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Yoshiaki TODA, Hideaki KUSHIMA, Kazuhiro KIMURA, Fujio ABE
Article type: Article
Session ID: 3627
Published: September 18, 2005
Released on J-STAGE: August 01, 2017
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Effects of the chemical compositions and the heat treatment on creep strength of a 15 Cr ferritic steel with ferrite matrix were investigated. The creep rupture lives of Fe-15Cr-1Mo-3W-0.2V-0.05Nb-0.003B (mass%) steel were extended longer than that of the conventional ferritic creep-resistant steel of ASME T92 by optimizing tungsten, cobalt, carbon and nitrogen content and increasing the cooling rate from annealing temperature. It was found that the precipitation strengthening effect of fine particles identified as intermetallic compounds and the thermal stability of them in ferrite matrix were effective in improvement in the creep strength of the steels. The precipitation-strengthened 15Cr ferritic steel is expected to possess superior oxidation resistance because of its high chromium content. It should be reasonable to conclude, therefore, that the developing steel is a promising materials for high-temperature structural component of the high-efficiency fossil-fired power plants in the future.
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Toshihiko YAMADA, Toshiro FUJIMORI, Takashi KIGA, Mutsuo KATO
Article type: Article
Session ID: 3628
Published: September 18, 2005
Released on J-STAGE: August 01, 2017
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Pulverized-coal combustion under oxygen and recycle flue gas (Oxy-fuel combustion) is expected to be one of the promising systems on CO_2 recovery from pulverized-coal fired power plant. The research and development on Oxy-fuel combustion technology had advanced under the Clean Coal Technology Program from 1992. It can be suggested through these studies that Qxy-fuel combustion system is the economical and high efficiency systems for CO_2 recovery from the pulverized-coal fired power plant. Feasible study is now advanced on the application of this technology to the actual existing power plant in Australia. In this paper, we introduce the results of previous study on the conceptual design of the boiler and the outline of current feasible study.
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Nobuyuki SUZUKI
Article type: Article
Session ID: 3629
Published: September 18, 2005
Released on J-STAGE: August 01, 2017
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The EAGLE pilot plant test of the coal processing amount 150tons a day has been executed as a joint research of EPDC (Electric Power Development Co., Ltd.) and NEDO (New Energy and Industrial Technology Development Organization) since fiscal year 1995. Coal gasification is a key technology of a super-high efficiency power generation system, such as IGCC (Integrated Coal Gasification Combined Cycle) or IGFC (Integrated Coal Gasification Fuel Cell Combined Cycle). In addition, the gas from gasifier is applicable in the hydrogen for the fuel cell, and raw material of the clean fuels such as DME (Di-methyl ether) and GTL (Gas to Liquid). This paper describes the development status of the EAGLE technology based on more than 3000 hours operation.
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Naomitsu HIRATSUKA, Jun WADA
Article type: Article
Session ID: 3630
Published: September 18, 2005
Released on J-STAGE: August 01, 2017
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In Japan coal is an important energy resource in terms of energy security, stability in price and supply. However, coal emits more greenhouse gas than other fossil fuels. IGCC is a promising clean coal technology to harmonize the reduction of greenhouse gas and coal utilization. Japan has been working on development of a unique air-blown IGCC technology that realizes the highest net efficiency and environmental friendliness. Clean Coal Power R&D Co., Ltd. and 9 utilities, EPDC and CRIEPI started the 250MW IGCC demonstration project in 2001. The demonstration project consists of three periods; plant design, construction, and test operation. Currently, the plant is under construction inside the Nakoso power station of Joban Joint Power Co., Ltd. in Iwaki City. Construction will be completed in August 2007, followed by a series of operation tests for 31 months. This paper presents the outline of the demonstration plant and the latest status of the project.
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Hiroaki WATANABE, Maromu OTAKA, Saburo HARA
Article type: Article
Session ID: 3631
Published: September 18, 2005
Released on J-STAGE: August 01, 2017
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High efficiency and a stable operation difficulty of an entrained flow coal gasifier originate in a discharge of slag. It is necessary to reduce air ratio to achieve high cold gas efficiency, even though a risk of a blockage of the slag outlet increases on the other hand. An optimization of a rational operating condition is necessary. The purpose of this study is to develop an evaluation and optimization technique for the operating the coal gasifier. This paper describes a methodology for the optimization of the operating conditions using relationship between operating conditions, gasification performance and molten slag behavior. 2 tons/day coal gaisifer was used to obtain gasification performance and molten slag behavior data. Gas-Particle and Gas-Liquid two phase numerical simulation were also carried out to clarify the detailed behavior of molten slag. As a result, gasification performance, such as calorific value of product gas and recycle char rate, and molten slag behavior changing operaging conditions (air ratio) were clarified. In addition, an operational evaluation index was obtained by the examination of the molten slag viscosity and the gasification performance.
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Yasuhisa NAKASO, Akihiko SUGIYAMA, Shinji ITOH
Article type: Article
Session ID: 3632
Published: September 18, 2005
Released on J-STAGE: August 01, 2017
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Development of technology for the energy saving is significant issue posted to prevention of global warming. Heat pump and thermal storage system has high potentiality for reduction greenhouse gases. In this paper, we suggest some notations for developing heat pump equipment, thermal storage system, control procedure, performance evaluation, energy utilization and peripheral systems from user side.
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Wataru SEKI, Kenji UEDA, Yoshinori SHIRAKATA, Kenichiro NISHII, Yasush ...
Article type: Article
Session ID: 3633
Published: September 18, 2005
Released on J-STAGE: August 01, 2017
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An application of optimized variable speed control for turbo chiller using inverter enables reduction in annual power consumption. Micro-turbo S series have attained high performance for about 80% or more than the conventional machines by means of improvement.
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Kousaku NISHIDA, Noriyuki ARATA, Shusaku JIN
Article type: Article
Session ID: 3634
Published: September 18, 2005
Released on J-STAGE: August 01, 2017
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In cold, snowy regions, a snow-melting system is important toward securing traffic safety. In recent years, snow-melting systems utilizing heat pump systems have been developed, because of low energy consumption and contribution to preserve of the environment. But in heavy snowfall area such as Hokkaido, electric heating cable systems and boiler systems are used because of lack of heat source for heat pump systems. In this study, we have developed a new snow-melting heat pump system utilizing CO_2 refrigerant, and we have designed heating pipe arrangement adjusting to the CO_2 heat pump system. This system can supply high temperature brine and high heat flux to the road surface. Results from a pilot plant in Hirosaki, obtained higher COP as compared with heat pump systems utilizing other refrigerants, and good snow-melting conditions.
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Takashi OKAZAKI
Article type: Article
Session ID: 3635
Published: September 18, 2005
Released on J-STAGE: August 01, 2017
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The experiments and calculations were carried out to evaluate the transient operation characteristics of a cooling system with natural circulation loop using CO_2. The characteristics of the reverse circulation observed under the supercritical state were analyzed from a point of the air intake temperature profile at the inlet of the heat exchangers. As a result, the air intake temperature profile causes the driving head difference for the reverse circulation. In addition, the driving head difference for the reverse circulation depends on the density change to the temperature under the supercritical state.
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Kenichi HIGUCHI, Hideyuki SUEHIRO, Takeshi UEDA
Article type: Article
Session ID: 3636
Published: September 18, 2005
Released on J-STAGE: August 01, 2017
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A Gas Heat Pump is an air-conditioner letting a compressor operate with gas engine, and shows high performance at heating operation by making good use of exhaust heat from engine. As the demand for alternative refrigerant increase for ozone layer protection, the new refrigerant R410A is expected to improve the driving efficiency by its superior heat condition. In comparison with a conventional refrigerant; however, the characteristics of the new refrigerant are greatly different and more effective design is needed. The refrigeration cycle simulation technology to predict air-conditioning performance becomes indispensable. Therefore, we built the accurate refrigerant cycle simulation of GHP corresponding to R410A refrigerant with modeling in two thermal components. The one is the heat effect to be mixed with circulating oil that prevent a compressor from being branded; the other is the heat exchanger which helps evaporation by exhaust heat from engine.
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Kenji YOSHIDA, Masaya MIYABE, Isao KATAOKA
Article type: Article
Session ID: 3637
Published: September 18, 2005
Released on J-STAGE: August 01, 2017
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Experimental studies on turbulence structure and characteristics on wavy interface on liquid film flow in annular two-phase flow were carried out concerned with the injector. In the central steam jet injector, steam/water annular two-phase flow is formed in the mixing nozzle, which consists of nozzle, throat and diffuser part. To make an appropriate design for high-performance steam injector system, it is important to accumulate the fundamental data of the thermo-hydrodynamic characteristics of annular flow passing through the steam injector. In this study, the gas-phase turbulence structure and characteristics of the wavy interface on liquid film flow were experimentally investigated. The measurements for gas-phase turbulence were precisely performed by using the hot-wire anemometer, and made clear the velocity profiles and turbulent intensity in the injector nozzle. The measurements for liquid film thickness by the electrode needle method were also carried out to investigate the characteristics of wavy interface such as base film thickness and wave height.
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Keisuke TAKESHITA, Akinori NAGASHIMA, Yoshiharu AMANO, Takumi HASHIZUM ...
Article type: Article
Session ID: 3638
Published: September 18, 2005
Released on J-STAGE: August 01, 2017
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This paper reports the effectiveness evaluation of a power and refrigeration hybrid cycle which is driven by a sensible heat source. The hybrid cycle employs ammonia-water mixture (AWM) as working fluid; in the configuration with which the ammonia absorption refrigerator and the AWM turbine cycle are connected by several pipelines. The authors carried out the simulation calculation, and investigate the performance of the hybrid system when the heat source flow rate ratio changes. In order to compare the consequences of the calculations, the exergy efficiency and the exergy availability are defined. The exergy efficiency or the exergy availability increase correspond the effect of hybridization. The increase of the exergy efficiency becomes maximum (5.1%) when the flow rate ratio is 0.25, and that of the exergy availability becomes maximum (2.9%) when the flow rate ratio is 0.75.
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Yuji KAWABATA, Shinji Takara, Jiro SENDA, Mamoru SENDA
Article type: Article
Session ID: 3639
Published: September 18, 2005
Released on J-STAGE: August 01, 2017
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From the viewpoint of effective use of energy, a Co-generation system (here after CGS) is considered as one of the significant strategies to achieve energy conservation. In recent year, CGS is introduced to low capacity and low heat to power ratio object such as household use and business place. However, Along with this, the total efficiency through the year become low because of low generating efficiency and low exhaust heat-using efficiency. So, it is necessary to find the problem by evaluating the influence of low capacity and low heat to power ratio on effective use of energy. In this study, we evaluate the effective use of energy using heat quantity and exergy for 200kW gas engine cogeneration system introducing to Energy Conversion Research Center in Doshisha University. As the result, we clear up the factor that influence on effective use of energy.
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Yoshiaki TANAKA, Naotake OHTSUKA, Yasunori SHINDO
Article type: Article
Session ID: 3640
Published: September 18, 2005
Released on J-STAGE: August 01, 2017
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Windmills are used for most of wind power plants. However, the plant generates unstable power due to variable wind velocity and has noise, view and bird striking problems. In order to solve these problems, a new wind power generator was proposed by applying resonant vibration of liquid in a U-tube. Water in the tube was oscillated by sending air by an air blower and sheltering the air periodically by rotating a semicircle plate. The influence of quantity of water and shape of the tube on resonant amplitude and attenuation of vibration of water was investigated to discuss the practical application of the concept.
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Article type: Appendix
Pages
App4-
Published: September 18, 2005
Released on J-STAGE: August 01, 2017
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