【摘要】：本研究從山東某水庫沉積物、人工強化無沉積物原水、人工強化有沉積物原水及水庫水體中篩選出27種脫氮效果良好的好氧反硝化混合菌群,并從其中的10#混合菌群中純化分離出兩株高效好氧反硝化菌,將其命名為SF9和ZHF3。經(jīng)16S rDNA序列分析確定菌株SF9和ZHF3分別為代爾夫特菌(Delftia sp.)和不動桿菌(Acinetobacte sp.)。以10#混合菌群為菌源對其進行脫氮特性研究,研究表明在C/N比為2、4、6、8四個梯度下,反硝化脫氮效果隨著C/N升高而增強越高;通過在水庫不同深度掛硬質(zhì)瓶和軟質(zhì)瓶來考察溫度和壓力對菌群脫氮效果的影響,結果表明溫度從水庫底層的11℃到表層28℃范圍內(nèi),溫度越高反硝化效果越好,表層28℃下可在48 h將硝氮完全去除,而底層11℃下直到144 h才完全去除硝氮。對相同深度的軟瓶和硬瓶對比可知壓力會對菌群的脫氮效果產(chǎn)生影響,盡管如此,底層軟瓶在11℃低溫和15 m水壓雙重作用下硝氮仍去除65%,體現(xiàn)出混合菌群對水庫環(huán)境的適應性強的特性。對菌株SF9和ZHF3進行脫氮特性分析,好氧條件下菌株SF9和ZHF3在以硝氮為唯一氮源的培養(yǎng)基中可發(fā)揮反硝化作用并同步去除TOC,SF9和ZHF3對硝氮去除率分別達到81%和77%,TOC去除率均達到100%。SF9和ZHF3在以亞硝氮為唯一氮源的培養(yǎng)基中對亞硝氮去除率分別為64%和79%。在以氨氮為唯一氮源時,SF9和ZHF3對氨氮去除率分別為40%和45%,同時TOC均完全去除,可見菌株具有異養(yǎng)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+亞硝氮(SND2)的培養(yǎng)基中會優(yōu)先利用氨氮。對10#混合菌群進行原水試驗,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,室溫控制溶解氧在3-5 mg/L,以不加菌液的系統(tǒng)作為空白對照,結果表明投菌系統(tǒng)總氮在40天結束時去除率達46%,空白系統(tǒng)總氮基本維持不變,平板計數(shù)可知投菌系統(tǒng)中反硝化菌數(shù)高于空白系統(tǒng)1-2個數(shù)量級,體現(xiàn)混合菌群在原水中發(fā)揮了作用,在微污染水源水微生物脫氮方面具有應用價值。
[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，

本文編號：2279099