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Jorge Pineres - One of the best experts on this subject based on the ideXlab platform.
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effect of temperature solvent Coal Ratio and beneficiation on conversion and product distribution from direct Coal liquefaction
Fuel, 2016Co-Authors: Juan Barraza, Edwin Coleysilva, Jorge PineresAbstract:Abstract In this paper, the effect of temperature, solvent/Coal Ratio (S/C) and Coal beneficiation (concentrates in organic matter) on the conversion and product distribution from Direct Coal Liquefaction (DCL) is studied. Coal from Cerrejon, colliery in Colombia, and a non-hydrogenated anthracene oil solvent were used. Experiments were carried out in a reactor batch of 500 ml, temperatures at 380, 400 and 420 °C for 30 min and 800 psig (5.5 MPa) hydrogen pressure, using three S/C Ratios: 2/1, 3/1 and 4/1. Coal beneficiation was conducted in a continuous flotation column. Results showed that the S/C Ratio has a positive effect on the conversion and oil content, whereas temperature has a negative effect for liquefactions of original and beneficiated Coal. Moreover, liquefactions showed increasing production of gas when temperature increases while the S/C Ratio decreases, independently of the type of Coal used. There is a negative effect using concentrate’s Coal in organic material. A marked reduction on conversion and the amount of oil is produced due to some minerals which act as catalysts – such as illite, montmorillonite, and clay minerals – were removed during the flotation process.
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Effect of temperature, solvent/Coal Ratio and beneficiation on conversion and product distribution from direct Coal liquefaction
Fuel, 2016Co-Authors: Juan Barraza, Edwin Coley-silva, Jorge PineresAbstract:Abstract In this paper, the effect of temperature, solvent/Coal Ratio (S/C) and Coal beneficiation (concentrates in organic matter) on the conversion and product distribution from Direct Coal Liquefaction (DCL) is studied. Coal from Cerrejon, colliery in Colombia, and a non-hydrogenated anthracene oil solvent were used. Experiments were carried out in a reactor batch of 500 ml, temperatures at 380, 400 and 420 °C for 30 min and 800 psig (5.5 MPa) hydrogen pressure, using three S/C Ratios: 2/1, 3/1 and 4/1. Coal beneficiation was conducted in a continuous flotation column. Results showed that the S/C Ratio has a positive effect on the conversion and oil content, whereas temperature has a negative effect for liquefactions of original and beneficiated Coal. Moreover, liquefactions showed increasing production of gas when temperature increases while the S/C Ratio decreases, independently of the type of Coal used. There is a negative effect using concentrate’s Coal in organic material. A marked reduction on conversion and the amount of oil is produced due to some minerals which act as catalysts – such as illite, montmorillonite, and clay minerals – were removed during the flotation process.
Juan Barraza - One of the best experts on this subject based on the ideXlab platform.
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effect of temperature solvent Coal Ratio and beneficiation on conversion and product distribution from direct Coal liquefaction
Fuel, 2016Co-Authors: Juan Barraza, Edwin Coleysilva, Jorge PineresAbstract:Abstract In this paper, the effect of temperature, solvent/Coal Ratio (S/C) and Coal beneficiation (concentrates in organic matter) on the conversion and product distribution from Direct Coal Liquefaction (DCL) is studied. Coal from Cerrejon, colliery in Colombia, and a non-hydrogenated anthracene oil solvent were used. Experiments were carried out in a reactor batch of 500 ml, temperatures at 380, 400 and 420 °C for 30 min and 800 psig (5.5 MPa) hydrogen pressure, using three S/C Ratios: 2/1, 3/1 and 4/1. Coal beneficiation was conducted in a continuous flotation column. Results showed that the S/C Ratio has a positive effect on the conversion and oil content, whereas temperature has a negative effect for liquefactions of original and beneficiated Coal. Moreover, liquefactions showed increasing production of gas when temperature increases while the S/C Ratio decreases, independently of the type of Coal used. There is a negative effect using concentrate’s Coal in organic material. A marked reduction on conversion and the amount of oil is produced due to some minerals which act as catalysts – such as illite, montmorillonite, and clay minerals – were removed during the flotation process.
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Effect of temperature, solvent/Coal Ratio and beneficiation on conversion and product distribution from direct Coal liquefaction
Fuel, 2016Co-Authors: Juan Barraza, Edwin Coley-silva, Jorge PineresAbstract:Abstract In this paper, the effect of temperature, solvent/Coal Ratio (S/C) and Coal beneficiation (concentrates in organic matter) on the conversion and product distribution from Direct Coal Liquefaction (DCL) is studied. Coal from Cerrejon, colliery in Colombia, and a non-hydrogenated anthracene oil solvent were used. Experiments were carried out in a reactor batch of 500 ml, temperatures at 380, 400 and 420 °C for 30 min and 800 psig (5.5 MPa) hydrogen pressure, using three S/C Ratios: 2/1, 3/1 and 4/1. Coal beneficiation was conducted in a continuous flotation column. Results showed that the S/C Ratio has a positive effect on the conversion and oil content, whereas temperature has a negative effect for liquefactions of original and beneficiated Coal. Moreover, liquefactions showed increasing production of gas when temperature increases while the S/C Ratio decreases, independently of the type of Coal used. There is a negative effect using concentrate’s Coal in organic material. A marked reduction on conversion and the amount of oil is produced due to some minerals which act as catalysts – such as illite, montmorillonite, and clay minerals – were removed during the flotation process.
Edward Furimsky - One of the best experts on this subject based on the ideXlab platform.
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Quantification of chlorine and alkali emissions from fluid bed combustion of Coal by equilibrium calculations
Fuel Processing Technology, 2003Co-Authors: Edward Furimsky, Ligang ZhengAbstract:Abstract A computer model based on the Gibbs energy minimization principle was used to identify and quantify chlorine (Cl)- and alkali-containing species formed in the temperature range from 1100 to 1200 K, air/Coal Ratio of 1.0 and 1.1 and Ca/S Ratio varying from 0 to 2.5 using low and high Cl content Coals. HCl, KCl and NaCl were the major Cl-containing volatile compounds. The amount of HCl in the vapor phase decreased and that of KCl and NaCl increased with increasing Ca/S Ratio from 0 to 2.5, whereas the increase in the air/Coal Ratio from 1.0 to 1.1 had the opposite effect. KCl and NaCl were the major, and KOH, NaOH, K 2 SO 4 and Na 2 SO 4 the minor alkali-containing species in the vapor phase of all the cases analyzed. The amount of all alkali metal-containing compounds increased with increasing Ca/S Ratio and decreased with increasing air/Coal Ratio from 1.0 to 1.1. For the low Cl Coal, the relative contribution of KOH and NaOH to the overall alkali emissions was greater than that for the high Cl Coal.
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Characterization of trace element emissions from Coal combustion by equilibrium calculations
Fuel Processing Technology, 2000Co-Authors: Edward FurimskyAbstract:Abstract A computer model based on equilibrium thermodynamics was used to characterize emissions of trace elements, such as arsenic (As), lead (Pb), cadmium (Cd), selenium (Se) and mercury (Hg), from pulverized Coal combustion (PCC) and fluidized bed combustion (FBC). For PCC, most of the As, Pb and Cd entered fly ash, whereas most of the Se and Hg were in the vapor phase. For an air/Coal Ratio=1.1, all Cd was in the solid phase, whereas for 1.0 all Cd was in the vapor phase. The same change in the air/Coal Ratio had a much less pronounced effect on partitioning of other trace elements, however, it shifted the condensation of the trace elements compounds to lower temperatures. The air/Coal Ratio influenced the type of trace element-containing compounds in the vapor phase. Chlorine (Cl) in Coal had a pronounced effect on the emissions of Hg and Pb. For FBC, more of the trace elements entered bottom ash rather than fly ash. Also, partitioning of the trace elements was influenced by the distribution of limestone and/or its products between fly ash and bottom ash. Limestone had a diluting effect on the content of trace elements in the ashes. The effect of the Ca/S Ratio on partitioning of trace elements was less pronounced than that of the air/Coal Ratio. Thus, sulfides of calcium and iron were present in the ashes when the air/Coal Ratio was lower than 1.1. A low air/Coal Ratio had an adverse effect on gaseous emissions as well.
D.h. Ahn - One of the best experts on this subject based on the ideXlab platform.
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Pressurized drop tube furnace tests of global Coal gasification characteristics
International Journal of Energy Research, 2000Co-Authors: Yongseung Shin, Sangmin Choi, D.h. AhnAbstract:Pressurized drop tube furnace (PDTF) tests were performed with an Indonesian sub-bituminous Coal while temperature, oxygen/Coal Ratio, steam/Coal Ratio and pressure were systematically varied. The tests were designed to investigate the effects of these experimental parameters on the pulverized Coal gasification characteristics at elevated pressure. The results showed that the gasification at elevated pressure is more productive than that at atmospheric pressure, considering the carbon conversion and cold gas efficiency. The oxygen/Coal Ratio at the maximum cold gas efficiency ranged between 0.5 and 0.7 g/g. Only when the temperature was sufficiently high, did the increase of steam/Coal Ratio result in the improvement of cold gas efficiency. As the pressure increased, the contribution of carbon conversion by heterogeneous reactions increased while the conversion by pyrolysis decreased. Copyright © 2000 John Wiley & Sons, Ltd.
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Experimental and numerical studies of Coal gasification with pressurized drop tube furnace
1997Co-Authors: D.h. Ahn, H.y. Park, C.y. KimAbstract:This paper describes Coal gasification studies in a PDTF reactor for IGCC. The effects of changes in reaction temperature and oxygen/Coal Ratio on the Coal gasification process have been investigated by utilizing a pressurized drop tube furnace. The objective of this study is to determine the reaction mechanisms and kinetics for gasification of imported Coals under the simulated operating conditions of commercial entrained flow gasifier. The PDTF reactor is designed to operate up to a temperature of about 1,600 C, a pressure of up to 25 bar with a wide range of inert, reducing and oxidizing atmospheres. The effects of changes in reaction temperature and oxygen/Coal Ratio on the Coal gasification process of Datong Chinese Coal have been investigated by utilizing a pressurized drop tube furnace. Pulverized Coal of under 200 mesh with a feed rate of 2g/min is fed into the reaction tube by transport nitrogen gas of 2 SLPM. Instead of using oxygen, air is used as a secondary stream of oxidant for the gasification reaction with feed rate of 4.1 to 9.5 SLPM according to the oxygen/Coal Ratio of 0.6 to 1.4, which is preheated up to the reaction temperature. The reaction temperature is changed to 1,000more » C, 1,200 C and 1,400 C respectively. However, the effects of pressure and steam/Coal Ratio on gasification were not considered in this experiment. In order to provide the proper engineering analyses for design and opeRation of a commercial Coal gasifier for IGCC, it is necessary to characterize the basic behavior of gasification of Coals at the same operating condition as the gasifier. A Pressurized Drop Tube Furnace reactor is considered as an useful facility for the such kinetic studies.« less
Haixia Zhang - One of the best experts on this subject based on the ideXlab platform.
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Gasification of bituminous Coal in a dual-bed system at different air/Coal Ratios
Energy & Fuels, 2015Co-Authors: Jiapeng Liu, Zhiping Zhu, Haibo Jiang, Haixia ZhangAbstract:Gasification experiments on bituminous Coal at different air/Coal Ratios were carried out using a newly designed combined dual-fluidized-bed pyrolysis/gasification (CDBPG) system. The effect of the air/Coal Ratio on temperature profiles, gas composition, gas heat value, tar yield, carbon conversion, and cold gas efficiency were demonstrated in this study. In the CDBPG system, only mixing the pyrolysis gas and the gasification gas to produce fuel gas is more efficient than single-bed gasification. Tar cracking was favored by an increase in the air/Coal Ratio of up to 2.4 m3/kg, and this is beneficial to improve the fuel gas value. The heat value of the product gas and the cold gas efficiency were maximized at an air/Coal Ratio of 2.1 m3/kg.