特殊氮細菌之分離及其於同時去除廢水中碳氮之研究

Isolation of specific nitrogen-bacteria and studies on their applications for simultaneous carbon and nitrogen removal from wastewater

吳依龍(Yi-Lung Wu)

指導教授 ： 曾四恭

國立臺灣大學/工學院/環境工程學研究所/碩士(2006年)

https://doi.org/10.6342/NTU.2006.02355

摘要

本研究擬由本土環境中分離出適於本土環境氣候，並能處理畜牧廢水之異營性硝化菌，應用於畜牧廢水中氮的去除，其目的在於提升廢水中氮碳去除功能以及降低處理成本。為了增加這些微生物在廢水處理反應槽之競爭力､停留時間､及細胞濃度，擬以細胞固定化技術來達成。

同時硝化脫硝之異營硝化菌的應用，可以單槽進行硝化及脫硝反應，直接將TKN及NH3轉化為氮氣，可省簡化傳統除氮單元之設置，又因脫硝產生鹼度可以中和硝化所產生的酸度，而減少了廢水pH的變化幅度，同時硝化脫硝反應所消耗的碳源部分來自廢水中之COD，可達成同時去除氮及COD之功能，減少外加碳源所增加之成本。異營硝化菌亦可單純當作生物製劑應用在COD濃度高而硝化效率低的硝化槽，應可提高硝化效率及COD之去除效率。另外，對於異營性硝化作用之機制與特性，以及其於反應槽內隨時間空間之分佈等問題若能加以進一步的探索，相信對於增進傳統除氮系統效率之研究必然有很大的助益。

本研究目前已成功自土壤､水田溝渠以及養豬廢水曝氣槽篩選出十餘株本土異營性硝化菌，並完成部分菌株之同時硝化脫硝特性試驗及16S rDNA序列鑑定。其中菌株slg-c-6具有較高的同時消化脫硝能力，以16S rDNA序列鑑定為Achromobacter oxylosoxidans subsp. oxylosoxidans，目前還未有關於同時硝化脫硝之研究報告。將配合薄膜間接供氣反應槽及固定化細胞技術將其應用在畜牧廢水之處理上，探討合適之操作條件，並利用相關分子生物技術針對其於反應槽內實際操作之優勢性加以追蹤，以進一步瞭解此菌種於反應槽內之消長，進而評估此一技術之可行性，期能達成同槽硝化脫硝之目標。此一同時硝化脫硝之系統可望能大幅降低傳統硝化脫硝兩槽系統之成本及操作問題，並有助於兼顧相關產業之永續發展與環境保護之考量。

關鍵字

同時硝化脫硝 ； 廢水處裡 ； 固定化 ； 異營硝化

並列摘要

This research is to estimate the feasibility of a system using specific nitrogen bacteria ─ the heterotrophic nitrifiers, to remove nitrogen from swine wastewater with better performance. Another purpose is to improve nitrogen and COD removal from wastewater and reduce the overall operation cost. By concerning the possibly lower competitivity of these microorganisms under realistic environment, the immobilization technique is introduced to increase their chance to survive and make the single-reactor nitrification/denitrification process practicable. Isolation and immobilization of native heterotrophic nitrification bacteria with or without simultaneously nitrifying and denitrifying ability will be carried out and immobilized or co-immobilized with aerobic denitrifiers if needed, performing single-reactor SND, TKN and ammonium can be converted directly into nitrogen gas without an additional anoxic tank. This single reactor has some advantages than the traditional ones: the alkalinity produced from denitrification process can neutralize the acidity formed from nitrification activity, so that the range of pH change is mitigated. Further more, less or no additional carbon source may be required since the organic carbon demand for the denitrification reaction is directly consumed from wastewater COD, so that the purpose of removing nitrogen and COD can be achieved simultaneously, and the total operation cost will be reduced. Besides, we also intend to apply the heterotrophic nitrifiers to improve the nitrification and COD removal efficiency of those reactors containing high-level COD.

Presently, over 200 strains of bacteria have been isolated from paddy field drains, soil and swine wastewater treatment systems respectively. 10 strains of them showed significant heterotrophic nitrification and were isolated and purified. Culture purity, scientific name and relative gene information of these isolated heterotrophic nitrifiers were determined by applying their 16s rDNA sequencing data to NCBI 16srDNA database. Biochemical characteristics of isolated microbes have also been carried out, the strain slg-c-6 shows significant nitrogen removal and was identified as Achromobacter oxylosoxidans subsp. oxylosoxidans with 16S rDNA sequence aliment.

The purpose set for future works is to estimate the improvement of nitrogen and COD removal from swine wastewater treatment by applying immobilized heterotrophic nitrifiers. Investigation of the efficiency and feasibility of simultaneously nitrification and denitrification of inoculated heterotrophic nitrifiers for swine wastewater treatment will also be carried out with appropriate techniques of molecular biology.

並列關鍵字

SND ； wastewater treatment ； immobilizaion ； heterotrophic nitrificaion

參考文獻

莊隆光。2004。『固定特殊氮細菌進行單槽碳氮去除之研究』。國

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