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Investigation of nickel supported catalysts for the upgrading of brown peat derived gasification products
03 Gaseous fuels (derived gaseous fuels) XRD, CaO peaks can be observed in raw char and CaFz peaks can be observed in demineralized char. So, it was clarified that the active species is CaO and the CaF2 cannot act as catalyst during gasification. During acid washing process, CaO reacts with HF product CaFz is the reason of the demineralized char has a lower reactivity.
02/01908
Initial operation of the PSDF transport gasifier
Smith, P. V. et al. Proceedings o f the International Conference on Fluidized Bed Combustion, 2001, (16), 428438. The Power Systems Development Facility (PSDF) is an engineering scale demonstration of advanced coal-fired power systems and hightemperature, high-pressure gas filtration systems. The PSDF was designed at sufficient scale so that advanced power systems and components could be tested in an integrated fashion to provide data for commercial scale-up. One of the two processes at the PSDF is based on the Transport reactor, which is an advanced circulating fluidized bed reactor designed to operate as either a pressurized combustor or a gasifier. The reactor operates at considerably higher circulation rates, velocities and riser densities compared to a conventional circulating bed. This results in higher throughput, better mixing, and higher mass and heat transfer. The Transport reactor was operated in combustion mode for approximately 5000 h from 1996-1999 at a typical operating conditions of 1625°F and 200 psig. The Transport reactor was reconfigured for gasification operations and began operation as a gasifier in September 1999. During the initial commissioning test runs, over 450 h of gasification was achieved with three different fuels. Gasification was carried out under conditions of 1600 to 1800°F and pressures of up to 240 psig at coal rates of 2500 to 4600 lb per h. Synthesis gas heating values of 80--120 Btu/SCF and coal carbon conversions of up to 90% have been achieved. The highest heating values were obtained at the maximum coal rate. Reactor performance was limited somewhat by an inability to maintain sufficient carbon in the circulating bed due to lower than expected char retention in the reactor loop.
02•01909 Intrinsic char gasification reactivity from TGA measurements Ren, J. et al. Proc. - Annu. Int. Pittsburgh Coal Conf., 2000, (17), 21852188. In this thesis, the kinetic of char-CO2 gasification was studied by a TGA system, and the kinetics parameters were calculated from a single TGA curve. The results show that the major factors controlling the reactivity of the char are the ranks of coal, maceral groups, pyrolysis conditions and presence of mineral matter, which acts as a catalyst during the gasification. A higher pyrolysis temperature and a longer residence time led to a decrease in reactivity. So, the severity of pyrolysis conditions decreases the reactivity of the char. TGA was used to examine the behaviour of several catalyst salts in contact with the mineral-free chars. The results show that it can make a decrease of the activation energy and make a reaction rate increase. Among the catalyst considered alkali metal is the most effective catalyst for the gasification.
02•01910 Investigation into coal gasification in an industrial jetting fluidized bed gasifier Duan, Y. et al. Proceedings o f the International Conference on Fluidized Bed Combustion, 2001, (16), 382-387. Experiments are carried out in an industrial fiuidized bed gasifier with a V-type distributor, a diameter of 0.6 m in fluidization bed, 0.8 m in freeboard and 8.0 m in height. A central airflow is jetted with a higher velocity to form an oxygen-rich zone in which the oxygen reacts with coal to release heat for endothermic gasification reaction. An annular fluidization air is blown through the distributor to fluidize the bed in a slight over the initiation fluidization to form a char-rich zone in which the reductive gasification reaction takes place. Between the central and annular region there occurs an extensive particle internal recirculation motion because of the larger air velocity difference, which plays a significant role in gas solid mixing, heat and mass transfer, and in maintaining an even temperature in the gasifier. Fly-ash recycle technology is adopted to reduce the char loss and improve the efficiency of coal utilization. Gas samples are gathered at different height along the freeboard up to the exit and are analysed. The gasifier runs with different fluidization airflow rate, different central airflow rate, different coal feeding rate and different water steam flow rate. The effects of those parameters on the gasification of coal, the components of the gas and the gas heating value are investigated. The fluidization characteristic of the V-type distributor is also conducted. The results have provided guidance for the real run of the gasifier and its enlargement design.
02/01911 Investigation of nickel supported catalysts for the upgrading of brown peat derived gasification products Sutton, D. el al. Bioresource Technology, 2001, 80, (2), l l 1-116.
A gasification test rig was designed in which peat was gasified under nitrogen over a temperature range 25-550°C at 5°C min i The gasification unit resulted in 35.5 wt% of the carbon present in the peat being converted to a volatile fraction. The volatile fraction was transferred to a secondary catalytic reforming reactor at 800°C. The thermal effect of the second reactor resulted in an increase in the CO, CO2 and CHa content of the volatile fraction, a syngas ratio of 0.75 and a higher heating value (HHV) of 26.5 MJ kg 1. Several nickelsupported catalysts were investigated with the intention that they should give an increase in the conversion of the condensable hydrocarbons in the volatile fraction to CO, COz and CH4 and a resultant gas stream suitable for use in an integrated gasification combined cycle plant (IGCC) (i.e. syngas ratio 2:1, low methane content and better HHV). Alumina-supported nickel catalysts investigated gave the highest activities and co-precipitated Ni/AI catalyst were most active. A Ni/AI 3:17 catalyst increased the conversion of the hydrocarbons to 91.5%, gave a syngas ratio of 1.81:1, increased the HHV by a factor of 5.3 and completely eliminated methane from the gas stream.
02/01912 Kinetics of gasification in a fixed bed reactor with steam-oxygen mixtures Conradie, M. and Prinsloo, F. F. Proc. - Annu. Int. Pittsburgh Coal Conf., 2000, (17), 1051-1060. The kinetics of steam/Oz gasification of coarse high-ash sub-bituminous South-African coal particles was studied in a vertical fixed bed reactor. The gasifier, which operated at atmospheric pressure, was loaded with char produced by the coal. The main operating variables studied were space velocity, gasifier bed temperature and particle size distribution. The majority of the reactions were studied under conditions of chemical rate control alone. The data were interpreted in terms of various mechanistic models. It was concluded that the difference in diffusivity between oxygen and steam in the micropores has a major influence on the shape of the bum-off profile and that the random pore model described the experimental data best. Experimental kinetic equations for the coal were also detected.
02/01913 Manufacture of dimethyl ether using hydrogen separated from coal mine gas-derived synthesis gas Inoue, N. and Hiramatsu, T. Jpn. Kokai Tokkyo Koho JP 2001 342,161 (CI. C07C43/04), 11 Dec 2001, Appl. 2000/164,239, 1 Jun 2000. 4. (In Japanese) Me20 is manufactured using H2 separated from gas which is manufactured by (1) reforming coal mine gas by adding steam and 02 and (2) adding steam to the resulting synthesis gas for shift reaction.
02/01914 Manufacture of synthesis gas for gasoline, gas oil, and kerosene manufacturing Iijima, M. and Kobayashi, K. Jpn. Kokai Tokkyo Koho JP 2001 342,003 (CI. C01B3/34), 11 Dec 2001, Appl. 2000/160,510, 30 May 2000.22. (In Japanese) CO- and H-containing gases for manufactured of gasoline, gas oil, and kerosene by Fischer-Tropsch reaction are manufactured by supplying steam-containing natural gas to a reformer, recovering COz from waste combustion gases from a heater for the reformer, and supplying COz to the upper flow of the reformer to adjust the molar ratio of H/CO 1-2.5. The method enables manufacture of CO- and H-containing gases at the desired ratio by supply of COz in the plant.
02/01915 Mathematical modeling and simulation of bubbling fluidized bed gasifiers Hamel, S. and Krumm, W. Powder Technology, 2001, 120, (1-2), 105112. A mathematical model for simulation of gasification processes of solid fuels in atmospheric or pressurized bubbling fluidized beds incorporating bed and freeboard hydrodynamics, fuel drying and devolatilization, and chemical reaction kinetics is presented. The model was used to simulate four bubbling fluidized bed gasifiers, described in literature, of different scales from atmospheric laboratory scale up to pressurized compression scale, processing brown coal, peat and sawdust. The gasifiers were operated within a wide range of parameters using air, air/steam or oxygen/steam as gasification agent, operating with or without re-circulation of fines at operating pressures up to 2.5 MPa. The simulation results for overall carbon conversion, temperature and concentrations of gaseous species agree sufficiently well with published experimental data.
02/01916
Method for the gasification of coal
Katayama, Y. Eur. Pat. Appl. EP 1,154,008 (CI. C10J3/16), 14 Nov 2001, JP Appl. 2000/136,268, 9 May 2000. 11. A method of the gasification of coal using oxygen and steam is provided wherein the coal is gasified at from 1000 to 2500 ° and a pressure of from 1 to 100 kg/cm z using oxygen generated by electrolysing water and steam having a temperature of from 300 to 600 ° attained by heat
Fuel and Energy Abstracts
July 2002 249
02/01908
Initial operation of the PSDF transport gasifier
Smith, P. V. et al. Proceedings o f the International Conference on Fluidized Bed Combustion, 2001, (16), 428438. The Power Systems Development Facility (PSDF) is an engineering scale demonstration of advanced coal-fired power systems and hightemperature, high-pressure gas filtration systems. The PSDF was designed at sufficient scale so that advanced power systems and components could be tested in an integrated fashion to provide data for commercial scale-up. One of the two processes at the PSDF is based on the Transport reactor, which is an advanced circulating fluidized bed reactor designed to operate as either a pressurized combustor or a gasifier. The reactor operates at considerably higher circulation rates, velocities and riser densities compared to a conventional circulating bed. This results in higher throughput, better mixing, and higher mass and heat transfer. The Transport reactor was operated in combustion mode for approximately 5000 h from 1996-1999 at a typical operating conditions of 1625°F and 200 psig. The Transport reactor was reconfigured for gasification operations and began operation as a gasifier in September 1999. During the initial commissioning test runs, over 450 h of gasification was achieved with three different fuels. Gasification was carried out under conditions of 1600 to 1800°F and pressures of up to 240 psig at coal rates of 2500 to 4600 lb per h. Synthesis gas heating values of 80--120 Btu/SCF and coal carbon conversions of up to 90% have been achieved. The highest heating values were obtained at the maximum coal rate. Reactor performance was limited somewhat by an inability to maintain sufficient carbon in the circulating bed due to lower than expected char retention in the reactor loop.
02•01909 Intrinsic char gasification reactivity from TGA measurements Ren, J. et al. Proc. - Annu. Int. Pittsburgh Coal Conf., 2000, (17), 21852188. In this thesis, the kinetic of char-CO2 gasification was studied by a TGA system, and the kinetics parameters were calculated from a single TGA curve. The results show that the major factors controlling the reactivity of the char are the ranks of coal, maceral groups, pyrolysis conditions and presence of mineral matter, which acts as a catalyst during the gasification. A higher pyrolysis temperature and a longer residence time led to a decrease in reactivity. So, the severity of pyrolysis conditions decreases the reactivity of the char. TGA was used to examine the behaviour of several catalyst salts in contact with the mineral-free chars. The results show that it can make a decrease of the activation energy and make a reaction rate increase. Among the catalyst considered alkali metal is the most effective catalyst for the gasification.
02•01910 Investigation into coal gasification in an industrial jetting fluidized bed gasifier Duan, Y. et al. Proceedings o f the International Conference on Fluidized Bed Combustion, 2001, (16), 382-387. Experiments are carried out in an industrial fiuidized bed gasifier with a V-type distributor, a diameter of 0.6 m in fluidization bed, 0.8 m in freeboard and 8.0 m in height. A central airflow is jetted with a higher velocity to form an oxygen-rich zone in which the oxygen reacts with coal to release heat for endothermic gasification reaction. An annular fluidization air is blown through the distributor to fluidize the bed in a slight over the initiation fluidization to form a char-rich zone in which the reductive gasification reaction takes place. Between the central and annular region there occurs an extensive particle internal recirculation motion because of the larger air velocity difference, which plays a significant role in gas solid mixing, heat and mass transfer, and in maintaining an even temperature in the gasifier. Fly-ash recycle technology is adopted to reduce the char loss and improve the efficiency of coal utilization. Gas samples are gathered at different height along the freeboard up to the exit and are analysed. The gasifier runs with different fluidization airflow rate, different central airflow rate, different coal feeding rate and different water steam flow rate. The effects of those parameters on the gasification of coal, the components of the gas and the gas heating value are investigated. The fluidization characteristic of the V-type distributor is also conducted. The results have provided guidance for the real run of the gasifier and its enlargement design.
02/01911 Investigation of nickel supported catalysts for the upgrading of brown peat derived gasification products Sutton, D. el al. Bioresource Technology, 2001, 80, (2), l l 1-116.
A gasification test rig was designed in which peat was gasified under nitrogen over a temperature range 25-550°C at 5°C min i The gasification unit resulted in 35.5 wt% of the carbon present in the peat being converted to a volatile fraction. The volatile fraction was transferred to a secondary catalytic reforming reactor at 800°C. The thermal effect of the second reactor resulted in an increase in the CO, CO2 and CHa content of the volatile fraction, a syngas ratio of 0.75 and a higher heating value (HHV) of 26.5 MJ kg 1. Several nickelsupported catalysts were investigated with the intention that they should give an increase in the conversion of the condensable hydrocarbons in the volatile fraction to CO, COz and CH4 and a resultant gas stream suitable for use in an integrated gasification combined cycle plant (IGCC) (i.e. syngas ratio 2:1, low methane content and better HHV). Alumina-supported nickel catalysts investigated gave the highest activities and co-precipitated Ni/AI catalyst were most active. A Ni/AI 3:17 catalyst increased the conversion of the hydrocarbons to 91.5%, gave a syngas ratio of 1.81:1, increased the HHV by a factor of 5.3 and completely eliminated methane from the gas stream.
02/01912 Kinetics of gasification in a fixed bed reactor with steam-oxygen mixtures Conradie, M. and Prinsloo, F. F. Proc. - Annu. Int. Pittsburgh Coal Conf., 2000, (17), 1051-1060. The kinetics of steam/Oz gasification of coarse high-ash sub-bituminous South-African coal particles was studied in a vertical fixed bed reactor. The gasifier, which operated at atmospheric pressure, was loaded with char produced by the coal. The main operating variables studied were space velocity, gasifier bed temperature and particle size distribution. The majority of the reactions were studied under conditions of chemical rate control alone. The data were interpreted in terms of various mechanistic models. It was concluded that the difference in diffusivity between oxygen and steam in the micropores has a major influence on the shape of the bum-off profile and that the random pore model described the experimental data best. Experimental kinetic equations for the coal were also detected.
02/01913 Manufacture of dimethyl ether using hydrogen separated from coal mine gas-derived synthesis gas Inoue, N. and Hiramatsu, T. Jpn. Kokai Tokkyo Koho JP 2001 342,161 (CI. C07C43/04), 11 Dec 2001, Appl. 2000/164,239, 1 Jun 2000. 4. (In Japanese) Me20 is manufactured using H2 separated from gas which is manufactured by (1) reforming coal mine gas by adding steam and 02 and (2) adding steam to the resulting synthesis gas for shift reaction.
02/01914 Manufacture of synthesis gas for gasoline, gas oil, and kerosene manufacturing Iijima, M. and Kobayashi, K. Jpn. Kokai Tokkyo Koho JP 2001 342,003 (CI. C01B3/34), 11 Dec 2001, Appl. 2000/160,510, 30 May 2000.22. (In Japanese) CO- and H-containing gases for manufactured of gasoline, gas oil, and kerosene by Fischer-Tropsch reaction are manufactured by supplying steam-containing natural gas to a reformer, recovering COz from waste combustion gases from a heater for the reformer, and supplying COz to the upper flow of the reformer to adjust the molar ratio of H/CO 1-2.5. The method enables manufacture of CO- and H-containing gases at the desired ratio by supply of COz in the plant.
02/01915 Mathematical modeling and simulation of bubbling fluidized bed gasifiers Hamel, S. and Krumm, W. Powder Technology, 2001, 120, (1-2), 105112. A mathematical model for simulation of gasification processes of solid fuels in atmospheric or pressurized bubbling fluidized beds incorporating bed and freeboard hydrodynamics, fuel drying and devolatilization, and chemical reaction kinetics is presented. The model was used to simulate four bubbling fluidized bed gasifiers, described in literature, of different scales from atmospheric laboratory scale up to pressurized compression scale, processing brown coal, peat and sawdust. The gasifiers were operated within a wide range of parameters using air, air/steam or oxygen/steam as gasification agent, operating with or without re-circulation of fines at operating pressures up to 2.5 MPa. The simulation results for overall carbon conversion, temperature and concentrations of gaseous species agree sufficiently well with published experimental data.
02/01916
Method for the gasification of coal
Katayama, Y. Eur. Pat. Appl. EP 1,154,008 (CI. C10J3/16), 14 Nov 2001, JP Appl. 2000/136,268, 9 May 2000. 11. A method of the gasification of coal using oxygen and steam is provided wherein the coal is gasified at from 1000 to 2500 ° and a pressure of from 1 to 100 kg/cm z using oxygen generated by electrolysing water and steam having a temperature of from 300 to 600 ° attained by heat
Fuel and Energy Abstracts
July 2002 249