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Chemical–structural properties of South African bituminous coals: insights from wide angle XRD–carbon fraction analysis, ATR–FTIR, solid state 13C NMR, and HRTEM techniques
(Elsevier, 2015)
The chemical–structural properties of four South African bituminous coals were investigated using wide angle X-ray diffraction–carbon fraction analysis (WAXRD–CFA), attenuated total reflection Fourier transform infra-red ...
Detailed characterization of SA high mineral matter inertinite–rich coals and density fractions and effect on reaction rates with carbon dioxide: macerals, microlithotypes, carbominerites and minerals
(SAIChE, 2013)
An investigation was undertaken to determine the distribution of macerals and
minerals in South African Highveld coal deposits as well as density fractions derived from a
typical deposit. The corresponding effects on ...
Evaluating the performance and emission reductions of a coal-derived low-smoke fuel in a conventional household stove
(IEEE, 2017)
A low-smoke fuel (LSF) produced via the devolatilisation of coal lumps is proposed as an option to combat the health-damaging effects of domestic coal combustion. This study investigates the effect of the LSF particle size ...
Particle size influence on the pore development of nanopores in coal gasification chars: from micron to millimeter particles
(Elsevier, 2017)
The influence of particle size on the growth of nanopores arising from gasification of a South African
coal-char was investigated using small angle X-ray scattering. Three different char sizes (75 mm, 2 and
20 mm) were ...
Coal-derived low smoke fuel assessment through coal stove combustion testing
(Elsevier, 2017)
A study was undertaken to investigate the production of low smoke fuel from coal currently used in low-income households in South Africa. Pyrolysis of large coal lumps was studied as a possible production method, and an ...
The effect of carbon dioxide partial pressure on the gasification rate and pore development of Highveld coal chars at elevated pressures
(Elsevier, 2018)
Char structural changes occurring during gasification are normally only related to conversion and few data is published on the effect of carbon dioxide partial pressure on the extent of pore development. In this study, the ...
Mineralogy and petrology of chars produced by South African caking coals and density-separated fractions during pyrolysis and their effects on caking propensity
(ACS, 2019)
Thermochemical processes use low-rank bituminous coal to produce steam and synthetic gas. Caking coal particles can soften, swell, and coalesce in the South African boilers and fixed-bed gasifiers during pyrolysis and have ...
Influence of potassium carbonate on the swelling propensity of South African large coal particles
(ACS, 2015)
The swelling propensity of some coals may restrict their use in fixed- and fluidized-bed gasification operations, and effective reduction of swelling can widen the applicability of these coals. Extensive research has been ...
Structural and chemical modifications of typical South African biomasses during torrefaction
(Elsevier, 2016)
Torrefaction experiments were carried out for three typical South African biomass samples (softwood chips, hardwood chips and sweet sorghum bagasse) to a weight loss of 30 wt.%. During torrefaction, moisture, non-structural ...
Reduction of caking propensity in large (millimeter-sized) South African coal particles with potassium carbonate impregnation to expand fixed- and fluidized-bed gasification feedstock suitability
(ACS, 2015)
The caking propensity of coal causes challenges in combustion, gasification, and fluidized-bed applications, where this property limits coal selection. Certain gasifiers are fitted with mitigation technologies such as ...