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02762 Performance of ceramic fiber composite hot gas filters
13
iron-phosphate-based chemically phate ceramics for mixed waste stabilization
99102759
bonded phos-
Wagh, A. S. er al. WM’97 Proc., [computer optical disk], 1997, 1860-1866. A collaborative project to develop iron-phosphate based ceramics was initiated between Argonne National Laboratory and the V.G. Khlopin Ra Institute in St. Petersburg, Russia with the aim of developing chemical bonded phosphate ceramics for mixed waste stabilization. The starter powders are iron oxides, generated as cheap byproduct materials in the iron and steel industry. They contain a mixture of magnetite (Fes04) and hematite (FezOs). Both of these compounds were studied independently in the first stage of the project. Each was reacted with HaPOd solution to form iron phosphate ceramics. The reaction for magnetite was very rapid, and adding ash as the waste component containing hazardous contaminants formed a dense, hard ceramic, rich in glassy phase. The reaction of H3P04 solution with a mixture of hematite and ash waste contaminated with caesium and americum, however, proved too slow. Samples had to be molded under pressure, and were cured for 2-3 weeks before being hardened by heating at 350°F for 3 h. The resulting ceramics were tested for measurements of density, open porosity, compression strength, phase analyses using x-ray diffraction and DTA, and leaching tests using toxicity characteristic leaching procedure (TCLP) and ANS 16.1 with 7 days of leaching. With the preliminary information from these tests materials were evaluated for the stabilization of the Department of Energy’s mixed waste streams. 99102760
Latvian industrial wastes and glass ceramic on
thelr basis Rozenstrauha, I. er al. Law. Kim. Z., 1998, (2), 30-36. (In Latvian) An investigation of Latvian industrial wastes, comprising metallurgical slag, fly ash, etching refuse, coal, peat and oil shale ashes as well as glass wastes. The chemical and mineralogical composition of the wastes was determined. Amongst the findings were: compounds of iron, silicon, calcium, magnesium and zinc are the main chemical constituents of the waste. Metallurgical slag and fly ash contain small amounts of ecologically harmful elements, such as iron, cadmiun and tin. The main crystal phases of the studied wastes are; hematite, goethite, spine& sphalerite, siderite, calcite, anbydrite and corundum. Rapidly quenched melts from peat and oil shale ashes have a characteristic glassy structure. The mineralogical composition of materials is similar to the composition of natural rocks. Sintering and melting temperatures of wastes vary. The wastes wide range of sintering and melting temperatures give the possibility to produce glass ceramics by forming of glassy matrix. 99102761
Manufacture of ceramic foams by using waste
99lO2763
The separation efficiency and regeneration behavior of ceramic barrier filters at high temperatures determined by optical partfcle size and concentration measurement
Berbner, S. and Umhauer, H. High Temp. Gas Clean., [Pap. Inr. Symp. Exhib. Gas Clean. High Temp.], 3, 1996, 718-727. Edited by Schmidt, E., Institut fur Mechanische Verfahrenstechnik und Mechanik der Universitaet Karlsruhe, Karlsruhe, Germany. In order to characterize particle removal behaviour of cake-forming rigid ceramic barrier filters, the pressure drops, fractional efficiency and particle concentration increase on the clean gas side during a pulse jet cleaning event have to be determined. A measurement technique is needed that can record particle size and quantity directly within the given gas particle stream under prevailing conditions (in-situ measurement). The size of test dust particles was 0.1-10 pm. One of the few techniques that can be used is particle counting and sizing by scattered light measurement, as particle concentration measured in the clean gas flow behind the filter is very low. An optical particle counter was developed which uses an optically-defined measuring volume combined with signal control, which provides a free working distance of 200 mm. The optical access to dust transported in hot gas flow in 60-100 mm diameter pipes protects the instrument from heat. This device was used to examine separation and cleaning behaviour of cakebuilding ceramic barrier filter elements. Measurements at temperatures $lOOo”C were conducted with a quartz particle fraction as test dust. The paper discusses the fractional filtration efficiency and change of particle concentration on the clean gas side as a consequence of a pulse jet cleaning event, using parameters such as temperature, filtration time and conditioning of tested filter elements.
Synthesis of anorthite light refractory brick by using natural minerals
99102764
Ni, W. et al. Dizhi Zhaokuang Luncong, 1998, 13, (2), 1-9. (In Chinese) It is possible to manufacture anorthite light refractory bricks using natural minerals. In this study, experimental results suggest that coal gangues, kyanite, wollastonite, Suzhou clay and calcium aluminate cements make good anorthite light bricks with a foaming method. The raw materials have to be milled to a grain size smaller than 320 meshs and the optimum temperature of sintering is at 1300°C. The classification temperature of the resultant refractory brick is 1260°C its cold crushing strength is 1.15 MPa, its modulus of rupture is 0.92 MPa, its thermal conductivity at 800°C is 0.17 W/m.k and the linear change after a 1230°C x 24 h reheating is 0.128%.
13
materfals Horikawa, H. and Katsuyo, K. Jpn. Kokai Tokkyo Koho JP 10 297,977 [98 297, 9771, (Cl. C04B38/00), 10 Nov 1998, Appl. 97/139, 066, 22 Apr 1997, 8 pp. (In Japanese) To manufacture the title ceramic foams coal ash, magnesium compound powders with 25 wt% Magnesium oxide and powders with plasticity should be mixed to give a product with the following composition, MgO 3-10, Fez03 2-16, AlzOs 10-25 and SiOr 50-80 wt%. The resulting powder mixture should be granulated into particles with 0.1-10 mm diameter and fired at llOO-1300°C. The magnesium compound should either be pulp sludges, incineration ash of pulp sludges, and/or dust of peridotites. Dehydrated cake made from earth dug out of roads or cement can be used as the powders with plasticity. The resulting ceramic foams posses high strength at a low cost. Furthermore, efficient use of waste materials is achieved.
Space heating and cooling
SPACE HEATING AND COOLING
99102765
Carbon-dioxide emissions from an integrated small-scale CHP and absorption chiller system
Riley, J. M. and Probert, S. D. Applied Energy, 1998, 61, (4), 193-208. If the combined heat-and-power (CHP) unit’s heat-output is increased, so as to supply all the heat required by the absorption chiller, then the emissions from the integrated small-scale CHP and absorption chiller system are reduced by up to 0.06 kg of COz per kWh at design conditions or by up to 0.10 kg of CO2 emissions per kWh of cooling delivered for lower cooling water temperatures. These correspond to reductions of 22% and 40% respectively, when compared with those produced by a similarly sized electrically-driven vapour-compression chiller.
Computer simulation and experimental analysis of working fluids for absorption cycles
99102766 99102762
Performance of ceramic fiber composite hot gas
filters Fischer, E. M. and Smith, R. G. High Temp. Gas Clean., [Pap. Int. Symp. Exhib. Gas Clean. High Temp.] 3, 1996, 806-817. Edited by Schmidt, E., Institut fib Mechanische Verfahrenstechnik und Mechanik der Universitaet Karlsruhe, Karlsruhe, Germany. An overview of laboratory and demonstration testing of a novel rigid candle-type filter produced by 3M Company are presented. An advanced ceramic composite design combined specialized textile architecture with a chemical vapour deposition process to produce a lightweight, thin-walled, toughened composite hot gas filter. This filter consists of continuous ceramic fibres reinforcing a silicon carbide matrix. A commercial viable process to produce the filters was developed. The filter demonstrated good performance in a variety of application test environments focused on pressurized fluidized bed combustion, integrated gasification combined cycle and commercial incineration. Laboratory tests included oxidizing/ corrosive exposures, oxidizing exposures, mechanical testing and thin-wall filter mounting analysis. Test exposure conditions included temperatures 5950°C (1742°F) with alkali and water vapour in flowing air. Filter sizes ranged from small 2.5 cm laboratory mini-filters to full size 60 mm diameter x 1.5 m length candle filters. Operational demonstration conditions included atmospheric and pressurized systems and oxidizing and reducing atmospheres. Filter test results in North American and European demonstrations are reported. The advantage of graceful ceramic composite crack behaviour for applications mentioned and other issues identified during exposure and performance testing are discussed.
Riffat, S. B. and James, S. J. Insrirure ofEnergy, 1998, LXXI, (489) 158162. The working fluids, potassium formate-water and lithium bromide-water were compared for use in absorption cycles by computer simulation and experimental analysis. The absorption refrigeration cycles simulated include single-effect, double-effect and vapour recompression. A smallscale test rig was used to compare the absorption and desorption rates of the two working fluids. Due to the high pressure of potassium formatwater, a low absorber temperature (e.g. 25°C) is required for the absorption chiller to operate at low temperatures (e.g. 5°C). Potassium format-water solution could also be used in several applications, including desiccant cooling, drying, gas dehydration and water desalination, that are not restricted by operating conditions required in absorption chillers. 99102767
Determination
of energy loss characteristics
of
dampers
Gan, G. and Riffat, S. B. Inr. J. Energy Res., 1999, 23, (l), 61-69. The pressure loss coefficient of a flat-plate damper for ducted air systems was determined using computational fluid dynamics (CFD) and experimental measurement. The constant-injection tracer-gas technique and a pitot tube were used to measure mean air velocity in a square duct fitted with a damper. Pressure distribution along the duct was measured using static pressure tappings. The pressure loss coefficient was calculated from the measured pressure loss and mean velocity for the duct fitting. CFD was used to predict airflow and pressure distribution in the duct. The predicted pressure loss coefficient was generally agreed with experimental results.
Fuel end Energy Abstracts
July 1999
267
iron-phosphate-based chemically phate ceramics for mixed waste stabilization
99102759
bonded phos-
Wagh, A. S. er al. WM’97 Proc., [computer optical disk], 1997, 1860-1866. A collaborative project to develop iron-phosphate based ceramics was initiated between Argonne National Laboratory and the V.G. Khlopin Ra Institute in St. Petersburg, Russia with the aim of developing chemical bonded phosphate ceramics for mixed waste stabilization. The starter powders are iron oxides, generated as cheap byproduct materials in the iron and steel industry. They contain a mixture of magnetite (Fes04) and hematite (FezOs). Both of these compounds were studied independently in the first stage of the project. Each was reacted with HaPOd solution to form iron phosphate ceramics. The reaction for magnetite was very rapid, and adding ash as the waste component containing hazardous contaminants formed a dense, hard ceramic, rich in glassy phase. The reaction of H3P04 solution with a mixture of hematite and ash waste contaminated with caesium and americum, however, proved too slow. Samples had to be molded under pressure, and were cured for 2-3 weeks before being hardened by heating at 350°F for 3 h. The resulting ceramics were tested for measurements of density, open porosity, compression strength, phase analyses using x-ray diffraction and DTA, and leaching tests using toxicity characteristic leaching procedure (TCLP) and ANS 16.1 with 7 days of leaching. With the preliminary information from these tests materials were evaluated for the stabilization of the Department of Energy’s mixed waste streams. 99102760
Latvian industrial wastes and glass ceramic on
thelr basis Rozenstrauha, I. er al. Law. Kim. Z., 1998, (2), 30-36. (In Latvian) An investigation of Latvian industrial wastes, comprising metallurgical slag, fly ash, etching refuse, coal, peat and oil shale ashes as well as glass wastes. The chemical and mineralogical composition of the wastes was determined. Amongst the findings were: compounds of iron, silicon, calcium, magnesium and zinc are the main chemical constituents of the waste. Metallurgical slag and fly ash contain small amounts of ecologically harmful elements, such as iron, cadmiun and tin. The main crystal phases of the studied wastes are; hematite, goethite, spine& sphalerite, siderite, calcite, anbydrite and corundum. Rapidly quenched melts from peat and oil shale ashes have a characteristic glassy structure. The mineralogical composition of materials is similar to the composition of natural rocks. Sintering and melting temperatures of wastes vary. The wastes wide range of sintering and melting temperatures give the possibility to produce glass ceramics by forming of glassy matrix. 99102761
Manufacture of ceramic foams by using waste
99lO2763
The separation efficiency and regeneration behavior of ceramic barrier filters at high temperatures determined by optical partfcle size and concentration measurement
Berbner, S. and Umhauer, H. High Temp. Gas Clean., [Pap. Inr. Symp. Exhib. Gas Clean. High Temp.], 3, 1996, 718-727. Edited by Schmidt, E., Institut fur Mechanische Verfahrenstechnik und Mechanik der Universitaet Karlsruhe, Karlsruhe, Germany. In order to characterize particle removal behaviour of cake-forming rigid ceramic barrier filters, the pressure drops, fractional efficiency and particle concentration increase on the clean gas side during a pulse jet cleaning event have to be determined. A measurement technique is needed that can record particle size and quantity directly within the given gas particle stream under prevailing conditions (in-situ measurement). The size of test dust particles was 0.1-10 pm. One of the few techniques that can be used is particle counting and sizing by scattered light measurement, as particle concentration measured in the clean gas flow behind the filter is very low. An optical particle counter was developed which uses an optically-defined measuring volume combined with signal control, which provides a free working distance of 200 mm. The optical access to dust transported in hot gas flow in 60-100 mm diameter pipes protects the instrument from heat. This device was used to examine separation and cleaning behaviour of cakebuilding ceramic barrier filter elements. Measurements at temperatures $lOOo”C were conducted with a quartz particle fraction as test dust. The paper discusses the fractional filtration efficiency and change of particle concentration on the clean gas side as a consequence of a pulse jet cleaning event, using parameters such as temperature, filtration time and conditioning of tested filter elements.
Synthesis of anorthite light refractory brick by using natural minerals
99102764
Ni, W. et al. Dizhi Zhaokuang Luncong, 1998, 13, (2), 1-9. (In Chinese) It is possible to manufacture anorthite light refractory bricks using natural minerals. In this study, experimental results suggest that coal gangues, kyanite, wollastonite, Suzhou clay and calcium aluminate cements make good anorthite light bricks with a foaming method. The raw materials have to be milled to a grain size smaller than 320 meshs and the optimum temperature of sintering is at 1300°C. The classification temperature of the resultant refractory brick is 1260°C its cold crushing strength is 1.15 MPa, its modulus of rupture is 0.92 MPa, its thermal conductivity at 800°C is 0.17 W/m.k and the linear change after a 1230°C x 24 h reheating is 0.128%.
13
materfals Horikawa, H. and Katsuyo, K. Jpn. Kokai Tokkyo Koho JP 10 297,977 [98 297, 9771, (Cl. C04B38/00), 10 Nov 1998, Appl. 97/139, 066, 22 Apr 1997, 8 pp. (In Japanese) To manufacture the title ceramic foams coal ash, magnesium compound powders with 25 wt% Magnesium oxide and powders with plasticity should be mixed to give a product with the following composition, MgO 3-10, Fez03 2-16, AlzOs 10-25 and SiOr 50-80 wt%. The resulting powder mixture should be granulated into particles with 0.1-10 mm diameter and fired at llOO-1300°C. The magnesium compound should either be pulp sludges, incineration ash of pulp sludges, and/or dust of peridotites. Dehydrated cake made from earth dug out of roads or cement can be used as the powders with plasticity. The resulting ceramic foams posses high strength at a low cost. Furthermore, efficient use of waste materials is achieved.
Space heating and cooling
SPACE HEATING AND COOLING
99102765
Carbon-dioxide emissions from an integrated small-scale CHP and absorption chiller system
Riley, J. M. and Probert, S. D. Applied Energy, 1998, 61, (4), 193-208. If the combined heat-and-power (CHP) unit’s heat-output is increased, so as to supply all the heat required by the absorption chiller, then the emissions from the integrated small-scale CHP and absorption chiller system are reduced by up to 0.06 kg of COz per kWh at design conditions or by up to 0.10 kg of CO2 emissions per kWh of cooling delivered for lower cooling water temperatures. These correspond to reductions of 22% and 40% respectively, when compared with those produced by a similarly sized electrically-driven vapour-compression chiller.
Computer simulation and experimental analysis of working fluids for absorption cycles
99102766 99102762
Performance of ceramic fiber composite hot gas
filters Fischer, E. M. and Smith, R. G. High Temp. Gas Clean., [Pap. Int. Symp. Exhib. Gas Clean. High Temp.] 3, 1996, 806-817. Edited by Schmidt, E., Institut fib Mechanische Verfahrenstechnik und Mechanik der Universitaet Karlsruhe, Karlsruhe, Germany. An overview of laboratory and demonstration testing of a novel rigid candle-type filter produced by 3M Company are presented. An advanced ceramic composite design combined specialized textile architecture with a chemical vapour deposition process to produce a lightweight, thin-walled, toughened composite hot gas filter. This filter consists of continuous ceramic fibres reinforcing a silicon carbide matrix. A commercial viable process to produce the filters was developed. The filter demonstrated good performance in a variety of application test environments focused on pressurized fluidized bed combustion, integrated gasification combined cycle and commercial incineration. Laboratory tests included oxidizing/ corrosive exposures, oxidizing exposures, mechanical testing and thin-wall filter mounting analysis. Test exposure conditions included temperatures 5950°C (1742°F) with alkali and water vapour in flowing air. Filter sizes ranged from small 2.5 cm laboratory mini-filters to full size 60 mm diameter x 1.5 m length candle filters. Operational demonstration conditions included atmospheric and pressurized systems and oxidizing and reducing atmospheres. Filter test results in North American and European demonstrations are reported. The advantage of graceful ceramic composite crack behaviour for applications mentioned and other issues identified during exposure and performance testing are discussed.
Riffat, S. B. and James, S. J. Insrirure ofEnergy, 1998, LXXI, (489) 158162. The working fluids, potassium formate-water and lithium bromide-water were compared for use in absorption cycles by computer simulation and experimental analysis. The absorption refrigeration cycles simulated include single-effect, double-effect and vapour recompression. A smallscale test rig was used to compare the absorption and desorption rates of the two working fluids. Due to the high pressure of potassium formatwater, a low absorber temperature (e.g. 25°C) is required for the absorption chiller to operate at low temperatures (e.g. 5°C). Potassium format-water solution could also be used in several applications, including desiccant cooling, drying, gas dehydration and water desalination, that are not restricted by operating conditions required in absorption chillers. 99102767
Determination
of energy loss characteristics
of
dampers
Gan, G. and Riffat, S. B. Inr. J. Energy Res., 1999, 23, (l), 61-69. The pressure loss coefficient of a flat-plate damper for ducted air systems was determined using computational fluid dynamics (CFD) and experimental measurement. The constant-injection tracer-gas technique and a pitot tube were used to measure mean air velocity in a square duct fitted with a damper. Pressure distribution along the duct was measured using static pressure tappings. The pressure loss coefficient was calculated from the measured pressure loss and mean velocity for the duct fitting. CFD was used to predict airflow and pressure distribution in the duct. The predicted pressure loss coefficient was generally agreed with experimental results.
Fuel end Energy Abstracts
July 1999
267