The invention discloses a method for repairing organic-heavy
metal composite contaminated soil by
coupling chemical oxidation with
biochar enhanced microorganisms. The method comprises the following steps of: crushing to-be-remediated soil, carrying out wet screening until the particle size is less than 4mm, adjusting the soil-water ratio of a soil
aqueous solution to 1: 3-1: 5, adjusting the pH value to 5, adding a
sodium persulfate solution activated by
charcoal, carrying out leaching treatment, oxidizing organic pollutants by
sodium persulfate while leaching, and transferring heavy
metal pollutants from the soil to the
aqueous solution; after the soil and water are separated by
dehydration equipment, treating liquid by advanced oxidation equipment, further oxidizing organic pollutants,adjusting the pH value of
heavy metals to 9-10, and enabling the
heavy metals to reach the standard after coagulation and
precipitation; recycling the treated
aqueous solution for soil leaching in theprevious step; and adding the
charcoal into the separated soil, uniformly mixing, stacking, keeping ventilation, further oxidizing residual organic matters in the soil, slowly releasing the
heavy metals, and increasing the microbial activity of the soil until the contaminated soil reaches the standard.