Browsing Research Output by Author "43ba2cde-81f4-4dea-87b4-b15db5065206"
Now showing items 1-8 of 8
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The effect of acid washing on the pyrolysis products derived from a vitrinite-rich bituminous coal
Roets, Leon; Strydom, Christien A.; Bunt, John R.; Neomagus, Hein W.J.P.; Van Niekerk, Daniel (Elsevier, 2015)Extensive characterization of the pyrolysis products, derived from raw and acid washed samples of a vitrinite-rich South African bituminous coal is reported. Pyrolysis experiments were carried out with use of a modified ... -
The effect of added minerals on the pyrolysis products derived from a vitrinite-rich demineralised South African coal
Roets, Leon; Bunt, John R.; Neomagus, Hein W.J.P.; Strydom, Christien A.; Van Niekerk, Daniel (Elsevier, 2016)A better understanding of the behaviour of the inorganic matter present in coal will assist in more cost-effective operations and more consistency in product yield and composition during thermal processing. In this study, ... -
In situ capturing and absorption of sulfur gases formed during thermal treatment of South African coals
Matjie, Ratale H.; Lesufi, Jeanett M.; Bunt, John R.; Strydom, Christien A.; Uwaoma, Romanus (ACS, 2018)The objective of this study, the first of its kind on these specific South African low-sulfur coals, was to capture H2S and SO2 produced under inert and oxidizing conditions from sulfur compounds present in the coals. The ... -
The influence of K2CO3 and KCl on H2 formation during heat treatment of an acid-treated inertinite-rich bituminous coal-char
Leeuw, Kelebogile A.; Strydom, Christien A.; Bunt, John R.; Van Niekerk, Daniel (Springer, 2016)Thermogravimetric-mass spectrometry (TG-MS) studies were conducted in order to investigate the effect of potassium carbonate (K2CO3) and potassium chloride (KCl) on the conversion and hydrogen evolution of chars derived ... -
Influence of potassium carbonate on the swelling propensity of South African large coal particles
Coetzee, Sansha; Neomagus, Hein W.J.P.; Bunt, John R.; Strydom, Christien A.; Schobert, Harold H. (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 ... -
Reactivity study of fine discard coal agglomerates
Bunt, John R.; Neomagus, Hein W.J.P.; Botha, Anke A.; Waanders, Frans B. (Elsevier, 2015)In this laboratory study thermo-gravimetric analyses were conducted to determine the influence of the addition of an alkaline metal catalyst (K2CO3 incorporated into a fine discard coal agglomerate mixture by physical ... -
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
Coetzee, Sansha; Neomagus, Hein W.J.P.; Bunt, John R.; Strydom, Christien A.; Schobert, Harold H. (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 ... -
Tailored surface energy of stainless steel plate coupons to reduce the adhesion of aluminium silicate deposit
Matjie, Ratale; Bunt, John R.; Zhang, Shuai; Zhao, Qi; Mabuza, Nhlanganiso (Elsevier, 2016)Fouling in heat exchangers not only reduces heat transfer performance significantly, but also causes considerable pressure drop, resulting in higher pumping requirements. It would be much more desirable if surfaces which ...