Fluidized pit backfill soil adopting contaminated soil as raw material and construction method

Abstract

The invention discloses a fluidized pit backfill soil adopting contaminated soil as a raw material and a construction method. The backfill soil is prepared from 95-105 parts of contaminated soil, 20-40 parts of a solidifying agent, 30-50 parts of water, 10-30 parts of activated carbon powder, 0-20 parts of a water reducer, 0-20 parts of quick lime, 10-30 parts of expansive soil, 0-10 parts of a shrinkage reducing agent, 0-15 parts of a retarder, 5-20 parts of nanometer silicon dioxide, 10-30 parts of nanometer titanium dioxide, 5-20 parts of nanometer zinc oxide, 5-30 parts of nanometer bentonite, 3-7 parts of perovskite and 1-4 parts of ammonia chloride. The raw materials are mixed, stirred and the like to prepare the backfill soil. The utilization rate of the contaminated soil is remarkably increased, the backfill soil and the air environment are purified, and the high flowability (capable of reaching 157), the unconfined compressive strength (capable of reaching 825 kPa) and the volume shrinkage rate (capable of reaching 2%) are achieved.

Description

technical field [0001] The invention relates to rock and soil and a construction method, in particular to a fluidized pit backfill and a construction method using polluted soil as raw material. Background technique [0002] Industrial pollutants infiltrate slowly into the soil, causing changes in the mechanical properties and chemical composition of the soil, directly affecting engineering activities or harmful to human health, animal reproduction, and plant growth, turning into polluted soil. Common treatment methods for polluted soil include chemical replacement or solidification storage yard. The former mainly extracts pollutants from the soil by electrochemical methods, which is costly and takes a long time, and is greatly affected by the types of pollutants in the soil; the latter Otherwise, a large amount of space will be occupied, and the economic benefits and environmental protection benefits are not obvious. [0003] The hundreds of millions of cubic meters of pits...

AI Technical Summary

Problems solved by technology

However, although the backfilling of mine pits does not have high requirements on the performance of materials, the demand for materials is quite large

If the traditional materials such as cement mortar and cement soil are used for backfilling, the cement consumption will be huge, which is not only costly, but also not conducive to the development of environmental protection and low-carbon economy

[0004] The Chinese patent with the publication number CN201110098060 discloses a pit backfill material and its application method, but it has the following disadvantages: (1) The cost of raw materials is high: the backfill material uses a large amount of machine-made sand, which requires manual preparation and high cost; (2) The preparation of raw materials pollutes the environment: dust that pollutes the environment will be produced during the preparation of machine-made sand; (3) The applicable area is small: machine-made sand is broken from larger stones, so it is only suitable for areas with rock distribution

Images