- Email: [email protected]
00609 Study on pelletizing of modified coal gangue by microwave radiation
01 Solid fuels (preparation) separating the flocculated basis. With the Hydrofloat was obtained with a 90%
coal from the dispersed ash on a continuous separator, a clean coal containing 14% ash combustible recovery.
04100609 Study on pelietiring microwave radiation
of modified
coal gangue
by
Zhao, Z. and He, T. Huagong Kuangwu Yu &gong, 2003, 32, (I), 2122. (In Chinese) According to the characteristics of selectivity of microwave, the useful minerals and oxides in modified coal gangue was radiated by microwave to heat indirectly the mineral composition which couldn’t adsorb microwave such as silicon dioxide. It would make these mineral compositions to change crystal structure and phase, and finally finish sintering process of coal gangue.
04/00610 Thermal behaviour rank perhydrous coals
during
the pyrolysis
of low
Arenillas, A. et al. Journal of Analytical and Applied Pyrolysis, 2003. 68-69, 371-385. Perhydrous coals are characterized by high H/C atomic ratios and so their chemical structure is substantially modified with respect to that of conventional coals. As a result, perhydrous coals show different physico-chemical properties to common coals (i.e. higher volatile matter content, enhancement of oil/tar potential, relatively lower porosity and higher fluidity during carbonization). However, there is little information about thermal behaviour during the pyrolysis of this type of coal. In this work, six perhydrous coals (H/C ratio between 0.83 and 1.07) were pyrolysed and analysed by simultaneous thermogravimetry/mass spectrometry. The results of this work have revealed the influence of high H/C values on the thermal behaviour of the coals studied. During pyrolysis the perhydrous coals exhibit very well defined symmetrical peaks in the mass loss rate profiles, while normal coals usually show a broader peak. The shape of such curves suggests that in perhydrous coals fragmentation processes prevailed over condensation reactions. The high hydrogen content of perhydrous coals may stabilize the free radicals formed during heat treatment, increasing the production of light components.
Preparation 04100611 Biodesuiphurization physical cleaning of coal
as a complement
to the
Martinez, 0. et al. Fuel, 2003, 82, (9), 1085-1090. Physical and biological processes have been combined with a view to reduce the sulphur and ash content of finely ground coal. The coal used was a semianthracite from the North Spain Coal Field. A sample of several kg in a coal/water suspension with a w/w concentration of 15% was subjected to a physical treatment combining cyclone and flotation separation processes. Representative samples were taken from each of five size fractions: original feed and the physical separation products, which were screened through water into sub-samples classified by particle size. Each fraction from the physical separation and the screening was analysed for ash and sulphur. The elimination yield of the hydrocyclone was 22% of ash and 21% of sulphur. The figure for ash raised to 41% when the hydrocyclone and flotation equipment were both used, with no change in sulphur elimination. In turn, the biodesulphurization treatment applied in addition to the two processes raised the respective yields to 59 and 42%. The change in the calorific value of the coal was hardly significant, while sulphur emissions, expressed as g S/GJ were reduced by 51%. Additionally, an assessment was made of the thermal behaviour of the various samples from the physical and biological treatment by means of programmed temperature combustion analysis carried out by a thermogravimetric equipment.
04/00612 Coprocessing Yanzhou for preparing paying asphalt
coal with petroleum
resid
Wang, Z. et al. Zhongguo Kuangye Dame Xuehao. 2003, 32, (l), 48-52. (In Chinese) Coprocessing of Yanzhou coal with five types of petroleum resid (slurry) for preparing high-grade paving asphalt (HGPA) was investigated in an autoclave. The asphalt obtained was evaluated by three indexes (penetration, softening point and ductility). Thin-layer chromatographic (TLC) and NMR were used to characterize the asphalt. The result shows that the properties of resid are crucial for the quality of asphalt derived. Under experimental conditions, only coprocessing of coal with SLH slurry, which has lower H/C ratio, higher aromatics content and shorter aliphatic side-chain than that of the other four resids, can produce qualified asphalt, and meet the specification of HGPA of China in three main properties. Under
experimental conditions, a higher Hz pressure can increase asphalt yield, but higher ratio of coal to resid (slurry) can lower the quality of asphalt.
04/00613 high-sulfur
Demineraiization and desuifurization Assam coal with alkali treatment
of
Mukherjee, S. Energy & Fuels, 2003. 17, (3), 559-564. Demineralization and desulfurization of high-sulfur coal from Assam (Makum coalfield), India, were investigated using aqueous solutions of sodium hydroxide, potassium hydroxide, and their mixtures. (1: 1) alone as well as followed by mild hydrochloric acid treatment. Compared to the alkali and acid alone, successive treatments with the alkali and acid resulted in significant removal of mineral matter and sulfur from the coal. Demineralization and desulfurization were found to increase with the increase in alkali concentration. Alkali treatment resulted in formation and proportion of sodium/potassium aluminosilicates, which subsequently undergo decomposition and solubilization in the presence of acid-forming soluble salts. It is possible to remove 50-54% of the ash, total inorganic sulfur, and around 25% organic sulfur from the coal by treatment with mixtures (1:l) of 16% sodium hydroxide and potassium hydroxide solution followed by 10% hydrochloric acid.
04/00614 reburning
Experiments on low-volatile for NO reduction
bituminous
coal
Gao, Z.-Y. et al. Huahei Dianli Da-me Xuehao. 2003. 30, (I), 41-44. (In Chinese) A low volatile bituminous coal was used as reburn fuel. Experiments were carried out in an entrained flow reactor to investigate the NO reduction rate. The results indicate the NO reduction rates are strongly dependent on the reaction time, the coal particle size and the reburn fuel fraction. Increased reaction time, smaller coal particle size and increased reburn fuel fraction lead to higher NO reduction rate.
04/00615 extraction
influence of pretreatment of some Turkish iignites
on solvent-swelling
and
Onal, Y. and Akol, S. Fuel, 2003, 82. (1 l), 1297-1304. In this study, three Turkish lignites (Beypazar (LGN-l), Golba (LGN2) and Kangal (LGN-3)) have been pre-treated with the solutions of O.lN HCl, 10% HCI, HCI-HF or with air oxidation at 200°C. Swelling ratios of original and pre-treated lignites have been determined by using 11 different solvents. Original and pretreated samples have been subjected to pre-swollen by using THF at room temperature. Toluene Soxhlet extraction experiments of these and unswollen samples have been also carried out. The effect of solvent swelling ratio on the extraction yields of the original and pre-treated lignites have been examined. The results showed that the swelling ratios were high in hydrogen bonding solvents but low in non-hydrogen bonding solvents. It is found that the best solvent is 2-ethanolamine and second is pyridine for these Iignites. The pre-treatment increased the swelling values of the lignites by all solvents. Comparing with original lignites in all solvents except pyridine and 2-ethanolamine, the swelling values were not changed by oxidation. The results have indicated that both swelling and extraction yields generally increased after the pretreatments and the increments are higher with hydrogen bonding solvents.
04/00616 Treating freeze-binding
coal and other piled materials
to inhibit
Smith, K. W. and Stanley, M. E. et al. U.S. US 6,569,348 (Cl. 252-70; C09K3/18), 27 May 2003, US Appl. 943,998. Coal and other piles of particulates exposed to the weather are inhibited from freezing by treating them with potassium formate or potassium formate aqueous solutions. A viscosifier in the amount of 0.001-5 wt%, preferably 0.01-3 wt%, is used to retain the solution in the interstices and voids between the particulates, inhibiting drainage and waste of the solution. Corrosion inhibitors in the amount of 0.51-5 wt% are also compatible with the solution.
04/00617 Treatment of wastewaters from dewatering process of brown coal by use of a novel Ni-supported carbon catalyst Nakagawa,
H.
et al. Preprints of S.vmposia of Fuel Chemistry, 2003, 48, (l),
American
Chemical
464-465. A non-evaporating drying process is preferable for dewatering of brown coals prior to use for power generation. Simultaneously, a large amount of wastewater containing organic compounds derived from brown coal is discharged from the dewatering process. In this paper a brown coal was treated under the hydrothermal conditions for dewatering and a new Ni-supported carbon (carbonized polymethacrylate resin Diaion WK 11) catalyst was applied to gasify the wastewater emitted during the dewatering by converting small molecule weight organic compounds to convert them to CH4, with smaller amounts of CO* and HZ. Organic compounds water-soluble lignin, m-cresol, and phenol were also gasified for comparison. Low molecule weight wastewater compounds are more reactive than high Society,
Division
Fuel
and
Energy
Abstracts
March 2004
63
coal from the dispersed ash on a continuous separator, a clean coal containing 14% ash combustible recovery.
04100609 Study on pelietiring microwave radiation
of modified
coal gangue
by
Zhao, Z. and He, T. Huagong Kuangwu Yu &gong, 2003, 32, (I), 2122. (In Chinese) According to the characteristics of selectivity of microwave, the useful minerals and oxides in modified coal gangue was radiated by microwave to heat indirectly the mineral composition which couldn’t adsorb microwave such as silicon dioxide. It would make these mineral compositions to change crystal structure and phase, and finally finish sintering process of coal gangue.
04/00610 Thermal behaviour rank perhydrous coals
during
the pyrolysis
of low
Arenillas, A. et al. Journal of Analytical and Applied Pyrolysis, 2003. 68-69, 371-385. Perhydrous coals are characterized by high H/C atomic ratios and so their chemical structure is substantially modified with respect to that of conventional coals. As a result, perhydrous coals show different physico-chemical properties to common coals (i.e. higher volatile matter content, enhancement of oil/tar potential, relatively lower porosity and higher fluidity during carbonization). However, there is little information about thermal behaviour during the pyrolysis of this type of coal. In this work, six perhydrous coals (H/C ratio between 0.83 and 1.07) were pyrolysed and analysed by simultaneous thermogravimetry/mass spectrometry. The results of this work have revealed the influence of high H/C values on the thermal behaviour of the coals studied. During pyrolysis the perhydrous coals exhibit very well defined symmetrical peaks in the mass loss rate profiles, while normal coals usually show a broader peak. The shape of such curves suggests that in perhydrous coals fragmentation processes prevailed over condensation reactions. The high hydrogen content of perhydrous coals may stabilize the free radicals formed during heat treatment, increasing the production of light components.
Preparation 04100611 Biodesuiphurization physical cleaning of coal
as a complement
to the
Martinez, 0. et al. Fuel, 2003, 82, (9), 1085-1090. Physical and biological processes have been combined with a view to reduce the sulphur and ash content of finely ground coal. The coal used was a semianthracite from the North Spain Coal Field. A sample of several kg in a coal/water suspension with a w/w concentration of 15% was subjected to a physical treatment combining cyclone and flotation separation processes. Representative samples were taken from each of five size fractions: original feed and the physical separation products, which were screened through water into sub-samples classified by particle size. Each fraction from the physical separation and the screening was analysed for ash and sulphur. The elimination yield of the hydrocyclone was 22% of ash and 21% of sulphur. The figure for ash raised to 41% when the hydrocyclone and flotation equipment were both used, with no change in sulphur elimination. In turn, the biodesulphurization treatment applied in addition to the two processes raised the respective yields to 59 and 42%. The change in the calorific value of the coal was hardly significant, while sulphur emissions, expressed as g S/GJ were reduced by 51%. Additionally, an assessment was made of the thermal behaviour of the various samples from the physical and biological treatment by means of programmed temperature combustion analysis carried out by a thermogravimetric equipment.
04/00612 Coprocessing Yanzhou for preparing paying asphalt
coal with petroleum
resid
Wang, Z. et al. Zhongguo Kuangye Dame Xuehao. 2003, 32, (l), 48-52. (In Chinese) Coprocessing of Yanzhou coal with five types of petroleum resid (slurry) for preparing high-grade paving asphalt (HGPA) was investigated in an autoclave. The asphalt obtained was evaluated by three indexes (penetration, softening point and ductility). Thin-layer chromatographic (TLC) and NMR were used to characterize the asphalt. The result shows that the properties of resid are crucial for the quality of asphalt derived. Under experimental conditions, only coprocessing of coal with SLH slurry, which has lower H/C ratio, higher aromatics content and shorter aliphatic side-chain than that of the other four resids, can produce qualified asphalt, and meet the specification of HGPA of China in three main properties. Under
experimental conditions, a higher Hz pressure can increase asphalt yield, but higher ratio of coal to resid (slurry) can lower the quality of asphalt.
04/00613 high-sulfur
Demineraiization and desuifurization Assam coal with alkali treatment
of
Mukherjee, S. Energy & Fuels, 2003. 17, (3), 559-564. Demineralization and desulfurization of high-sulfur coal from Assam (Makum coalfield), India, were investigated using aqueous solutions of sodium hydroxide, potassium hydroxide, and their mixtures. (1: 1) alone as well as followed by mild hydrochloric acid treatment. Compared to the alkali and acid alone, successive treatments with the alkali and acid resulted in significant removal of mineral matter and sulfur from the coal. Demineralization and desulfurization were found to increase with the increase in alkali concentration. Alkali treatment resulted in formation and proportion of sodium/potassium aluminosilicates, which subsequently undergo decomposition and solubilization in the presence of acid-forming soluble salts. It is possible to remove 50-54% of the ash, total inorganic sulfur, and around 25% organic sulfur from the coal by treatment with mixtures (1:l) of 16% sodium hydroxide and potassium hydroxide solution followed by 10% hydrochloric acid.
04/00614 reburning
Experiments on low-volatile for NO reduction
bituminous
coal
Gao, Z.-Y. et al. Huahei Dianli Da-me Xuehao. 2003. 30, (I), 41-44. (In Chinese) A low volatile bituminous coal was used as reburn fuel. Experiments were carried out in an entrained flow reactor to investigate the NO reduction rate. The results indicate the NO reduction rates are strongly dependent on the reaction time, the coal particle size and the reburn fuel fraction. Increased reaction time, smaller coal particle size and increased reburn fuel fraction lead to higher NO reduction rate.
04/00615 extraction
influence of pretreatment of some Turkish iignites
on solvent-swelling
and
Onal, Y. and Akol, S. Fuel, 2003, 82. (1 l), 1297-1304. In this study, three Turkish lignites (Beypazar (LGN-l), Golba (LGN2) and Kangal (LGN-3)) have been pre-treated with the solutions of O.lN HCl, 10% HCI, HCI-HF or with air oxidation at 200°C. Swelling ratios of original and pre-treated lignites have been determined by using 11 different solvents. Original and pretreated samples have been subjected to pre-swollen by using THF at room temperature. Toluene Soxhlet extraction experiments of these and unswollen samples have been also carried out. The effect of solvent swelling ratio on the extraction yields of the original and pre-treated lignites have been examined. The results showed that the swelling ratios were high in hydrogen bonding solvents but low in non-hydrogen bonding solvents. It is found that the best solvent is 2-ethanolamine and second is pyridine for these Iignites. The pre-treatment increased the swelling values of the lignites by all solvents. Comparing with original lignites in all solvents except pyridine and 2-ethanolamine, the swelling values were not changed by oxidation. The results have indicated that both swelling and extraction yields generally increased after the pretreatments and the increments are higher with hydrogen bonding solvents.
04/00616 Treating freeze-binding
coal and other piled materials
to inhibit
Smith, K. W. and Stanley, M. E. et al. U.S. US 6,569,348 (Cl. 252-70; C09K3/18), 27 May 2003, US Appl. 943,998. Coal and other piles of particulates exposed to the weather are inhibited from freezing by treating them with potassium formate or potassium formate aqueous solutions. A viscosifier in the amount of 0.001-5 wt%, preferably 0.01-3 wt%, is used to retain the solution in the interstices and voids between the particulates, inhibiting drainage and waste of the solution. Corrosion inhibitors in the amount of 0.51-5 wt% are also compatible with the solution.
04/00617 Treatment of wastewaters from dewatering process of brown coal by use of a novel Ni-supported carbon catalyst Nakagawa,
H.
et al. Preprints of S.vmposia of Fuel Chemistry, 2003, 48, (l),
American
Chemical
464-465. A non-evaporating drying process is preferable for dewatering of brown coals prior to use for power generation. Simultaneously, a large amount of wastewater containing organic compounds derived from brown coal is discharged from the dewatering process. In this paper a brown coal was treated under the hydrothermal conditions for dewatering and a new Ni-supported carbon (carbonized polymethacrylate resin Diaion WK 11) catalyst was applied to gasify the wastewater emitted during the dewatering by converting small molecule weight organic compounds to convert them to CH4, with smaller amounts of CO* and HZ. Organic compounds water-soluble lignin, m-cresol, and phenol were also gasified for comparison. Low molecule weight wastewater compounds are more reactive than high Society,
Division
Fuel
and
Energy
Abstracts
March 2004
63