温和热处理对低有机质污泥厌氧消化性能的影响

Effects of Mild Thermal Pretreatment on Anaerobic Digestibility of Sludge with Low Organic Content

以高浓度低有机质污泥为研究对象,通过改变加热时间研究100℃温和热处理对其有机物溶出以及厌氧消化性能影响.结果表明通过100℃的温和热处理,污泥上清液中的有机物浓度在预处理前30 min内显著增加,30 min以后则趋于平缓.其中SCOD、蛋白质和碳水化合物在100℃热处理30 min时的溶出率分别达到10.5%、11.6%和8.2%.温和热处理不仅可以提高低有机质污泥的产气总量,而且还可以缩短产气高峰的到达时间.经100℃热处理30 min的污泥,在厌氧消化10 d时的沼气产率(以VS计)为136.0 mL·g-1,比空白对照组提高了86.0%;厌氧消化30 d后的VS降解率也由空白时的19.1%增加到33.3%.此外,实验结果还表明,100℃的温和热水解处理对厌氧消化过程中的4种关键酶(蛋白酶、乙酸激酶、磷酸转乙酰酶和辅酶F420)均有不同程度的促进作用.

The effects of mild pretreatment at temperature of 100℃ on the solubilization and anaerobic digestibility of high solid sludge with low organic content were studied with the variation of heating times.Experimental results show soluble organic concentrations in supernatant increase with the prolonging of thermal pretreatment time rapidly,and slowly after 30 min.The dissolution rates of COD,protein and carbohydrate with 30 min of thermal pretreatment at 100℃ were 10.5%,11.6% and 8.2%,respectively.Mild thermal pretreatment not only enhanced total methane yield,but also advanced the peak time of methane production.The methane production ratio with 30 min of thermal hydrolysis was 136 mL·g-1（VS） at day 10 of anaerobic digestion,with an 86% increase over the control group.VS reduction ratio after 30 days anaerobic digestion o also increased to 33.3% with 30 min of thermal pretreatment at 100℃ compared with 19.1% in control group.In addition,studies on enzymatic activity indicated the activities of four key enzymes（protease,acetokinase,phosphotransacetylase and coenzyme F420） involved in anaerobic digestion were all enhanced by mild thermal pretreatment.