超声与DNA提取酚试剂协同强化污泥蛋白质溶出

DISSOLUTION AND EXTRACTION OF PROTEIN FROM SLUDGE VIA A COMBINATION OF ULTRASOUND AND DNA EXTRACTION PHENOL REAGENT ADDITION

与常规污泥处理方式相比,热碱分解处理能得到富含蛋白质的高附加值产品,更有利于城镇污水处理厂污泥的土地利用处置。以利用热碱工艺获得的污泥混合液作为原料,以蛋白质、溶解性有机物(SCOD)、总有机碳(TOC)、总氮(TN)浓度为指标,探究超声和化学药剂处理对于污泥细胞的破坏和蛋白质的提取效果,并根据单因素控制变量实验确定最佳反应条件。结果表明:污泥最佳处理条件为超声功率480 W,时间20 min,环境初始温度38℃,环境pH为7.83和DNA提取酚试剂投加比例6%,此时蛋白质最大溶出量为861.71 mg/L,较对照组提升150%~200%;除超声时间无明显影响外,各因素对于污泥蛋白质浓度的影响均为极显著;在超声作用的基础上,外加DNA提取酚试剂协同处理可将胞内外碳水化合物和蛋白质脱附,6%化学药剂投加比例下,可将滤液中蛋白质的浓度提高至最大值861.71 mg/L。

Compared with the conventional treatment methods of sludge,the thermal alkali decomposition treatment was a preferred technology because of the high value-added protein products obtained.In this investigation,the mixture material from thermal alkali pretreatment was taken as the raw material,and variables including ultrasonic and chemical addition were investigated.Results showed that,the optimal ultrasonic power,time,initial temperature,pH and the ratio of phenol to DNA extraction reagent were 480 W,20 min,38℃,7.83 and 6%,respectively.Under this condition,the protein dissolution reached 861.71 mg/L,150%to 200%higher than the control groups.Correlation analysis suggested that except for the ultrasonic time,the effects of other factors on sludge protein concentration were extremely significant.Moreover,the addition of DNA extraction phenol reagent could desorb carbohydrates and proteins inside and outside the cell,and further increase the protein concentration to 861.71 mg/L in the filtrate with the 6%dosage.