This paper describes R&D study of an internally finned tube aiming at an application to small-scale smoke-tube boilers. An enhancement of heat transfer of smoke tubes provides the possibility of size reduction of boilers, and in addition, a significant contribution toward efficient use of energy, e.g. through latent-heat-recovery technology. Developed internally finned tube consists of multiple aluminum plate fins aligned in parallel across the tube cross-section. Experimental investigation was conducted with a wind tunnel, and local heat transfer coefficients were measured. Various types of fin geometry were examined, and the split-fin type with baffle plates gave very high heat transfer performance. The enhancement in heat transfer was mainly caused by the edge effect and resultant suppression of boundary layer development by splitting fins in several units as well as the mixing and/or agitation of the gas stream across the cross-section. The number of heat transfer unit, NTU, being actually a heat transfer rate, reaches around 15 times of the bare tube without internal fin. This demonstrates high potential of the developed internally finned tube for an application to industrial smoke-tube boilers.

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The efficiency of heat transfer η, i.e., the ratio between heat transfer enhancement and drag increase from the smooth channel, is discussed for the turbulent and laminar flows in a channel with a wing-type vortex generator (VG) installed on the wall. In this report, the effect of Prandtl number Pr on η is mainly discussed. Various effects on the heat transfer enhancement are investigated by using the results of direct numerical simulation and the energy equations integrally averaged over the whole flow field. η decreases slightly in the turbulent flow with Pr while it increases noticeably in the laminar flow. In the turbulent flow, the temperature fluctuation in the smooth channel is suppressed by the strong thermal diffusion effect at low Pr. The fluctuation promoted by VG becomes effective relatively in such region. In the laminar flow, on the other hand, since there is no background turbulence in the smooth channel, the fluctuation generated by VG directly enhances the heat transfer, which is greater in high Pr region where the thermal diffusion effect is weakened. In addition, the increase of convective heat transfer near the wall has an important effect on the good efficiency for the laminar flow.

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Experimental investigation of heat transfer and friction factor behaviors in a rectangular channel with multiple twisted tapes (MTTs) is carried out. In each run, five MTTs are simultaneously used as the swirl flow generators in a test section. The lower wall of the channel is subjected to uniform heat flux conditions while the upper wall is insulated. Parametric runs are made for Reynolds numbers ranging from 2700 to 9000, the tapes with twist-length to twist-width ratios (y/w) of 3, 4 and 5 while the aspect ratio of AR = W/H = 10 is fixed throughout. Experiments using smooth channel are also performed for comparison. The experimental results reveal that heat transfer in the channels with MTTs at twist ratios (y/w) of 3, 4 and 5 are respectively increased around 55%, 37% and 22% over those in the smooth channel. In addition, the empirical correlations of the Nusselt number and friction factor in the developed flow region for the channels fitted with MTTs are also derived.

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Experimental investigation have been performed on natural convection of air over an upward facing, inclined, heated plate. The special interests were paid to the turbulent transition and the heat transfer characteristics. The flow fields over the plate were visualized with smoke. The results showed that longitudinal vortices appear first in the laminar boundary layer when θ < 72°. Then, the vortices detach from the plate and become distorted, and, finally, a fully turbulent state is accomplished at far downstream of the plate. Local Nusselt numbers from the plate were also measured. The results showed that the numbers deviate from the laminar values with the formation of the longitudinal vortices and, then, increase significantly with the detachment of the vortices. Based on these results, empirical correlations for the laminar and turbulent heat transfer by natural convection were proposed.

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The objective of this study is to clarify performances of a method for heat transfer enhancement using porous material with high porosity by an experiment. The experiment has been performed using an apparatus which simulated the passage structure of the steam reformer to obtain characteristics of heat transfer and pressure drop. From the results obtained in this experiment, the heat transfer rate by this method showed a good performance in the laminar flow region. It was also found that the method for heat transfer enhancement using porous material with high porosity is further improved under the high temperature condition as compared with the other methods for heat transfer enhancement.

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In this present work, the influences of the porous twisted tape (PT) on the heat transfer and the pressure loss are studied experimentally. The comparative experiments are conducted in the tube fitted with the PT or typical twisted tape (TT) at different twist ratios, y/w = 4.0 and 5.0, in the Reynolds number ranging from 4800 to 16,000 under uniform heat flux conditions. In the experiments, the PT inserts generate swirls that modify the near wall velocity profile resulted in improvement of the heat transfer rate. The experimental results reveal that the heat transfer rates increase with decreasing twist ratio (y/w) for all twisted tapes used in the experiments. The heat transfer rates increase up to 71% with the help of the PT. The increases in average Nusselt numbers of using PT and TT are found to be 48% and 22%, respectively, over those of the corresponding plain tube. However, PT causes a considerable increase in friction factor. The mean increases of friction factors for PT and TT are respectively, about 3.14 and 2.45 times in comparison with that for the plain tube. Mean friction factor and Nusselt number for PT, are respectively 28% and 21% higher than those for TT. In addition, the empirical correlations of the Nusselt number and friction factor are also reported.

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Multilayer flow insulation is proposed to improve the performance of single layer flow insulation. Dividing a single porous layer, open-cellular porous materials, into multiple porous layers is always effective to obtain a large gas temperature drop ΔT_f across a flow insulation system. The energy equation of the gas and of the solid phases is employed by using separate energy equations model, and the convective heat transfer between the two phases based on an empirical volumetric heat transfer coefficient proposed by Kamiuto and San San Yee is estimated. The P_1 approximation is used to evaluate the radiation of transfer equation. When an equivalent blackbody radiation temperature of the radiation coming from the upstream region exceeds an inlet gas temperature, use of a high reflective porous plate on the upstream side and a low reflective porous plate on the downstream side is quite effective to increase ΔT_f.

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Three-dimensional numerical calculations have been performed on liquid-metal MHD flow through a circular pipe in the outlet region of a magnetic field. The continuity equation, the momentum equation and the induction equation have been solved numerically. The induction equation is derived from Maxwell's equations and Ohm's law in electromagnetism. The discretization of the equations is performed by the finite difference method, and the solution procedure follows the MAC method. Calculation results have shown that along the flow axis, i.e. the circular pipe axis, the pressure decreases steeply as a fully-developed MHD flow, drops more sharply in the magnetic-field outlet-region, and finally decreases slowly as a normal non-MHD flow. The flow velocity distribution changes from a flat profile of a fully-developed MHD flow to a parabolic profile of a non-MHD laminar flow in the outlet region of the magnetic field.

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This study clarified appropriate reaction conditions for the thermal decomposition of glycerol to H_2, CO, and hydrocarbons to utilize waste glycerol derived from biodiesel production. The effect of reaction temperature on gaseous products was examined through experimentation and chemical equilibrium simulation. In addition, the effects of steam addition and partial oxidation were also investigated. The results indicated that both steam addition and partial oxidation are effective methods for improving gasification efficiency at a relatively low reaction temperature, and the heat value of the products is decreased when partial oxidation is employed.

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PVC in the plastic-impregnated MSW (Municipal Solid Waste) is creating problem when being used as solid fuel due to its high chlorine contents. An innovative hydrothermal technology is being developed to overcome the problem by applying middle-pressure saturated steam at about 200℃ in a stirred reactor for certain holding period. Experiments on a commercial plant of 1 ton MSW capacity per batch using plastic-impregnated MSW in Japan produced treated MSW in slump form which was easily dried, with the end product of less than 10% moisture content and about 20MJ/kg (db) heating value material in powder form. Product analysis showed that the organic chlorine content of the product was reduced from about 1% (dry base) to less than 0.2%, being converted to inorganic (water-soluble) chlorine. The phenomenon was shown to be apparent in higher treatment temperature. The inorganic chlorine can be removed afterward by water washing.

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Technologies of reduction in power consumption for vertical roller mills have been developed using fundamental classification test devices and Computational Fluid Dynamics, and the effect on power reduction was evaluated using a pilot scale mill, grinding capacity of which is 2t/h. In order to suppress needless recirculation of fine particles in the mill, which causes over-grinding, performance of the primary classification by gravity force and the secondary classification by centrifugal force was improved. For the primary classification portion, a new rotating nozzle ring with reverse swirling flow, which can achieve sharp classification, was developed. For the secondary classification, a new rotary classifier with a deflector ring and a louver separator was developed. Results of the pilot scale mill tests showed that the power consumption of a latest mill applying the developed technologies was approximately 20% lower than that of the conventional one.

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Flame spray pyrolysis technology makes use of the high chemical activity of a flame. A metal salt aqueous solution or slurry is used as the starting material and is atomized into a flame or furnace. The solvent in the sprayed minute liquid droplets evaporates, pyrolysis occurs, and then solid particles are sintered. We focused on the spray pyrolysis method for preparation of LSM/ScSZ composite powder for use as the SOFC cathodes. We utilized a gas combustion system as the heat source that is characterized by the fact that its operation costs can be much less than that of conventional electric heating systems. On the other hand, in-flame treatment technology uses the high-temperature environment within a flame. The starting material is used fine ceramic powders, and is introduced directly into an oxygen flame to be melted. The technology related to in-flame melting of ceramic powder, which has already been established, is a typical example of this type of technology, which is based on the principle that a material is melted within a flame and spheroidized as a result of its surface tension.

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The experimental studies on the optimization control of combustion and unit load have been performed using radiative energy signal (RES) based on a visual monitoring system of three-dimensional (3-D) temperature distribution installed on a 660 MW arch firing (AF) coal-fired utility unit. The results show that: (1) Real RES changes linearly with the unit power. The RES under different unit power is recommended to be controlled close to the linear fitted value of corresponding load as much as possible. (2) During the stage of load increasing or decreasing, the radiative energy should be strictly controlled within a reasonable range. (3) When the load is less than 500 MW, optimizing air flow by using RES can increase the net unit power of 5〜10MW with the same coal flow rate. It is potential to use RES for optimized combustion control of large-scale coal-fired utility units.

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The slag of blast-furnace produced by Kunming Iron and Steel corporation in Yunan province was used as raw materials together with mineral materials such as quartz, feldspar, fluorite, dolomite, calcite and other chemical reagents such as sodium hexametaphosphate and Cr_2O_3, to prepare glass-ceramics by melting method. The major crystalline of the glass-ceramics was Diopsid (CaSiO_3) and diopside (Ca-Mg(SiO_3)_2) ranules of which are thin small, are close and e evenly distribute; XRD together with SEM was used to characterize the phase composition and microstructure of the glass-ceramics, and some other physical properties of this material were also examined. The effect of nucleation agent, heat-treatment parameters and the content of the blast slag in raw material were discussed. The properties of the glass-ceramics can also be promoted by optimizing the heat-treatment parameters. The optimal heat-treatment parameters in this paper are: annealed at 600℃, nucleated at 840℃ for 1h, then crystallized at 910℃ for 1h. The proper rate for heating is: 5-10℃/min before 840℃, 3-5℃/min between 840℃ and 910℃. Correlative testing results of glass-ceramic made of the high temperature molten slag of blast-furnace reveals that the radioactivity is low and in line with GB; the average Micro-hardness is about 764 kg・mm^2, the average compressive strength is about 587 MPa, average flexural strength is about 46.9 MPa, and corrosion resistance is much higher than marble's and granite's.

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The purpose of the present study is to clarify both the reduced surface tension and the pipe diameter effects on two-phase flows in horizontal small diameter pipes. In the experiments, four-kinds of test liquids with different fluid properties were used together with 3, 5 and 9 mm i.d. test pipes. The parameters studied were flow pattern, bubble size, liquid film thickness, void fraction and pressure drop, etc. The flow patterns covered were bubbly, slug, churn, and annular flows. From the measured data, the data of interfacial friction force per unit volume, F_i, was also obtained. In the analysis, firstly the reduced surface tension and the pipe diameter effects on the flow parameters have been studied by comparing data obtained in different pipe and test liquid combinations. Secondly, mean liquid film thickness and interfacial friction factor in annular flow has been correlated with some dimensionless groups.

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The oscillation of pipes containing two-phase flow is very important not only for the design of heat exchangers but also for the estimation of flow behavior by detecting the vibration or noise transferred from sounding rod pressed to the components. The skilled engineers sometimes can estimate the two-phase behavior with vibration or noise from components such as heat exchangers or steam generators. To understand the oscillation behavior and possibility to estimate the flow behavior, the air-water two-phase flow experiments were conducted with small vertical tubes of 2 and 11.5mm in inner diameter. We have been presumed the quality of two-phase flow used pressure difference fluctuation and liquid flow rate. In this study, vibration of pipe was extracted directly and presumption of quality or flow pattern of two-phase flow was tried.

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A new type of desulfurization absorber with double-contact-flow has many advantages on operation and maintenance. The flow regimes of gas-liquid two-phase flow and their transition in this kind of absorber are investigated and analyzed. Using the direct observation method, the probability density function (PDF) method, and the bed expand method, the macroscopical flow characteristic is recorded. And the pressure fluctuation of different flow patterns is measured. With the increase of liquid gas ratio, four flow regimes are detected and identified, which are liquid-column flow, liquid-screen flow, surging flow, and quasi-bubbling flow. The flow regime map of liquid-gas ratio (L/G) versus gas Reynolds number (Re_g) is presented. And hydro-mechanical parameters of flow patterns transition are given.

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A steam generator apparatus was designed employing a method of vaporization that uses falling films on heat transfer tubes, thereby rendering the size of the generator to become more compact. Surface-worked copper tubes were selected for high evaporation performance. The tubes were set in a steam generator having a layout of three lines and twenty layers. An electric heater was equipped in each of the heat transfer tubes as the heat source. The water flow rate for falling films was set appropriately. As a result of the experiment, it was found that the heat transmission coefficient of this method was larger under the condition of low heat flux. However, deterioration of the heat transmission coefficient was observed under the condition of high heat flux. Accordingly, an experiment of vaporization by pool boiling was carried out using the same heat transfer tubes under the high heat flux condition. From these experimental results, the size of the steam generator was determined.

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A new methodology based on the use of CFD is proposed to estimate the energy consumptions in a DTS (DOUBLE-TUBE-SOCKET) pneumatic conveying. A simple computational program based on this methodology is developed. It can directly give the lowest energy consumption and the compatible gas consumption by only input the distance of conveying and the conveying tonnage. This computational program has been validated through our experimental work.

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Temperature -Capacitance relationship was investigated using polycarbonate Compact Disc (CD). Ideally, a capacitance of a capacitor would be the same at all temperatures. But in reality, capacitance changes as the capacitance gets warmer or cooler. In many cases, these changes are ignorable but since research is always engage in a very precise experimental value results, determining the capacitance value or dealing with very large temperature swings are must take into considerations. In this study, in the absence of capacitor, the capacitance has been measured. The polycarbonate resins were placed in a small beaker, surrounded by 12 electrodes connected to LCR to measure the capacitance, and heat was continuously applied and the thermocouple placed in the middle of the beaker connected to the tester to measure the temperature in terms of voltages output. The experiment was repeatedly done using different beaker diameter sizes for data comparisons aiming to discuss how the capacitance change with temperature and what is the factor has caused of this change. Using the Electrical Computer Tomography (ECT), the gathered numerical data was used in calculations for image reconstructions using non-iterative Functional Weighted Inverse Matrix method.

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Boiler heat absorption rate is an important parameter for the proper operation and design of circulating fluidized bed (CFB) boilers. It reflects not only work capability of steam-water system but also heat release rates of fuel combustion. The implementation of its online prediction is also very important for improving units' load response speed and regulating level. Based on the real-time and rapidity of image processing, an online prediction model of boiler heat absorption rate was established in this paper, and the economy and safety of units would be improved if the model was applied to units' control system. The model verification experiments were conducted on a super high pressure CFB boiler with a steam capacity of 480 ton/hour. The experiment results show that the predicted boiler heat absorption rate by the model is in general accord with the actual values and the average relative error is 3.424%, so the model could meet the demands of industrial applications.

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A technique for determining the particle size and its concentration in multi-phase flow based on random theory and light scattering theory is discussed here. It is named the fluctuation method because the fluctuating character of transmitted light is used. Based on this principle, a measurement system is established. The latex spheres as Standard Reference Materials (SRM) and samples from industrial processes have been measured by the measurement system. The measured results of SRM agree very well with their marked size. An engineering on-line monitor system has also been developed for pneumatic conveying system in power plants. The monitor test shows that this technique is suitable for on-line monitoring of particle size and concentration in multi-phase flow.

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Flashover is a phenomenon describing a room fire changed from the 'growth stage' to the 'development stage'. There is a rapid increase in size and intensity. In this paper, the gas fire flashover caused by the leakage of liquefied petroleum gas (LPG) is studied by using a series of reduced-sale compartments. The effects of different sizes of compartments and velocities of LPG leakage on flashover are discussed. The results show that the bigger the size of compartment is, the later gas fire flashover occurs; and in the same compartment the larger the velocity of gas leakage is, the earlier the gas fire flashover occurs. Furthermore, this paper presents a new criterion number c_f to describe the probability of gas fire flashover. The result is that if c_f is more than the upper critical value, it's most probable that gas fire flashover occurs and if c_f is less than the lower critical value, it is almost impossible that gas fire flashover occurs.

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The fire triggered by the leak of combustible gas is a serious threat to the public and firefighters. Backdraft is a special fire phenomenon in a limited-ventilation room. This paper reports preliminary numerical simulation of backdraft phenomenon observed in a reduced-scale experimental compartment which has different openings. A sub-grid scale model for partially premixed combustion was applied to simulate the backdraft phenomenon. The analysis was performed with a hybrid of Large Eddy Simulation (LES) and Reynolds-averaged Navier-Stokes (RANS). The results from numerical simulation accord well with the experimental results, which means that the research method of numerical simulation is reasonable.

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In this paper, the fire phenomena of compartment in YW25K train with different velocities is simulated and investigated by using Large Eddy Simulation (LES), Smagorinsky-Yoshizawa Mixed Sub-grid Scale model (SGS) and the mixture-fraction combustion model by the infinite fast chemistry kinetics. Based on the relative velocity theory, the different train running speeds are provided by the simulated wind tunnel velocities. The expanding of fire, the smoke movement and the temperature distribution in the compartment are analyzed. Some recommendations for better fireproofing design and safety management of train compartment are obtained.

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In this paper, the results are presented on the partial thermal load performance tests of multi-type air-conditioners for buildings. We tested two types of air-conditioners, heat pump driven by electric motors (EHP) and that driven by gas engines (GHP), with a rated cooling capacity of 56 kW. The coefficient of performance (COP) and the annual energy consumption measured by those tests were closely compared with those predicted by JIS. In EHP, the measured COP attains the maximum under the indoor thermal load ratio of 50 %, while COP in GHP decreases gradually as the thermal load ratio is decreased. Based on these results, we examined the accuracies of COP and the annual energy consumption predicted by JIS. We found that in both EHP and GHP the current calculating method prescribed in JIS could not reproduce the deteriorations of COP that appeared under the low thermal load conditions. As a result, the annual energy consumption is seriously underestimated by JIS.

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Air-to-water heat pumps using CO_2 as a refrigerant have been developed. In addition, water heating systems each of which combines a CO_2 heat pump with a hot water storage tank have been commercialized, and are expected to contribute to energy saving in residential hot water supply. In this paper, the system performance of a water heating system is analyzed under a daily change in a standardized hot water demand. Especially, parametric studies are conducted by changing ambient and operation temperatures as well as magnitude of change in hot water demand. Some features of the temperature distribution in the storage tank and the system performance criteria such as heat pump coefficient of performance, storage and system efficiencies, and volumes of stored and unused hot water are clarified.

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This paper introduces an integrated system that can achieve the multi-functions with improved energy performance. This system, which is applicable for bathroom can run three different cycles and perform six modes. A series of theoretical investigations were conducted to develop a design criterion for the new systems. The rough cost estimate indicated to have good market prospect due to a little cost increase. A prototype of the system was tested in a national-standard laboratory under relative Chinese standard. The experimental results showed that the mean coefficient of performance for the system reaches 4.22 when it worked as heat pump water heater. Also its dehumidification capability reached 1.29L/h, higher than the limit of the standard of dehumidifier. It certainly achieved the heating/cooling capacity requested on the standard of room air conditioners and the energy efficiency ratio was 2.64.

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In this study we illustrate the fundamental characteristics of a magnetocaloric heat pump using air as a heat transfer fluid concerned with the heat transfer characteristics of an active magnetic regeneration (AMR) cycle. The basic components of the target system are a magnetic circuit, a test section, a fluid supplying system and an associated instrumentation. Spherical gadolinium particles are used as magnetic working substance, and also LaFeSi type magnetocaloric powder coated particles are produced as magnetocaloric materials (MCMs) by powder coating apparatus, to validate the effectiveness of the coating particles. Temperature profiles under several operating conditions for the AMR are measured experimentally. The results show that the AMR cycle is effective for improvement of the performance of a magnetocaloric heat pump, because increase in the temperature span between the hot-end and the cold-end due to regeneration is realized. LaFeSi coating particles also showed the temperature differences in the AMR cycle.

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Through experimental research of the performance effect about the heat source temperature to silica gel-water adsorption chiller, the results obtained show that with temperature increasing refrigerating output will grow, but increment rate is variational; and when the heat source temperature rises, the variety of COP is a wave curve, so COP value comes into being two wave crests and two troughs. With further studies on the microstructure and shape of silica gel, the investigation proves that the micropore of silica gel is mostly "inkbottle" shape, and the distribution of micropore diameter is well-regulated. The results show the adsorption-desorption hysteresis should be sufficiently taken into account when designing or appraising the silica gel-water adsorption chiller. It is also indicated that the micropore diameter of silica gel would match with heat source temperature when designing the experiment.

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Regional air conditioning mechanism (RACM) system is an energy saving equipment, which can control the airflow in a room for the purpose of achieving a regional steady-state temperature. With this concept, each staff in a different area of the location can be satisfied with respect to their own local environment. The RACM was constructed of a main duct inlet-outlet round ports. The purpose of this paper is to study the effect of air inlet velocity, outlet vacuum pressure, and distance between outlet port and floor surface to obtain an optimal airflow circulation cell, temperature distribution, and thermal comfort indices in occupied zone of the room. Moreover, the computational fluid dynamics (CFD) model was validated on the basis of the experimental results. It was found that the simulation results were in good agreement with the experimental data. The CFD can predict very well the RACM and reveal the effect of operation parameters on the airflow circulation cell that is directly related to its performance. Besides, the RACM inferred more energy efficient than a typical air conditioning system. The results will be valuable bases to research and design the RACM system to all kinds of regional air conditioning in any enclosed space.

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A multi-stage optimal renewal planning method is proposed for an energy supply system installed into building from economic viewpoint. Based on the annualized costs method, the average annual total cost during the total evaluation period is formulated as the objective function to be minimized. This is formulated as one of the mixed-integer linear programming problem, and the numerical solution is carried out by using the GAMS/CPLEX solver. A numerical study is carried out for an energy supply system installed into an office building with total floor area of 15 000m^2, and the optimal renewal system is proposed as the one of installing high performance equipment properly at each optimal renewal year.

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A geothermal heat pump (GHP) heating system is one of the most promising alternative heating systems for cold regions such as Hokkaido, the northernmost is land of Japan. Thermal demand during heating seasons from 2005 was measured and simulated for a residential house installed with a GHP air-conditioning system that had a U-tube with a depth of 91 m. It was demonstrated that heating was fully supplied by the GHP system alone for four years. Soil temperature distributions around the U-tube were measured in order to establish criteria for ground capability as a heat source. The results showed that soil temperature reduction during the entire heating season was limited to within a radius of about 5 m from the U-tube. This means that a U-tube must maintain distance of about 10 m from an adjacent U-tube which gives a similar thermal gain. Accumulative geothermal absorption during heating season did not fully recover during non- heating season even with external thermal input to the ground by free cooling.

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Temperature and temperature shock have been a kind of key factor to influence the digestion process stability in anaerobic digesters in cold climate, especially using energy crops in the feedstock for its selfheating. Firstly, it is described the energy application in the multiphase flow field of anaerobic digester, such as the heat energy supplied by burning biogas from itself as fuel, solar energy, the traditional biomass energy, geothermal energy and etc. Secondly, this study constructed a new pattern of ground-source heat pump heating integrated system to compensate the lost temperature of the digester and maintain the operation process stability in cold climate. In the meantime, we get the preliminary result about the average tank volume aerogenesis rate of the system, the culmulative electricity cost, the culmulative biogas yield in the mathane tank at different time. Lastly, it was discussed how to keep the stability of the temperature field in mathane tank depending on practice covered how to select a optimum digester temperature setting and a reasonable temperature increase, how to adjust the heating system, to keep energy balance and to estimate feasibility of reactor system.

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The main objective of this work is to investigate the influence of scrubber parameters on mercury re-emission to establish effective measures for mercury removal. The effects of key parameters, such as gas components (N_2, O_2, CO_2, SO_2, NO, NO_2), slurry temperature, gaseous mercuric chloride (HgCl_2) concentration, different slurry solution (water, KCl, KOH, Na_2S and Ca(OH)_2) and even the scrubbing process of the lab-scale scrubber experimental testing were carried out. The results obtained point to SO_2 as the most critical parameters for inhibition of mercury re-emission and other variables appears to impact on re-emission.

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This paper provides details concerning emissions of mercury and other trace elements conducted at a coal-fired power plant with SCR and wet FGD. Mercury emission concentration and its speciation were measured with Ontario Hydro Method (OHM) and Semi-continuous emission monitor (SCEM). The emission of trace elements was determined by EPA method 29. Mercury mass balance and partitioning of trace elements were analyzed based on the analyses of solid samples (such as: coal, bottom ash, fly ash, and flue gas desulphurization (FGD) slurry) and concentration of trace elements in the flue gas. The results indicated that total mercury (Hg^T, sum of Hg^0, Hg^<2+>, and Hg^P) remained relatively constant along the flue gas path before passing through FGD. The ratio of Hg^<2+> to Hg^<VT> increased from 45.7% to 83.3% after flue gas passed through SCR. Hg monitoring methods of OHM and SCEM agreed that over 95% of Hg in flue gas was in oxidized form before FGD. The mercury removal efficiency of FGD was more than 96%. A better ratio of Hg output to Hg input (within the range of 0.8 to 1.2) was obtained while Hg content in ashes reached a dateable level. The emission concentration of each element was very low, and the change of the gaseous phase compositions of the selected trace elements was found insignificantly throughout the flue gas path. Mercury and Selenium are almost fully released in the gaseous phase. The main proportion of other trace elements is bound with the fly ash and collected in the electrostatic precipitator (ESP).

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The simulated flue gas carrying mercury generated with special mercury generator enters into a multiphase flow reactor with different modes and the mercury sorbent was injected into the reactor at different rates and modes to study the effect of the flow characteristics and sorbent injection modes on mercury removal efficiency in flue gas. The studied results have demonstrated that different flow characteristics in the reactor affect the mercury speciation distribution in the flue gas, and it also affects the mercury removal efficiency. The possible reasons are that different flow characteristics makes the contents in the flue gas be with different resident time in the reactor and affects the chemical reaction between the contents with mercury, so that mercury speciation distribution in flue gas changes. The results will help improve mercury removal efficiency through optimizing the flow field in the duct so as to reduce mercury pollution emission in the flue gas.

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Long-term exposures to diesel particulate matter (DPM) emissions are linked to increasing adverse human health effects due to the potential association of DPM with carcinogenicity. Current DPM emission regulations are based solely upon total mass concentration, albeit it is the sub micrometer particles that are highly respirable and the most detrimental to human health. The electrostatic scrubber efficiency was measured under various engine loads. In addition, DPM collection efficiency was found to be directly related to exhaust gas capacity, the charge to mass of the water, water electrical properties and water spraying performance. The effect of the scrubber on the collection of DPM was investigated experimentally. The fine DPM which have diameter between 0.1 and 2.5 microns are removed at very high efficiency by highly electrical charging to the water droplets and DPM in opposite polarity. Simultaneously, all soluble acid and caustic gases are removed at the same levels as those of conventional scrubbers. Even though the primary mechanisms of scrubbing of DPM are known, the exact mechanism is not understood yet. Prediction of DPM collection efficiency is very important to evaluate pollution control of equipment. Hence verification of the overall efficiency achieved by any spray scrubbing system based on theoretical models is essential. In this paper an attempt has been made to theoretically predict the efficiency for an electrostatic water spraying scrubber. Results indicate that a maximum of overall collection efficiencies for fine DPM from marine diesel engine over 97% of all particle sizes and it allowed decreasing the water consumption up to about 4〜5 times. A comparison of the experimental and theoretical efficiencies has been made and systematically analyzed.

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Selective catalytic reduction (SCR) is a prospective way to reduce NO_x emissions from combustion devices. The aim of this study is to develop a SCR catalytic filter device for diminishing NO_x and soot emissions simultaneously among exhaust emissions from various combustors. Catalysts are used to reduce NO_x emissions in a SCR catalytic filter device and catalytic filters inside it are specially designed and constructed to diminish soot particles. NO_x emissions react with ammonia on the catalyst surface of SCR device to produce a harmless matter in the range of reaction temperature. The amount of ammonia must be optimized with the amount of NO_x. If the amount of ammonia is much higher than that of NO_x, the ammonia slip will be formed. The ammonia to a certain amount in the atmosphere leads to some diseases for human. Hence, a flow uniformity of ammonia in front of SCR catalytic filter is a challenge to obtain a higher NO_x conversion and lower ammonia slip. In this study, three dimensional CFD simulations are performed to investigate the ammonia mass concentration (distribution) in a SCR catalytic filter device. Three catalytic filters with 120° intervals are vertically mounted on a horizontal plate. A heater is located at the bottom wall inside SCR system to heat up the gas for achieving the reaction temperature (temperature window). Ammonia is injected radially perpendicular to the inlet main flow and mixed with the exhaust gases. Ammonia is distributed convectively to the cavity of SCR catalytic filter device. It is found that the circulation causes ammonia concentration difference in the core. The high and low ammonia mass concentrations are observed in the core. This circulation restricts the transport of ammonia from the core to the outside. The mixing index decreases as increasing the heating temperature in the SCR system.

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It is required to develop the medical waste management system with non-burning treatment and safety functions for the small medical institutions. In this paper, the treatment of the medical waste without oxygen injection has been achieved with hybrid heating by microwave power and electric heater. A shape of a reactor is a rectangular parallelepiped and its volume is about 0.1 m^3. The plastic syringe with a volume of 20 mL was used for the waste samples. In the experiment, three typed treatments such as hybrid heating, microwave heating and electric heating have been investigated for medical waste treatment. Two shaped stainless steel containers like tureen and flat dish were also examined to compare treatment efficiency and/or to avoid an attachment of melted plastic material on the bottom of the reactor. The plastic syringes were completely treated with only the hybrid heating, whereas the electric heating made the waste melt without a reduction of the weight.

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In the condition of high heating rate, studing on phosphogypsum reductive decomposition by novel reducer. The article study novel reducer high-sulfur coal and coal gangue's reactant ratio, sizes of raw material, reaction temperature effect phosphogypsum decomposition sulfur dioxide's concentration and the main composition calcium sulfate's the rate of decomposition and desulphurization. The results show that the best reaction conditions are C/S molar ratio is 0.7, high-sulfur coal and coal gangue' size of raw material is 100×10^<-9>m^3, the temperature is more than 1000℃. There are the best reaction results in this condition. The concentration of sulfur dioxide is more than 20%. Phosphogypsum's the main composition calcium sulfate's the rate of decomposition is more than 90% and its desulphurization is more than 85%. These provide technology parameters and theory basis for high sulfur coal and coal gangue reduction decompistion phosphogypsum to preparation high concentration sulfur dioxide. These can solve the problems of the current process and system. The first problem was the concentration of sulfur dioxide is low and great fluctuation. The second problem was the cost of making acidic is high. At the same time solid residue can act as the raw of the production of cement.

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Usually, Trichloroethane has been used for the de-oiling and cleaning of machine parts. But its production and import have been prohibited since 1995 because of its possibility to destroy the ozone layer. Generally for biological and environmental safety, the de-oiling should be done with the physical method instead of the chemical method using detergent or solvent. As one of the physical method, a cleaning by a flashing water flow through a packed bed of machine parts has been proposed. The hot water was injected and flashed into steam and water in the packed bed kept at the low pressure less than an atmospheric pressure. In the present study, a prototype flashing water cleaner was designed and its de-oiling ability was experimentally investigated with different sizes of bolts and nuts as oily machine parts. The de-oiling ability was strongly affected with the newly-defined non-dimensional parameter consisting of the injection duration, the average kinetic pressure of flashing two-phase flow defined at vacant container flow area and viscosity of oil. The de-oiling rate more than 95 % was successfully achieved at the parameter larger than 24.

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Fuel filtration for ship and power station application is still of great importance for a reliable and cost-saving operation of diesel engines. This paper is focusing on the newest large 4-stroke and 2-stroke engine designs which have high-level requirements in fuel filtration. We will point out the necessity to have the best possible technical solution for fuel oil treatment with regard to removal of harmful solids as well as to use equipment with design features, which will stay at its initial high level. BOLL & KIRCH uses the newest quality-controlled design and methods of fault analysis, computational fluid dynamics (CFD) and efficient tests of all components as well as pilot production and final field tests to avoid deviations during the serial production. This leads to a new generation of HFO automatic backflushing filters on a very high quality level.

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Seafarers' knowledge and skill have been passed down from people to people on board ships. But recently, it is becoming more and more difficult to pass down the skills and experiments of seafarer to the next generation. Especially, it is very difficult to pass down what we call intuition or tacit knowledge, which is one of the seafarers' knowledge that is acquired only through various experiences on board ship. In order to pass down and maintain those skills and knowledge as much as possible to the younger generations, we propose here the system to collect, sort out and compile database where the skilled seafarers can add and accumulate their own tacit knowledge while working on board. Thereby younger seafarers can have opportunities to learn those skills with their predecessor's actual experiences, the further engineering backgrounds and other applications. In this research, we focus on engine part as our subject.

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The performance of the cooling tower with engineering modification in a 300MW unit was analyzed. The operational data of two cooling towers that one used the air optimization technology and the other did not were investigated and compared. The results show that air deflectors that are fixed around the inlet of the cooling tower can reduce the adverse effect of cross-winds, have good influence on the uniformity of inlet air and then improve the performance of cooling tower. The relative variation of temperature difference as a new theoretical index was given to evaluate the performance of cooling towers under cross-wind conditions. Suggestions were proposed to evaluate the performance of cooling towers in actual operation.

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Cogeneration systems (CGS) are set up in the energy demand site so environmental noise impact must be took care of. If necessary, sound barriers and acoustic absorbents are set up, and the environmental noise impact is assessed for the optimum design. The propagation of noise is calculated by the computer simulation, and the geometry acoustic method is used for the calculation of industrial noises. However, wave phenomenon such as interference and diffraction is calculated with the physical model in this method. Therefore, it is necessary to confirm whether the low frequency sound with strong influence of the wave phenomenon can be appropriately calculated. Then the physical model of the geometrical acoustic method and the wave acoustic method which can, although requiring heavy computation load, calculate wave phenomena were verified by the experiment, and the calculation method that is suitable for the noise influence evaluation of the CGS has been developed.

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