Coal blends are commonly used in thermal power plants and oxy-fuel combustion also attracts great concerns recently. However, little has been done on oxy-fuel combustion of coal blends. In this paper, combustion tests are performed in a drop tube furnace for various coal blends under O₂/CO₂ mixtures, which are also reproduced numerically. Strong combustion interactions between the parent coals in a blend are observed. The ignition of the low-volatile coal is promoted due to the rapid combustion of the volatiles from the high-volatile coal. However, the char burnout of the low-volatile coal is compromised due to the rapid O₂ consumption by the large amount of volatiles. The interactions under oxy-fuel conditions are more sensitive to the excess O₂, inlet oxidizer temperature and coal particle size. 1) The increase in the excess O₂ tends to weaken the combustion interactions, in which both the ignition promotion and burnout inhibition effects on the low-volatile coal become less apparent. 2) The increase in the inlet oxidizer temperature further promotes the ignition of the low-volatile coal whereas weakens the burnout inhibition of the low-volatile coal. 3) The effects of reducing particle size on the combustion interactions are similar to those of increasing inlet oxidizer temperature. Since biomass often contains a high volatile content, the findings may shed light on the synergistic effects in oxy-fuel co-combustion of biomass and coal.

煤共混物通常用于火力发电厂，氧燃料燃烧也引起了人们的极大关注。但是，在混合煤的氧燃料燃烧方面几乎没有做过。在本文中，在滴管式炉中对O ₂ / CO ₂混合物下的各种煤混合物进行了燃烧测试，这些燃烧也以数值方式再现。观察到共混物中母煤之间强烈的燃烧相互作用。由于来自高挥发性煤的挥发物的快速燃烧，促进了低挥发性煤的点火。但是，由于大量的挥发物会迅速消耗O ₂，因此低挥发分煤的焦炭燃烧会受到影响。含氧燃料条件下的相互作用对过量的O ₂更为敏感，入口氧化剂温度和煤的粒度。1）过量O ₂的增加趋于削弱燃烧相互作用，其中对低挥发分煤的点火促进和燃尽抑制作用都变得不太明显。2）入口氧化剂温度的升高进一步促进了低挥发分煤的着火，而削弱了低挥发分煤的燃尽抑制。3）减小粒径对燃烧相互作用的影响与增加入口氧化剂温度的影响相似。由于生物质通常含有较高的挥发物含量，因此该发现可能有助于阐明生物质与煤的氧-燃料共燃烧的协同作用。