No-burned brick manufacture method

Abstract

The invention discloses a method for preparing baking-free bricks, comprising the following steps: a) the raw materials which contain the following components by weight percentage are mixed uniformly: 5wt percent to 20wt percent of cement, 8wt percent to 25wt percent of aggregate, 12wt percent to 25wt percent of fly ash and 40 percent to 70 percent of waste molding sand; and b) the mixed raw materials are vibrated, pressed and maintained, thus obtaining the baking-free bricks. The baking-free bricks provided by the invention use the waste molding sand as the main raw material, as the main component of the waste molding sand is quartz sand, the surface of which has binder film and the quartz sand has uneven surface which increases the contact area between the quartz sand and other auxiliary materials, thus being beneficial to increasing the density of the baking-free bricks and increasing the strength of the baking-free bricks. The binder film becomes soft under the alkali function of the cement, thus increasing the binding strength between the quartz sand and the auxiliary materials, and when the film becomes hard, the formed closed capillary bore reduces the water absorption of the baking-free bricks, thus avoiding the freeze thawing effect of the baking-free bricks.

Description

technical field [0001] The invention relates to a method for preparing bricks, in particular to a method for preparing unburned bricks. Background technique [0002] With the rapid development of the economy, the problems of energy shortage and environmental pollution have become increasingly prominent. The development of an energy-saving and environmentally friendly green economy is the focus of economic development in all countries. Therefore, the recycling of industrial waste is also an important part of the green economy. In foundry enterprises, waste sand, as the main industrial waste product of such enterprises, has a huge output, and its disposal problem has always been a difficult problem for enterprises and governments to solve. In the prior art, the waste molding sand is generally treated by landfill or direct discharge, but since the waste molding sand contains impurities such as non-ferrous metals, the processing and discharge process will cause serious pollution...

AI Technical Summary

Problems solved by technology

[0006] However, CaO in quicklime in this method is difficult to participate in the reaction completely, so more free calcium oxide (f-CaO) will remain in the brick. When these free calcium oxide meets water to form calcium hydroxide, the volume expands. Local expansion stress is formed inside the brick, which reduces the tensile strength and flexural strength of the brick

[0007] In addition, because the amount of fly ash used in this method is too high, the porosity of unburned bricks is increased, and because fly ash has strong water absorption, too much water is filled in unburned bricks, which makes the bricks prone to freezing. Thaw damage, reducing the frost resistance of bricks

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