Heavy-metal-polluted acidic soil repairing material as well as preparation method and application thereof

Abstract

The invention discloses a heavy-metal-polluted acidic soil repairing material as well as a preparation method and application thereof. The repairing material is prepared from the following raw materials in percentage by weight: 10-20% of biomass electric power plant ash, 10-20% of slag powder, 10-30% of steel slag powder, 5-10% of fly ash and 25-50% of bentonite by uniformly mixing in a dry powder state. The preparation method comprises the following steps of: firstly, drying the raw materials until the water content is smaller than or equal to 1%; then, respectively weighing the raw materials according to the percentage by weight; and finally, uniformly stirring. The in-situ repairing of heavy-metal-polluted acidic soil is achieved by covering a layer of repairing material on the soil surface, uniformly mixing the soil surface layer with the repairing material in plowing and stirring modes, and detecting the contents of Cd, Pb, Cr, Cu, Zn, Mn, Hg, As and Ni in the repaired soil and the soil pH value after 3-6 months until meeting the requirements of the second-level soil environment quality standard in GB15618-1995.

Description

technical field [0001] The invention relates to soil in-situ repair materials in the field of agriculture and forestry, in particular to a heavy metal-polluted acidic soil repair material and its preparation method and application. Background technique [0002] Acidic soil is the general term for soil with a pH value less than 7. In my country's tropical and subtropical regions, various red or yellow acidic soils are widely distributed. The local temperature is high and the rainfall is large, with the annual rainfall mostly above 1500mm. The characteristics of high temperature, rainy season, and hot and humid seasons make the weathering and pedogenesis of the soil very strong, and the cycle of biomass is very rapid. Because the salt base in the soil is highly unsaturated, its pH value is generally maintained between 4.5 and 6. At the same time, due to the obvious accumulation of iron and aluminum oxides, the soil is sour and thin. A serious problem in acidic soils is low ...

AI Technical Summary

Problems solved by technology

However, with the continuous development of the biomass power generation industry, it has also brought about thorny issues such as the difficulty in handling solid waste from biomass power plants, especially the difficulty in resource utilization of biomass power plant ash (plant ash, rice husk ash)