微波与酶联用对印染污泥脱水性能的影响

EFFECT OF MICROWAVE AND LYSOZYME JOINT TREATMENT ON THE DEWATERING PERFORMANCE OF PRINTING AND DYEING SLUDGE

比较微波、酶、微波与酶联用处理对印染污泥脱水性能的影响,在单因素考察的基础上,以印染污泥中毛细吸水时间(CST)、沉降曲线、扫描电镜(SEM)及EPS的三维荧光光谱等指标,通过正交试验法优选微波与酶联用预处理对破解印染污泥的最佳条件来表征污泥脱水性能,获得联合预处理最佳条件为:酶解温度40℃,加酶量0.09 g/g(TSS),酶解时间3 h,微波功率400 W,微波时间150 s。单因素实验结果表明:单独微波(400 W,180 s)和酶(0.09 g/g(TSS),40℃,4 h)处理在适当条件下均能促进污泥的破解和胞外聚合物的溶出,多糖和蛋白质的增长率分别为609%和306%,CST分别下降了12.2%和22.0%;而微波与酶联用溶出多糖和蛋白质和的增长率为1353%,CST下降了49.3%,污泥沉降性能最好。扫描电镜结果显示,微波与酶联用使污泥结构变化明显,污泥菌胶团破裂,絮体结构松散,胞内结合水转化为自由水,有利于污泥脱水。

On the basis of a single factor study,capillary water absorption time(CST),sedimentation curve,scanning electron microscope(SEM),and three-dimensional fluorescence spectra of EPS in printing and dyeing sludge was explored,and the effect of microwave,lysozyme,microwave and lysozyme joint treatment on the dewatering of printing and dyeing sludge was compared.The sludge dewatering performance was characterized by orthogonal test,and the optimal conditions for the joint treatment were:the enzymolysis temperature was 40℃,the amount of lysozyme added was 0.09 g/g(TSS),the enzymolysis time was 3 h,the microwave power was 400 W,and the microwave time was 150 s.The single factor experiment results showed that:microwave(400 W,180 s)and lysozyme(0.09 g/g(TSS),40℃,4 h)treatment could promote sludge cracking and dissolution of extracellular polymers;under those two conditions,the growth rate of dissolved polysaccharide and total proteins was 609%and 306%respectively;CST was decreased by 12.2%and 22.0%,respectively.At the same time,the joint treatment of microwave and lysozymes increased the dissolve polysaccharides and total proteins by 1353%,and decreased CST by 49.3%,and sludge sedimentation performance was the best then.SEM results showed:the combination of microwave and lysozyme made the structure of the sludge changed obviously.The sludge bacteria micelle was broken,the floc structure became loose,and the intracellular bound water was successfully converted into free water,which was beneficial to the sludge dehydration.