The Taichung thermal power plant, which is equipped with ten coal-fired steam generation units with total capacity of 5,500 MW in Taiwan, accounts for 20 % of the total power supply around the island with 23 million population; it is also the second largest coal-fired power station in the world. Coal is the main fuel used in the thermal power plant; during operation, it is transported on enclosed belts throughout the plant. However, spontaneous ignition of coal stockpiles increases the fire hazard for an entire power plant. Conveyor belts are widely used for coal transportation. However, there is a continuous fire risk in these facilities, and the occurrence of such an incident, in fact, is just a matter of time. Conveyor belts contain large amounts of polymeric materials; several factors can cause a fire, including frictional heat of the belt, malfunction of bearings of rollers, and coal which falls over a belt that must be properly governed to minimize the fire risk. Coal transferring facilities typically are exposed to fire risks because of two sources of ignition that need to be seriously considered. The first is the coal spontaneous ignition; the second is the conveyor belt used for coal transportation (hot burning coal, damaged bearings over-heating, roller, belt slip, and so on). This study focused on a conveyor belt fire in the Taichung thermal power plant on May 28, 2014. Based on the case analysis, the requirements and other mitigating factors affecting conveyor belt entry fires are thoroughly discussed, including fire detection systems, fire suppression devices, and cleanup of combustibles.
coal-fired steam generation units, fire hazard, coal transferring facilities, mitigating factors