Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
J Hazard Mater. 2010 Aug 15;180(1-3):340-6. doi: 10.1016/j.jhazmat.2010.04.036. Epub 2010 Apr 24.
The hydrolysis is known to be the rate-limiting step of biological sludge anaerobic degradation. The disruptions of sludge flocs and microbial cell walls by ultrasound combined with ozone treatment (US/O(3)) were investigated in laboratory-scale experiments. The results showed that temperature, O(3) dose, US energy density and pH had a positive effect on the disintegration of sludge. The organic substrates were released into the liquor, which induced the increases of soluble chemical oxygen demand (COD(S)) and turbidity in the aqueous phase. Accordingly, the biodegradability of sludge was improved. The COD(S) increased from 1821 to 2513 mg/l after reaction for 30 min when NaHCO(3) was added, which indicated that the ozone molecule played a major role in the disintegration of waste activated sludge. The COD(S) was 2483 mg/l after 60 min O(3) treatment followed by 60 min US treatment, and it changed into 3040 mg/l after 60 min US/O(3) treatment, which proved that US/O(3) induced a synergetic effect. The pH-drop of sludge from 6.8 to 5.21 might be attributed to the increase of volatile fatty acid from 61.35 to 111.96 mg/l during the US/O(3) treatment process.
水解被认为是生物污泥厌氧降解的限速步骤。在实验室规模的实验中研究了超声与臭氧处理（US/O(3)）联合对污泥絮体和微生物细胞壁的破坏作用。结果表明，温度、臭氧剂量、US 能量密度和 pH 对污泥的解体有积极影响。有机底物释放到液体中，导致液相中可生物降解化学需氧量（COD(S)）和浊度增加。因此，污泥的生物降解性得到了提高。当添加 NaHCO(3)时，反应 30 分钟后 COD(S)从 1821 增加到 2513mg/L，表明臭氧分子在废活性污泥的解体中起主要作用。经过 60 分钟的臭氧处理和 60 分钟的 US 处理后，COD(S)为 2483mg/L，经过 60 分钟的 US/O(3)处理后，COD(S)变为 3040mg/L，这证明了 US/O(3)产生了协同作用。污泥的 pH 值从 6.8 下降到 5.21，可能是由于 US/O(3)处理过程中挥发性脂肪酸从 61.35 增加到 111.96mg/L。
