低溶解氧污泥微膨胀前后污泥硝化活性的对比研究

为了研究低溶解氧微膨胀前后污泥硝化活性的变化，采用SBR反应器，平均DO浓度为0．6mg／L-0．9mg／L，测定污泥微膨胀前后污泥氧消耗速率曲线。结果表明：发生污泥微膨胀后，活性污泥对COD的去除能力有较大的提高，而对氨氮去除能力却有一定的下降。污泥微膨胀前后的氧消耗速率曲线显示，微膨胀前活性污泥总活性为67．72mgO2／gVSS·h，其中硝化活性为43．12mgO2／gVSS·h，占其总活性的63．67％；而微膨胀后活性污泥总活性为90．49mgO2／gVSS·h，其中硝化活性为23．98mgO2／gVSS·h，占其总活性的26．51％。低DO成为微生物生长的限制性基质，污泥微膨胀的状态下，活性污泥中丝状菌成为优势菌种，而硝化细菌成为非优势菌种，污泥的总硝化活性降低。

Comparison Analysis of Sludge Nitrification Activity Before and After Micro bulking with Low Dissolved Oxygen

In order to investigate the variation of sludge nitrification activity before and after micro-bulking with low dissolved oxygen（DO）, with mean DO value of 0.6mg/L-0.9 mg/L,the sequence batch reactor （SBR） was employed to test the oxygen consumption velocity curves before and after micro-bulking. The results showed that COD removal ability increased, whereas the ammonia nitrogen removal effect was decreased with micro-bulking of sludge. The oxygen consumption velocity curves before and after micro-bulking showed that the total activity of activated sludge was 67.72 mgO2/gVSS · h before micro-bulking, of which nitrification activity was 43.12 mgO2/gVSS · h, that is, 63.67% of the total activity. And the total activity of activated sludge was 90. 49 mgO2/gVSS· h after micro-bulking, of which nitrification activity was 23. 98 mgO2/gVSS · h, that is, 26. 51% of the total activity. The low DO value was the limited substrates for microorganism growth. When activated sludge was in the state of micro-bulking, the filamentous bacteria were the dominant bacteria, whereas the nitrification bacteria were subordinate. Thus the total nitrification activity of activated sludge decreased.