Surface Spraying for Roadways in a Coal Mine

The coal seams of this mine have a tendency toward spontaneous combustion, with a spontaneous combustion tendency grade of Ⅱ and a minimum spontaneous combustion period of 60 days. The No.3 Upper 603 working face has an average coal seam thickness of 5m, and is mined by the strike longwall retreating full-seam fully-mechanized mining method, with a total advancing strike length of 370m.
According to the working face succession plan for resources under protective pressure in the East No.6 mining area, the working face needs to be stopped for approximately 8 months. Bolt-mesh support was installed on the coal wall to prevent rib spalling in front of the working face. However, construction inevitably caused partial coal fragmentation and fractures. With reduced air velocity at the working face and prolonged direct contact between broken coal and oxygen, partial coal oxidation and spontaneous combustion could occur.
In response to the above situation, Gainike Plastic Spray Sealing Material (JPF-Ⅲ) developed by our company and its supporting application equipment were introduced. Spray sealing construction was carried out on the coal wall surface in front of the No.3 Upper 603 working face, covering 20m of the material roadway and 70m of the transportation (return air) roadway.
After applying this fire prevention and extinguishing material, a dense sealing coating formed on the coal surface of the working face and two roadways, blocking contact between coal and oxygen to prevent coal oxidation and spontaneous combustion. Meanwhile, metal supports such as metal mesh and bolts were effectively protected, preventing metal corrosion and support failure.
This construction achieved the goal of preventing coal oxidation and spontaneous combustion at the working face, ensured safe mine production, brought considerable economic and social benefits to the mine, and provided new ideas and methods for its fire prevention and control work.