Abstract]:In this study, 27 aerobic denitrification mixed bacteria with good denitrification effect were selected from the sediments of a certain reservoir in Shandong Province, the raw water without sediment, the raw water with sediment and the water of the reservoir. Two strains of aerobic denitrifying bacteria were purified from the mixed colony of 10# and named SF9 and ZHF3.. The 16s rDNA sequence analysis confirmed that SF9 and ZHF3 were (Delftia sp.) respectively. Acinetobacter (Acinetobacte sp.). The denitrification characteristics of 10# mixed bacteria were studied. The results showed that denitrification effect increased with the increase of C / N when the C / N ratio was 2 ~ 4 ~ 6 ~ 6 ~ (8) gradient. The effects of temperature and pressure on denitrification were investigated by hanging rigid and soft bottles at different depths of the reservoir. The results showed that the higher the temperature was, the better the denitrification effect was when the temperature ranged from 11 鈩，

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