初始pH值、ORP、振荡速率对剩余污泥厌氧酸化的影响

Influences of Different Initial pH,ORP and Shaking Rates on Anaerobic Acidification of Excess Sludge

污水处理厂产生的大量剩余污泥通过厌氧酸化能转化为挥发性脂肪酸(VFAs),可作为生物脱氮除磷的碳源加以利用。研究了不同初始p H值、氧化还原电位(ORP)和振荡速率对污泥中温厌氧产酸过程中SCOD、VFAs产量及其组分的影响,并确定各因素的最佳值。结果表明,初始p H值为6.0或8.0时能达到良好的水解和产酸效果;适当的振荡有利于加快污泥的水解和产酸速率,但其大小对丙酸形成影响不大,较高的振荡速率则有利于乙酸的积累。初始ORP对VFAs产量影响很小,但调节初始ORP有利于乙醇和戊酸的形成,不利于乙酸的积累。

Through anaerobic acidification, a large number of excess sludge from sewage treatment can be converted into volatile fatty acids （VFAs）, which can be used as carbon source for biological re- moval of nitrogen and phosphorus. The influence of different initial pH, oxidation reduction potential （ORP） and shaking rates on SCOD, VFAs yield and composition during the mesophilic anaerobic acidifi- cation of excess sludge were investigated, and the optimal value of each factor was determined. The re- sults indicated that most degradable substances in sludge were decomposed rapidly and VFAs production was maximal when the initial pH was 6.0 or 8.0. The rates of hydrolysis and acidification were speeded up with proper shaking rates, which had little effect on propionic acid, and high shaking rates could cause the accumulation of acetic acid. The initial ORP had a little influence on VFAs production. How- ever, regulating the initial ORP was beneficial to the formation of ethanol and valeric acid but not to the accumulation of acetic acid.