溶解氧对厌氧颗粒污泥活性的影响

采用血清瓶培养法,以厌氧膨胀颗粒污泥床(EGSB)反应器中接种的厌氧颗粒污泥为对象,研究了溶解氧(DO)对其产甲烷活性的影响.结果表明,水中溶解氧的升高会致使厌氧颗粒污泥的活性降低.常温22℃下,当溶解氧浓度从000mg/L上升到700mg/L时,其最大比产甲烷速率(SMA)值先后两次分别由75.9 mL·(g·d)^-1, 91.1 　mL·(g·d)^-1下降到47.6 　mL·(g·d)^-1,71.4 mL·(g·d)^-1.但温度的升高可以显著提高其活性并削弱这种变化趋势.与第1次产气实验结果相比,恒温28℃与35℃时,SMA值分别平均提高了54.0%和114.4％.进水中溶解氧的存在并不会对处理系统的运行造成不利影响,厌氧颗粒污泥对溶解氧有较强的耐受性和适应能力.因此,在工程实践中可以不考虑溶解氧因素的影响.

Impact of Dissolved Oxygen on the Activity of Anaerobic Granular Sludges

The effect of dissolved oxygen (DO) on the methanogenic activity of anaerobic granular sludges introduced into the expanded granular sludge bed (EGSB) reactor was measured in serum flasks. Results show that the specific methanogenic activity (SMA) decreases with DO increases. At 22 degrees C, the SMA drops from 75.9 mL x (g x d)(-1), 91.1 mL x (g x d)(-1) to 47.6 mL x (g x d)(-1), 71.4 mL x (g x d)(-1), respectively as DO increases from 0.00 mg/L to 7.00 mg/L. Higher temperature can weaken this trend and significantly promote SMA. As the control levels of temperature is 28 degrees C, 35 degrees C, the SMA average increases by 54.0%, 114.4% compared with that of the first gas production experiment. The study confirms that the presence of dissolved oxygen in the influent of an EGSB reactor does not constitute any evidently detrimental effect on the performance of anaerobic treatment process. Anaerobic granular sludges are demonstrated high tolerance for dissolved oxygen so that in practice this factor can be neglected.