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This paper attempts to relate oxygen-containing gases H 2 O, CO 2 , and CO evolved during pyrolysis of the Argonne premium coals to oxygen-containing functional groups as a function of rank. Our approach to functional group analysis of oxygen-containing species in coal has been to use a pyrolysis technique, thermogravimetric Fourier transform infrared spectroscopy (TG-FTIR), involving thermogravimetric analysis with the measurement of the gaseous decomposition products via IR detection. Under suitable heating conditions, TG-FTIR pyrolysis of a coal sample in a stream of inert gas has been shown to expel quantitatively all of the organic oxygen in the form of H 2 O, CO 2 , and CO, and consequently, this technique can be effectively applied for determining the total oxygen content. Focusing on the Argonne premium coals, which cover a wide range in rank between lignite (Ro ) 0.25) and low-volatile bituminous (Ro ) 1.68), TG-FTIR provided complex pyrolysis profiles of oxygen-containing gases, which yield information on the sources of the different peaks observed in coal as a function of rank from a chemical-structure standpoint. Deconvolution of the complex profiles was performed to assign peaks to the different sources of oxygen-containing gases. Model polymers containing various oxygen functional groups in aliphatic and/or aromatic molecular environments were also pyrolyzed by TG-FTIR in an attempt to assign peaks in the gas evolution profiles of the Argonne premium coals. Although complex evolution profiles were observed for the three oxygen-containing gas species H 2 O, CO 2 , and CO in the Argonne premium coals, the strength of the TG-FTIR technique in revealing both similarities and differences in profiles depending upon the coal rank was evident. The findings in this investigation are compared to data published on oxygen functional group analysis for the Argonne premium coals made with various analytical techniques.

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Coal injection is a common practice for coke replacement in current blast furnace (BF) operations. The amount of coal that can be injected and successfully replace large coke is determined by the extent of coal gasification, which is a function of both the combustion environment in the tuyere/ raceway region and combustibility of the injected coal. A new carbon type differentiation (CTD) technique was developed at CanmetENERGY for quantifying the amount of unburnt pulverised coal injection (PCI) residue that is carried in the furnace top gas for diagnosing the extent of injected coal gasification. This technique utilises the combustion characteristics of solid carbonaceous material generated during rapid pyrolysis and partial combustion of coal. The CTD technique developed was transferred to ArcelorMittal Dofasco and successfully implemented in the industrial environment. Using this technique, AM Dofasco established a PCI efficiency baseline for each of its three BFs, which will be used as a reference point for comparison in future trials. The capability of the CTD technique in diagnosing and understanding the effect of BF operating parameters on PCI burnout efficiency was demonstrated upon examining the effect of blast temperature decrease during a recent BF stove repair.