Understanding how coals of different ranks interact during combustion requires linking macroscopic combustion behavior with reaction kinetics, mineral transformations, and microstructural evolution. Here, high-calorific-value bituminous coal (GY), anthracite (WY), and their 1:1 blend (GYW) were examined by thermogravimetric/derivative thermogravimetric analysis (TG-DTG), a mass-weighted non-additivity assessment, model-free isoconversional kinetics (DAEM, FWO, and Starink), X-ray diffraction (XRD), and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS). GY ignited earlier than WY (Ti = 294.12？C versus 412.95？C), consistent with its higher volatile-matter content. GYW showed small, sign-changing departures from the mass-weighted reference. With Δw = TGexp ？ TGcal, positive Δw denotes greater retained mass (apparent inhibition), whereas negative Δw denotes lower retained mass (apparent promotion); at 10？C/min, the extrema were +0.981% near 590？C and ？0.739% near 528？C. Because each condition was retained as a duplicate (n = 2) and the observed deviations (0.22% - 1.65% across the reported conditions) were within the <2% curve-reproducibility screening criterion, they are treated as descriptive non-additivity rather than statistically resolved synergy. At the same conversion, the apparent activation-energy profile of GYW generally lay between those of GY and WY and did not demonstrate a systematic lowering of the WY barrier. XRD and SEM directly support differences in mineral assemblage, surface coverage, and pore accessibility; thermal coupling, reactive-intermediate transfer, pore evolution, and Ca/AAEM-mediated catalysis remain plausible, literature-supported interpretations rather than demonstrated causal pathways. The EDS compositions are local semi-quantitative surface measurements and are not bulk residual-carbon contents. This evidence-bounded interpretation provides a more internally consistent description of GY/WY co-combustion.
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