Coal gasification gas cleanup

Determination of mineral matter and elemental composition of individual macerals in coals from Highveld mines

“…Quann and Sarofim, 1986). They may also be responsible for evolution of corrosive and polluting gases such as hydrogen sulphide, carbonyl sulphide, and sulphur oxides (Ozum et al, 1993), and the formation of ultrafine ash particles, as well as condensed metallic vapours, during coal combustion and carbon conversion processes (Zhang et al, 2006;Buhre et al, 2006;Matjie, 2008). Recognition of such elements, through either electron microprobe analysis or more conventional studies, may help to minimize the potential for corrosion, slagging, and fouling in operating combustion and gasification plants (Creelman et al, 2013), as well as the emission of gases and/or fine particulates with potential for adverse environmental impacts.…”

Sulphur capturing by an inertinite rich high ash bituminous coal during conversion in a pilot packed bed reactor

“…During coal combustion processes, sulphur is liberated from the coal structure and released mainly as SO 2 and SO 3 , whereas, during coal gasification processes, sulphur is liberated from the coal structure and released as H 2 S and COS [1,2]. Usually these gases are removed down-stream via various processes as part of gas purification steps.…”

Hot Gas Clean‐Up with Dolomites: Effect of Gas Composition on Sulfur Removal Activity

“…Specific activities of copper and cobalt-based catalysts that are used in methanol and Fischer-Tropsch fuel synthesis, respectively, significantly degrade in the presence of H 2 S. The H 2 S level is required to be lower than 1 ppmv for most applications. [1][2][3][4] Therefore, in many cases, it would be necessary to reduce the H 2 S concentration from several percentages to a few ppmv levels.…”

“…Both cooling and reheating of the syngas are thermally inefficient and expensive. [1][2][3][7][8][9] On the other hand, high-temperature desulfurization of gases by sorbents has the potential to significantly improve the thermal efficiencies of gasification and synthesis processes. [1][2][3][7][8][9] Because of their abundant availability and low costs, calcium-based sorbents such as dolomite (CaCO 3 .MgCO 3 ) or limestone (CaCO 3 ) are attractive candidate adsorbents for the clean-up of coal-derived gases at elevated temperatures ($1073-1173 K).…”

“…Therefore, these sorbents are mostly preferred for bulk H 2 S removal and an additional downstream guard bed of proper sorbent is needed for further sulfur polishing. [1,3] In this work, we report the results of experimental studies on high-temperature syngas desulfurization using dolomite. The main aim of the work is to get a better insight on dolomite-based desulfurization by investigating various possible reactions including the water-gas shift, dry reforming, steam reforming, and Boudouard reactions during sulfidation of calcined limestone.…”