Method for manufacturing green and environment-friendly concrete for immobilizing heavy metals in ash residues

Abstract

The invention relates to a method for manufacturing green and environment-friendly concrete for immobilizing heavy metals in ash residues. Industrial ash residues including domestic garbage incineration power generation fly ash, slag, coal ash and the like containing heavy metal elements, metakaolin ultrafine powder (MK, specific surface area larger than or equal to 600m<2> / kg) and water-quenchedblast furnace slag ultrafine powder (BFS, specific surface area larger than or equal to 600m<2> / kg) are used as main raw materials and compounded according to a certain mass ratio, and sodium silicate, water and alkaline solution are sprayed for pelletizing to obtain a fine aggregate in the particle size smaller than 5mm and a coarse aggregate in the particle size of 5-10mm, so that immobilizationand harmlessness of heavy metals in the ash residues are realized; then, the artificial coarse and fine aggregates are proportionally compounded with MK and BFS ultrafine powder, and sodium silicate,water and alkaline solution are added to prepare concrete by stirring. The concrete avoids cement consumption and avoids consumption of natural sand and gravels as coarse and fine aggregates, and high durability is realized. In addition, the concrete is green and environment-friendly concrete with resource efficiency, energy efficiency and high durability.

Description

technical field [0001] The invention relates to a kind of industrial ash containing heavy metal elements such as fly ash, slag and fly ash which are generated by domestic waste incineration, and metakaolin superfine powder (code name MK, specific surface area ≥ 600m 2 / kg) and superfine powder of water-quenched blast furnace slag (code-named BFS, specific surface area ≥ 600m 2 / kg) as the main raw material, mixed according to a certain mass ratio, sprayed into balls with water glass, water and alkali solution, and made into fine aggregate with a particle size of <5mm and coarse aggregate with a particle size of 5-10mm, so that the ash in the slag The heavy metal is solidified and harmless. Then use this artificial coarse and fine aggregate to mix with MK and BFS superfine powder in proportion, add water glass, water and alkali solution, and stir together to make concrete. This kind of concrete does not use cement or natural sand and gravel as coarse and fine aggregates, an...

AI Technical Summary

Problems solved by technology

[0002] Domestic waste incineration power generation is the only way of domestic waste treatment recognized at home and abroad. However, the ash generated in the process of domestic waste incineration, containing heavy metal elements and radioactive substances, has not been safely and effectively treated at home and abroad so far. The harm to people has not been eliminated; every time 1,000 tons of domestic waste is incinerated to generate electricity, 100 tons of slag and 30 tons of fly ash will be produced. From a national perspective, about 500-700 million tons of domestic waste are discharged every year. All of them are used for power generation. It will produce 50-70 million tons of slag and 15-21 million tons of fly ash. The harm is so great that it is difficult to estimate