Microwave-assisted method for compounding gangue and acetylene sludge into xonotlite fiber

Abstract

The invention provides a microwave-assisted method for compounding gangue and acetylene sludge into a xonotlite fiber. The method comprises the following steps: (1) mixing acetylene sludge with water, thereby preparing a calcium pulp; (2) alkalizing, calcining and activating gangue, uniformly mixing the activated product with water and then filtering, thereby obtaining a refined siliceous solution; (3) uniformly mixing the calcium pulp, the refined siliceous solution and a sodium hydroxide solution and performing microwave heating synthetic reaction; (4) after completing reacting, filtering a mixed slurry, thereby obtaining a filter cake and aqueous alkali; (5) washing the filter cake and drying, thereby obtaining the xonotlite fiber, and then recycling the filter cake washing effluent and the aqueous alkali into the sodium hydroxide solution. Compared with the existing compounding method, the method has the advantages of low reaction temperature, short time, simple process and mild condition; the obtained xonotlite fiber is high in purity; the phase is single and impurity-free; the degree of crystallinity is high; the performance can fully meet and even exceed the standard for light calcium silicate thermal insulation materials.

Description

technical field [0001] The invention relates to a method for synthesizing xonotlite fibers, in particular to a method for synthesizing xonotlite fibers with microwave-assisted coal gangue and carbide slag. Background technique [0002] Coal gangue is the main solid waste discharged from coal mines. Although my country has formulated a basic national policy for the utilization of coal gangue resources, the current situation of comprehensive utilization of coal gangue in my country is not optimistic. A large amount of coal gangue is still piled up and idle, which not only causes a great waste of resources, but also causes serious damage to the surrounding ecological environment. Therefore, the research on the resource utilization of coal gangue has significant significance at this stage. [0003] At present, there are many studies on the production of xonotlite directly using fly ash, alumina, silicon dioxide and sodium silicate solution as raw materials, and the technology i...

AI Technical Summary

Problems solved by technology

In the process of raw material preparation, it is necessary to use a large amount of high-quality silicon ore such as quartz sand and diatomaceous earth to co-melt with soda ash or sodium sulfate in a melting kiln, and then cool, pulverize and dissolve to make it; thus, the selection of silicon raw materials requires mining and Consume a large amount of non-renewable silicon ore resources such as quartz and diatomite; at the same time, calcareous raw materials generally need to use high-quality fuels such as coke or white coal to separately burn lime and refined milk of lime, which consumes a lot of energy and costs, and is harmful to resources and the environment. Great impact

[0008] There are also patent reports using desilication lye to prepare xonotlite, such as CN103539139 and CN103539138. The desilication lye used in these two patents is power plant waste fly ash or coal gangue and milk of lime for dynamic hydrothermal reaction to synthesize xonotlite Some breakthroughs have been made, but this method has problems such as long hydrothermal reaction time, high reaction temperature, long production cycle, high production cost, low concentration of siliceous raw materials in dealuminated lye, and low yield, and the prepared hard silicon Calcite is a mixed phase, with poor crystallinity, low purity, and low yield, so it is not suitable for mass production and industrial production

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