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Coke shrinkage and coking pressure during carbonization in a coke oven
03 Gaseous fuels (derived gaseous fuels) flux addition by blending with other coals with lower ash fusion temperatures. Coal blending to yield a SiOz/AlzOs ratio of 1.6-2.0 can minimize limestone flwc requirements and avoid some limitations which arise from slag crystallization. Limestone flux requirements can also be reduced by slag tapping at 1500°C rather than 14OO”C, but this should be balanced against increased operating costs and losses in cold gas efficiency at higher gasification temperatures. Australian export coals with very low iron contents, after limestone flux addition, appear to have the potential advantage that slag viscosities (and hence slag tapping performance) are essentially independent of variability in coal ash composition. This should lower gasifier operating and maintenance costs, offsetting the costs of flux addition. Ash and slag characteristics and possible strategies for optimum coal use in entrained-flow slagging gasifiers are discussed.
Biomass gasification in a laboratory-scale AFBG: influence of the location of the feeding point on the fuel-N conversion
Kinetic test reactions over a temperature range of 723 to 773 K of methane reforming with carbon dioxide was performed over rhodium dispersed on silica, Rh/SiOz, and vanadia-promoted silica, Rh/VOd SiOz. Transmission infrared spectroscopy was applied to observe the interaction of COz with the catalysts and the formation of surface intermediates during the C0zCH4 reforming reaction. XP spectroscopy and TPO was carried out to analyse the carbon deposition. It has been shown that the promotion of Rh/SiOz catalysts with vanadium oxide enhances the catalytic activity for COz reforming of methane and decreases the deactivation by carbon deposition. This is attributed to the formation of a partial VO, overlayer on the Rh surface, which reduces the size of accessible ensembles of Rh atoms required for coke formation and creates new sites at the Rh-VO. interfacial region that are regarded as active sites for carbon dioxide activation and dissociation.
00/00160
00/00165 Development of a process for manufacture of dimethyl ether using a bifunctionai catalyst
Vriesman, P. et al. Fuel, 2000, 79, (ii), 1371-1378. The influence of the feeding point on the conversion of fuel-nitrogen (fuel-N) was studied in an atmospheric fluidized bed gasifier. A comparison between feeding into the bed and feeding from the top of the reactor was made for different temperatures and equivalence ratios. Special emphasis was given to the distribution of fuel-N into NHs, HCN and char. The results show no influence of the feeding point on the nitrogen conversion to HCN and on the amount of nitrogen in char. Top feeding, however, results in lower conversion of fuel-N to NHs. The feeding points, and therefore the contact between the fuel particles and the surrounding oxygen-containing gas, as well as the oxygen concentration itself, are of great importance for the formation and destruction of NHs.
Bunkina, E.I. et al. Khim. Prom-st. ~MOSCOW),1999, 3, 144-149. (In Russian) The investigation presented in this paper is of a process for the manufacture of a catalyst for the conversion of synthesis gas to dimethyl ether and a reactor cooled with a finely dispersed heat carrier. Bifunctionai catalysts performed both methanol synthesis and its dehydration. Zinc-chromiumand copper-zinc-aluminum-containing catalysts were the synthesis catalysts, and y-alumina and silicaiite S-115 were used for the dehydration. In conclusion, it has been demonstrated that this technology has the potential to be used in units of large capacity.
W/O0161 Char cooling apparatus for coal gasification eauioment
Winiarski, J. Gospod. Paliwami Energ., 1999, 47, (7), 13-16. (In Polish) The most effective use of methane is for the production of electric and heat energy. The resources of coal-bed methane in Poland are vast. The only question is its profitable exploitation. In the case of methane from municipal waste landfill sites it can be utilized first of ail as a local energy carrier. However, the design of the landfill sites must be so that they can be used as a source of landfill gas and the connections must follow strict technical requirements.
Eg’ashira, T. et al. Jpn. Kokai Tokkyo Koho JP 11 279,567 [99 279,567] (Cl. CiOJ3/46), 12 Ott 1999, Appi. 1998/79,995, 26 Mar 1998. 6. (In Japanese) An apparatus for cooling char located in coal gasification equipment is described. The gasification equipment also contains a gasifier for coal and carbonaceous gasification, which is equipped with a heat exchanger tube for passing the cooling medium through for cooling the char recovered from a solid-gas separation apparatus.
00100162 Coke shrinkage and coking pressure during carbonization in a coke oven Nomura, S. and Arima, T. Fuel, 2000, 79, (13), 1603-1610. The relationship between coking pressure, lateral shrinkage and vertical shrinkage during carbonization in the coke oven was investigated. During the early and middle stage of the carbonization, no lateral shrinkage (gap between the coke cake and the oven wall) is observed since the outer coke layer is pressed against the oven wails by the coking pressure. It is not until the coking pressure peak ends in the later stage of the carbonization process that the lateral shrinkage starts to develop. The horizontal contraction of coke across the oven width is distributed between the lateral shrinkage and the gap at the oven centre. The final measured lateral shrinkage is 2-5 min and increases only by 1.6 mm per 10% increase in volatile matter. The coke cake is prevented from shrinking vertically when the coking pressure is high. The coke cake starts to shrink vertically when the downward force (the weight of coke cake) becomes greater than the upward frictional force between. the coke cake and the oven wail, which is caused by the coking pressure. The later the coke cake starts to shrink vertically, the smaller the final vertical coke shrinkage.
W/O0163 Composite catalyst for preparation of dimethyl ether from synthesis gas by one-step process Li, J. and Li, W. Faming Zhuanii Shenqing Gongkai Shumingshu CN 1,132,664 (Cl. BOlJ23/72), 9 Ott 1996, Appi. 95,103,655, 7 Apr 1995. 5. (In Chinese) Mixed metal oxides are the main components of the catalyst, specifically, Cu 20-40, Zn 10-30 and Al 40-60 moi%. Preparation of the catalyst involves co-precipitation impregnation, In addition the catalyst contains 0.5-2 mol% B as a promoter. The manufacturing process involves preparing a mixed solution of Cu nitrate and Zn nitrate, dropping the solution and 1 M Naz-COs into a beaker containing y-AizOs, allowing to coprecipitation and impregnation under stirring at 5&90” and pH 6-8, and agitation for 15-60 minutes, filtering, water washing, drying at 80-120” for 8-16 hours, caicining at 350-450” for 8-16 hours and finally tablet formation.
W/W164 CO1 reforming of methane over vanadia-promoted Rh/SI02 catalysts
Sigl, M. er al. Top. Caral., 1999, 8, (3,4), 211-222.
00100166 Economical use of methane as a factor for improvement of the natural environment
Effect of mixed rare-earth additive on Ni/Ai203 catalyst for methane partial oxidation to syngas
00100167
Wan, J. et al. Tianranqi Huagong, 1999, 24, (3) 28-31. (In Chinese) In a micro continuous-flow apparatus, the reaction performances of methane partial oxidation to syngas over Ni-Re/AizOs catalysts have been investigated. With some of the catalysts the life-time has been tested for 500 hours. The catalysts have been characterized by BET, XRD and XPS techniques. It is demonstrated that the Re additives can elevate the catalyst activities and resist the formation of NiAiz04.
OOIOO166 Effect of support on the performance of Ni-based catalysts for CHJC02 reforming to syngas Li, J.T. ef al. Fenzi Cuihua, 1999, 13, (4), 277-281. (In Chinese) Ni/MgO, Ni/CaO and Ni/CeOz catalysts were prepared and their catalytic performance in CH.&Oz reforming to syngas was examined. From the experimental results it is evident that MgO is the best supporter! since the interaction between Ni and MgO is stronger than that of Ni-CaO and Ni-CeOz. The in si~u CO disproportionation and CH4 decomposition experiments showed that these reactions were promoted by the adsorbed hydrogen on the.surface of the catalysts, thus avoiding the deposition of carbon.
00100169 Effects of supports on partial oxidation of methane to syngas Yan, 0. ef al. Tianranqi Huagong, 1999, 24, (3). 4-8. (In Chinese) In a fixed-bed flow reactor, the activity of nickel catalyst on different supports were studied. The influences of support component, surface area and pore radius on the performance of catalysts were investigated through temperature-programmed reduction (TPR) and X-ray diffraction analysis. It is found that the inert material as (Ca) MgA1z04, with certain surface area and pore radius, high thermal stability and fine heat-conduction is an ideal catalyst support for partially oxidizing methane to syngas. 00100170 Entrained-bed gasification of fuel, residual and waste materials Schingnitz, M. and Gorz, J. Umrvelr, 1999, 29, (9), 48-51. (In German) The adaptation of the entrained gasification process (originally developed far lignite dust) to solid residual and waste materials is presented. For this purpose, pyrolysis at 450-550” is carried out on the materials and the obtained gas, oil and coke are processed and mixed before being injected into the gasification reactor. The produced HFuel and Energy Abstracts
January 2001
17
Biomass gasification in a laboratory-scale AFBG: influence of the location of the feeding point on the fuel-N conversion
Kinetic test reactions over a temperature range of 723 to 773 K of methane reforming with carbon dioxide was performed over rhodium dispersed on silica, Rh/SiOz, and vanadia-promoted silica, Rh/VOd SiOz. Transmission infrared spectroscopy was applied to observe the interaction of COz with the catalysts and the formation of surface intermediates during the C0zCH4 reforming reaction. XP spectroscopy and TPO was carried out to analyse the carbon deposition. It has been shown that the promotion of Rh/SiOz catalysts with vanadium oxide enhances the catalytic activity for COz reforming of methane and decreases the deactivation by carbon deposition. This is attributed to the formation of a partial VO, overlayer on the Rh surface, which reduces the size of accessible ensembles of Rh atoms required for coke formation and creates new sites at the Rh-VO. interfacial region that are regarded as active sites for carbon dioxide activation and dissociation.
00/00160
00/00165 Development of a process for manufacture of dimethyl ether using a bifunctionai catalyst
Vriesman, P. et al. Fuel, 2000, 79, (ii), 1371-1378. The influence of the feeding point on the conversion of fuel-nitrogen (fuel-N) was studied in an atmospheric fluidized bed gasifier. A comparison between feeding into the bed and feeding from the top of the reactor was made for different temperatures and equivalence ratios. Special emphasis was given to the distribution of fuel-N into NHs, HCN and char. The results show no influence of the feeding point on the nitrogen conversion to HCN and on the amount of nitrogen in char. Top feeding, however, results in lower conversion of fuel-N to NHs. The feeding points, and therefore the contact between the fuel particles and the surrounding oxygen-containing gas, as well as the oxygen concentration itself, are of great importance for the formation and destruction of NHs.
Bunkina, E.I. et al. Khim. Prom-st. ~MOSCOW),1999, 3, 144-149. (In Russian) The investigation presented in this paper is of a process for the manufacture of a catalyst for the conversion of synthesis gas to dimethyl ether and a reactor cooled with a finely dispersed heat carrier. Bifunctionai catalysts performed both methanol synthesis and its dehydration. Zinc-chromiumand copper-zinc-aluminum-containing catalysts were the synthesis catalysts, and y-alumina and silicaiite S-115 were used for the dehydration. In conclusion, it has been demonstrated that this technology has the potential to be used in units of large capacity.
W/O0161 Char cooling apparatus for coal gasification eauioment
Winiarski, J. Gospod. Paliwami Energ., 1999, 47, (7), 13-16. (In Polish) The most effective use of methane is for the production of electric and heat energy. The resources of coal-bed methane in Poland are vast. The only question is its profitable exploitation. In the case of methane from municipal waste landfill sites it can be utilized first of ail as a local energy carrier. However, the design of the landfill sites must be so that they can be used as a source of landfill gas and the connections must follow strict technical requirements.
Eg’ashira, T. et al. Jpn. Kokai Tokkyo Koho JP 11 279,567 [99 279,567] (Cl. CiOJ3/46), 12 Ott 1999, Appi. 1998/79,995, 26 Mar 1998. 6. (In Japanese) An apparatus for cooling char located in coal gasification equipment is described. The gasification equipment also contains a gasifier for coal and carbonaceous gasification, which is equipped with a heat exchanger tube for passing the cooling medium through for cooling the char recovered from a solid-gas separation apparatus.
00100162 Coke shrinkage and coking pressure during carbonization in a coke oven Nomura, S. and Arima, T. Fuel, 2000, 79, (13), 1603-1610. The relationship between coking pressure, lateral shrinkage and vertical shrinkage during carbonization in the coke oven was investigated. During the early and middle stage of the carbonization, no lateral shrinkage (gap between the coke cake and the oven wall) is observed since the outer coke layer is pressed against the oven wails by the coking pressure. It is not until the coking pressure peak ends in the later stage of the carbonization process that the lateral shrinkage starts to develop. The horizontal contraction of coke across the oven width is distributed between the lateral shrinkage and the gap at the oven centre. The final measured lateral shrinkage is 2-5 min and increases only by 1.6 mm per 10% increase in volatile matter. The coke cake is prevented from shrinking vertically when the coking pressure is high. The coke cake starts to shrink vertically when the downward force (the weight of coke cake) becomes greater than the upward frictional force between. the coke cake and the oven wail, which is caused by the coking pressure. The later the coke cake starts to shrink vertically, the smaller the final vertical coke shrinkage.
W/O0163 Composite catalyst for preparation of dimethyl ether from synthesis gas by one-step process Li, J. and Li, W. Faming Zhuanii Shenqing Gongkai Shumingshu CN 1,132,664 (Cl. BOlJ23/72), 9 Ott 1996, Appi. 95,103,655, 7 Apr 1995. 5. (In Chinese) Mixed metal oxides are the main components of the catalyst, specifically, Cu 20-40, Zn 10-30 and Al 40-60 moi%. Preparation of the catalyst involves co-precipitation impregnation, In addition the catalyst contains 0.5-2 mol% B as a promoter. The manufacturing process involves preparing a mixed solution of Cu nitrate and Zn nitrate, dropping the solution and 1 M Naz-COs into a beaker containing y-AizOs, allowing to coprecipitation and impregnation under stirring at 5&90” and pH 6-8, and agitation for 15-60 minutes, filtering, water washing, drying at 80-120” for 8-16 hours, caicining at 350-450” for 8-16 hours and finally tablet formation.
W/W164 CO1 reforming of methane over vanadia-promoted Rh/SI02 catalysts
Sigl, M. er al. Top. Caral., 1999, 8, (3,4), 211-222.
00100166 Economical use of methane as a factor for improvement of the natural environment
Effect of mixed rare-earth additive on Ni/Ai203 catalyst for methane partial oxidation to syngas
00100167
Wan, J. et al. Tianranqi Huagong, 1999, 24, (3) 28-31. (In Chinese) In a micro continuous-flow apparatus, the reaction performances of methane partial oxidation to syngas over Ni-Re/AizOs catalysts have been investigated. With some of the catalysts the life-time has been tested for 500 hours. The catalysts have been characterized by BET, XRD and XPS techniques. It is demonstrated that the Re additives can elevate the catalyst activities and resist the formation of NiAiz04.
OOIOO166 Effect of support on the performance of Ni-based catalysts for CHJC02 reforming to syngas Li, J.T. ef al. Fenzi Cuihua, 1999, 13, (4), 277-281. (In Chinese) Ni/MgO, Ni/CaO and Ni/CeOz catalysts were prepared and their catalytic performance in CH.&Oz reforming to syngas was examined. From the experimental results it is evident that MgO is the best supporter! since the interaction between Ni and MgO is stronger than that of Ni-CaO and Ni-CeOz. The in si~u CO disproportionation and CH4 decomposition experiments showed that these reactions were promoted by the adsorbed hydrogen on the.surface of the catalysts, thus avoiding the deposition of carbon.
00100169 Effects of supports on partial oxidation of methane to syngas Yan, 0. ef al. Tianranqi Huagong, 1999, 24, (3). 4-8. (In Chinese) In a fixed-bed flow reactor, the activity of nickel catalyst on different supports were studied. The influences of support component, surface area and pore radius on the performance of catalysts were investigated through temperature-programmed reduction (TPR) and X-ray diffraction analysis. It is found that the inert material as (Ca) MgA1z04, with certain surface area and pore radius, high thermal stability and fine heat-conduction is an ideal catalyst support for partially oxidizing methane to syngas. 00100170 Entrained-bed gasification of fuel, residual and waste materials Schingnitz, M. and Gorz, J. Umrvelr, 1999, 29, (9), 48-51. (In German) The adaptation of the entrained gasification process (originally developed far lignite dust) to solid residual and waste materials is presented. For this purpose, pyrolysis at 450-550” is carried out on the materials and the obtained gas, oil and coke are processed and mixed before being injected into the gasification reactor. The produced HFuel and Energy Abstracts
January 2001
17