多孔性材料添加對於Anammox系統功能之影響

Abstract

厭氧氨氮氧化程序簡稱Anammox，為近幾十年所發展的一項新穎除氮技術，但目前在實場的應用上存在著許多缺點:(一)生長速度慢，半生期約7~12天(二)對環境要求嚴苛，因此系統不易建立。由於上述的缺點，造成了Anammox系統目前還無法普遍的應用在實場上。本研究採集迪化及內湖汙水處理廠之汙泥於實驗室內自行馴養Anammox，並利用專一性PCR來確認Anammox馴養是否成功，待馴養成功後，進行系統之菌相分析，來了解馴養之菌相分布，最後添加多孔性材料當作Anammox之載體，希望增加系統汙泥之沉降特性並藉著凝聚能力之上升進而增加形成顆粒汙泥之機會。 由本次研究之結果發現，在利用廢水處理廠汙泥所馴養之Anammox，在系統馴養後期高氨氮(490mg/L)及亞硝酸氮(700mg/L)進流之情況下，其系統除氮效率可達到99%以上，而此時馴養系統之菌群分布有大於99%可能屬於Cadidatus Kuenenia stuttgartiensis。而材料添加對於汙泥性質影響部分，在添加後系統汙泥之沉降性質有明顯的增加，汙泥容積指標由175下降為114，但材料添加卻造成系統之除氮能力大幅下降，直到添加後40天，系統除氮能力才漸漸的恢復(>95%) ，在經由real time PCR針對Anammox及其他菌群定量之結果，發現添加材料後對於系統內Anammox可能具有抑制活性或者傷害之性質，但添加材料後之環境反而助長了脫硝菌的生長，因此由實驗結果了解到多孔性鍛燒材料的添加應能增加汙泥凝聚之特性，但若應用於Anammox汙泥系統中，則可能會造成系統除氮能力之喪失。

Anaerobic ammonium oxidation process (Anammox) is a novel technology developed for nitrogen removal, especially for wastewater with high organic nitrogen content. However, limitations of its full-scale application include (1) low bacterial growth rate and long doubling time (approximately 7 to 12 day), and (2) requirement of severe operation conditions for bacterial cultivation. The objectives of this study were to establish an anammox reactor from domestic wastewater sludge and investigate the effects of porous material to bacterial aggregation in the reactor. A lab-scale reactor was used to cultivate Anammox bacteria. The results show that the Anammox reactor can achieve over 99% of nitrogen removal efficiencies with the maximum concentrations of nitrite and ammonium of 700 mg/L and 490 mg/L, respectively. The microbial community analysis of this Anammox system revealed that over 99% of bacteria were phylogenetically close to Cadidatus Kuenenia stuttgartiensis. The addition of the porous material increased the sludge settling velocity; the sludge volume index decreased from 175 to 114. However, it significantly decreased the removal efficiencies of ammonia and nitrite (<50%). The removal efficiencies slowly recovered and remained at a steady state (>95%) after 40 days of porous material addition. The results of real-time quantitative PCR using functional-gene-specific primers indicated that the addition of porous material may have adverse effects on Anammox bacteria while it may favor the growth of denitrification bacteria. The study reveals that the addition of porous material may enhance sludge settling and aggregation, however, it tends to lower nitrogen removal efficiency of Anammox system.