Construction method of separation wall for carrying out in situ separation repair on pollution site

Abstract

The invention discloses a separation wall for carrying out in situ separation repair on a pollution site and a construction method thereof. The separation wall consists of unpolluted in situ soil and bentonite, wherein the mass ratio of the in situ soil to the bentonite is 95:5 to 85:15. The construction method of the separation wall comprises the following steps of: a first step of excavating a trough body in a region on the periphery of the pollution site, wherein soil digged out from the trough body is the unpolluted in situ soil; a second step of preparing bentonite slurry; a third step of pouring the bentonite slurry into the trough body; a fourth step of preparing back filling, i.e. adding bentonite dry powder in the unpolluted in situ soil, uniformly mixing the unpolluted in situ soil and the bentonite dry powder to form the back filling; and a fifth step of filling back the back filling mixed with the bentonite into the trough body and uniformly stirring the back filling and the bentonite slurry in the trough body. Due to the adoption of the technical scheme, the construction cost of the separation wall can be reduced, the separation response time is shortened, and the separation effect is improved. Meanwhile, the construction method is simple.

Description

technical field [0001] The invention relates to the technical field of isolation and restoration of polluted sites, in particular to a construction method for an isolation wall used for in-situ isolation and repair of polluted sites. Background technique [0002] In recent years, with the demolition of a large number of chemical, steel and other factories, the problem of site pollution caused by improper handling of "three wastes" during the operation period has become increasingly apparent. The land at the original site was extensively polluted by heavy metals and organic matter and seeped into the groundwater body. The water head of the dripping liquid in the municipal solid waste landfill site exceeds the standard, the bottom liner fails, and the tailings dam is affected by rainfall, etc., which all cause the polluted liquid to invade the soil layer and spread along the direction of groundwater migration. Incomplete soil pollution remediation and sudden pollution inciden...

AI Technical Summary

Problems solved by technology

For the polluted liquid where sulfate ions, heavy metal ions and chloride ions are common, the addition of cement may aggravate the damage of the wall

At the same time, the workability of the isolation measures with cement as the main additive increases with age; it takes a long period to achieve stable workability, but the ability of the wall to resist corrosion damage during this period is low

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