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Recycling of coal washing refuse for the fabrication of clay-based refractory ceramic bricks
13
Space heating and cooling
technology non-optimum regime for the Romelt process, the regime in which coal blocks the surface of the slag bath. The results of the studies were used to develop a technology for a Romelt unit with a capacity of 320000 tons of pig iron a year. 02/02198 Two-stage blowing of powdered coal into blast furnace for ironmaking Shen, F. el al. Faming Zhuanli Shenqing Gongkai Shuomingshu CN 1,300,858 (Cl. C2lBS~OO), 27 Jun 2001, Appl. 2,000,123,294, 23 Nov 2000. 5. (In Chinese) The process comprises blow injection of powdered coal with a carrier gas into the molten zone and the bosh area in addition to the conventional blow injection areas through tuyeres around the periphery of a blast furnace at different levels. Preferably, the carrier gas is an inert gas.
12
REFRACTORIES/ CERAMICS Properties,
production,
applications
02/02199 Glass with high transparency, their manufacture, and frits for their manufacture Sato, T. and Ama, N. Jpn. Kokai Tokkyo Koho JP 2001 322,829 (Cl. CO3Cl/O2), 20 Nov 2001, Appl. 2000/139,695, 12 May 2000. 4. (In Japanese) The frits are melt-solidified products of mixtures of borax 100, cerium oxide 4-45, and cokes 0.1-10 weight parts. Optionally, the frits may also contain 1.3-4.0 weight part Er oxide or 0.02-0.4 weight parts Se. Glass having high transparency is manufactured by addition of the above stated frits to base glass soda-lime glass in the forehearth. Thus manufactured glass is also claimed. Low-cost glass having high transparency is manufactured 02lO2200 Recycling of coal washing refuse for the fabrication of clay-based refractory ceramic bricks Sidrak, F. Pat. Specif. (Petty) (Aust.) AU 732,853 (Cl. C04B35/528), 3 May 2001, Appl. 2000159,505, 21 Sep 2000. 6. Coal washing refuse is recycled for producing ceramic bricks by mixing with an equal amount of clay. The mixture may then be stored, and is extruded by conventional means. After extrusion and cutting or shaping, the articles are dried in a dryer and fired in a kiln. The products so produced are indistinguishable from conventional products, except that their insulating properties are enhanced.
13
SPACE HEATING COOLING
AND
02/02201 Collector selection for solar ejector cooling system Huang, B. J. ef ccl. Solar Energy, 2001, 71, (4), 269-274. The performance of a solar ejector cooling system is simulated using three different collectors: a conventional flat plate collector, a high efficiency flat plate collector and a vacuum-tube collector. It is shown that with the proper selection of the generating temperature an optimum COP can be achieved. The solar ejector cooling system using the single-glazed solar collector with selective surface and an enhanced air insulating layer can be most economical when operated at the optimum generating temperature of the ejector cooling machine. In this case, the solar system cost is around I USD per watt of cooling capacity for air conditioning applications. 02/02202 Development of a microchannel evaporator model for a CO* air-conditioning system Kim, M. and Bullard, C. W. Energy, 2001, 26, (IO), 931-948. This paper presents the development and verification of a heat exchanger model for evaluating the thermal performance of an evaporator for a CO2 mobile air-conditioning system. The model has been developed, on the basis of the finite volume method, with emphasis placed on the air-side heat and mass transfer processes. The 284
Fuel and Energy Abstracts
July 2002
governing equations are derived from mass and energy balances using the newly developed air-side heat transfer and friction loss correlations for microchannel heat exchangers under both dry and wet conditions. The calculated air-side heat transfer and pressure drop data are in good agreement with measured data. However, the refrigerant-side pressure drop estimation for microchannel tubes usually underestimates the measured value. The simulation results and importance of selecting appropriate heat transfer and pressure drop correlations for the microchannel heat exchanger are addressed. OZO2203 Effect of refrigerant charge on the performance of air conditioning systems Goswami, D. Y. er al. Inrer. J. Energy Res., 2001, 25. (E), 741-750. An air conditioning system operates in an optimal condition if the system is fully charged with a specified amount of refrigerant. Poor field maintenance or refrigerant leakage causes low level of charge resulting in a lower thermal performance and higher operating cost. An experimental investigation was conducted to study the effect of low charge level of R-22 on the performance of a 3-ton residential air conditioning system. The experimental results show that if a system is undercharged to 90 per cent then the effect is small: a 3.5 per cent reduction in cooling capacity and a 2 per cent increase in the coefficient of performance (COP). However, the system performance suffers serious degradation if the level of charge drops below 80 per cent. An ice layer formed on the outer surface of the cooling coil impedes the heat transfer between the warm air and cold refrigerant vapour. An economic analysis shows that the cost of properly charging an undercharged system which is at an 85 per cent charge level, can pay for itself in savings in a short period of 3-4 months. Energy storage comparison of sorption systems 02/02204 for cooling and refrigeration Mugnier, D. and Goetz, V. Solar Energy, 2001, 71, (I), 47-55. A comparison between different sorption systems (binary mix only) such as absorption, adsorption and solid/gas reaction is presented with relation to their storage capacity for cooling. So as to be complete, phase change material (PCM) storage capacity has been added. The results are presented in kWh per kilogram of the total mass of the species involved in the cycle: the refrigerant fluid and the sorbent. In order to make a real condition comparison, two simple case studies have been made using temperatures that are compatible with a solar heat source. It appears that for negative temperatures, solid/gas reaction with ammonia has the best capacity. Storage with phase change material appears to be quite competitive even if a little less efficient. For positive temperatures, the best storage capacity is for water (working fluid) in absorption with NaOH as absorbent and in reaction with CaCIa, MgCla and NaaS as salt. 02lO2205 Field study using the ground as a heat sink for the condensing unit of an air conditioner in Thailand Khedari, J. er u/. Energy, 2001, 26, (8), 797-810. This paper reports on an investigation of the feasibility of using earth to absorb the heat normally rejected into the atmosphere by the condensing unit of a conventional air conditioner. To this end, a copper tube of about 67 m in length was buried at a depth of 1 m underground, where the temperature was constant at about 27°C year round. The copper coil of an air type condenser is about 22 m long. For the buried condenser, the R-22 refrigerant requirement was 5.8 kg as compared with 1.2 kg for the air condenser system. It was found that with this modified condensing unit, the coefficient of performance (COP) was much higher than that of a conventional one: it varied between 7.1 (daytime) and 8.1 (night-time), compared to 2.8 and 3.1, respectively. The ground temperature near the buried copper coil did not increase, thus demonstrating the ability of the soil to dissipate the absorbed heat into the ground. Consequently, there is a high potential for contributing to environmental protection by using the ground as a heat sink. The elimination of the condensing fan is an additional advantage of the buried condenser system. 02lO2206 Heating and cooling energy recovery for an HVAC system: Economic analysis for the Italian climate Palombo, A. fnr. J. Energy Res., 2001, 25, (8) 675-688. In this paper the economic analysis of the energy recovery in alloutdoor-air HVAC systems for the Italian climate is performed. The energy recovery device considered here is the same for both heating and cooling periods. During the summer season, the energy saving is achieved by evaporative cooling. The performances of the hybrid innovative HVAC system and the traditional system are calculated hour by hour by following the test reference year (TRY) profile. Such analysis is carried out taking into account simultaneously, the trend of some climatic indexes computed in order to (i) better understand the influence of climate on the HVAC system behaviour, (ii) obtain a swift feasibility analysis of the energy recovery system and (iii) perform a rough operating cost estimate of the traditional HVAC system.
Space heating and cooling
technology non-optimum regime for the Romelt process, the regime in which coal blocks the surface of the slag bath. The results of the studies were used to develop a technology for a Romelt unit with a capacity of 320000 tons of pig iron a year. 02/02198 Two-stage blowing of powdered coal into blast furnace for ironmaking Shen, F. el al. Faming Zhuanli Shenqing Gongkai Shuomingshu CN 1,300,858 (Cl. C2lBS~OO), 27 Jun 2001, Appl. 2,000,123,294, 23 Nov 2000. 5. (In Chinese) The process comprises blow injection of powdered coal with a carrier gas into the molten zone and the bosh area in addition to the conventional blow injection areas through tuyeres around the periphery of a blast furnace at different levels. Preferably, the carrier gas is an inert gas.
12
REFRACTORIES/ CERAMICS Properties,
production,
applications
02/02199 Glass with high transparency, their manufacture, and frits for their manufacture Sato, T. and Ama, N. Jpn. Kokai Tokkyo Koho JP 2001 322,829 (Cl. CO3Cl/O2), 20 Nov 2001, Appl. 2000/139,695, 12 May 2000. 4. (In Japanese) The frits are melt-solidified products of mixtures of borax 100, cerium oxide 4-45, and cokes 0.1-10 weight parts. Optionally, the frits may also contain 1.3-4.0 weight part Er oxide or 0.02-0.4 weight parts Se. Glass having high transparency is manufactured by addition of the above stated frits to base glass soda-lime glass in the forehearth. Thus manufactured glass is also claimed. Low-cost glass having high transparency is manufactured 02lO2200 Recycling of coal washing refuse for the fabrication of clay-based refractory ceramic bricks Sidrak, F. Pat. Specif. (Petty) (Aust.) AU 732,853 (Cl. C04B35/528), 3 May 2001, Appl. 2000159,505, 21 Sep 2000. 6. Coal washing refuse is recycled for producing ceramic bricks by mixing with an equal amount of clay. The mixture may then be stored, and is extruded by conventional means. After extrusion and cutting or shaping, the articles are dried in a dryer and fired in a kiln. The products so produced are indistinguishable from conventional products, except that their insulating properties are enhanced.
13
SPACE HEATING COOLING
AND
02/02201 Collector selection for solar ejector cooling system Huang, B. J. ef ccl. Solar Energy, 2001, 71, (4), 269-274. The performance of a solar ejector cooling system is simulated using three different collectors: a conventional flat plate collector, a high efficiency flat plate collector and a vacuum-tube collector. It is shown that with the proper selection of the generating temperature an optimum COP can be achieved. The solar ejector cooling system using the single-glazed solar collector with selective surface and an enhanced air insulating layer can be most economical when operated at the optimum generating temperature of the ejector cooling machine. In this case, the solar system cost is around I USD per watt of cooling capacity for air conditioning applications. 02/02202 Development of a microchannel evaporator model for a CO* air-conditioning system Kim, M. and Bullard, C. W. Energy, 2001, 26, (IO), 931-948. This paper presents the development and verification of a heat exchanger model for evaluating the thermal performance of an evaporator for a CO2 mobile air-conditioning system. The model has been developed, on the basis of the finite volume method, with emphasis placed on the air-side heat and mass transfer processes. The 284
Fuel and Energy Abstracts
July 2002
governing equations are derived from mass and energy balances using the newly developed air-side heat transfer and friction loss correlations for microchannel heat exchangers under both dry and wet conditions. The calculated air-side heat transfer and pressure drop data are in good agreement with measured data. However, the refrigerant-side pressure drop estimation for microchannel tubes usually underestimates the measured value. The simulation results and importance of selecting appropriate heat transfer and pressure drop correlations for the microchannel heat exchanger are addressed. OZO2203 Effect of refrigerant charge on the performance of air conditioning systems Goswami, D. Y. er al. Inrer. J. Energy Res., 2001, 25. (E), 741-750. An air conditioning system operates in an optimal condition if the system is fully charged with a specified amount of refrigerant. Poor field maintenance or refrigerant leakage causes low level of charge resulting in a lower thermal performance and higher operating cost. An experimental investigation was conducted to study the effect of low charge level of R-22 on the performance of a 3-ton residential air conditioning system. The experimental results show that if a system is undercharged to 90 per cent then the effect is small: a 3.5 per cent reduction in cooling capacity and a 2 per cent increase in the coefficient of performance (COP). However, the system performance suffers serious degradation if the level of charge drops below 80 per cent. An ice layer formed on the outer surface of the cooling coil impedes the heat transfer between the warm air and cold refrigerant vapour. An economic analysis shows that the cost of properly charging an undercharged system which is at an 85 per cent charge level, can pay for itself in savings in a short period of 3-4 months. Energy storage comparison of sorption systems 02/02204 for cooling and refrigeration Mugnier, D. and Goetz, V. Solar Energy, 2001, 71, (I), 47-55. A comparison between different sorption systems (binary mix only) such as absorption, adsorption and solid/gas reaction is presented with relation to their storage capacity for cooling. So as to be complete, phase change material (PCM) storage capacity has been added. The results are presented in kWh per kilogram of the total mass of the species involved in the cycle: the refrigerant fluid and the sorbent. In order to make a real condition comparison, two simple case studies have been made using temperatures that are compatible with a solar heat source. It appears that for negative temperatures, solid/gas reaction with ammonia has the best capacity. Storage with phase change material appears to be quite competitive even if a little less efficient. For positive temperatures, the best storage capacity is for water (working fluid) in absorption with NaOH as absorbent and in reaction with CaCIa, MgCla and NaaS as salt. 02lO2205 Field study using the ground as a heat sink for the condensing unit of an air conditioner in Thailand Khedari, J. er u/. Energy, 2001, 26, (8), 797-810. This paper reports on an investigation of the feasibility of using earth to absorb the heat normally rejected into the atmosphere by the condensing unit of a conventional air conditioner. To this end, a copper tube of about 67 m in length was buried at a depth of 1 m underground, where the temperature was constant at about 27°C year round. The copper coil of an air type condenser is about 22 m long. For the buried condenser, the R-22 refrigerant requirement was 5.8 kg as compared with 1.2 kg for the air condenser system. It was found that with this modified condensing unit, the coefficient of performance (COP) was much higher than that of a conventional one: it varied between 7.1 (daytime) and 8.1 (night-time), compared to 2.8 and 3.1, respectively. The ground temperature near the buried copper coil did not increase, thus demonstrating the ability of the soil to dissipate the absorbed heat into the ground. Consequently, there is a high potential for contributing to environmental protection by using the ground as a heat sink. The elimination of the condensing fan is an additional advantage of the buried condenser system. 02lO2206 Heating and cooling energy recovery for an HVAC system: Economic analysis for the Italian climate Palombo, A. fnr. J. Energy Res., 2001, 25, (8) 675-688. In this paper the economic analysis of the energy recovery in alloutdoor-air HVAC systems for the Italian climate is performed. The energy recovery device considered here is the same for both heating and cooling periods. During the summer season, the energy saving is achieved by evaporative cooling. The performances of the hybrid innovative HVAC system and the traditional system are calculated hour by hour by following the test reference year (TRY) profile. Such analysis is carried out taking into account simultaneously, the trend of some climatic indexes computed in order to (i) better understand the influence of climate on the HVAC system behaviour, (ii) obtain a swift feasibility analysis of the energy recovery system and (iii) perform a rough operating cost estimate of the traditional HVAC system.