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03769 Study on coal gasification in steam fluidized bed
04
97103766 Study of macro-mixing process for jet-entrained gasifier. (I). Cold model concentration distribution Wang, F. et al. Huagong Xuebao, 1997, 48, (2), 193-199. (In Chinese) The concentration distribution of a jet-entrained gasifier is measured in a large scale cold model (1000 mm times; 4000 mm) gasifier based on the twin-fluid concentric intersect jet nozzle. The effect of the momentum ratio of annular jet to concentric jet on macro-mixing process is also investigated. The variation of dimensionless concentration, dimensionless maximum concentration, centre mixing fraction and dimensionless concentration halfradius is proposed. Study on coal gasification in steam fluidfzed bed. 97103769 Cui, L. et al. Ranliao Huaxue Xuehao, 1997, 25, (2), 97-103. (In Chinese) Experiments on two Chifeng lignites were conducted in a fluidized bed coal gasification system to study the effects of bed temperature and fluidizing state on product gas yield and compositions. A comprehensive model based on single process models was developed. It uses a comparative method to determine the model parameters which depend on coal type and experimental conditions, so that the model predictions reflect the experiment accurately. A non-linear programming method was utilized to determine these parameters. The results of model prediction correlated well with the experimental data proving this parameter identification method is an effective approach for the modelling of complex processes. 97103770 Study on process mechanism for gasification of char particle Kwahak Kisul Yonguso, Kim, .I. H. and Chang, Y. H. Nonmunjip-Snoop 1995, 23-1, 501-511. (In Korean) In order to analyse the gasification mechanism of a porous semicokeparticle in a gas-phase environment, a mathematical model was developed. The profiles of concentration, temperature, and gasification rate depended on the particle size; the temperature inside the particle was obtained through the computer simulation of a mathematical model. This model consisted of material and energy balance equations. The surface area of solid particle was calculated by the random pore model. The results are reported in detail. 97103771 Technical and economic indexes for a pilot unit for semi-coking and gasification of brown coal Savinov, M. et al. Ugol’ Ukr. 1996, (9) 25-26. (In Russian) The economic viability of construction of a pilot unit for semi-coking and gasification of brown coal at the output level of 500 thousand t/year was confirmed through calculations. Thermodynamic and environmental assessment of 97103772 integrated gasification and methanol synthesis (IGMS) energy systems with CO2 removal Cau, G. ef al. Energy Convers. Manage., 1997, 38, (Suppl., Proceedings of the Third International Conference on Carbon Dioxide Removal, 1996) Sl79-S186. The extensive utilization of the huge world coal reserves gives rise to environmental and technical concerns. Only advanced energy conversion technologies can now overcome this. Integrated coal gasification and methanol synthesis power plants can perform a load-following service, by producing and storing liquid methanol, and reduce the carbon dioxide emissions, by removing COz and disposing it outside the atmosphere. In this paper, a comparative performance analysis among the different IGMS power plants has been carried out, by evaluating the influence of the coal gasification and methanol synthesis technologies on the main performance characteristics, including methanol production. the specific COz emissions and the overall efficiency.
04
BY-PRODUCTS TO FUELS
RELATED
97193773 Agricultural uses of alkaline fluidized bed combustion ash: case studies Stout, W. L. et al. Fuel, 1997, 76, (8) 767-769. Ash produced in fluidized bed combustion is used as a substitute for agricultural lime on dairy farms in northern New York state and on fruit and nut crops in the San Joaquin Valley of California. 97103774 Beneficial use of spent coal ash with municipal wastewater residuals in synthetic soil production Faulmann, E. L. et al. WEFIAWWA Jt. ResidualslBioso1id.sConf, Proc., 4th, 1995, 6133-6140. N-Viro Soil (NVS) produced by full-scale municipal facilities using fluidized bed ash (FBA) of fly ash (FA) alkali admixtures and facilities using cement and lime kiln dusts (CKD) is discussed. The soil made with coal ashes had similar biological, physical and chemical characteristics to soil products made with standard alkali admixtures. The stabilized and soillike product made with FBA displayed favourable odour characteristics, as determined by extracted fatty acids profiles. It also displayed enhanced
By-products
related to fuels
storage and ageing characteristics and agronomic characteristics. Land on which soil made from wastewater and coal ash waste products had been experimental applied yielded greater crop harvest than plots without soil amendment. These results not only emphasise the benefits to be gained combining the waste streams from both coal-burning industries and municipal wastewater treatment but it closes the utilization cycle on beneficial use of coal wastes in the ability to reclaim mine spoils with coalash products. 97103775 Brominated pitch-based carbon fibers Klimenko, 1. V. et al. Synrh. Met., 1997, 86, (l-3). 2337-2338. Characterization of pitch-based carbon fibres, brominated during 2-144 h. was undertaken. They were characterized by their electric resistivity in the temperature range lo-300 K, micro-Raman spectroscopy in the spectral region 100-3100 cm-’ and TGA with the purpose of determination of Br state and changes in the fibre structure on a molecular level upon the bromination process. The data were explained by degradation of the graphite network, increasing of the finite crystal phase, appearance and increase of C in amorphous state, and the gain of graphite layers number adjacent to Br. Further study into the Br state in C fibres was also completed. 97103776 Building materials containing coal ashes Yoshida, T. Jpn. Kokai Tokkyo Koho JP 09,110,554 [97,110,554] (Cl. C04B38/10), 28 Apr 1997, Appl. 95/299,136, 24 Ott 1995, 5 pp. (In Japanese) A slurry containing coal ash, cement, foaming agent, and water make up these materials. Their compression strength after 7 days is 2-5 x 9.8 N/cm , and unit vol. wt. 0.5-1.2 g cm’ under solidified conditions. The water ratio of the slurry is preferably 45-65%. 97103777 Co-carbonization of 9-chloroborafluorene and pitch; synthesis of B/C materials Hu, R. and Chung, T. C. Carbon, 1997, 35, (S), 1101-1109. Previous research efforts in the development of boron containing carbon (B/C) materials are extended in this work. The chemistry is based on the cocarbonization reaction between 9chloroborafluorene precursor and FCC decant oil pitch. The yield of low temperature anisotropic carbon from the commercial pitch was dramatically improved via addition of small amounts of 9-chloroborafluorene,. This method results in a broad range of B/C materials and is both simple and effective. In addition, the co-carbonization reaction provides direct evidence of boron-enhanced graphitization and the effect of boron content on crystal growth. By incorporating small amounts of boron precursor, the graphitization temperature of pitch can generally be lowered by several hundred degrees, and a large crystal size with low density-spacing is obtained at 2300°C. 97103778 Coal ash chemistrv for ash utilization. Chemical ~_ approach to the effective utiliraiion of coal ash in Japan Shinozaki, S. and Ozasa, K. Proc. Int. Tech. Conf. Coal Util. Fuel Syst., 1997. 22. 377-388. Preli’mmary results from a programme established to clarify mineral behaviour in coal from both aspects of coal ash slugging and effective use. 97103779 The contribution of silica fume and siliceousaluminous fly ash to the compressive strength of concretequantification Wailer, V. et al. Bull. Lab. Pants Chaussees, 1997, 208, 53-65. (In French) From the Feret relationship, de Larrad has developed a model for the compressive strength of concrete containing pozzolans (silica fume or silicaalumina fly ash). This model has been recalibrated on the basis of a very large data set relating to cement containing silica fume, fly ash or a combination of both, as set out in this paper. The contribution of pozzolans to the compressive strength of concrete is expressed by using a timedependent activity coefficient. The model’s accuracy for the entire amount of collected experimental data is 2.6 MPa. The activity coefficients of pozzolans depend considerably on their specific surfaces. 97lQ3780 Development of early strength-type portland fly-ash cement Hou, H. Huanjing Gongcheng, 1995, 13, (6), 37-40. (In Chinese) According to the forming mechanism of cement clinker minerals, cement clinker minerals are chosen. Fly ash is used as substitute of clay as raw materials and subsequently, early and high strength type cement clinker has been developed. The amount of alite (Cs5) in the clinker is very high. Experiments show that early strength of type No. 425 fly-ash cement can be achieved by the cement clinker when the amount of added fly ash is 30-40 wt%. 97103781 Effect of lightweight fly ash aggregate microstructure on the strength of concretes Wasserman, R. and Bentur, A. Gem. Concr. Res., 1997, 27, (4) 525-537. Modification was carried out on the structure and properties of sintered fly ash lightweight aggregate. This entailed heat and polymer treatments to obtain aggregates different in their strength, absorption and pozzolanic activity. These properties were accounted for by changes in their microstructure. The strength of concretes of equal effective water/cement ratio prepared from these aggregates was determined at different stages to
Fuel and Energy Abstracts
September
1997
317
97103766 Study of macro-mixing process for jet-entrained gasifier. (I). Cold model concentration distribution Wang, F. et al. Huagong Xuebao, 1997, 48, (2), 193-199. (In Chinese) The concentration distribution of a jet-entrained gasifier is measured in a large scale cold model (1000 mm times; 4000 mm) gasifier based on the twin-fluid concentric intersect jet nozzle. The effect of the momentum ratio of annular jet to concentric jet on macro-mixing process is also investigated. The variation of dimensionless concentration, dimensionless maximum concentration, centre mixing fraction and dimensionless concentration halfradius is proposed. Study on coal gasification in steam fluidfzed bed. 97103769 Cui, L. et al. Ranliao Huaxue Xuehao, 1997, 25, (2), 97-103. (In Chinese) Experiments on two Chifeng lignites were conducted in a fluidized bed coal gasification system to study the effects of bed temperature and fluidizing state on product gas yield and compositions. A comprehensive model based on single process models was developed. It uses a comparative method to determine the model parameters which depend on coal type and experimental conditions, so that the model predictions reflect the experiment accurately. A non-linear programming method was utilized to determine these parameters. The results of model prediction correlated well with the experimental data proving this parameter identification method is an effective approach for the modelling of complex processes. 97103770 Study on process mechanism for gasification of char particle Kwahak Kisul Yonguso, Kim, .I. H. and Chang, Y. H. Nonmunjip-Snoop 1995, 23-1, 501-511. (In Korean) In order to analyse the gasification mechanism of a porous semicokeparticle in a gas-phase environment, a mathematical model was developed. The profiles of concentration, temperature, and gasification rate depended on the particle size; the temperature inside the particle was obtained through the computer simulation of a mathematical model. This model consisted of material and energy balance equations. The surface area of solid particle was calculated by the random pore model. The results are reported in detail. 97103771 Technical and economic indexes for a pilot unit for semi-coking and gasification of brown coal Savinov, M. et al. Ugol’ Ukr. 1996, (9) 25-26. (In Russian) The economic viability of construction of a pilot unit for semi-coking and gasification of brown coal at the output level of 500 thousand t/year was confirmed through calculations. Thermodynamic and environmental assessment of 97103772 integrated gasification and methanol synthesis (IGMS) energy systems with CO2 removal Cau, G. ef al. Energy Convers. Manage., 1997, 38, (Suppl., Proceedings of the Third International Conference on Carbon Dioxide Removal, 1996) Sl79-S186. The extensive utilization of the huge world coal reserves gives rise to environmental and technical concerns. Only advanced energy conversion technologies can now overcome this. Integrated coal gasification and methanol synthesis power plants can perform a load-following service, by producing and storing liquid methanol, and reduce the carbon dioxide emissions, by removing COz and disposing it outside the atmosphere. In this paper, a comparative performance analysis among the different IGMS power plants has been carried out, by evaluating the influence of the coal gasification and methanol synthesis technologies on the main performance characteristics, including methanol production. the specific COz emissions and the overall efficiency.
04
BY-PRODUCTS TO FUELS
RELATED
97193773 Agricultural uses of alkaline fluidized bed combustion ash: case studies Stout, W. L. et al. Fuel, 1997, 76, (8) 767-769. Ash produced in fluidized bed combustion is used as a substitute for agricultural lime on dairy farms in northern New York state and on fruit and nut crops in the San Joaquin Valley of California. 97103774 Beneficial use of spent coal ash with municipal wastewater residuals in synthetic soil production Faulmann, E. L. et al. WEFIAWWA Jt. ResidualslBioso1id.sConf, Proc., 4th, 1995, 6133-6140. N-Viro Soil (NVS) produced by full-scale municipal facilities using fluidized bed ash (FBA) of fly ash (FA) alkali admixtures and facilities using cement and lime kiln dusts (CKD) is discussed. The soil made with coal ashes had similar biological, physical and chemical characteristics to soil products made with standard alkali admixtures. The stabilized and soillike product made with FBA displayed favourable odour characteristics, as determined by extracted fatty acids profiles. It also displayed enhanced
By-products
related to fuels
storage and ageing characteristics and agronomic characteristics. Land on which soil made from wastewater and coal ash waste products had been experimental applied yielded greater crop harvest than plots without soil amendment. These results not only emphasise the benefits to be gained combining the waste streams from both coal-burning industries and municipal wastewater treatment but it closes the utilization cycle on beneficial use of coal wastes in the ability to reclaim mine spoils with coalash products. 97103775 Brominated pitch-based carbon fibers Klimenko, 1. V. et al. Synrh. Met., 1997, 86, (l-3). 2337-2338. Characterization of pitch-based carbon fibres, brominated during 2-144 h. was undertaken. They were characterized by their electric resistivity in the temperature range lo-300 K, micro-Raman spectroscopy in the spectral region 100-3100 cm-’ and TGA with the purpose of determination of Br state and changes in the fibre structure on a molecular level upon the bromination process. The data were explained by degradation of the graphite network, increasing of the finite crystal phase, appearance and increase of C in amorphous state, and the gain of graphite layers number adjacent to Br. Further study into the Br state in C fibres was also completed. 97103776 Building materials containing coal ashes Yoshida, T. Jpn. Kokai Tokkyo Koho JP 09,110,554 [97,110,554] (Cl. C04B38/10), 28 Apr 1997, Appl. 95/299,136, 24 Ott 1995, 5 pp. (In Japanese) A slurry containing coal ash, cement, foaming agent, and water make up these materials. Their compression strength after 7 days is 2-5 x 9.8 N/cm , and unit vol. wt. 0.5-1.2 g cm’ under solidified conditions. The water ratio of the slurry is preferably 45-65%. 97103777 Co-carbonization of 9-chloroborafluorene and pitch; synthesis of B/C materials Hu, R. and Chung, T. C. Carbon, 1997, 35, (S), 1101-1109. Previous research efforts in the development of boron containing carbon (B/C) materials are extended in this work. The chemistry is based on the cocarbonization reaction between 9chloroborafluorene precursor and FCC decant oil pitch. The yield of low temperature anisotropic carbon from the commercial pitch was dramatically improved via addition of small amounts of 9-chloroborafluorene,. This method results in a broad range of B/C materials and is both simple and effective. In addition, the co-carbonization reaction provides direct evidence of boron-enhanced graphitization and the effect of boron content on crystal growth. By incorporating small amounts of boron precursor, the graphitization temperature of pitch can generally be lowered by several hundred degrees, and a large crystal size with low density-spacing is obtained at 2300°C. 97103778 Coal ash chemistrv for ash utilization. Chemical ~_ approach to the effective utiliraiion of coal ash in Japan Shinozaki, S. and Ozasa, K. Proc. Int. Tech. Conf. Coal Util. Fuel Syst., 1997. 22. 377-388. Preli’mmary results from a programme established to clarify mineral behaviour in coal from both aspects of coal ash slugging and effective use. 97103779 The contribution of silica fume and siliceousaluminous fly ash to the compressive strength of concretequantification Wailer, V. et al. Bull. Lab. Pants Chaussees, 1997, 208, 53-65. (In French) From the Feret relationship, de Larrad has developed a model for the compressive strength of concrete containing pozzolans (silica fume or silicaalumina fly ash). This model has been recalibrated on the basis of a very large data set relating to cement containing silica fume, fly ash or a combination of both, as set out in this paper. The contribution of pozzolans to the compressive strength of concrete is expressed by using a timedependent activity coefficient. The model’s accuracy for the entire amount of collected experimental data is 2.6 MPa. The activity coefficients of pozzolans depend considerably on their specific surfaces. 97lQ3780 Development of early strength-type portland fly-ash cement Hou, H. Huanjing Gongcheng, 1995, 13, (6), 37-40. (In Chinese) According to the forming mechanism of cement clinker minerals, cement clinker minerals are chosen. Fly ash is used as substitute of clay as raw materials and subsequently, early and high strength type cement clinker has been developed. The amount of alite (Cs5) in the clinker is very high. Experiments show that early strength of type No. 425 fly-ash cement can be achieved by the cement clinker when the amount of added fly ash is 30-40 wt%. 97103781 Effect of lightweight fly ash aggregate microstructure on the strength of concretes Wasserman, R. and Bentur, A. Gem. Concr. Res., 1997, 27, (4) 525-537. Modification was carried out on the structure and properties of sintered fly ash lightweight aggregate. This entailed heat and polymer treatments to obtain aggregates different in their strength, absorption and pozzolanic activity. These properties were accounted for by changes in their microstructure. The strength of concretes of equal effective water/cement ratio prepared from these aggregates was determined at different stages to
Fuel and Energy Abstracts
September
1997
317