In order to rationalize the maintenance of batteries, we began the development activity of the equipment to evaluate the deterioration of batteries. The developed equipment can measure the battery characteristic with relation to residual capacity. We call this battery characteristic Vmd. The equipment has so useful advantages that users of the battery system can measure Vmd of all individual cells on operating condition of the battery. Here, we introduce considering of the development, qualification of the equipment to apply to the operating battery in our site, and the rationalization of the maintenance criteria of the battery.

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The Kansai Electric Power Co., Inc.(Kansai Denryoku) and Sumitomo Electric Industries, Ltd. began a joint research project on Redoxflow flow batteries in 1985. At the start of the research, mini cells with an electrode area of 9(cm)^2 were developed in order to select appropriate battery materials. As progress was made in the research, the battery scale has been successively enlarged, and the project has now reached the stage of practical application with Redoxflow battery systems as large as several hundred kW, and even several MW, being delivered to universities and factories. This paper describes the principle and features of Redoxflow batteries, reports the scope of applicability and gives examples of practical applications of Redoxflow batteries.

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The grinding capacity test results of a model DTM350/700 ball mill was investigated. It has been found that the ball mill current at the condition of its maximum coal dust output isn't just the maximum current probably, and so current change has significance for judging the ball mill's blockage situation. This paper offers the theoretical analysis on the relationship between the coal storage capacity in the ball mill and coal dust output, and on the relationship between the coal storage capacity and the mill's power consumption. These analytic and calculated results not only are accordant with the actual trend of ball mill current change, but also can estimate the ball mill's optimal coal storage capacity under the conditions of different ball loading. The relevant findings can provide the theoretical guide for design and operation management personnel of ball mill.

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Feasibility of a novel environment symbiotic micro cogeneration system for residential purpose has been investigated for Sustainable Marine City that we call SuMaC. SuMaC is a fictitious reclaimed island (800-900 ha) on Osaka bay coastal zone with 39,000 residents. Thermodynamic analysis was carried out for the micro cogeneration systems consisting of a micro gas turbine, a micro gas engine and a polymer electrolyte fuel cell as topping and a single effect absorption chiller as a bottoming, in which natural energies are highly utilized. And their performances and efficiencies were predicted quantitatively. Total efficiency of the system exceeds 80% when the micro gas turbine or micro gas engine was used as a prime mover. And feasibility of the proposed environment symbiotic micro cogeneration system was verified by computer simulation.

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Simplified double grade simulation model which gives electric and thermal energy balances in a renewable electric and thermal hybrid power system by only two days (the representative clear and cloudy days) calculations and clear day ratio in the period was proposed. The renewable energy power system consists of photovoltaic-thermal hybrid solar panels and a heat pump using underground water as a heat source. The errors in various simplified models were estimated in comparison with the results of full time integration every one minute. Analysis of annual electric and thermal energy balances and amount of carbon dioxide emissions for domestic size renewable electric and thermal hybrid power systems were demonstrated using the proposed simplified simulation model. The annual running cost and carbon dioxide emission in the renewable energy power system were extremely lower (1/2 and 1/10 rectively) than those in the conventional power system. Annual system running cost strongly depends on the coefficient of heat loss of the house and the solar panel area. Improvements of the thermal gain from the hybrid solar panel in cold climate regions were achieved with the low temperature heat storage tank added in the system and with optimization of the panel connections.

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Because of the metallic glasses amorphism, they can absorb much more hydrogen than crystalic solids creating metals hydrides. So, they present hydrogen accumulators as energy carrier. Their capacity as hydrogen accumulators depends particularly on their "amorphism". Thermal stability range of metallic glasses determination is very important then. Purpose of this work was to determine the temperature range of the amorphous state stability and the effect of carbon admixture, in the presence of hydrogen on amorphous stabilization. On the basis of experimental data proved that the glass tested is thermally stable until the temperature of 600K is reached. The degrees of amorphism and crystallization as well as the size of crystallites of metastable phases were determined using the thermostimulated exoelectron emission (TSEE) and X-ray diffraction techniques. Thermal stability range of metallic glasses plays significant role in using them for storage, transport and hydrogen usage for energy industry needs (fuel cells).

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A hybrid solar panel which consists of photovoltaic (PV) panels and a laminated heat collector has been commercialized in Japan. It is necessary to improve the collector efficiency, i. e., to reduce heat loss in order to realize hybrid solar panel applications in cold climate regions. The experiments were conducted with commercial scale panel modules mainly under a solar simulator. The result suggested that natural convection in the heat insulating space was the dominant heat loss process from the cover glass. The heat insulation gap was divided into many small cells with grids such as honeycomb and partition plate to prevent natural convection. The natural convection was well prevented, as a result, the heat loss from cover glass was reduced with installation of the grid in the heat insulation space. There was no dependence of the incident angle upon the collector efficiency of the panel module with the cells in spite of effective area decrease with shadow.

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A concept of SEAGUL system (Snow Enhancing Atomic-power Generation UtiLity) is proposed in this paper. Lowering the temperature of sea water for cooling of atomic-power plant will make a efficiency of power generation better and bring several ten MW additional electric power for 1356 MW class plant. The system concept stands an idea to use huge amount of seasonal storage snow for cooling water temperature control. In a case study for the Kashiwazaki-Kariwa Nuclear Power Station, it is estimated to coll down the sea water of 29℃ to 20℃ by 80 kt snow for 3 hours in a day would brought 60MWh electric power per a day. Annually 38.4Mt of stored snow will bring 1800 MWh electric power.

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This paper introduces a heat pump system with a latent heat storage utilization seawater installed in an aquarium. For heating purpose such as air conditioning in order to maintain the indoor conditions at constant temperature and constant relative humidity, and cooling water supply to the fish tank in the aquarium, heat from seawater is collected as the heat source for the heat pump system. With regard to the heat pump system using low-temperature unutilized heat source, development is introduced on a heat source load responsive heat pump system, with combines a load variation responsive heat pump utilizing seawater with a latent heat (ice plus water slurry) storage system using nighttime electric power serving for electric power load leveling. The objective of this study is to compare the actual operating characteristics and efficiency of a seawater-source heat pump with ice storage system to the predicted evaluation of the two assumed conventional system. The experimental COP (Coefficient of performance) of the proposed heat exchanger from seawater and latent heat storage cooling assisted heat pump system will be shown in detail.

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A pebble bed gasifier is composed of entrained flow section and packed bed section of ceramic balls (pebble bed section), and it has three main features : high efficiency of slag capturing; assurance of long reaction time; and thermal buffer function of the pebble bed. High temperature air is used as an oxidant to obtain high enough temperature inside of the gasifier to melt ash and realize tar free gasification. Two kinds of biomass samples were used as fuels in the gasification experiments. These were dried wood chips and carbonized fowl droppings, corresponding to high and low volatile matter fuel, respectively. It was shown that the carbon conversion rates were 96% and 80%, the cold gas efficiencies were 62% and 53% and the HHVs were 5.49MJ/m^3N and 3.50MJ/m^3N for each biomass sample, respectively.

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The present paper reports the experimental and modeling studies of a 4-cylinder, 4-stroke, direct injection diesel engine. Study is carried out for two modes of operations-one with straight diesel fueling and another in dual-fuel mode using natural gas and biogas of two compositions with a fixed amount o pilot diesel injection for the ignition of the charge. Both experiments and simulations are carried out for different engine speeds at different loading conditions. The results obtained from the simulations are in reasonable agreement with the experimental results; however, neglect of detailed combustion in the model resulted in higher rated power estimate of the engine. Lower cylinder gas pressure and higher bulk gas temperatures are obtained in case of fueling by natural gas, and these quantities decrease with increase in the carbon dioxide content of biogas.

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This paper presents the technologic characteristics and economics of 4MWe biomass integrated gasification (gas engine/steam turbine) combined cycles (BIG/CC) demonstration power plant, which is being under construction in China. It features a biomass fuel pretreating and feeding unit, a 1.5MWth CFB biomass gasifier, a gas cleanup unit, an internal combustion gas engine (ICGE) cycle producing 2.5MW electricity and a steam turbine cycle producing 1.5MW electricity. Comparing with the ICGEs single cycle systems, this technology route not only increases the overall energy efficiency of the power plant but also reduces the technological risks. A detailed cost model is developed for the present technology. Estimated cost of electricity suggests that 8MWe scale BIG/CC power plant can obtain good scale economy in China.

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As a biomass utilization technology, methanol or liquid fuel synthesis system applying proprietary gasifier and catalyst synthesis technology has been developed. In a test equipment operation, methanol was successfully derived and influence of gasification condition on conversion efficiency was verified. Demonstration plant project was started in 2001 as an R&D national project. This makes it possible to use renewable energy in the mobile and transportation fields.

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Experiments of the "semi-carbonization" that was the new type of pyrolysis at moderate temperature were conducted for cellulose : the main component of woody biomass, citric acid and their mixtures in order to clarify the optimal pyrolysis condition and the effect of acid additives on the semi-carbonization. The acid additive promoted dehydration of woody biomass, and affected the weight yield of char within the temperature region of the semi-carbonization. The analytical model to evaluate the energy value of the semi-carbonized fuel was presented based on the reduction in the value due to the transportation. The optimal pyrolysis condition of the semi-carbonized fuel was clarified for the dimensionless distance of the transportation. It was found that the acid additives contributed to saving the energy consumption of the "semi-carbonization" pyrolysis process and improving the transportation.

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A hybrid gas bearing with water evaporation from ultra-fine porous medium is newly proposed. The proposed bearing is considered to be applied to microturbines and have mainly three advantages suitable for the applications. The first is the stability improved by water evaporation from ultra-fine porous medium. The second is the effective lubrication by liquid water at start and stop of the journal rotation. The third is the cooling effect on the high-temperature journal due to water evaporation. Fundamental characteristics of the proposed bearing are clarified on the basis of a numerical simulation for water vapor, and compared with the conventional bearings the improved performance is demonstrated. Also, transition from water to vapor lubrication is analyzed taking the two-phase properties into account. A preliminary experiment is conducted, and stable start of the journal rotation is confirmed.

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Application of Sonic Soot Cleaning is increasing prevalence in power plant, but the development of Sonic Soot Cleaning is restrained as its technology does not fully indicated. In this paper, the general mathematic model of sound multiple scattering is established and calculated by using Addition theorem method, the effect of physical property of cylindrical tubes on sonic soot cleaning is investigated, the optimal frequency of Sonic Soot Cleaning is discussed, the conclusion drown by accurately calculating and synthetically analyzing, to the development and application of Sonic Soot Cleaning Tech, is significative.

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Aiming at the centrifugal fan which is widely used in power plants, in this paper using the strong nonlinear approaching capacity of RBFNN model and good generalizing ability of mathematic model, a monitoring model of fan performance based on hybrid NN is presented, which combines RBFNN model and partial least squares (PLS) model. The performance curves of 4-73No.8D are approached by experimental data and study results show that the model has higher precision than normal RBFNN model. In the last part of the paper, the application of the model under different conditions in studied.

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Small and medium size gas turbines are widely used for distributed power and combined heat and power. However, most have power generation efficiency of less than 35% because of the simple cycle. A chemically recuperated gas turbine (CRGT) has an advanced cycle, which recovers exhaust heat by endothermic reaction converting fuel into hydrogen-rich gas. Several papers report that the results of feasibility studies indicate CRGT would be effective for improving power generation efficiency of the simple cycle GT. Also, the CRGT using methanol steam reforming has been demonstrated, but the components and system operation have not been assessed technically in the case of natural gas. In order to realize the CRGT with natural gas steam reforming, we applied the CR system to a commercial 4MW simple cycle GT and examined the static mass and heat balance by process simulator. We designed a reformer consisting of tube bundles by numerical analysis, which considered mass and heat transfer and chemical reaction in the catalyst bed and clarified the master plan figure of the heat recovery system. Also, the reformer was structurally analyzed using FEM and the stresses due to internal pressure, gravity and temperature distribution were calculated and the stresses in the cross section under severe condition were evaluated with ASME code. This paper presents the results and discussions of these studies.

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The paper specifies principle of selection for condensate polish system (hereinafter referred to as CPS), based on characteristics of condensate quality, in conformity with concrete conditions of Huozhou Power Plant Second Phase Project. Power resin precoat filter is finally recommended as CPS for the project after comprehensive technical and economical comparison between individual ion exchanger and powder resin precoat filter.

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Because last stage blade is operated under wet steam condition, it is difficulty to measure the efficiency of auxiliary steam turbine. The measurement method of efficiency for auxiliary steam turbine driven feed pump is presented in this paper. This method is based on thermodynamic method and shaft power of auxiliary steam turbine, then the efficiency of auxiliary steam turbine is obtained. Firstly, the measurement theory and method of efficiency test are introduced, then the formulas of efficiency for auxiliary steam turbine driven feed pump are provided, at last, some auxiliary feed pumps of 300MW and 600MW steam turbine have been test. Measurement data shows the method can get good measurement data for efficiency of auxiliary steam turbine and it is suitable for engineering application.

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On the general heat exchanger of a vertical circular tube, cooling water is run from the bottom to the top in the tube. However, according to the last research of the dropwise condensation of authors, it is anticipated that the good heat transfer characteristic is obtained when the cooling water is run from the top to the bottom. Heat transfer characteristic on a vertical condensing circular tube was obtained by using a copper tube (o.d.40mm, i.d. 30mm and length 700mm). When the cooling water in the tube flew down and up, the heat transfer had a good characteristic in the case of water flowing down. And we evaluated the relation between the behavior of condensate drops and the heat transfer, and then, the sweeping action had a significant effect in this experimental conditions.

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The condensation heat transfer characteristic curves for a ternary vapor mixture of water, ethanol and air (or nitrogen) under several ethanol concentrations and relatively low concentrations of air (or nitrogen) were measured. The effect of non-condensable gas on several different domains in the condensation curves was discussed. The effect of non-condensable gas in the domains controlled by the diffusion resistance and the filmwise condensation was not notable; whereas that in the domain dominated by the condensate resistance of dropwise mode was remarkable. Moreover, variations due to changes in non-condensable gas concentration of several characteristic points representing the curves were discussed.

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Condenser fault diagnosis model is improved in the paper by using the method of fuzzy math and the technology of ANN. Typically fault-sign sample of condenser is redefined in the paper. The change of condenser parameters is not always caused by fault. It may be caused by the variety of unit load and environmental factors. So it is necessary to eliminate objective factors in fault diagnosis. The paper reestablished membership functions of running parameters that are changed according to unit load and environmental factors. New training arithmetic is used to shorten the time of diagnosing condenser fault. The structure of condenser fault diagnosis system is provided. The result, which is got by using the system, is consistent with the one that is deduced by using operating data and experiences.

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The most part of energy losses in fuel cells is due to the heat released by the exhaust gas to atmosphere. The exhaust gas consists of air and steam with sensible and latent heat. As a lot of latent heat is included in the mixture gas, its recovery is very important to improve the power system efficiency using the fuel cell. The thermal hydraulic behavior was experimentally studied in a compact heat exchanger for the latent heat recovery from air-steam mixture gas. The compact heat exchanger consisted of staggered banks of 10 (9) rows and 40 stages of bare tubes of small diameter. The parametric study varying the air mass concentration was conducted. The temperature distributions of cooling water and mixture gas and the amount of condensate were measured. Based on the previous basic studies, a thermal hydraulic prediction method was also proposed. For the condensation of steam on heat transfer tubes, the modified Sherwood number taking account of the mass absorption effect on the wall was used. The experimental results agreed well with the prediction proposed in this study.

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To investigate the momentum and heat transfer analogy for flow boiling, heat transfer coefficient and pressure drop of water flowing in a round tube with an internal diameter of 8.03 mm were simultaneously measured. A correlation of frictional pressure loss was obtained from the experimental data by modifying the correlation of Chisholm-Laird as Φ_l^2=1+17/X_<tt>+5/X_<tt>^2. From the comparison of the data of heat transfer coefficient, h_<TP>/h_<Lf>/(1-α), with correlations of the frictional pressure loss, Φ_l^2,it was found that the analogy between heat transfer and fluid friction did not hold for the flow boiling. The difference between them was considerably large and represented by an experimental factor of K ranging from 1.5 to 2.2. A turbulent eddy diffusivity model was applied to the forced convective evaporation heat transfer to an annular liquid film flow. The calculated results agreed well with the experimental data when the eddy diffusivity of heat, ε_H, proposed by Mudawwar and El-Masri for the freely falling turbulent liquid films with evaporation, was applied.

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In this paper two kind of rotating stall of blade row is tested on a 4-73No8D centrifugal fan in lab. In order to extract feature of rotating stall of 4-73 fan series, orthogonal harmonic wavelet and the reformed non-orthogonal HW, the delay rate of which in time domain is improved by author, are introduced to analyze time-frequency characteristic of different stall. The time-frequency feature of two kind of stall is obtained and the effectiveness and advantage of harmonic wavelet applying to analyze the unstable flow of centrifugal fans is proved.

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Karita Power Station New Unit 1,which started commercial operation on July 3,2001,has adopted the new power generation system PFBC, Pressurized Fluidized Bed Combustion, a combined cycle generation system. The system boasts high thermal efficiency, excellent environmental characteristics and compact size. Output from the steam turbine generator and gas turbine generator is 290MW and 75MW, respectively, with total output adjusted to 360MW, making the unit the largest PFBC plant in the world. In October 2002,combustion tests were conducted using an anthracite coal from Yangquan; and in April 2003,a world record was achieved for continuous operation hours of a PFBC plant. This paper focuses on the outline and operation status of Karita New Unit 1.

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The concept of "mass unit" for the thermal system of a coal-fired power generating unit is set up. Base on which, a new method for thermal system analysis and calculation is derived under energy balance theory and matrix theory. With this method, the structure and thermal character of the thermal system can be completely expressed with math language, and the thermal system calculation can be simplified effectively and be more precise and scientific.

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In this research, in order to verify the application of compound cycle to the ship power plant from the viewpoint of the effective use of energy, the performance analysis of a compound cycle and a Kalina cycle in which a mixture of ammonia water is used as the working fluid is achieved. Now, Kalina cycle is applied to the generating electricity plant on board ship. In analyzing Kalina cycle, it is very important to find the property values of a mixture of ammonia water precisely corresponding to ammonia concentration. The ammonia concentration was given by using the general-purpose computer program "PROPATH" for property value ranging from 0 to 100%. The exergy evaluation based on the second law of thermodynamics is done for this research.

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Japan's original "Air-blown IGCC" development, one of the most important national projects, has stepped up to enter in the final phase - demonstration. A 250MW plant is being constructed for demonstration. In order to conduct the project, a new company "Clean Coal Power R&D Co., Ltd. (CCP)" has been established on June 15th, 2001 by the nine regional utility companies of Japan, Electric Power Development Company (EPDC) and Central Research Institute of Electric Power Industry (CRIEPI)(hereafter called as '11 corporations'). Plant construction will start in 2004 followed by operation tests through 2009. This paper presents the latest status of the project and outline of the demonstration plant.

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In this paper, the current situation of China electricity power industry was introduced. The properties, existing level and development trend of IGCC were analyzed. The relative research and development of the state project "Study on technical feasibility for the demonstration project of IGCC generation" of "8th five years (1991-1995) plan" and the state project "Study on IGCC key technologies" of "9th five years (1996-2000) plan" in China were reviewed. The research contents and targets of the state project "The integrated design and the dynamical properties for IGCC power plant" of "10th five years (2001-2005) plan" in China were described. The status of IGCC demonstration project in China and the preferential policy of Chinese government on IGCC demonstration project were introduced. The function and prospect of IGCC in sustainable development of electric power in China were also analyzed predicted.

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It is clear that the IGFC system, which is composed of a fuel cell, gas turbine and steam turbine, the so-called triple combined cycle power generation system, has considerably higher efficiency when compared with a conventional coal-fired power plant according to this feasibility study. The EAGLE pilot plant operation has been conducted to develop a gasifier and establish a gas clean-up system for cells since July 2001.

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The conversion of primary energy from natural sources and the subsequent utilisation of secondary forms of energy are basically related to the development of our society with its continuous change of requirements which are predominantly due to an increase in population and prosperity as well as the broadening of the needs in our modern life. Consequently the consumption of primary energy resources rose drastically during the last 5 decades. However, the increasing awareness of environment pollution from the use of e.g. fossil fuels, the limitation of the availability of such sources as well as market considerations and costs forces governments to re-orientate their energy policy in order to ensure a sustainable supply for the future of their societies. The paper will start with an overview of the energy market development in general and by comparing certain key areas in relation to their boundary conditions. In particular, the situation in Europe will be discussed and the consequences for political actions and technological needs for the future energy supply will be highlighted.

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The GTHTR300 aiming at electric generation with its thermal efficiency of 46% is a safe and economically competitive HTGR in 2010s. A helium gas turbine system connected with the reactor is designed based on existing technologies developed for fossil gas turbine systems. However, there are some uncertainties in performance of a helium gas compressor, electric magnetic bearings and control system. In order to confirm these technical uncertainties, a 1/3 scale model of the compressor and 1/3 scale magnetic gearings will be manufactured and tested in the simulated condition of the GTHTR300. Also, a 5 MW helium gas loop composed of the gas turbine system and electric heaters will be constructed, and control performance during startup and shutdown, and off-normal transients such as loss of site loads will be tested to streamline the gas turbine system. This paper describes R&D plans focusing on the 1/3 scale compressor model test as well as unique design features of the GTHTR300.

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Compared with traditional thought in thermal economic analysis, the inverse thought (i.e., "merged first, and analyzed later") is proposed. Based on which, combined with the equivalent heat drop method and q-γ-τ matrix form, the paper constructs the power-efficiency distributed matrix equation (PEDME) and does the preliminary studies of the thermodynamic system analysis based on this matrix equation. Its matrix structure is well correlated with the thermodynamic system, and there is element represented the thermal economy in the matrix equation, which overcomes effectively the problem of other thermal economic matrix equation requiring simultaneous equations on calculating the final thermal economic index. It is versatile and suitable for computerization. Numerical examples show this method is efficient. Figs 3,table 2 and refs 3.

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In this paper, the turbine-generating units installed in Three Gorges Power Plant with the rated capacity of 700 MW are introduced. It is emphasized the parameters, structural features and manufacturing and installation progresses. The results of the two model acceptance tests showed that the efficiency and cavitation characteristics of the turbine reached world-leading level. The first batch of units is expected to be put into operation in Aug., 2003. A series of prototype unit acceptance testes will be carried out at the site.

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Oil, natural gas and coal are the major and depletable energy resources of the world. Trends of these energy resources combined with the total primary energy consumption, national gross domestic product, population growth and associated carbon dioxide emissions of the world during the last decade (nineties) are discussed. Also, discussed are the global electric power generation and gas turbine market. The analyzed data and trends of various parameters reveal that the energy market and related industries are expected to grow, in coming years, comparatively at a higher rate in Asia & pacific and Central & South America regions provided the observed industrial and economic growth of the last decade continue. Even though North American boom for gas turbines in power generation is over, the need for gas turbine is expected to grow in the Asia & Pacific region with the increasing demand for energy there.

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Auxiliary system is important part in thermodynamic system of coal-fired power plant. Based on the research on the characteristics of auxiliary system, and by using the energy balance theory, a general formula for the heat economy of steam-water auxiliary system is derived in this paper. The result of application shows that the calculating method discussed in the paper is more precise and scientific, and possesses the characteristics of convenience and universality use.

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Solid oxide fuel cell (SOFC) shows excellent stability in the material compared with other type fuel cells because electrolyte and electrode of SOFC are chiefly composed of ceramics, and the generation efficiency is expected to achieve over 50%. In addition, it is reported that the generation efficiency is improved further by combining with gas turbine (SOFC-GT combined cycle) by using the feature with the high operating temperature. On the other hand, it is problem that the materials of peripherals and pipes, etc used in SOFC system are restricted and high cost. And the thermodynamic feature is not understood enough about SOFC-GT combined cycle. Therefore, we analyzed the heat and mass balance of SOFC-GT combined cycle based on the experimental data of material developed for low temperature operating SOFC cell. And the influence that some parameters, such as the operating temperature and fuel utilization ratio of SOFC, pressure ratio and turbine inlet temperature (TIT) of GT gave generation efficiency was examined to understand the thermodynamic feature of SOFC-GT combined cycle. We could obtain some results about characteristic of SOFC-GT combined cycle.

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The world's population is expected to increase to ten billion in the 21^<st> century, accompanied by a rapid increase of energy consumption. This will bring about a shortage of fuel resources and global warming caused by CO_2 emissions. The basic solution to these problems will be to use energy resources more efficiently and to switch from fossil fuels to nuclear energy and renewable energy. On this purpose in this paper we will propose the hydrogen-fired Rankine cycle as similar to (C) type and then we will make modification of it by increasing the performance characteristics and efficiencies with (reheating, regenerative and recuperation) of the working fluid of the bottoming cycle respectively, and in this case we will present two types (C1 and C2). In case of type C2 the cycle will be called as "New Rankine Cycle". And as well these cycles will be compared with the Rankine cycle (C) for hydrogen-fired, to show the advantages of the performance characteristics of the new design which the highest value of exergy efficiency can be reached to 63.58% as HHV at 1700℃ of the combustor discharge temperature. These cycles will be analyzed by thermodynamic theory as well as for exergy analysis, and the performance characteristics of the cycles will be studied. The effects of the different parameters such as the discharge temperatures and pressures of the combustors of high and low pressure and also the effect of pressure of the condenser on the performance of the cycles will be also clarified.

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To estimate environmental impacts through the entire life cycle of any industrial activity like co-generation system (CGS) operation, Life Cycle Assessment (LCA) has been found to be a powerful tool. Therefore the authors have first proposed a standardized method called the LCA-NETS scheme (NETS : Numerical Eco-load Total Standard) based on objective data, in which a new unit of [NETS] is used for the standardized numerical value of eco-load, and second developed a new version software of the LCA-NETS scheme for analyzing numerically the eco-loads from a specified CGS and then minimizing the impacts due to the CGS operation. As a result, the LCA-NETS eco-load evaluation scheme constructed here is found to be an attractive and powerful tool to analyze the quantitative LCA environmental loads for any type of co-generation system and to predict its most ecologically and economically optimized operation scheme, resulting in compromising compatibility between eco and cost performance.

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This paper describes about life cycle evaluation of two kinds of power generation system which are using major resources of energy in Thailand between using natural gas and coal. Those power plants hold the share of Electricity Generating Authority of Thailand (EGAT) about 52.5% and 22.7% respectively classified by gross electricity production and by the type of fuel used in 2000. Therefore, it is necessary to understand the environmental influences from electricity production systems, in which could be instructed the component of environmental plan for reducing emissions and resources consumption. The aim of the study is to apply Life Cycle Assessment (LCA) with Numerical Eco-Load Total Standardization (NETS), which is used for evaluating the environmental burdens by identifying and quantifying energy and materials used and waste released to environment. And the Life Cycle Inventory (LCI) and Life Cycle Costing (LCC) of the power plant systems have been developed and estimated. As a result, the LCA-NETS point of view was discussed for further ecological power generating systems which will be acting more environmental friendly in the future.

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The main design parameters and process diagram of the first wet limestone/gypsum FGD plant in Guangdong province are introduced, problems met in the course of operation are analyzed emphatically. Optimization of the FGD systems is researched and carried out gradually, which simplifies FGD plant and lower the cost, meanwhile safety and reliability is also improved.

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Chugoku Electric Power Co., Inc. and Heavy Mitsubishi Heavy Industries, Ltd. developed a new type of absorber, the Double-Contact-Flow Scrubber (DCFS). DCFS is an easily maintainable absorber of simple construction with low initial cost and low power consumption for the wet limestone-gypsum flue gas desulfurization process. Absorbent slurry is spouted up from special type of nozzles located at the bottom of the absorber, creating a pillar of absorbent slurry to achieve a good gas-liquid contact. The only internal components of the absorber are the header pipes and nozzles, resulting in the simplicity of construction with lower cost, as well as easy maintenance due to the lack of scale deposits. This paper shows the performance results of DCFS operation.

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The pore size distribution of 4 kinds of shells and 2 kinds of limestone as SO_2 absorbent were measured with pore master mercury porosimeter, and the desulphurization characteristics of above absorbents were studied with thermal-gravimetric analyzer. As a result, the shell lime has higher pore volume with pore diameter above 0.1 micron, while limestone has lower pore volume with pore diameter between 0.008 to 0.2 micron, but the surface area is very high. The bigger pores whose diameters are above 0.1 micron in shell have fewer air-blocked pores, lower gas diffusing resistance, and almost simultaneous and completed reaction. So, the calcium conversion ratios of the shells are greater than those of the limestone. From the test, the shells that have bigger pore size got higher calcium conversion rate, and within the shells, the S3 shell has the best sulphation ability as its bigger specific surface area.

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Experimental studies are carried out with medium hot-state facility of flue gas desulfuriztion of circulating fluidized bed. Based on the experimental results, mass balance and the chemical reactions taken place in the reactor, a mathematical model of desulfurization efficiency in CFB-FGD system is established. The relationship between the ratio K_<ca(oh)2> of hydrated lime reacted with SO_2 and the difference of dew point and the temperature of the flue gas is given by combination of the experimental results and the mathematical model. The calculating and experimental results show that the model can be used to give better prediction for removal efficiency of the CFB-FGD system. The results also demonstrate that main factors on removal efficiency are the temperature of the reactor, ratio of Ca/S, and the concentration of the circulating materials. On the basis of the calculating results, it is recommended for the concentration of circulating material to be selected as range between 800-1200 g.m^<-3>

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The SCR De-NOx commercial system for coal fired boiler exhaust has almost 22 years history. The Catalyst poisoning by Arsenic oxide vapor was found first in an European SCR test plant. Arsenic in coal is vaporized as its oxides and almost all of them are adsorbed on the ash surface but a very small of the remainder makes the serious catalyst retardation. According to the progress of SCR technologies, catalyst retardation kinetics is required for the catalyst life estimation in coal fired SCR even for the high amount of Arsenic containing region. We studied the Arsenic poisoning kinetics in laboratory scale tests and found the good accordance with the actual exhaust data. The obtained Arsenic deposition (L) and the activity deterioration (k_0/k_<obs>) are expressed as follows.

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