Nano-microbubble material for modifying pulverized coal in-situ consolidation and preparation method thereof

Abstract

The invention discloses a nano-microbubble material for modifying pulverized coal in-situ consolidation and a preparation method thereof. The nano-microbubble material is prepared from the following components in parts by mass: 40-60 parts of Portland cement particles, 0.5-1 part of a plant type cement foaming agent, 0.2 part of polyurethane foam stabilizer, 0.8-1.2 parts of a velocity controllingagent, 1-2 parts of sodium silicate and 1-1.5 parts of an early strength agent. The preparation method comprises the following steps: adding a high-efficiency dispersing agent into the Portland cement particles and velocity controlling agent, and grinding the mixture until the grain size is nano-grade; adding the foaming agent and the foam stabilizer into a container A, performing mixing to obtain a to-be-used foaming solution; adding the nano-grade Portland cement particles and nano-grade velocity controlling agent into a container B, adding the sodium silicate and the early strength agent into the mixture, and performing stirring and mixing at a specific environment to obtain a nano-material slurry; and finally, foaming the to-be-foamed foaming solution, mixing the foamed foaming solution with the nano-material slurry in a static mixer to prepare the nano-microbubble material. A soft coal body in a coal seam has high stability and relatively good air permeating effect after being consolidated with the nano-microbubble material, and subsequent gas extraction is facilitated.

Description

technical field [0001] The invention relates to a material for coal body consolidation and a preparation method thereof, in particular to a nano-microbubble material for in-situ consolidation modification of pulverized coal and a preparation method thereof. Background technique [0002] In the process of coal mining, with the increase of coal mining depth and gas content, gas outburst accidents often occur, especially in high gas and extremely soft coal seams, where gas disasters are more serious. At present, in order to reduce the losses caused by gas outburst accidents, protective layer mining and pre-extraction of gas are usually used to reduce the gas content in coal seams, so as to achieve the purpose of safe mining. However, in some high-gas coal mines in the south, certain conditions are required for mining protective layers, including coal seam spacing, coal seam occurrence, gas content, etc., that is to say, coal seams without outburst risk are mined first, so that ...

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Problems solved by technology

At present, our country has some measures to enhance the strength of coal body, such as the invention patent with the patent number CN201610005805.4, by opening three spatially interrelated drill holes on the coal wall, and then injecting grouting materials to strengthen the coal body. However, this method is used to prevent coal wall deviation and roof caving. It is only suitable for the coal reinforcement of the working face, and the gas permeability of the grouting material is poor, which makes it difficult for gas to penetrate the coal after the coal is consolidated. Therefore, although it can consolidate the coal body, it cannot solve the problem of drilling and injection holes

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