酸水解法提取剩余污泥蛋白质的条件优化

为充分提取污水污泥中的细胞蛋白，实现污泥的增值利用，以青岛市李村河污水处理厂剩余污泥为材料，采用酸水解法提取剩余污泥中的蛋白质. 经正交试验综合考察了水解温度、水解时间、反应体系pH和固液比(污泥样品质量(g)/加水体积(mL))等因素对剩余污泥蛋白质提取率的影响. 结果表明:水解温度和反应体系pH对蛋白质提取率的影响较大；通过试验获得的提取污泥蛋白质的最优工艺条件是水解温度为121 ℃，水解时间为5 h，反应体系pH为1.25，固液比为1∶3.0.在上述条件下，剩余污泥蛋白质提取率可达62.71%，水解后的剩余残渣经干燥后测定可知，其质量相对于原污泥样品质量(干重)削减率达到30.49%. 试验证明，选用该法不仅可以达到破解剩余污泥细胞并释放蛋白质的目的，还可以使污泥减量. 

Study on Optimum Process Conditions of Extracting Sludge Protein by Acid Hydrolysis

In order to fully extract the cell protein in the sewage sludge and to realize the incremental use of the sludge, the residual sludge from Licunhe Wastewater Treatment Plant of Qingdao City was hydrolyzed by acid to extract protein. By a series of orthogonal test, the impacts of hydrolysis temperature, reaction time, pH of the reaction system, and ratio of solid(g) to liquid(mL), etc. on the extraction ratio of protein out of the sludge were examined. The result showed that the hydrolysis temperature and pH could obviously influence the protein extraction ratio. The optimal process conditions for extraction of sludge protein were as follows: temperature 121 ℃, reaction time 5 h, pH 1.25 and ratio of solid to liquid 1∶3.0. Under these conditions, the maximal protein extraction ratio was 62.71% and reductive ratio of sample could reach to 30.49%. It was indicated that after extracting protein from residual sludge, the mass of sludge could also be reduced.