产酸相反应器的过酸状态及其控制

Superacid state of acidogenic phase and controlling strategy for recovery

为了考察产酸相"过酸状态"后恢复的控制对策,试验中对降低负荷和调节碱度这两种控制措施的恢复效果进行了分析,结果表明,通过冲击负荷使产酸相反应器出现过酸状态后,将COD有机负荷从正常的15kg/(m3·d)降低到5kg/(m3·d),运行18d仍未能使反应系统的pH值得到有效恢复.当进水碱度调节在500～600mg/L范围时,系统COD有机负荷维持在9kg/(m3·d)的条件下,运行10d后过酸状态得到了基本恢复.因此,在反应系统出现过酸状态时,应在降低系统有机负荷的同时加强对进水碱度的调节,这一措施要比仅仅降低有机负荷更有利于系统的迅速恢复.过酸状态的恢复过程较缓慢,因此在冲击负荷期通过碱度的调节将系统的pH值维持在正常的范围内,从而避免"过酸状态"的发生也具有重要的意义.

In order to investigate the controlling strategy of the recovery of acidogenic phase reactor from superacid state, both the ways of cutting down the COD organic loading rate and adjusting the influent alkalinity were performed respectively in our experiments. After the acidogenic phase reactor was in the state of superacid by shock loading, the COD organic loading rate (OLR) was cut down from 15 kg/(m3·d) to 5 kg/(m3·d). However, the pH value of the reactor did not recover after 18 days operation. Acidogenic phase recovered successfully from superacid state within 10 days when the influent alkalinity was adjusted to the range of 500～600 mg/L at the COD organic loading rate of 9 kg/(m3·d). Therefore, when the reactor was in the state of superacid simultaneously, the method of decreasing OLR and adjusting influent alkalinity should be adopted, it is more efficient than only cutting down the OLR for the rapid recovery of the reactor. However, the recovery process of superacid state was relatively slow. Therefore, during the period of shock loading, the pH value of the reactor should be maintained at a normal range by adjusting influent alkalinity. It was still significant to avoid the occurrence of superacid state.