Study On Regulation Mode And Prediction Model Of Coal Ash Viscosity-Temperature Characteristics In Shendong Mining Area

The melting and fluidity of coal ash at high temperature are of great significance to the safe and stable operation of coal gasifier,the determination of operating parameters and the selection of coal.There are abundant coal resources in Shendong mining area.The problem of gasifier slagging is not smooth when the coal is used for gasification.Due to the diversity of ash and the complexity of reaction at high temperature,it is necessary to explain the influence mechanism of mixing coal and adding additives on the melting and fluidity of ash under gasification condition with theory.And accurately predicting the viscosity temperature of key temperatures of ash so as to scientifically guide the control of coal ash characteristics.In this paper,the high temperature characteristics of coal ash samples in Shendong mining area were studied by means of ash melting point tester,ash viscosity tester,infrared spectrometer and other devices,combined with thermodynamic simulation software Factsage.Taking typical BEH coal in Shendong mining area as the object,the effects of mixed HS coal on the melting characteristics and viscosity-temperature characteristics of coal ash were investigated.The melting temperature and viscosity of BEH coal ash with different proportions of flux CaO as well as the types and contents of minerals in the ash were measured.Based on 82 groups of melting temperature data of coal ash samples measured in weak reducing atmosphere,MIV algorithm was used to screen and optimize the input parameters,and a coal ash flow temperature prediction model was established based on different machine learning optimization algorithms.The relative content ratio of SiO₂ and CaO Si/Ca parameter was introduced to investigate the relationship between the chemical composition,the composite parameters and the critical temperature T_cv and the high temperature viscosity of coal ash.And the PSO-SVM prediction model of the critical temperature and high temperature viscosity of coal ash was established.The model is more accurate in predicting the measured sample data,and the prediction error is much smaller than that of the critical temperature and high-temperature viscosity predicted by the empirical formulas.