A high-stability colloidal foam that inhibits the oxidation and self-heating of loose coal bodies and its preparation method

Abstract

The invention discloses a high-stability colloidal foam for inhibiting the self-heating of loose coal body oxidation and a preparation method thereof. The high-stability colloidal foam is made of the following raw materials in weight percent: 58-80% water, fly ash 19-40%, air-entraining agent 0.4-0.8%, coating agent 0.2-0.6%, cross-linking agent 0.2-0.6%. The preparation method of this high-stability colloidal foam is as follows: first weigh fly ash and coating agent in proportion, add water, fully stir to obtain uniform fly ash suspension; then add air-entraining agent to the above-mentioned powder in proportion In the coal ash suspension, stir rapidly for 5-10 minutes, and produce fly ash foam through the air-entraining foaming and expansion process; finally add a cross-linking agent in proportion, and stir for 3-5 minutes to obtain a high-stability colloidal foam. The high-stability colloidal foam of the present invention has good heat-resistant stability and excellent flame-retardant performance, can maintain moisture for a long time, moisten coal bodies, and stick to loose coal bodies such as coal left in mine goafs and coal fired in coal fields. It has a good binding effect and can form a layer of film on the surface of the coal body to isolate oxygen for a long time.

Description

technical field [0001] The invention relates to the technical field of coal spontaneous combustion prevention and control, in particular to a high-stability colloidal foam for inhibiting oxidative self-heating of loose coal bodies and a preparation method thereof. Background technique [0002] Coal is the main energy source in my country. The endowment characteristics of energy resources of "rich in coal, poor in oil, and low in gas" determine that the position of coal as the main energy source in my country will not change in the short term. However, at the present stage, the mining of underground coal resources in coal mines is facing a serious threat of coal spontaneous combustion in goafs, mainly because the coal with a tendency to spontaneous combustion is in a broken and piled state. Under the condition of continuous oxygen supply, it undergoes a series of physical and chemical reactions to oxidize and accumulate heat. Spontaneous combustion at the ignition point, and ...

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Problems solved by technology

However, the existing foam materials have poor wrapping and wetting effect on loose coal bodies, short oxygen isolation time, and have very limited oxygen barrier and cooling effects on large-scale loose coal bodies in gobs.

[0004] Fly ash three-phase foam, etc. use foaming agent to modify the surface of fly ash particles, and adsorb on the gas / liquid interface during the foaming process to achieve the effect of stabilizing the foam; but the three-phase foam still has a stable time The problem of short and fast water loss, its half-life is less than 20h, and the remaining solid particles after the foam loses water will dry and pulverize, which cannot completely cover the remaining coal, so it is difficult to achieve the purpose of long-term wetting of the coal body and covering the oxygen barrier

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