2024 Volume 17 Issue 2 Pages 105-111
To assess the risk of spontaneous ignition in the utilization of fine powdered coal within a plant, we conducted an examination of exothermic onset temperature and calorific value using High Pressure Differential Scanning Calorimetry (HP-DSC). Additionally, the induction time of the fine powdered coal was investigated using the Spontaneous Ignition Tester (SIT), and the Time to Maximum Rate at adiabatic condition (TMRad) was determined using Accelerating Rate Calorimetry (ARC). Based on the SIT and ARC results, it was observed that if there are hot spots within the fine powdered coal under adiabatic conditions, thermal runaway could occur within a few minutes due to the exothermic oxidation reaction, indicating a high risk of fire during abnormal conditions.
As a new approach to estimating the Self-Ignition Temperature (Tsi), simulations were conducted using ARC data for the oxidation temperature rising rate. The results indicated that the Tsi is estimated to be 314 K at a drum scale of about 200 L, suggesting the potential for spontaneous ignition, particularly during the summer season. We believe that the estimation of Tsi by this method can be applied to other substances prone to spontaneous ignition as well.
