基于絮凝法的海港疏浚泥脱水除盐试验研究

Experimental study on dehydration and desalination of harbor dredged mud based on flocculation method

为了实现海港疏浚泥在墙材资源化利用,需解决氯离子引起的设备腐蚀和含水量高带来的运输量大的问题。研究了淤泥初始含水率、絮凝剂及pH值调节剂等因素对脱水除盐效果的影响。结果表明:初始含水率在150%~350%时,脱水率和氯离子去除率均随初始含水率的增加而提大;絮凝剂的加入会促进海港疏浚泥脱水除盐,高含水率下,絮凝剂SPFS脱水和去除氯离子能力均优于絮凝剂PAM,其中脱水率平均高26.16%,PAM不表现除氯能力,而掺入SPFS的海港疏浚泥氯离子去除率最高为25.85%,最优脱水除盐掺入比为0.0625%;絮凝剂PAM与pH值调节剂复合使用能进一步提高脱水效果,并存在最佳掺入比,但Na_(2)SO_(4)效果好于NaOH;絮凝剂PAM在碱性条件下最优脱水效果的pH值为12.2左右。

In order to realize the resource utilization of harbor dredged mud in wall materials,it is necessary to solve the problems of equipment corrosion caused by chloride ions and large transportation volume caused by high water content.The effects of initial water content of sludge,flocculant and pH regulator on dehydration and desalination were studied by dehydration rate and chloride ion removal rate.The experimental results show that when the initial water content is 150%~350%,the dehydration rate and chloride ion removal rate increase with the increase of initial water content.The addition of flocculant can promote the dehydration and desalination of harbor dredged mud.With high water content,the dehydration and chloride ion removal ability of flocculant SPFS are better than that of flocculant PAM,and the dehydration rate is 26.16% higher on average.PAM does not show the ability to remove chlorine,while the chloride ion removal rate of harbor dredged mud mixed with SPFS is 25.85%,and the optimal dehydration and desalination mixing ratio is 0.0625%.The combination of flocculant PAM and pH regulator can further improve the effect of dehydration,and there is an optimal mixing ratio,but the effect of Na_(2)SO_(4) is better than NaOH.The pH value of the optimal dehydration effect of PAM under alkaline conditions is about 12.2.