A coal-friendly base gas drainage drilling hole sealing material and its application method

Abstract

The invention discloses a coalphilic gas-extracting, hole-drilling and hole-sealing material. The material comprises, by weight, 48 to 55% of cement, 8 to 10% of fly ash, 8 to 9% of calcium sulfate, 18 to 20% of calcium carbonate, 8 to 9% of silica, 0.1 to 0.2% of methyl cellulose, 1 to 2% of a water reducer, 0.8 to 1% of iron powder, 0.8 to 1% of aluminum powder and 0.2 to 0.4% of oxalic acid. The material has low viscosity and good fluidity and can efficiently penetrate into cracks in coal and rock mass surrounding a drilled hole for plugging; the material has a high expansion ratio and compressive strength and exerts high plugging effect on the drilled hole; and the material does not release heat in a reaction, has good flame retardation, good antistatic performance and strong coalphilicity, can better bond to form an integral structure and meets requirements on usage of the material in an underground coal mine.

Description

technical field [0001] The invention relates to a drilling hole sealing material for gas drainage, in particular to a coal-friendly gas drainage drilling sealing material suitable for sealing gas drainage drilling holes and their surrounding fissure air leakage channels and a method for using the same. Background technique [0002] Effective sealing of boreholes for underground gas drainage in coal mines is the key to efficient gas extraction. At present, the hole sealing methods commonly used in my country's coal mines mainly include polyurethane material sealing and cement mortar sealing. Polyurethane material is mainly mixed with various chemical slurries by manual mixing. After mixing, cotton cloth, plastic bags and other attachments are used to absorb and wrap them on the gas drainage pipeline, and send them into the drainage hole together with the gas drainage pipeline. Polyurethane sealing material has a high reaction temperature and low strength after solidification...

AI Technical Summary

Problems solved by technology

Polyurethane sealing material has high reaction temperature and low strength after solidification and hardening, which restricts its sealing effect

The cement mortar sealing process is to form a baffle device at both ends of the sealing section of the gas drainage drilling, and then inject cement mortar into it to seal the hole. It is easy to shrink after solidification and hardening, forming an air leakage channel on the crescent surface, especially the plugging effect on near-horizontal gas drainage drilling is poor, which affects the gas drainage effect

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