Reactivity and structural change of coal char during steam gasification

This study is intended to clarify the relationship among the reactivity of coal char with steam, carbonaceous structural change, and ash behavior. Steam gasification of various coal chars and demineralized chars was carried out in a fixed-bed reactor at 1273 K. After gasification at certain conversion le vel, the reacted char was analyzed using Laser Raman Spectroscope (LRS), and Scanning Electron Microscope, Energy Dispersive X-ray Spectroscope (SEM/EDX) mapping. Results of SEM images and EDX-mappings revealed that novel parallel analysis of EDX-mapping and LRS-mapping were extremely effective for comprehensive evaluation of ash behavior and carbonaceous structure. As the gasification reaction proceeds, the reactivity of char was changed; existence of Si and Al seemed to suffocate the char reactivity from these parallel analyses.