湖泊淤泥脱水固化复合调理剂优化及其作用机制  

Optimization and action mechanism of composite conditioner for lake sludgedewatering and solidification

作　　者：王龙涛 夏新星 WANG Longtao;XIA Xinxing(CCCC Second Harbor Engineering Co.,Ltd.,Wuhan 430040,China;CCCC Highway Bridge National Engineering Research Centre Co.,Ltd.,Wuhan 430040,China;Key Laboratory of Large-Span Bridge Construction Technology,Wuhan 430040,China;Research and Development Center of Transport Industry of Intelligent Manufacturing Technologies of Transport Infrastructure,Wuhan 430040,China)

机构地区：[1]中交第二航务工程局有限公司,湖北武汉430040 [2]中交公路长大桥建设国家工程研究中心有限公司,湖北武汉430040 [3]长大桥梁建设施工技术交通行业重点实验室,湖北武汉430040 [4]交通运输行业交通基础设施智能制造技术研发中心,湖北武汉430040

出　　处：《人民长江》2024年第1期51-59,共9页Yangtze River

基　　金：中国交通建设集团科技研发项目“水环境生态修复关键技术研究及应用推广”(2019-ZJKJ-01);国家重点研发计划项目“黄河三角洲生态修复与水沙配置技术研究及示范”(2022YFC3204305)。

摘　　要：针对湖泊淤泥脱水固化处置的难题,采用有机絮凝剂、无机絮凝剂与骨架构建剂组成的复合调理剂对湖泊淤泥进行改性调理,通过响应曲面法优化各组分的配比,并探讨复合调理剂的作用机制。结果表明:复合调理剂的最优组合为依次投加4.11 g/L聚合氯化铝(PAC)、0.18 g/L阴离子聚丙烯酰胺(APAM)和18.06 g/L低碱性淤泥固结剂(LAC);使用后污泥比阻降低87.6%,压滤脱水时间减少70.6%,尾水pH达到排放标准,脱水效率较生石灰提升5.9%。复合调理剂作用机制为PAC组分降低淤泥的Zeta电位绝对值9.5 mV,从而减少淤泥颗粒之间的静电斥力;后续加入的APAM发挥吸附-架桥的作用,聚集淤泥细颗粒为较大的絮体,利于淤泥颗粒间水分的排出;最后掺入的LAC则发挥了骨架构建剂的作用,在淤泥脱水压实过程中形成排水通道,提升了淤泥泥饼的孔隙度6.4%,进一步提升了脱水效果。研究成果可为湖泊淤泥的高效环保处置提供参考。Aiming at the difficult problem of dewatering and solidification of lake sludge,the composite conditioner formed by the combination of organic flocculant,inorganic flocculant and skeleton builder was used to modify the lake sludge.The ratio of each component was optimized by response surface method,and the mechanism of composite conditioner was discussed.The results showed that the optimal combination of composite conditioner was 4.11 g/L polyaluminium chloride(PAC),0.18 g/L anionic polyacrylamide(APAM)and 18.06 g/L low alkaline sludge consolidation agent(LAC).After using the composite conditioner,the sludge specific resistance of lake sludge was reduced by 87.6%,the pressure filtration dehydration time was reduced by 70.6%,the tail water pH reached the discharge standard,and the dehydration efficiency was 5.9%higher than that of quicklime.The mechanism of the composite conditioner was as follows:the PAC component reduced the absolute value of the Zeta potential of the sludge by 9.5 mV,thereby reducing the electrostatic repulsion between the sludge particles;the subsequent addition of APAM played the role of adsorption-bridging,and aggregated the fine particles of the sludge into larger flocs,which was conducive to the discharge of water between the sludge particles;the final doping of LAC played the role of skeleton builder,creating a drainage channel in the process of sludge dewatering and compaction,increasing the porosity of sludge cake by 6.4%,and further improving the dewatering effect.The research results can provide reference for the efficient and environmentally friendly disposal of lake sludge.

关 键 词：湖泊淤泥 脱水固化 絮凝剂 骨架构建剂 响应曲面法 

分 类 号：X705[环境科学与工程—环境工程]