Coal blending is an effective method to reduce the slagging tendency. The mineral transformation within blended coal ashes has an important influence on the slagging behaviors, which have been well studied under conventional air-fuel condition. Oxy-fuel combustion is recognized as one of the most promising CO₂ reduction technologies. However, the mineral transformation within blended coal ashes in oxy-fuel condition has yet to be fully understood. This work is aimed to comprehensively study the influence of CO₂ atmosphere on Ca-containing mineral transformation behaviors during a Ca dominated coal co-firing with a Si/Al dominated coal in O₂/CO₂ condition by TG-DSC, XRD and HSC simulation. These results show that the atmosphere significantly affects on the transformation of Ca-containing mineral and the final existing form of Ca in the blended coal ashes. When the high content Ca coal is blended with the high content Al/Si coal in the O₂/CO₂ atmosphere, the CO₂ promotes the transformation of Ca into CaCO₃ and Ca under low temperature mainly exists in the form of CaCO₃ (little CaSO₄) in the blended coal ashes. CaCO₃ under high temperature is decomposed to produce highly active CaO, and CaO reacts with Al/Si to form the low melting point minerals, which may aggravate the slagging tendency. The present study can provide useful information to reduce the slagging behavior of the blended coals in the O₂/CO₂ atmosphere.

掺煤是减少结渣趋势的有效方法。掺混煤灰中的矿物转化对结渣行为具有重要影响，这在常规的空气-燃料条件下已经得到了很好的研究。含氧燃料燃烧被认为是最有希望的减少CO _2的技术之一。然而，在含氧燃料条件下混合煤灰中的矿物转化尚未完全了解。这项工作旨在全面研究在Ca占主导地位的煤与Si / Al占主导地位的煤在O ₂ / CO ₂中共烧过程中，CO ₂气氛对含Ca矿物转化行为的影响。通过TG-DSC，XRD和HSC模拟得出条件。这些结果表明，在大气显著影响上的变换的Ca的含矿物油和最终存在形式的Ca在混合煤灰。在O ₂ / CO ₂气氛中将高含量的Ca煤与高含量的Al / Si煤混合时，CO ₂促进Ca转变为CaCO _3，而低温下的Ca主要以CaCO ₃的形式存在（混合煤灰中的少量CaSO ₄）。碳酸钙₃在高温下分解产生高活性的CaO，并且CaO与Al / Si反应形成低熔点矿物，这可能会加剧结渣​​的趋势。本研究可以提供有用的信息，以减少混合气在O ₂ / CO ₂气氛中的结渣行为。