添加CaCO3对煤灰熔融性影响及其机理的研究

考察了CaCO3不同添加量对三种低灰熔点煤样的软化温度（ST）的影响,揭示了CaCO3对煤灰熔融性的影响规律。同时结合X射线衍射技术及CaO—Al2O3—SiO2三元相图探讨了加入CaCO3后的煤灰熔融机理。结果表明,煤灰熔点随CaCO3加入量的提高先降后升,当煤灰CaO超过一定含量后可起到提高灰熔点的阻熔剂作用。机理表明氧化钙在加热过程中与其他成分会生成多种高含钙化合物,各物质之间会形成低温共熔化合物,造成灰熔点降低,当钙含量过高时,由于过剩氧化钙的存在,灰熔点上升。

Study of increasing coal ash fusion temperature by using CaCO3 and its mechanism

This work has studied the effect of different amount of CaCO3 on three low-fusion temperature coals’ST. It implies the rule of CaCO3’s effect on coal’s fusibility in the experiment process, with the help of the X-Ray diffraction and CaO-Al2O3-SiO2 system ternary phase diagrams can explain the ash fusion mechanism after added the CaCO3, and also discussed CaO’s impact on the coal ash’s flubility. The result shows that along with the CaO’s increasing, the coal ash fusion temperature is decreasing first,the it will be increasing finally, when CaO in coal ash preponderate over a certain content, the coal ash fusion temperature will increase.the mechanism shows that during the heating process, CaO will react with other components, this will create some compounds with high Ca content.these compounds can form eutectic compounds, so the coal ash fusion temperature will decrease, whe the content of CaO is excessive, because of the excessive CaO, the temperarure will increase.