低声能密度下的超声碱解剩余污泥工艺技术  

Technological Process of Ultrasonic Alkaline Hydrolysis for Excess Sludge under Low Sound Energy Density

作　　者：郭佳伟 田月臣 郭宏伟[1] GUO Jiawei;TIAN Yuechen;GUO Hongwei(Southeast University School of Power and Environment,Nanjing 210096,China)

机构地区：[1]东南大学能源与环境学院,江苏南京210096

出　　处：《净水技术》2020年第3期120-125,共6页Water Purification Technology

摘　　要：课题组前期研究表明,超声波、碱分别在污泥预处理效果方面具有一定的促进作用。同时,目前超声波预处理污泥在0.5~3 W/mL研究相对较多,0.5 W/mL以下的低声能密度以及3 W/mL以上的高声能密度下的研究还较少。在此基础上,该研究以0.19 W/mL与0.5 W/mL这两种较低的超声波声能密度环境下,使用NaOH与Ca(OH)2这两种的碱分别联合处理污泥,试验结果展现了各自相应的特征。结果表明:NaOH和Ca(OH)2分别联合超声波预处理污泥,在声能密度值为0.19 W/mL时,前者SCOD最大增加量为4871 mg/L,后者SCOD最大增加量则是3018 mg/L;提升声能密度值为0.5 W/mL后,两者SCOD最大增加量分别升至4972、4568 mg/L。该试验结果可得,对于Ca(OH)2而言,更低的声能密度0.19 W/mL下,预处理破解过程起到主导作用的是Ca^2+的絮凝搭桥作用,因而致使污泥测得的SCOD增加量相对较小;适当地加大声能密度值,Ca^2+架桥作用并未过多的影响共同作用效果。从试验效果提升的幅度以及原料成本角度看,Ca(OH)2具有一定的替代NaOH用于预处理污泥的潜力。Previous research showed that both ultrasound and alkali could promote the effect of sludge pretreatment.At the same time,there were relatively more studies on ultrasonic pretreatment of sludge in the range of 0.5~3 W/mL,and less studies on low-sound energy density below 0.5 W/mL and high-sound energy density above 3 W/mL.On this basis,the study took 0.19 W/mL and 0.5 W/mL as examples,using NaOH and Ca(OH)2 alkali to treat sludge respectively,and experimental results showed their respective characteristics.The results showed that the maximum increase of SCOD value was 4871 mg/L after NaOH combined with ultrasonic treatment,3018 mg/L after Ca(OH)2 combined with ultrasonic treatment,and 4972 mg/L after NaOH combined with ultrasonic pretreatment when acoustic energy density was 0.19 W/mL.The maximum increase of SCOD value after Ca(OH)2 combined with ultrasonic pretreatment was 3018 mg/L.The experimental results showed that for Ca(OH)2,the flocculation of Ca2+played a leading role in pretreatment cracking process at a lower acoustic energy density of 0.19 W/mL,which resulted in a relative small increase in SCOD value measured by sludge,while increasing acoustic energy density appropriately could offset bridging effect of Ca2+and start to show synergistic effects,from the extent of the enhancement of experimental results and raw materials.From the cost point of view,Ca(OH)2 had the potential to replace NaOH for pretreatment of sludge.

关 键 词：剩余污泥 超声波 碱解 联合处理 

分 类 号：TU992.3[建筑科学—市政工程]