Zhundong high-alkali coal has been studied a lot owing to its abundant reserve but serious ash-related issues. Oxy-fuel combustion profits the reduction of pollutant emissions and coal blending alleviates the ash-related problems practically. Nevertheless, little work if any has been carried out on oxy-fuel co-combustion of Zhundong coal, while the influences of blending on the migration of iron and alkali alkaline-earth metals have yet to be adequately understood. This study aims to illuminate the release and migration behaviors of alkali alkaline-earth metals, iron and aluminum in oxy-fuel co-combustion via a lab-scale experimental system. Experimental results showed that the yield, color, bulk, and composition of ash were greatly temperature-dependent and significantly affected by the blending ratio in oxy-fuel co-combustion. As the blending ratio was 50%, the transformation and release features of iron, sodium and calcium in the blend with combustion temperature were close to those of non-Zhundong coal. The blending of Lingxin coal into Zhundong coal could benefit the transformation from NH₄Ac-soluble calcium to H₂O-soluble form, and facilitate the transformation of HCl-soluble aluminum and iron to insoluble form. The occurrence modes of elements and the ash yield of individual coal both exerted profound impacts on the element release ratio and chemical forms within ash of the blends. The present research has potential to offer an improved knowledge on the functional mechanisms of alkali alkaline-earth metals, aluminum, and iron on ash-related issues during high-alkali coal oxy-fuel co-combustion.

准东高碱煤由于储量丰富，但与灰分相关的问题严重，因此得到了很多研究。含氧燃料燃烧有利于减少污染物排放，而掺混煤实际上可以缓解与灰有关的问题。然而，关于准东煤的氧-燃料共燃烧的工作很少，尽管还没有充分认识到混合对铁和碱土金属迁移的影响。这项研究旨在通过实验室规模的实验系统阐明氧-燃料共燃烧中碱土金属，铁和铝的释放和迁移行为。实验结果表明，灰分的产率，颜色，体积和组成在很大程度上取决于温度，并且受氧-燃料共燃烧的混合比的影响很大。当混合比为50％时，随着燃烧温度的变化，铁，钠，钙的转化释放特性与非准东煤相近。灵新煤与准东煤的混配有利于NH的转化₄将可溶于水的钙转变为可溶于H ₂ O的形式，并促进将可溶于HCl的铝和铁转变为不溶的形式。元素的发生方式和单个煤的灰分产率都对掺混物中灰分中的元素释放率和化学形式产生了深远的影响。本研究有可能提供关于碱金属，铝和铁在高碱性煤氧-燃料共燃烧过程中与灰有关的功能机理的改进知识。