Method for producing cement using desulfurized gypsum and fine coal ash

Abstract

This invention relates to a method for producing cement. This invent uses the main waste of fossil-fired power plant---desulfurized calcium sulphate and coal ash as the raw material. The charge ratio(according to weight%) is: coal ash 35-50, calcium lime 45- 53, and desulfurized calcium sulphate 5-20. Weight and charge the above coal ash, calcium lime and desulfurized calcium sulphate, and then send them to the ball grinder to grind to be 320-500 order powder, pack and store for 28-45 days, then it can obtain the product. It does not use cement clinker as raw material and does not need burning, with benefits of simple process and low cost, which makes it much qualified for mass industrial production.

Description

technical field [0001] The invention relates to a production method of building cement made from desulfurized gypsum and fly ash discharged from power plants. Background technique [0002] Desulfurization gypsum and fly ash are both by-products of thermal power plants after treatment of major pollution sources. Generally, the annual output of these two by-products in thermal power plants is more than 200,000 tons. So far, people generally use fly ash to produce fly ash bricks, and there are also people who use fly ash to produce cement. As China's CN87100904 invention patent application once disclosed a "Method for Producing Cement with High Calcium Fly Ash" , the method is to mix 5% to 30% finely ground latent hydraulic materials or pozzolanic materials into finely ground cement clinker and high-calcium fly ash, which requires a considerable amount of cement clinker to produce cement . This is the same as using high-alcohol wine to exchange low-alcohol wine. If there is n...

AI Technical Summary

Problems solved by technology

[0005] Although the strength of the cement produced by this method can meet the market's requirements for cement strength, it still needs to use other raw materials such as slag, steel slag, admixture additives and composite curing agents, which will make the formula and process complicated. The production cost is high; factors such as the aging of admixtures, additives, and composite curing agents will bring some uncertain psychological effects to users. One of the reasons to promote the app

In particular, the methods disclosed in these patent applications cannot use a large amount of desulfurization gypsum from thermal power plants, and cannot consume a large amount of secondary products generated by thermal power plants for desulfurization and environmental protection.