Method of solidifying heavy metals in ash residue to manufacture green and environment-friendly concrete

Abstract

The invention relates to a method of solidifying heavy metals in ash residue to manufacture green and environment-friendly concrete. Fly ash, slag, coal ash and other heavy metal element-containing industrial ash residue produced by domestic garbage from incineration for power generation, metakaolin ultrafine powder (code MK, a specific surface area of greater than or equal to 600m<2>/kg) and water-quenched blast furnace slag ultrafine powder (code BFS, a specific surface area of greater than or equal to 600m<2>/kg) are adopted as the main raw materials and compounded in certain mass ratio, the compound is sprayed together with sodium silicate, water and an alkali solution into pellets to obtain fine aggregate with a particle size of less than 5mm and coarse aggregate with a particle sizeof 5-10mm, so that heavy metals in ash residue can be solidified, then the artificial coarse and fine aggregate are blended with MK and BFS ultrafine powder proportionally, and sodium silicate, waterand an alkali solution are added, and then the substances are stirred into concrete. The concrete uses neither cement nor natural sandstone as the coarse and fine aggregate, has good durability, and is a resource-saving and energy-saving green and environment-friendly concrete with 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