Heavy metal polluted cohesive soil remediation system

The invention provides a heavy metal polluted cohesive soil remediation system. Comprising an in-situ pulping module and an ex-situ elution module, the heavy metal contaminated soil is layered to be made into slurry capable of being pumped out and washed through in-situ operation such as foundation pit supporting, water adding soaking and rotary tillage slurrying; the ex-situ elution module is used for carrying out roller pulping on a small amount of dug surface miscellaneous fill, and the prepared slurry and the slurry pumped out in situ are sequentially subjected to particle size grading, enhanced elution, mud-water separation and wastewater treatment, so that heavy metal leaching, repairing and removing are realized; the mud-water separation unit is provided with a plurality of plate-and-frame filter presses which are connected in parallel to improve the treatment capacity of polluted soil. Through the modular design of combining in-situ pulping with ex-situ elution, the problems that cohesive soil digging