Fly ash recycling method

Abstract

The invention discloses a fly ash recycling method. The method includes: grinding fly ash to a specific surface area of 300m<2> / kg-550m<2> / kg, selecting fly ash with a specific surface area of 300m<2> / kg-350m<2> / kg, 400m<2> / kg-450m<2> / kg and 500m<2> / kg-550m<2> / kg, performing compounding according to a ratio of 10%-20%:30%-40%:50%-70% to obtain modified compound fly ash; adding the obtained modified fly ash into cement clinker according to a dosage of 15%-35%, at the same time adding desulphurized gypsum accounting for 1%-3% of the mass of the fly ash, and carrying out mixing and grinding. By improving the fly ash fineness and optimizing the particle size distribution, the method improves the activity of fly ash, makes heavy use of industrial waste residue, and realizes energy saving and emission reduction.

Description

technical field [0001] The invention belongs to the technical field of building materials, and in particular relates to a method for recovering and reusing fly ash. Background technique [0002] Fly ash is one of the largest industrial wastes in my country. The annual discharge has exceeded 200 million tons, and the burden on the economy, society and environment is getting heavier. The research, development and utilization of fly ash in my country began in the 1950s, mainly focusing on the development and experimental research of cement and concrete, and has been widely used in engineering construction. However, cement mixtures and concrete admixtures have high requirements on the quality of fly ash, and at the same time, there are certain restrictions on the amount of fly ash. Only a small part of high-quality fly ash is allowed to be used in concrete structural engineering. Part of the fly ash cannot be effectively utilized in the cement system due to its coarse particles...

AI Technical Summary

Problems solved by technology

[0003] At the same time, in the "Eleventh Five-Year" environmental plan, the country has increased investment in flue gas desulfurization projects in large coal-fired enterprises, and the efficient use of desulfurization gypsum, an industrial by-product, has aroused widespread concern. If it is not handled properly, flue gas desulfurization The project only transformed the form of pollution, but did not fundamentally solve the pollution of sulfur dioxide, and piled up will be more serious