Abstract
Half of coal reserves are low grade coal which has low calorific value. The low grade coal must be used effectively to utilize the coal resource over a long period of time. Brown coal has a lot of moisture in inside and about 2/3 of mass is moisture. When the brown coal burns for fuel of power generation, latent heat of steam evaporation causes thermal loss. For this reason, decrease of thermal efficiency occurs for brown coal utilization. Since the brown coal has low degree of carbonization, spontaneous ignition and explosion easily occur during drying process. Although we want to establish a drying technique of brown coal, the details of drying property of brown coal are not clarified and drying time of brown coal cannot be predicted exactly. In the present study, numerical model of single particle of brown coal in hot air flow was constructed and the drying property of brown coal was investigated.
