Soil in situ remediation, such as washing, always produces much sludge that has the characteristics of a high fine particle proportion, high moisture content, and high metal content. Problems such as high transportation costs, large land area, and the influence on landfill capacity often occur in the process of reclamation or landfill disposal. To solve the above problems, the vacuum preloading method was used to treat the sludge. The effect of this method on reducing the water content and volume of the sludge was investigated. Initial vacuum preloading (IVP) and step vacuum preloading (SVP) laboratory experiments were carried out on the sludge from the washing waste at a heavy metal soil remediation site in Shanghai. The drainage rate and settlement rate of the sludge during the experiment were recorded, and the moisture content and unconfined compressive strength (UCS) of the sludge samples after the experiment were tested and analyzed. Finally, the mechanism of uneven water content and shear strength of sludge treated by IVP and SVP were analyzed based on the grain size distribution. The results showed that the moisture content of the sludge near the prefabricated vertical drains (PVDs) decreased to 48.55%, and its volume decreased to 41.6% of the initial volume. The UCS of the sludge near the PVDs under SVP was 20.32% higher than that under IVP. The sludge treated by the vacuum preloading method can be disposed of in a landfill or other resource utilization.

中文翻译：

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真空预压处理原位洗土厂污泥的试验研究

土壤原位洗涤等修复过程中，总会产生大量具有细颗粒比例高、水分含量高、金属含量高的污泥。在开垦或填埋处理过程中，经常出现运输成本高、用地面积大、影响填埋容量等问题。为解决上述问题，采用真空预压法处理污泥。研究了该方法对降低污泥含水量和体积的影响。在上海某重金属土壤修复场地对洗涤废物产生的污泥进行了初始真空预加载（IVP）和步进真空预加载（SVP）实验室实验。记录实验过程中污泥的排水率和沉降率，并对实验后污泥样品的含水率和无侧限抗压强度（UCS）进行了测试分析。最后，基于粒度分布分析了IVP和SVP处理后污泥含水量和抗剪强度不均的机理。结果表明，预制垂直排水沟（PVDs）附近污泥的含水率下降至48.55%，体积下降至初始体积的41.6%。SVP下PVDs附近污泥的UCS比IVP下高20.32%。经真空预压法处理的污泥可填埋或其他资源化利用处理。基于粒度分布分析了IVP和SVP处理后污泥含水量和抗剪强度不均的机理。结果表明，预制垂直排水沟（PVDs）附近污泥的含水率下降至48.55%，体积下降至初始体积的41.6%。SVP下PVDs附近污泥的UCS比IVP下高20.32%。经真空预压法处理的污泥可填埋或其他资源化利用处理。基于粒度分布分析了IVP和SVP处理后污泥含水量和抗剪强度不均的机理。结果表明，预制垂直排水沟（PVDs）附近污泥的含水率下降至48.55%，体积下降至初始体积的41.6%。SVP下PVDs附近污泥的UCS比IVP下高20.32%。经真空预压法处理的污泥可填埋或其他资源化利用处理。