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00080 Scenarios for power production with biomass in the Finnish forest industry
01
13C NMR study of structural QQlOOO75 Quantitative variations within the vltrinite and lnertlnlte maceral groups for a semlfuslnlte-rich bituminous coal Maroto-Valer, M.er al. Fuel, 1998, 77,(8), 805-813. To determine the structural variation within vitrinite and inertinite maceral groups, fractions with purities over 90% in vitrinite and semifusinite were obtained by density gradient centrifugation from a medium volatile Australian bituminous coal and the bulk structural compositions of the maceral concentrates were determined by the quantifiably reliable single pulse excitation (SPE) solid state 13C NMR technique. Due to the unfavourable spin dynamics as previously reported for coals and chars, the aromaticities determined by cross polarization are often lower than those by SPE. As expected, the aromaticities of the vitrinite fractions are significantly lower than those of the semifusinite ones, but the aromaticity, the fraction of non-protonated aromatic carbon and the number of rings per cluster all increase with density within both the maceral groups. From three to six and nine to over 1.5 aromatic rings are contained in the vitrinite and semifusinite fractions, respectively. Me groups account for greater proportions of the aliphatic carbon with increasing density. With the variations evident in random reflectance these structural trends are consistent.
Reduction and reductive alkylatlon of coals using 99100076 deuterlum containing compounds Kozlowski, M. and Wachowska, H. Fuel, 1998, 77, (6) 591-599. In the system potassium/liquid ammonia two Polish coals are subjected to the reactions of reduction and reductive alkylation. The classical methods of reduction and reductive alkylation of coal are modified by replacing the conventional protonating and alkylating agents by the ones containing deuterium atoms. Reduction is performed with CzH50D whereas reductive alkylation uses CD31. Fragmentation of the coal structure proceeds mainly by cleavage of methylene bridges. The products of reactions of both kinds are subjected to extraction with dichloromethane. The yield of extraction of the modified coals is significantly greater than that of raw coals. Average molar weights of the extracts are determined and elemental and spectral analyses of the raw materials and products are performed. Also discussed is the effect of the kind of hydrogen isotope in the modifying agents on the results obtained. 99160077
The regional biomass-energy agency (ERBE): an opportunity for the biomass-energy development In Wallonla
Lemaire, Mater..
P. ert al. Making Bus. Biomass Energy, Environ., Chemical, Fibers Edited by Proc. Biomass Confi Am. 3rd, 1997, (2), 1515-1523.
Overend, R. P. and Chornet, E. In 1995, a biomass-energy agency (ERBE) was set up by the European Commission (Directorate-General for Energy) and the Walloon government to promote and build biomass-energy projects in Wallonia (Belgium). A survey of biomass-energy potential indicates that wood-energy seems to offer the best utilization opportunities. Forest and logging residues, sawmills’ and joineries’ off-cuts, pallets residues, etc. could be burnt in wood district heating units with a significant social benefit. Consequently, the ERBE Agency is trying to set up projects in this way as in Austria or in Sweden. It serves to inform industries and municipalities about biomassenergy, to advise them in the building of biomass-energy projects, to identity their energy needs and their biomass resources, to carry out prefeasibility studies, to inform them about financing opportunities, and so on. 99100076
Regression analysis of the composition and properties of macerals of Kuznetsk Basin coals with different degrees of reduction Gagarin, S. G. Woks Khim., 1998, (2) 2-6. (In Russian) Determined is the correlation between the H/C ratio and volatile matter content of vitrinite and inertinite Kuznetsk Basin coals with different degrees of reduction.
Research on agglomeration In a coal gaslfler with 99/00079 twin fluldized beds Xiong, Y. et al.
Proc. Annu. Int. PiUsburgh Coal Conf, 1997, 14, (20), 16-
22.
In this paper agglomeration of bed material in coal gasification with twin fluidized beds is studied. Optical microscope, X-ray diffraction, and thermal analyses of agglomerates were carried out and the mechanism of agglomeration and bed defluidization were discussed.
Scenarios for power production with biomass in the Finnish forest Industry
QQ/QQQ60 Nousiamen,
I. K. et al.
Making Bus. Biomoss Energy, Environ., Fibers Mater., Proc. Biomass Conf. Am. 3rd, 1997, (2), 1345-1351.
Chemical,
Edited by Overend, R. P. and Chornet, E. Presented in this study are three scenarios for power production with biomass in Finnish pulp and paper mills. The basic scenario assumes that the production capacity in the forest industry increases as in the past. The green energy scenario assumes that there is a strong demand from the market for sustainable green energy production. The maximum scenario assumes that the production capacity of chemical pulp increases significantly and the use of wood raw material extends to the maximum level. According to the basic scenario the use of biofuels in the pulp and paper mills will increase from starting level, 3.24 Mtoe in 1992, to 5.07 Mtoe by
Solid
fuels
(sources,
winning,
propedies)
the year 2010. The utilization potential of biofuels will increase to 5.45 Mtoe in green energy and to 6.43 Mtoe in the maximum biofuels scenario. The power production with biomass will increase from the starting level, 572 MW in 1992, to 930 MW in the basic, to 1100 MW in the green energy and to 1670 MW in the maximum biofuels scenario by the year 2010. 9QlclQct61
Separation of fossil resin from northeast China
coal Xie, H. et al. Proc. Annu. Int. Piftsburgh Cool Conf., 1997, 14, (6). 15-23. In China some coal fields contain macroscopic fossil resins, but these fossil resins have not been recovered commercially. The distribution of fossil resin in coal from north-east China was characterized before recovering it by flotation and gravity separation. The fossil resin particles whose weight accounted for more than 99% of all fossil resin in the sample were larger than 0.125 mm. A concentrated product that contained almost 100% fossil resin at a recovery of more than 88% was obtained from a feed containing 1.72% fossil resin using a shaking table followed by float-sink separation with a sodium chloride solution (1.1 g/ml). By conventional single stage flotation, a fossil resin concentrate containing 48% fossil resin at a recovery of 95% was obtained from a feed containing 11.4% fossil resin. The grade of the concentrate was increased to a certain extent by treating the feed with Hz02 solution before flotation, but the recovery of fossil resin decreased greatly.
Shrlnkin -bed model for percolation process applled to dilute-ac 9d pretreatment/hydrolysis of cellulosic biomass
QQlQQQ62
Chen, R. et al. Appl. Biochemical Biotechnol., 1998, (70-72), 37-49. Hemicellulose is biphasic upon dilutive-acid hydrolysis for many lignocellulosic substrates, which leads to a modified percolation process employing simulated two-stage reverse-flow. This process has been proven to attain substantially higher sugar yields and concentrations over the single-stage percolation process.The dilutive-acid pretreatment of biomass solubilizes the hemicellulose fraction in the solid biomass, leaving less solid biomass in the reactor and reducing the bed. Therefore, a bed-shrinking mathematic kinetic model was developed to describe the two-stage reverseflow reactor operated for hydrolysing biphasic substrates, including hemicellulose, in corn cob/stover mixture (CCSM). The simulation indicates that the shrinking-bed operation increases the sugar yield by about 5%, compared to the non-shrinking bed operation in which 1 reactor volume of liquid passes through the reactor. A simulated optimal run further revealed that the fast portion of hemicellulose was almost completely hydrolysed in the first stage, and the slow portion of hemicellulose was hydrolysed in the second stage. Under optimal conditions, the bed shrank 27%, and a sugar yield over 95% was attained.
Slagging and fluidity behavior of coal ash under gaslfler environment
99lOQ663
Kim, H. T. et al. Proc. Annu. Int. Pinsburgh Coal Conf., 1997, 14, (26), l-11. In this study the objective is to predict the slagging and fluidity behaviour of coal ashes from the physical/chemical properties of parent coals to determine the optimum operating parameter of slagging-type coal gasifier. Three types of coal samples, such as Alaska Usibelli, China Datong and Posco (blended coal), were analysed for their ash composition and ash fusion temperature. Optimum quantity of CaO addition is evaluated with considering negative effect of CaO addition on gasification reaction to investigate the effect of flux addition on ash slagging behaviour. The effect of blending of Posco coal with Alaska and Datong coal on ash slagging is also investigated to expand the variety and performance of coal types in slagging-type entrained-bed gasifier. The results of the experiment show that the optimum CaO fluxing quantity is 10%. 20% on Alaska and Dating coal, respectively. However, optimum blending ratio for ash slagging is not found when mixing Posco coal with Alaska or Datong coals. Melting and slagging characteristics of coal ash samples with changing temperature were examined in detail by DTA. ASTM ash melting temperatures as well as critical viscosity temperature are compared with TGA and DTA profiles. DTA experiments illustrate that coal ash starts to melt before the IDT (initial deformation temperature) and that theoretical T,, (critical viscosity temperature) is well correlated with DTA profile. Experiment of ash fluidity were also carried on with the Alaska and Datong coal ashes using a high temperature viscometer. The experimental viscosity data was compared with the calculated viscosity and results show good correlation. As a result, viscosity of coal ash could be calculated with Watt and Fereday equation in high temperature range. QQlOOO64
Slovak brown coal characterization caustic leaching
after molten
Balaz, P. et al. Proc. Annu. Int. Pittsburgh Cool Conf., 1997, 14, (7). 16-26. Leaching of Slovak brown coal with molten sodium hydroxide at 380” for 20 min decreases its sulfur content from 3.26 to 0.26 wt%. QQlOOO65
Solvent swelling rates of low rank coals and lmpllcatlons regarding their structure
Otake, Y. and Suuberg, Eric M. Fuel, 1998, 77, (8) 901-904. Low rank US coals have been measured, the rates of solvent swelling of a suite in various organic solvents at various temperatures. The equilibrium extents of swelling are independent of temperature within the temperature range studied (25-70°C). The rate of the swelling process was generally
Fuel and Energy Abstracts
January 1999 9
13C NMR study of structural QQlOOO75 Quantitative variations within the vltrinite and lnertlnlte maceral groups for a semlfuslnlte-rich bituminous coal Maroto-Valer, M.er al. Fuel, 1998, 77,(8), 805-813. To determine the structural variation within vitrinite and inertinite maceral groups, fractions with purities over 90% in vitrinite and semifusinite were obtained by density gradient centrifugation from a medium volatile Australian bituminous coal and the bulk structural compositions of the maceral concentrates were determined by the quantifiably reliable single pulse excitation (SPE) solid state 13C NMR technique. Due to the unfavourable spin dynamics as previously reported for coals and chars, the aromaticities determined by cross polarization are often lower than those by SPE. As expected, the aromaticities of the vitrinite fractions are significantly lower than those of the semifusinite ones, but the aromaticity, the fraction of non-protonated aromatic carbon and the number of rings per cluster all increase with density within both the maceral groups. From three to six and nine to over 1.5 aromatic rings are contained in the vitrinite and semifusinite fractions, respectively. Me groups account for greater proportions of the aliphatic carbon with increasing density. With the variations evident in random reflectance these structural trends are consistent.
Reduction and reductive alkylatlon of coals using 99100076 deuterlum containing compounds Kozlowski, M. and Wachowska, H. Fuel, 1998, 77, (6) 591-599. In the system potassium/liquid ammonia two Polish coals are subjected to the reactions of reduction and reductive alkylation. The classical methods of reduction and reductive alkylation of coal are modified by replacing the conventional protonating and alkylating agents by the ones containing deuterium atoms. Reduction is performed with CzH50D whereas reductive alkylation uses CD31. Fragmentation of the coal structure proceeds mainly by cleavage of methylene bridges. The products of reactions of both kinds are subjected to extraction with dichloromethane. The yield of extraction of the modified coals is significantly greater than that of raw coals. Average molar weights of the extracts are determined and elemental and spectral analyses of the raw materials and products are performed. Also discussed is the effect of the kind of hydrogen isotope in the modifying agents on the results obtained. 99160077
The regional biomass-energy agency (ERBE): an opportunity for the biomass-energy development In Wallonla
Lemaire, Mater..
P. ert al. Making Bus. Biomass Energy, Environ., Chemical, Fibers Edited by Proc. Biomass Confi Am. 3rd, 1997, (2), 1515-1523.
Overend, R. P. and Chornet, E. In 1995, a biomass-energy agency (ERBE) was set up by the European Commission (Directorate-General for Energy) and the Walloon government to promote and build biomass-energy projects in Wallonia (Belgium). A survey of biomass-energy potential indicates that wood-energy seems to offer the best utilization opportunities. Forest and logging residues, sawmills’ and joineries’ off-cuts, pallets residues, etc. could be burnt in wood district heating units with a significant social benefit. Consequently, the ERBE Agency is trying to set up projects in this way as in Austria or in Sweden. It serves to inform industries and municipalities about biomassenergy, to advise them in the building of biomass-energy projects, to identity their energy needs and their biomass resources, to carry out prefeasibility studies, to inform them about financing opportunities, and so on. 99100076
Regression analysis of the composition and properties of macerals of Kuznetsk Basin coals with different degrees of reduction Gagarin, S. G. Woks Khim., 1998, (2) 2-6. (In Russian) Determined is the correlation between the H/C ratio and volatile matter content of vitrinite and inertinite Kuznetsk Basin coals with different degrees of reduction.
Research on agglomeration In a coal gaslfler with 99/00079 twin fluldized beds Xiong, Y. et al.
Proc. Annu. Int. PiUsburgh Coal Conf, 1997, 14, (20), 16-
22.
In this paper agglomeration of bed material in coal gasification with twin fluidized beds is studied. Optical microscope, X-ray diffraction, and thermal analyses of agglomerates were carried out and the mechanism of agglomeration and bed defluidization were discussed.
Scenarios for power production with biomass in the Finnish forest Industry
QQ/QQQ60 Nousiamen,
I. K. et al.
Making Bus. Biomoss Energy, Environ., Fibers Mater., Proc. Biomass Conf. Am. 3rd, 1997, (2), 1345-1351.
Chemical,
Edited by Overend, R. P. and Chornet, E. Presented in this study are three scenarios for power production with biomass in Finnish pulp and paper mills. The basic scenario assumes that the production capacity in the forest industry increases as in the past. The green energy scenario assumes that there is a strong demand from the market for sustainable green energy production. The maximum scenario assumes that the production capacity of chemical pulp increases significantly and the use of wood raw material extends to the maximum level. According to the basic scenario the use of biofuels in the pulp and paper mills will increase from starting level, 3.24 Mtoe in 1992, to 5.07 Mtoe by
Solid
fuels
(sources,
winning,
propedies)
the year 2010. The utilization potential of biofuels will increase to 5.45 Mtoe in green energy and to 6.43 Mtoe in the maximum biofuels scenario. The power production with biomass will increase from the starting level, 572 MW in 1992, to 930 MW in the basic, to 1100 MW in the green energy and to 1670 MW in the maximum biofuels scenario by the year 2010. 9QlclQct61
Separation of fossil resin from northeast China
coal Xie, H. et al. Proc. Annu. Int. Piftsburgh Cool Conf., 1997, 14, (6). 15-23. In China some coal fields contain macroscopic fossil resins, but these fossil resins have not been recovered commercially. The distribution of fossil resin in coal from north-east China was characterized before recovering it by flotation and gravity separation. The fossil resin particles whose weight accounted for more than 99% of all fossil resin in the sample were larger than 0.125 mm. A concentrated product that contained almost 100% fossil resin at a recovery of more than 88% was obtained from a feed containing 1.72% fossil resin using a shaking table followed by float-sink separation with a sodium chloride solution (1.1 g/ml). By conventional single stage flotation, a fossil resin concentrate containing 48% fossil resin at a recovery of 95% was obtained from a feed containing 11.4% fossil resin. The grade of the concentrate was increased to a certain extent by treating the feed with Hz02 solution before flotation, but the recovery of fossil resin decreased greatly.
Shrlnkin -bed model for percolation process applled to dilute-ac 9d pretreatment/hydrolysis of cellulosic biomass
QQlQQQ62
Chen, R. et al. Appl. Biochemical Biotechnol., 1998, (70-72), 37-49. Hemicellulose is biphasic upon dilutive-acid hydrolysis for many lignocellulosic substrates, which leads to a modified percolation process employing simulated two-stage reverse-flow. This process has been proven to attain substantially higher sugar yields and concentrations over the single-stage percolation process.The dilutive-acid pretreatment of biomass solubilizes the hemicellulose fraction in the solid biomass, leaving less solid biomass in the reactor and reducing the bed. Therefore, a bed-shrinking mathematic kinetic model was developed to describe the two-stage reverseflow reactor operated for hydrolysing biphasic substrates, including hemicellulose, in corn cob/stover mixture (CCSM). The simulation indicates that the shrinking-bed operation increases the sugar yield by about 5%, compared to the non-shrinking bed operation in which 1 reactor volume of liquid passes through the reactor. A simulated optimal run further revealed that the fast portion of hemicellulose was almost completely hydrolysed in the first stage, and the slow portion of hemicellulose was hydrolysed in the second stage. Under optimal conditions, the bed shrank 27%, and a sugar yield over 95% was attained.
Slagging and fluidity behavior of coal ash under gaslfler environment
99lOQ663
Kim, H. T. et al. Proc. Annu. Int. Pinsburgh Coal Conf., 1997, 14, (26), l-11. In this study the objective is to predict the slagging and fluidity behaviour of coal ashes from the physical/chemical properties of parent coals to determine the optimum operating parameter of slagging-type coal gasifier. Three types of coal samples, such as Alaska Usibelli, China Datong and Posco (blended coal), were analysed for their ash composition and ash fusion temperature. Optimum quantity of CaO addition is evaluated with considering negative effect of CaO addition on gasification reaction to investigate the effect of flux addition on ash slagging behaviour. The effect of blending of Posco coal with Alaska and Datong coal on ash slagging is also investigated to expand the variety and performance of coal types in slagging-type entrained-bed gasifier. The results of the experiment show that the optimum CaO fluxing quantity is 10%. 20% on Alaska and Dating coal, respectively. However, optimum blending ratio for ash slagging is not found when mixing Posco coal with Alaska or Datong coals. Melting and slagging characteristics of coal ash samples with changing temperature were examined in detail by DTA. ASTM ash melting temperatures as well as critical viscosity temperature are compared with TGA and DTA profiles. DTA experiments illustrate that coal ash starts to melt before the IDT (initial deformation temperature) and that theoretical T,, (critical viscosity temperature) is well correlated with DTA profile. Experiment of ash fluidity were also carried on with the Alaska and Datong coal ashes using a high temperature viscometer. The experimental viscosity data was compared with the calculated viscosity and results show good correlation. As a result, viscosity of coal ash could be calculated with Watt and Fereday equation in high temperature range. QQlOOO64
Slovak brown coal characterization caustic leaching
after molten
Balaz, P. et al. Proc. Annu. Int. Pittsburgh Cool Conf., 1997, 14, (7). 16-26. Leaching of Slovak brown coal with molten sodium hydroxide at 380” for 20 min decreases its sulfur content from 3.26 to 0.26 wt%. QQlOOO65
Solvent swelling rates of low rank coals and lmpllcatlons regarding their structure
Otake, Y. and Suuberg, Eric M. Fuel, 1998, 77, (8) 901-904. Low rank US coals have been measured, the rates of solvent swelling of a suite in various organic solvents at various temperatures. The equilibrium extents of swelling are independent of temperature within the temperature range studied (25-70°C). The rate of the swelling process was generally
Fuel and Energy Abstracts
January 1999 9