Ash melting behaviour with respect to VM content of coal

Abstract

Traditional way for energy production is coal fired power plants. Ultimate product of coal fired power plants is ash. Coal ash is valuable for operations like cement production and in future it might get more importance. Ash properties changes with parent coal and operational parameters. Change in ash properties results in slagging or fouling problems inside the boiler. High temperature of combustion and low melting point of ash are the main reason of these problems. In this study 3 coal samples with moderate to high VM (volatile matter) content are observed in terms of ash melting behaviors. Lower VM content of coal resulted as lower initial ash deformation point. With the increase of VM content, increase in the slagging factor was observed. As temperature inside the boiler increases slagging is more likely to happen, since ash is molt at high temperatures. High VM content of coal is a reason for the accelerated temperature increase inside boiler. Slagging and fouling potential of the ashes of these 3 pattern coal are obtained with different indexes. Ash fusion temperature index of slagging and fouling potential resulted as “low to medium” potential for lower VM content of coal, and “high to severe” for higher VM content coals.