Treatment method of organic contaminated soil, purified modified soil and fluidized solidified soil

The invention relates to the technical field of solid waste recycling, and particularly discloses a treatment method of organic contaminated soil, purified modified soil and flow-state solidified soil. The treatment method of the organic contaminated soil comprises the following steps: adding a sulfite solution into the organic contaminated soil, and carrying out sulfonation reaction to obtain modified soil; the modified soil is subjected to thermal desorption treatment, and purified modified soil is obtained; in the thermal desorption treatment, the thermal desorption temperature ranges from 780 DEG C to 1000 DEG C, and the thermal desorption time ranges from 30 min to 70 min; the organic contaminated soil contains lignin, and the lignin accounts for at least 0.3% of the weight of the organic contaminated soil. According to the method, resource utilization of the organic contaminated soil can be achieved, and a dispersing agent does not need to be additionally added in the process of preparing the flow-state