Effect of MgO-based additive on the sintering behavior for slagging-fouling mitigation in Indonesian coal combustion

Abstract

Understanding phenomena in the boiler during combustion to minimize slagging fouling caused by ash deposit is important. The ash particle adhesion mainly influenced by the ash components and ash fusion temperature (AFT). Therefore, keeping the ash dry and powdery can avoid deposition problems. Fuel additives are widely used to reduce the sintering caused by alkaline compounds. This research aimed to minimize the ash deposit problem by introducing additives into coal combustion to increase the AFT. Experimental analysis was performed to determine the AFT value of 15 Indonesian Coal samples with and without additives. The ash was prepared in a cone-shaped and heated slowly in a furnace at a high temperature, then the change of cone shape is observed while the temperature is recorded. These samples were also blended with 150 ppm MgO-based additive to investigate the additive effect. Furthermore, statistic analysis was employed using the dependent t-test method to decide the significant effect of the use of MgO-based additive on the AFT value. The result showed the average AFT value of coal with additive is relatively higher than without additives. The MgO blending with coal significantly increases the AFT and can reduce ash-related problems like slagging fouling.