Application of foam–gel technology for suppressing coal spontaneous combustion in coal mines

Coal spontaneous combustion in coal mines is an extremely destructive disaster that threatens the safety of workers in the mining process. To overcome the shortcomings of existing technologies and improve the efficiency of mine fire control, a foam–gel technique was developed. The foam–gel can capture more than 90 % of water while also covering dangerous areas in all directions in goaf based on the diffusion and stacking behavior of foam. In this paper, the details of this technique are introduced, including the foam–gel formation mechanism and production process as well as the features of foam–gel technology. This technique has been applied in many coal mines, and its application at the 72,205 underground working face at San Hejian Coal Mine belonging to Xuzhou Mining Group in Jiangsu Province, China, is presented as an example. The application process is described in detail. The application results show that this new technique has a remarkable ability to suppress coal spontaneous combustion in underground coal mines.