ABSTRACT
Spontaneous combustion is a major safety hazard in underground coal mines. Conventional technology is based on tubing bundle gas sampling system and chromatography based gas monitoring instrument, which is typically located on the ground monitor centre and suffering from long delay time, being cumbersome to maintain and inaccuracy due to possible tubing leakage. An intrinsically safe fibre optic distributed temperature sensor and interrogator for based on multimode fibre and Raman scattering principle have been developed. The fibre optic cables are laid down in the long wall ventilation tunnels and left embedded inside the goaf. The interrogator is typically installed in the underground power station with data transmitted to the ground monitor centre. Protection procedures have been developed so that the fibre optic cables have high probability of survival inside the goaf and sealed area of the underground coal mines. Early warning and location of spontaneous combustion hazards have been successfully demonstrated and fire hazard was prevented.
