28 The lower the pH is and the longer the pH is at a low value,the more likely is a damaging upset.
29 For this reason, it is recommended that the pH be maintained above 6.5 for anaerobic reactors.
30 When the bicarbonate alkalinity drops below about 500 mg/L,and with the normal percentage of carbon dioxide ( approximately 38 percent ) in the reactor gas, the pH will drop close to 6.0 .
谢绝机译
參考答案:pH过大或过小都能使它（结合上文，可能是COD）处于低值，更接近于倒置破性坏
基于这种原因， PH推荐值保持在大约6.5以保证无氧呼吸
当强碱性碳酸盐滴低于大概500 mg/L时，反应气体中的二氧化碳百分比在正常值（通常是38 %）,PH值将下降至接近6.0