利用固定化細胞於氨氮亞硝酸鹽化之研究

Abstract

傳統生物脫氮技術在低氨氮濃度、高碳源的水處理廠中己獲得廣泛利用，但對於氨氮濃度高且C/N比偏低的廢水，其氨佳。尤其氨氮亞硝酸鹽化比傳統的生物脫氮程序可具氮去除效果則反應不有低耗能、降低碳源供給、反應時間降低等優點；固定化技術除具有保護微生物不易流失外還兼具增加微生物對周遭不良環境負荷之抵抗力之優點，兩者都算是目前廢水處理的研究重點之一。 本研究利用亞硝酸鹽化技術與固定化優點，將氨氧化菌污泥加以固定化研討其亞硝酸鹽化反應之能力，包括氨氮之降解能力及亞硝酸鹽氮的生成速率，評估這項技術的可行性，試驗分別以懸浮性含氨氧化菌之污泥與固定化製作之含氨氧化菌之污泥，進行氨氮亞硝酸鹽化反應之比較，實驗條件控制在溫度35℃、pH=7.8~8.0、溶氧濃度0.5、1.0、2.0、3.0、4.0，5.0 mg/L，氨氮濃度調整在600~100 mg/L範圍內，觀察氨氮、亞硝酸鹽氮，硝酸鹽氮，隨反應時間之變化情形，並由不同氨氮濃度之降解速率，分析氨氮氧化之反應動力式。 由結果可發現將氨氧化菌污泥製作成固定化細胞後，進行氨氮之亞硝酸鹽化反應，反應不受溶氧濃度之影響，且可藉由DO濃度的調整，控制亞硝酸鹽氮之產生率，操作彈性大，是一項很好改良處理技術，且符合michaelis-menten動力方程式。

Traditional denitrification technology was widely used in sewage treatment plants with low ammonia nitrogen concentration and high carbon source. The removal of ammonia nitrogen revealed low efficiency in treating wastewater with high ammonia nitrogen concentration and low C/N ratio. The advantage of ammonia nitrogen nitritation was low energy-source consumed, low carbon-source supplied and the reduced reaction time. Immobilization provided substratum that microorganisms attached on it and improved the resistance of environmental loading. Ammonia nitrogen nitritation and immobilization are both the priority of wastewater treatment. This study applied the advantages of nitritation and immobilization to analyze the reaction of nitrite. The ammonia-oxidizing bacteria were immobilized to investigate the degradation of ammonia nitrogen and the production rate of nitrite nitrogen. The reactor experiments introduced suspended populations and immobilization of ammonia-oxidizing bacteria to carry out ammonia nitrogen nitritation. The temperature was controlled at 35℃, pH was maintained from 7.8 to 8.0, the concentration was arranged from 600 to 1000 mg/L, and the DO concentration was 0.5, 1.0, 2.0, 3.0, 4.0, 5.0 mg/L. The objective of the research was to observe the variations of NH3-N, NO2-N, and NO3-N with reaction time. Furthermore, this study analyzed the reaction kinetics of ammonia oxidation from ammonia degradation rate with different concentration. From the results of the experiments, it revealed that the immobilization of ammonia-oxidizing bacteria was not influenced by DO concentration in ammonia nitrogen nitritation and the production rate of NO2-N can be regulated by DO concentration. This technology provides flexibility when removing ammonia nitrogen in wastewater and it react tally with Michaelis-Menten kinetics.