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03592 Alternative fuels from slurry ponds
01 The US department of energy’s combustion 97103589 program: clean, efficient electricity from coal
2000
Ruth, L. A. Enem Comers. Mgmt, 1997, 38, (IO-13) Joint work between the United States Department of Energy’s Pittsburgh Energy Technology Center, under its Combustion 2000 program, and private industry has been undertaken. The objective is the development of two kinds of advanced, coal-fired electric power generation systems that will have significantly higher thermal efficiency, superior environmental performance and a lower cost of electricity than current coal-fired plants. The low emission boiler system (LEBS) is a highly advanced pulverizedcoal-fired power plant which will be ready for commercial introduction before the year 2001. It uses supercritical steam conditions and substantial low-level heat recovery to achieve an efficiency of 42% and advanced combustion technology and pollution controls that are integrated with the boiler to produce very low emissions. The high performance power system (HIPPS) is based on indirectly fired combined-cycle technology that is capable of 47-50% efficiency. This system uses a gas turbine driven by a clean air working fluid separately heated in a novel high-temperature furnace and should be commercially available by 2005.
Utilization of Indonesia’s 97103590 tial, challenges and prospects
low rank coal: its poten-
Panaka, P. Proc. Inl. Tech. Conf: Coal Ufil. Fuel Syst., 1997, 22. 37-46. About 36 billion tons of coal resources potential in Indonesia, however over 21 billion tons (58.7%) is classified as low-rank (lignite) coal. Due to their properties, these coals are not economical to be transported for a long distance and are therefore unexportable and consequently under-utilized at present. The utilization of low-rank coals is expected to grow in importance as the domestic demand for energy increases. Investigations into possible upgrading technology for low-rank coals by reducing the total moisture of it are necessary and then those coals can be converted into coal water mixture, coal liquefaction, gasification, briquetting, etc. Low conversion efficiency resulting from the high moisture content and relatively low calorific value, the risk of spontaneous combustion, ash deposit formation and higher CO? emission are some of the problems associated with lowrank coals. The adoption of new and advanced technologies for their utilization is therefore required. Combined cycle technologies combined with coal upgrading technology are applicable to low-rank coals and are expected to be implemented in a major type of future power plant for Indonesia. The main question is whether these plants can be competitive when the extra costs involved in up-grading the coal are considered.
Derived
97103591 coal chars
Solid Fuels
Activation
energy
for the oxidation
of Malaysian
Haji-Sulaiman, M. 2. and Aroua, M. K. .I. of Institute of Energy, June 1997, 70, 52-56. A thermal gravimetric analyser (TGA) was used to study the oxidation of two Malaysian coal chars. The weight-loss data were analysed by the temperature program reaction (TPR) technique, which employed the random pore model of Bhatia & Perlmutter. All experiments were conducted within a temperature range of 698-773 K (isothermal condition) and heating rates of 2-10 K min- ’(dynamic condition) with char samples in the size range 53-75 I’m. It was found that the random pore model can accurately describe the oxidation of char to yield activation energy that is similar to that obtained from model free kinetics, provided the structural parameter v’, which is an input to the model, is taken as an adjustable parameter.
97103592
Alternative
fuels from slurry ponds
Harrison, C. D. et al. Proc. Int. Tech. ConJ Coal Ufil. Fuel Syst., 1997, 22, 141-148. There exist a number of options for use of coal fines from active and abandoned slurry ponds delivered to power stations separate: they can be handled as-received, pelletized, used to produce composite fuel, or fired as a coal water slurry.
97103593
AMAX-HiCal
briquetting
project
Woessner, P. W. and Wilbur, J. T. Proc. Int. Tech. Conj Coal Util. Fuel Syst., 1993, 18, 83-94. A single process for drying and briquetting coal is studied. The HiCal briquetting process produces briquetted fuel with a moisture content of 7.5% and a heating value of 11,200 BTU/lb. This low sulfur briquetted fuel has a sulfur content of 0.43% which produced an emission rate of less than 0.8 lb of SO, per million BTU. Power production efficiency is enhanced by its high calorific value and low moisture content, while overall plant emission is reduced. Research shows this fuel can be produced economically.
97103594 Sriquetlng types of coal
So/id
fuels
as an upgrading
(derived
process
so/id
fuels)
for different
Wolfgang; G. H. Proc. Int. Tech. Conf. Coal Util. Fuel Syst., 1994, 19. 1X1195. The briquetting process has had an important role in many countries in the upgrading of different types of coal. Improved shape and size of briquetted coal is one of the advantages, along with improved heating value, water resistance, thermal shock resistance, transport and storage characteristics. In many cases coal is also dried in connection with briquetting. A survey of technologies which are available for binderless briquetting of lignite and sub-bituminous coal as well as for briquetting with binders of subbituminous and bituminous coal or anthracite is presented.
97103595
Carbonization
furnace
Nakada, K. and Abe, T. Jpn. Kokai Tokkyo Koho JP 09 95,676 [97 95,676] (Cl. ClOBS3iOO). 8 Apr 1997, Appl. 951252,462, 29 Sep 1995, 6 pp. (In Japanese) The paper describes a carbonization furnace for combustible-containing materials or inorganic binder-coated combustibles as raw materials. Comprising a feeding inlet on one side of a cylindrical furnace and a discharge outlet on the other side of the furnace, the raw materials are ignited on the opposite direction of the feeding direction and carbonized on the discharge outlet side of the furnace.
Development of coke strength and its relation to the porous structure
97103598
during carbonization
Sato, H. et al. Jubilee Res. Event, Two-Day Svmp., 1997, I. l-4. Coke strength development was studied during carbonization to elucidate fissure formation phenomena, which affect size distribution of the final product. Cokes were made under various heating conditions to find a parameter which would relate to strength development under different heating conditions. The fraction of the pyrolysis reaction was defined with regard to the effect of temperature history. This parameter was more effective than the carbonization temperature since it is a better representation of the extent of the coke structure change during carbonization. Using the parameter an estimate was made of the effect of temperature history on strength development during carbonization in the commercial coke oven. The effect of the porous structure of coke on the tensile strength was also investigated. Tensile strength was revealed to be markedly dependent on the pore orientation.
97103597 petroleum
The coke
effect
of grinding
on
the
sintering
of raw
Cheng, H. M. et al. Carbon, 1997, 35, (7). 869-874. Dense carbon materials were prepared without the use of any binder. The effect of grinding treatment on the characteristics of raw petroleum needle coke and on the properties of the sintered carbon compacts was investigated, and the sintering mechanism of the coke after grinding was discussed. Coke particle size and crystalline size decreased and the specific surface area of the coke increased with grinding, with obvious influence for up to 20 h grinding treatment. The interlayer spacing of the coke after graphitization at 2773 K was gradually increased and the a-axis constant was marginally reduced with the grinding time. Results from the sintering experiment show that carbon materials can be sintered from the ground coke and this ability was considered to result from the increase of surface energy, lattice distortion energy and fraction of volatile matters of the coke, which were induced by grinding treatment.
97103598 Expansion of delayed coker capacity Ou, S. Lianyou S’heji, 1997, 27, (I), 1-4. (In Chinese) Introduces the situation of I9 domestic operating delayed cokers. Potentialities of the main equipment of delayed cokers including the heaters, coking drums and fractionators were analysed. Measures for extending the processing capacity of the units such as lowering the recycle ratio, deeply distilling residue oil, reducing injection water amount into heater tubes and shortening coking cycle etc. were proposed.
97103599 Externally coking of coal
heated
retort
apparatus
suitable
for
Calderon, A. US 5,639,353 (Cl. 201-15; ClOB47/00), 17 Jun 1997, US Appl. 336,399, 9 Nov 1994, 5 pp. In this apparatus, the tubular retort is equipped with an elongated coking chamber with external heating and thermally conductive walls. It also has a charging mechanism for the feed of granular coal (or a similar material) into the chamber, removal of hot gas for collection, and the associated discharge of hot coke from the other chamber end into a quenching zone. The high-conductivity wall tiles are preferably manufactured from sintered SIC or SijNj-bonded SIC, and are installed in the coking zone of the otherwise thermally insulated retort. The hot gas from coking is collected and processed for cracking and pollution control.
97103600 Fundamental of bio-briquets
study on combustion
characteristics
Lu, G.-Q. et al. Kagoku Kogaku Ronbunshu, 1997, 23, (3), 404-412. (In Japanese) A study of pyrolysis and combustion characteristics of bio-briquettes were studied using an electrically heated batch combustor. The influences of biomass content of the bio-briquette on its combustion characteristics obtained by measuring the fuel consumption profile and the experimental
Fuel and Energy Abstracts
September
1997
303
2000
Ruth, L. A. Enem Comers. Mgmt, 1997, 38, (IO-13) Joint work between the United States Department of Energy’s Pittsburgh Energy Technology Center, under its Combustion 2000 program, and private industry has been undertaken. The objective is the development of two kinds of advanced, coal-fired electric power generation systems that will have significantly higher thermal efficiency, superior environmental performance and a lower cost of electricity than current coal-fired plants. The low emission boiler system (LEBS) is a highly advanced pulverizedcoal-fired power plant which will be ready for commercial introduction before the year 2001. It uses supercritical steam conditions and substantial low-level heat recovery to achieve an efficiency of 42% and advanced combustion technology and pollution controls that are integrated with the boiler to produce very low emissions. The high performance power system (HIPPS) is based on indirectly fired combined-cycle technology that is capable of 47-50% efficiency. This system uses a gas turbine driven by a clean air working fluid separately heated in a novel high-temperature furnace and should be commercially available by 2005.
Utilization of Indonesia’s 97103590 tial, challenges and prospects
low rank coal: its poten-
Panaka, P. Proc. Inl. Tech. Conf: Coal Ufil. Fuel Syst., 1997, 22. 37-46. About 36 billion tons of coal resources potential in Indonesia, however over 21 billion tons (58.7%) is classified as low-rank (lignite) coal. Due to their properties, these coals are not economical to be transported for a long distance and are therefore unexportable and consequently under-utilized at present. The utilization of low-rank coals is expected to grow in importance as the domestic demand for energy increases. Investigations into possible upgrading technology for low-rank coals by reducing the total moisture of it are necessary and then those coals can be converted into coal water mixture, coal liquefaction, gasification, briquetting, etc. Low conversion efficiency resulting from the high moisture content and relatively low calorific value, the risk of spontaneous combustion, ash deposit formation and higher CO? emission are some of the problems associated with lowrank coals. The adoption of new and advanced technologies for their utilization is therefore required. Combined cycle technologies combined with coal upgrading technology are applicable to low-rank coals and are expected to be implemented in a major type of future power plant for Indonesia. The main question is whether these plants can be competitive when the extra costs involved in up-grading the coal are considered.
Derived
97103591 coal chars
Solid Fuels
Activation
energy
for the oxidation
of Malaysian
Haji-Sulaiman, M. 2. and Aroua, M. K. .I. of Institute of Energy, June 1997, 70, 52-56. A thermal gravimetric analyser (TGA) was used to study the oxidation of two Malaysian coal chars. The weight-loss data were analysed by the temperature program reaction (TPR) technique, which employed the random pore model of Bhatia & Perlmutter. All experiments were conducted within a temperature range of 698-773 K (isothermal condition) and heating rates of 2-10 K min- ’(dynamic condition) with char samples in the size range 53-75 I’m. It was found that the random pore model can accurately describe the oxidation of char to yield activation energy that is similar to that obtained from model free kinetics, provided the structural parameter v’, which is an input to the model, is taken as an adjustable parameter.
97103592
Alternative
fuels from slurry ponds
Harrison, C. D. et al. Proc. Int. Tech. ConJ Coal Ufil. Fuel Syst., 1997, 22, 141-148. There exist a number of options for use of coal fines from active and abandoned slurry ponds delivered to power stations separate: they can be handled as-received, pelletized, used to produce composite fuel, or fired as a coal water slurry.
97103593
AMAX-HiCal
briquetting
project
Woessner, P. W. and Wilbur, J. T. Proc. Int. Tech. Conj Coal Util. Fuel Syst., 1993, 18, 83-94. A single process for drying and briquetting coal is studied. The HiCal briquetting process produces briquetted fuel with a moisture content of 7.5% and a heating value of 11,200 BTU/lb. This low sulfur briquetted fuel has a sulfur content of 0.43% which produced an emission rate of less than 0.8 lb of SO, per million BTU. Power production efficiency is enhanced by its high calorific value and low moisture content, while overall plant emission is reduced. Research shows this fuel can be produced economically.
97103594 Sriquetlng types of coal
So/id
fuels
as an upgrading
(derived
process
so/id
fuels)
for different
Wolfgang; G. H. Proc. Int. Tech. Conf. Coal Util. Fuel Syst., 1994, 19. 1X1195. The briquetting process has had an important role in many countries in the upgrading of different types of coal. Improved shape and size of briquetted coal is one of the advantages, along with improved heating value, water resistance, thermal shock resistance, transport and storage characteristics. In many cases coal is also dried in connection with briquetting. A survey of technologies which are available for binderless briquetting of lignite and sub-bituminous coal as well as for briquetting with binders of subbituminous and bituminous coal or anthracite is presented.
97103595
Carbonization
furnace
Nakada, K. and Abe, T. Jpn. Kokai Tokkyo Koho JP 09 95,676 [97 95,676] (Cl. ClOBS3iOO). 8 Apr 1997, Appl. 951252,462, 29 Sep 1995, 6 pp. (In Japanese) The paper describes a carbonization furnace for combustible-containing materials or inorganic binder-coated combustibles as raw materials. Comprising a feeding inlet on one side of a cylindrical furnace and a discharge outlet on the other side of the furnace, the raw materials are ignited on the opposite direction of the feeding direction and carbonized on the discharge outlet side of the furnace.
Development of coke strength and its relation to the porous structure
97103598
during carbonization
Sato, H. et al. Jubilee Res. Event, Two-Day Svmp., 1997, I. l-4. Coke strength development was studied during carbonization to elucidate fissure formation phenomena, which affect size distribution of the final product. Cokes were made under various heating conditions to find a parameter which would relate to strength development under different heating conditions. The fraction of the pyrolysis reaction was defined with regard to the effect of temperature history. This parameter was more effective than the carbonization temperature since it is a better representation of the extent of the coke structure change during carbonization. Using the parameter an estimate was made of the effect of temperature history on strength development during carbonization in the commercial coke oven. The effect of the porous structure of coke on the tensile strength was also investigated. Tensile strength was revealed to be markedly dependent on the pore orientation.
97103597 petroleum
The coke
effect
of grinding
on
the
sintering
of raw
Cheng, H. M. et al. Carbon, 1997, 35, (7). 869-874. Dense carbon materials were prepared without the use of any binder. The effect of grinding treatment on the characteristics of raw petroleum needle coke and on the properties of the sintered carbon compacts was investigated, and the sintering mechanism of the coke after grinding was discussed. Coke particle size and crystalline size decreased and the specific surface area of the coke increased with grinding, with obvious influence for up to 20 h grinding treatment. The interlayer spacing of the coke after graphitization at 2773 K was gradually increased and the a-axis constant was marginally reduced with the grinding time. Results from the sintering experiment show that carbon materials can be sintered from the ground coke and this ability was considered to result from the increase of surface energy, lattice distortion energy and fraction of volatile matters of the coke, which were induced by grinding treatment.
97103598 Expansion of delayed coker capacity Ou, S. Lianyou S’heji, 1997, 27, (I), 1-4. (In Chinese) Introduces the situation of I9 domestic operating delayed cokers. Potentialities of the main equipment of delayed cokers including the heaters, coking drums and fractionators were analysed. Measures for extending the processing capacity of the units such as lowering the recycle ratio, deeply distilling residue oil, reducing injection water amount into heater tubes and shortening coking cycle etc. were proposed.
97103599 Externally coking of coal
heated
retort
apparatus
suitable
for
Calderon, A. US 5,639,353 (Cl. 201-15; ClOB47/00), 17 Jun 1997, US Appl. 336,399, 9 Nov 1994, 5 pp. In this apparatus, the tubular retort is equipped with an elongated coking chamber with external heating and thermally conductive walls. It also has a charging mechanism for the feed of granular coal (or a similar material) into the chamber, removal of hot gas for collection, and the associated discharge of hot coke from the other chamber end into a quenching zone. The high-conductivity wall tiles are preferably manufactured from sintered SIC or SijNj-bonded SIC, and are installed in the coking zone of the otherwise thermally insulated retort. The hot gas from coking is collected and processed for cracking and pollution control.
97103600 Fundamental of bio-briquets
study on combustion
characteristics
Lu, G.-Q. et al. Kagoku Kogaku Ronbunshu, 1997, 23, (3), 404-412. (In Japanese) A study of pyrolysis and combustion characteristics of bio-briquettes were studied using an electrically heated batch combustor. The influences of biomass content of the bio-briquette on its combustion characteristics obtained by measuring the fuel consumption profile and the experimental
Fuel and Energy Abstracts
September
1997
303