A self-expanding inorganic powder foam filling material for mining

Abstract

The invention relates to a self-expanding inorganic foam foaming filling material for mines. The foaming filling material comprises, by weight, 82-96 parts of a hydraulic cementing material, 1-5 partsof an air entraining agent, 1-5 parts of a reactive chemical foaming agent, 0.5-2 parts of an early strengthening agent, 1-5 parts of a thickener, 0.5-1 part of a foam stabilizer and 1-5 parts of a coagulation accelerator. The foaming filling material can be conveyed for a long distance by screw grouting after being mixed with water having an amount 2-3 times the amount of the foaming filling material, so large-water-material ratio and long-distance conveying is achieved; and the above obtained slurry is continuously foamed and expanded in the conveying process, has a large expansion ratio after being discharged from a tube orifice, and also has the characteristics of certain self-expansion, permanent consolidation, and realization of no shrinkage or collapse and stable volume of a foamedbody before being completely solidified. The product has excellent construction performance, has a good fluidity in a conveying pipeline, makes the foamed body have a small specific gravity and a high strength, is suitable for filling and sealing treatment of the top-coal caving region and corners over and below of underground coal mines, is especially suitable for filling of irregular caving spaces, and realizes the dense topping effect by means of the self-expansion of the material.

Description

technical field [0001] The invention relates to a foaming material for coal mine filling and sealing, in particular to a mine-used inorganic powder foaming filling material with self-expanding performance. Background technique [0002] Underground coal mines often use the method of filling light foam materials into the interior to control roof collapse, hole voids, gas accumulation voids in goafs, and upper and lower corner voids; rapid construction of temporary airtight walls in coal mines requires rapid filling and foaming Such materials or loess are used to seal harmful gases such as gas; underground coal mine goafs or abandoned roadways are prone to coal seam fires due to the spontaneous combustion of coal seams, and it is necessary to quickly fill, seal, seal, and heat-resistant fire-resistant materials. The amount of filling materials and fire-proof filling and sealing materials used in underground coal mines in my country is quite large. Traditional methods and measur...

AI Technical Summary

Problems solved by technology

[0005] 1) Large specific gravity, low foaming ratio, high specific gravity brings excessive pressure on the roof and other parts, it is not suitable for filling and sealing in high-risk areas, upper and lower corners, etc. in underground coal mines, and the support safety of high-risk areas is difficult to achieve

Due to the low foaming ratio and large unilateral specificity, the material consumption is large and the cost is also high

[0006] 2) The reaction time is too long, the fluidity is too large, and the foam accumulation performance is very poor. It is not suitable for filling and sealing in a specific area, or the anti-extinguishing requirements for emergency fast filling and sealing in a specific area.

After the material is filled, it is easy to collapse and lose everywhere, and it is impossible to quickly fill and seal a specific space and effectively connect the roof to achieve overall airtightness, which will lead to a series of safety hazards such as gas leakage and accumulation, or the occurrence of re-ignition in the fire zone.

However, the setting time of other existing filling materials is too fast, which is not convenient for long-distance construction, which brings greater labor costs and construction difficulties to the construction.

[0007] 3) Defects of unstable filling quality: Insufficient foam penetration, unable to connect well to the top, gaps after filling, insufficient force, difficult to achieve reliable and effective sealing, especially not suitable for high-risk areas, upper and lower corners, etc. filling treatment

Due to the artificial filling action, it is impossible to accurately ensure that the filling material has been filled to every corner, especially for the filling of irregular caving spaces, it is also difficult to achieve interference filling objectively, and the existing inorganic foam filling materials After filling, it no longer has the ability to re-foam and expand during the molding process, so it cannot expand and connect to the top by itself or even if it is connected to the top, the top is not densely connected, which leads to a series of safety hazards such as gas leakage and accumulation.

[0008] 4) The foaming agents of some existing filling materials are azo, amine or sulfonate chemical foaming agents, which cause serious environmental pollution

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