Insights of mineral catalytic effects of high ash coal on carbon conversion in fluidized bed Co-gasification through FTIR, XRD, XRF and FE-SEM

Abstract

This study presents the synergy of high ash coal with different biomass when blended in different ratios for co-gasification using a fluidized bed gasifier. The moisture, CO2, oxygen, hydrogen and numerous other compounds have synergetic effects on the co-gasification because of affinity to heat and prone to reaction. The mineral constituents, discrete mineral species and ion-exchangeable elements present in coal, biomass and bottom ash residue have been identified by XRD, XRF, FTIR and SEM-EDX. The catalytic effects of mineral, major oxides, halides and chlorites content on co-gasification have been assessed. The mineral (e.g. calcite, dolomite, hematite, etc.) present in the high ash coal and biomass plays a catalytic role. Other minerals (e.g. quartz, sulfide, kaolinite and phosphates) negatively influence co-gasification and product gas composition. The positive relationship of CaO, MgO and Fe2O3 with CCE, CGE and increasing heat values also supports major oxides catalytic role. The blend of press mud and high ash coal has given better results due to more Ca, K, Mg and Na elements. SEM microphotographs reveal catalytic effects at the micro-level, indicated by the extensive cracking of hydrocarbon compounds. The empirical models proposed for estimation of catalytic effects of minerals on co-gasification.