氧化预处理对污泥蛋白质提取及脱水性的影响

Effect of oxidation pretreatment on protein extraction and dewatering of sludge

为了提高污泥蛋白质的提取效率并提高其脱水性,分别采用过硫酸氢钾、过氧化钙及被Fe^(2+)活化后的过硫酸氢钾和过氧化钙预处理污泥,以考察其对污泥脱水性及蛋白质提取效率的影响并选出一种最佳的氧化预处理方式。结果表明,过硫酸氢钾和过氧化钙单独调理时,污泥脱水性有明显提高且蛋白质提取量较高。经Fe^(2+)活化后,虽然污泥比阻(FSR)比单独调理时降低50%以上,但因反应生成具有絮凝效果的Fe3+导致蛋白质提取量大幅降低。结合蛋白提取效率,发现采用0.1 g/g TSS(干物质质量)的过氧化钙单独调理效果最好,此时污泥比阻(FSR)与毛细吸水时间(tCST)分别为0.37×10^(13)m/kg、22.4s,相比原污泥比阻与毛细吸水时间分别降低78.4%和76.6%,同时蛋白质提取量高达104.52 mg/g TSS,与原污泥相比增加了80.4%。

In order to improve the efficiency of protein extraction and dewaterability of sludge,different oxidation methods were used to pre treat sludge.The effect of different oxidation pretreatment methods on the efficiency of sludge dewatering and protein extraction was investigated to select the optimal oxidation pretreatment method.And the principle of the oxidation pretreatment was described,providing theoretical guidance for protein extraction and deep dehydration technology of sludge.The influences of pretreatment with different concentrations of potassium monopersulfate and calcium peroxide(concentration ranges from0.02-0.20 g/g TSS,the gradient is 0.02)on dewatering and protein extraction efficiency of the concentrated sludge were compared.Then the concentrated sludge was pretreated with potassium monopersulfate and calcium peroxide activated respectively by Fe^(2+),in which the pH of Fe^(2+)activated calcium peroxide should be adjusted to 3.Sludge protein was extracted by heating method,and the quality of the extracted protein and the parameters of dewaterability were analyzed to select the best oxidation pretreatment method.And the results were compared with the traditional flocculant treatment then briefly describes the principle of its action by observing its microscopic structure.The results show that when the sludge is treated separately by potassium monopersulfate and calcium peroxide,the dewaterability of the sludge is significantly improved and the extracted protein content is higher.However,after Fe^(2+)activation,the specific resistance to filtration(FSR)is more than 50%lower than the potassium monopersulfate and calcium peroxide treated alone,while the protein content is greatly reduced.The reason is that the reaction product Fe3+has a flocculating effect,leading to a significant decrease in the extracted protein content.Besides,the reaction needs to adjust the pH,which results in the consumption of a large amount of acid and the increase of the economic cost of treatment.When all of these results are considered together,binding the efficiency of protein extraction and the economic cost of treatment,0.1 g/g TSS calcium peroxide treated alone has the best conditioning effect.At this time,the specific resistance to filtration(FSR)and capillary suction time(tCST)are 0.37×10^(-3)m/kg and 22.4 s respectively.Compared with the original sludge,the reduction of the specific resistance to filtration(FSR)and capillary suction time(tCST)are 78.4%and 76.6%,respectively.Meanwhile,the content of protein is up to 104.52 mg/g TSS,which is increased by 80.4%compared with the original sludge.