Experiment Study and Thermodynamic Analysis on Minerals Formation of Calcium-Enriched Fly Ash of Power Plant

Intends to explore the mechanism of mineral formation of calcium-enriched fly ash. Low-sulphur Yanzhou coal was selected as experimental coal, and experiments of characteristic of mineral component of calcium-enriched fly ash were conducted on two-stage poly-phase reaction setup. The collected fly ash samples were analyzed by X-ray diffraction. The results showed that crystal mineral of fly ash of Yanzhou coal mainly consisted of mullite, quartz, anorthite, hematite and other un-hydraulic mineral; with the CaO content of agglomeration coal powder gradually increasing , mineral components of fly ash begin to change; When agglomeration coal powder was added with 20% CaO , hydraulic minerals of 2CaO·SiO₂ show up; When agglomeration coal powder was added with 25% CaO,hydrauBc minerals of 2CaO·SiO₂,CaO·Al₂O₃ show up and inertia mineral disappeared In the light of thermodynamic function of state Gibbs free enthalpy, the free enthalpy variation of mineral formation reactions taking placing in process of co-production of calcium-enriched fly ash from Yanzhou coal were calculated, and the sequence of priority of mineral formation reactions were found out, and the resultants in process of co-production of calcium-enriched fly ash were investigated. The analysis conclusion accorded with experiment results of calcium-enriched fly ash from Yanzhou coal.