低温水热耦合亚铁离子活化过硫酸盐提高剩余污泥的脱水性能  

Low temperature hydrothermal coupling of ferrous ion activated persulfate to improve the dewatering performance of waste activated sludge

作　　者：孙千千 刘阵 李瑞[2] 张溪 杨明德[3] 吴玉龙 SUN Qianqian;LIU Zhen;LI Rui;ZHANG Xi;YANG Mingde;WU Yulong(College of Chemical Engineering,Xinjiang University,Urumqi 830046,Xinjiang,China;College of Materials Science and Technology,Beijing Forestry University,Beijing 100083,China;Institute of Nuclear and New Energy Technology,Tsinghua University,Beijing 100084,China)

机构地区：[1]新疆大学化工学院,新疆乌鲁木齐830046 [2]北京林业大学材料科学与技术学院,北京100083 [3]清华大学核能与新能源技术研究院,北京102201

出　　处：《化工进展》2023年第2期595-602,共8页Chemical Industry and Engineering Progress

基　　金：国家重点研发计划(2018YFC1902101)。

摘　　要：含水率高的剩余污泥给污泥的无害化处理和资源化利用带来了挑战。本文采用低温水热耦合Fe^(2+)活化过硫酸盐提高剩余污泥的脱水性能。结果表明,在80℃、Fe^(2+)/S_(2)O_(8)^(2-)的摩尔比为1.25的条件下,加入0.75mmol/g DS的Fe^(2+)和0.6mmol/g DS的S_(2)O_(8)^(2-),污泥的毛细吸水时间(CST)由397.4s±7.9s下降到18.9s±0.4s。研究发现在低温水热耦合Fe^(2+)活化过硫酸盐提高污泥脱水性能的过程中,污泥的粒径先减小后增大,胞外聚合物(EPS)被降解和絮体结构遭到破坏。在热和Fe^(2+)的共同作用下加速了过硫酸盐的分解,生成的硫酸根自由基(SO_(4)^(·-))和羟基自由基(·OH)降解了EPS,促进结合水转化为自由水,有利于污泥的固液分离。这些研究可为低温水热耦合Fe^(2+)活化过硫酸盐对污泥进行脱水处理提供了理论基础。Waste activated sludge with high moisture content challenges the harmless treatment and resource utilization of sludge.In this study,low temperature hydrothermal coupling Fe^(2+)-activated persulfate was used to improve the dewatering performance of waste activated sludge.The results showed that when 0.75mmol/g DS Fe^(2+)and 0.6mmol/g DS S_(2)O_(8)^(2-)were added at 80℃,the molar ratio of Fe^(2+)/S_(2)O_(8)^(2-)was 1.25,capillary suction time (CST) of sludge decreased from 397.4s±7.9s to 18.9s±0.4s.It was found that in the process of activating persulfate with hydrothermal coupling Fe^(2+)at low temperature to enhance the dewatering performance of sludge,the particle size of sludge first decreased and then increased,the extracellular polymer substance (EPS) was degraded,and the floc structure was damaged.The combination of heat and Fe^(2+)accelerated the decomposition of persulfates to generate sulfate radicals(SO_(4)^(·-)) and hydroxyl radicals (·OH) for oxidizing EPS,promoted the conversion of bound water into free water,and facilitated the solid-liquid separation of sludge.These studies provided a theoretical basis for dewatering sludge with low temperature hydrothermal coupling Fe^(2+)-activated persulfate.

关 键 词：剩余污泥 脱水能力 过硫酸盐 水热 活化 高级氧化工艺 

分 类 号：X703[环境科学与工程—环境工程]