Method for preparing lightweight calcium silicate board

Abstract

The invention discloses a method for preparing a lightweight calcium silicate board. The method comprises the following steps: (1) treating raw materials: mixing calcium sodium silicate raw materials and a dilute alkali solution to obtain mixed slurry; carrying out alkaline hydrolysis on the mixed slurry; after the hydrolysis reaction, separating the solid from liquid to obtain solid calcium silicate slag, wherein the calcium sodium silicate raw materials include one or more of fly ash, red mud, coal gangue, diatomite and bentonite; (2) preparing a mixed material, adding water and mixing uniformly, wherein the mixed material includes calcium silicate slag and reinforced fibers, and the reinforced fibers are paper fibers or cotton fibers; (3) debonding the reinforced fibers, mixing with the mixed material uniformly, and then separating solid from liquid to obtain the filter cake; (4) pressing the filter cake into a board, after formation, demolding the product, so as to obtain wet blank. The calcium silicate board prepared by using the method provided by the invention is small in density, high in strength, not liable to deform, and excellent in fireproof and thermal insulating properties; the method can realize high-valued utilization of high silica raw materials, such as fly ash, is simple and environment-friendly, and adopts a non-pressure steaming process which is economic and easy to implement.

Description

technical field [0001] The invention relates to a method for preparing a calcium silicate board, in particular to a new method for preparing a lightweight calcium silicate board, which belongs to the field of building materials. Background technique [0002] The development trend of the building materials industry is to produce light, high-strength, energy-saving and environmentally friendly building materials, use light and high-strength building materials to reduce the weight of buildings, and improve the level of mechanization and assembly of construction. As a new type of environmentally friendly building material, calcium silicate board has the characteristics of fire prevention, moisture resistance, durability, low deformation rate, and heat insulation. [0003] At present, the traditional calcium silicate board is made of siliceous materials, calcareous materials and adding reinforcing fibers and additives, and is made through mixing pulping, blanking, high-temperatur...

AI Technical Summary

Problems solved by technology

[0004] At present, most of the calcium silicate boards produced in industry are of medium and high density, with a density of 1.1g / cm 3 Above, compared with the low-density lightweight calcium silicate board, there are greater deficiencies in sound insulation, heat insulation, construction, etc.

The existing low-density calcium silicate board generally has a density of 0.6-0.9g / cm 3 Between, SiO in siliceous materials during production 2 Tobermullite crystals are produced by hydrothermal synthesis with CaO in calcareous materials, which usually requires secondary steam curing, and the cost of raw materials, energy consumption and manufacturing costs are relatively high. For such preparation methods, please refer to the patent document CN103449773A, which A disclosed lightweight calcium silicate board and its preparation method; patent document CN102584116A, which discloses an asbestos-free lightweight calcium silicate board and its manufacturing method

[0005] Patent document CN1350993A discloses a kind of manufacturing method like light calcium silicate, and this method can make density in 0.8-1.0g / cm 3 Calcium silicate plate, but it still needs high-temperature steam curing link; patent document CN103449773 discloses a low-density, high-strength, asbestos-free lightweight calcium silicate board preparation method, but the preparation method still includes light The process of sending the body of calcium silicate board into the autoclave for steaming is relatively cumbersome.

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