The coal staged conversion process combined pyrolysis and combustion is a promising coal utilization. The aim of this paper was to investigate the inherent minerals and coal ash on sulfur transformation. Raw coal , demineralized coal and the mixture of demineralized coal and ash were pyrolysed in a fixed bed reactor in the range of 500-800 ℃. The results showed that inherent minerals and coal ash could greatly reduced the yields of H_2S at all tested temperatures, and more H_2S was fixed by the presence of inherent mineral, compared with coal ash. The sulfur in tar was also decreased in the presence of inherent and ash. The char obtained at ℃ was burned to determine the SO_2 evolution. Results revealed that coal stage conversion process had an advantage over direct combustion in reducing SO_2 release. It was noticed that inherent minerals had minor effect on SO_2 release, while SO_2 was greatly increased by the presence of coal ash.

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The CeO_2/Fe_2O_3 mixed oxides was prepared by co-precipitation method. The materials containing carbon were obtained by the step of CeO_2/Fe_2O_3 compound reaction with methane for 60min. Raman spectra and TEM was used to study the structure of formed carbon. The carbon oxidations over cerium iron catalysts in the absence or presence of gaseous oxidant were investigated. The Raman results showed that the carbon species exist by the form of high graphitization carbon nanotube. The continuous reactions indicated that the oxidation of carbon on the surface of cerium iron catalyst by air gave complete removal of carbon as carbon monoxide with high selectivity (>90%) at 800℃, and the solid-solid reaction between carbon and CeO_2/Fe_2O_3 mixed oxides should play a significant role to promote the formation of CO in this process. In conclusion, it is confirmed that the selective transformation of carbonaceous species from methane decomposition to valuable CO is possible.

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Acoustic field calculation and measurement is carried out on a three-bladed horizontal axis wind turbine with a rotor diameter of 1.4m. Three different tip speed ratio conditions have been considered. In the simulation part, first the flow field is calculated by solving three-dimensional unsteady incompressible Large-Eddy Simulation (LES) equations using computational fluid dynamics techniques. Then the aerodynamic noise is predicted by applying the FfowcsWilliams and Hawkings (FW-H) equations to the obtained flow field information. A computational framework used to evaluate the aerodynamic noise is developed and validated against the experimental data. The directivity, frequency and turbulent fluctuation characteristics of the aeroacoustics is studied. It is found that mostly the noise will increase with the increase of the tip speed ratio. It doesn't vary with the change of the direction in the rotation plane, while showing fluctuations in the axial direction. In the low frequency section of the noise in the near wake region, rotation noise dominates. There are obvious peaks at the fundamental frequency and integer multiples of the fundamental frequency. The noise energy decreases with the increasing of frequency and distance from the rotational plane.

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Previous research has shown that tip clearance in a low-pressure turbine stage is of practical significance in evaluating the overall loss and off-design condition always occur due to the complex operating conditions. Both of the vortices and operation under low load condition generate strong unsteadiness and oscillating, which may give rise to unreliability of steam turbine. This research mainly focus on investigating the unsteady performance of last two stages with tip clearance in a 100MW industrial steam turbine under design and off-design load conditions. An unsteady numerical simulation was conducted to predict the transient flow properties in the flow field, in which the K-w SST turbulence model has been used. This paper gives the characteristics curve, then the design point and low volume flow conditions were respectively focused on. The scrolled tip leakage vortex and its interaction with the mainstream were analyzed. Correspondingly, the aerodynamic losses caused by the flow near the wall were also shown. Comparison of the transient results under different volume flow conditions was made. The results show that the variation of the leakage vortex varies with time and different volume flow conditions. The structure, intensity and trajectory of the leakage vortexes and other vortexes were captured. The extending of tip leakage vortex stretches and shrinks with a regular periodic process for the leakage flow at tip clearance. Under design condition, the interaction of tip leakage flow with the mainstream was strong. And under low volume flow condition, a reverse flow region was shown and the unsteadiness was stronger because of the presence of many vortexes. The vortexes influence the flow patterns in stages, and the flow patterns give rise to the corresponding aerodynamic characteristics, since the blade load may show the influence of the tip clearance. The conclusions drawn by this paper may provide a reference for the further low-pressure stage blade design of 100MW industrial steam turbine. By numerical study in this paper, the mechanism and consequence of flow with leakage flows were understood more deeply under design and off-design load conditions.

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Based on the different emission standards for main atmospheric pollutants emissions from mobile sources, this paper estimated major exhaust emissions of carbon monoxide (CO), nitrogen oxides (NO_x), hydrocarbon (HC) and fine particulate matter (PM_<2.5>) from on-road and off-road mobile sources in China for the years 2000-2012. The results showed that: (1) Over the 12-year time period, there had been increased and then decreased. And in 2005, the emissions reached the maximum, 42.33 Mt, and the on-road mobile sources shared more than 80% of the total value. (2) Source contributions to these totals differed significantly, with higher contributions coming from CO and NOx, each accounting for more than 87% of the total emissions. In general, the emissions of CO show a tendency of decreasing as the emissions of NOx tend to increase, in contrast, the emissions of HC and PM_<2.5> have small change. (3) The motorized and heavy-duty diesel trucks were typically on-road mobile sources, while agricultural machines were the major off-road mobile sources. (4) The distribution of main atmospheric pollutant emissions among regions differed distinctly. The five-top provinces were Shandong, Guangdong, Hebei, Henan and Jiangsu province in 2012. In addition, the emission extensive intensity provinces were from in Bohai economic circle, Yangtze River Delta region and the Pearl River Delta region. In these areas, the highest emission intensity provinces were Shanghai, Beijing and Tianjin.

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For addressing climate change, China is stepping up its efforts to achieve the target of reducing CO_2 emissions per unit of GDP by 40 to 45 percent by 2020 from the 2005 levels. So it is necessary to estimate China's greenhouse gas (GHG) emissions in details and to analyze its characteristics. GHG inventories of China are estimated from 1991 to 2012, covering energy activities, industrial processes and agricultural activities, and including CO_2, CH_4, N_2O, CF_4, C_2F_6, SF_6 and HFC-23. China's total GHG emissions grew from 3368.8 Mt CO_2 equivalent (CO_2eq) to 10656.3 Mt CO_2eq. The emission from the energy activities grew from 2621.8 to 8665.6 Mt CO_2eq, and the emission from the secondary sector grew from 1925.9 to 7515.2 Mt CO_2 eq. In greenhouse gas type, CO_2 emissions rose from 2591.1 to 9097.5 Mt accounting for the largest proportion. With the complete decomposition model, the change of GHG emissions from industrial sectors is analyzed quantitatively. The results indicate that only the energy intensity effect contributes to GHG emission mitigation, the largest increase is caused by economic activity effect, the structure effect does not achieve emissions reduction, and the emission factor effect is insignificant.

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Experiments were carried out in a self-designed submerged circulative impinging stream reactor in a continuous model aiming at simultaneous desulfurization and denitrogenation. Important parameters were studied and intensively discussed. The experimental results indicated that liquid level was an important factor on the denitrogenation and desulfurization efficiency. The effect of gas flow rate on desulfurization efficiency was weak while the NO_x removal efficiency increased with the increasing gas flow rate. The additional urea had a negative performance on denitrogenation efficiency while the increasing urea concentration showed no obvious improvement on SO_2 removal. The composition of aqueous solution was found to be an important factor on denitrogenation efficiency, which was caused by the mixing effect between liquid and gas. The mixture alcohol amine solution, a kind of surfactant, decreased the surface tension which is benefit for the formation and stabilization of small bubbles. Thus the contact area between liquid and gas increased and the mass transfer ability was enhanced. At optimal operation condition, the average desulfurization and denitrogenation efficiency can be achieved to 57% and 99.8%, respectively. Accordingly, the absorption of nitrogen oxides in ammonia-based aqueous solution shows a promising prospect to control the emission of SO_2 and NO_x simultaneously.

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Taking a 1000MW ultra-supercritical tower type boiler as research object, two-dimensional discrete model is established to predict the heat transfer and wall tube temperature in the furnace, while the convective heat transfer is considered. By comparison to the measured data, the predictive data have a fine accordance, and the maximal deviation is 5.26% approximately, which verify the reliability of this model. Based on the model, the proportion of convective heat flux in the furnace and the effect on wall temperature are investigated. The calculated value of wall temperature increase by 16.7℃ at most under consideration of convective heat transfer, which can improve the accuracy of predictive calculation. Further, under the given load conditions, the distribution of water wall temperature in the primary combustion zone were obtained. The maximal calculated wall temperature is close to 524℃, that is lower than the allowable temperature of material, with a safety margin of 4.8%.

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Numerical investigation was conducted on three-dimensional steady flows in the last three stages of a 100MW industrial steam turbine, by using the commercial CFD software CFX. An equilibrium condensation model was adopted to describe wet steam two-phase flows. The internal flows in blade passages and the structure of leakage flows in blade tip clearances were analyzed in detail under design and off-design operation conditions. The aerodynamic performances of the last three stages under different operation conditions were also compared. To explore the influence of the axial clearance on the aerodynamic performance, the axial relative position was altered between the second and the third stages and the flow characteristics in the blade passages were analyzed under the design condition. The turbine performance parameters varying with the relative axial clearance alteration were obtained. The axial clearance alteration changes the flow development at the outlet of the second stage rotor and then the flow state at the third stage inlet. Too small an axial clearance leads to flow instabilities at the second stage outlet, disturbing the inlet flow of the next stage. Conversely, too large an axial clearance will lengthen the axial size and may cause shaft system vibrations. This paper provides a theoretical basis for choosing the axial clearance between stages of a 100MW industrial steam turbine. Results also show that flow separations occur around the last stage blade due to the negative attack angle under low flow rate conditions. The flow separations in upstream stage passages cause the extension of the separation zones in the next stage flow passages, and the tip clearance leakage flow was correspondingly affected. The diagram of the corresponding relationships between the flow rate and the turbine aerodynamic performance was acquired, the reasons of the flow loss caused by low flow rate conditions were analyzed in detail.

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The conditions for sodium hypochlorite aqueous solution (NaClO(aq)) oxidizing and absorbing gaseous elemental mercury (Hg^0(g)) and nitrogen oxides (NO_x(g)) were examined. First, some chemical thermodynamic parameters for NaClO(aq) removing Hg^0(g) and NO_x(g) were calculated, including the standard Gibbs free energy change ΔG^θ, standard equilibrium constant K^θ, standard enthalpy change ΔH^θ, to theoretically prove the possibility for NaClO(aq) removing Hg^0(g) and NO_x(g). Next, the idea for NaClO(aq) simultaneously removing Hg^0(g) and NO_x(g) was propounded. And a technical scheme for simultaneously removing Hg^0(g) and NO_x(g) in flue gas was designed. Then, to check the feasibility of this technical scheme, an experiment for NaClO(aq) removing Hg^0(g) and NO_x(g) was carried out, a mass transfer model based on bubbling reactors for calculating overall mass transfer coefficient was established, the effects of NaClO(aq) concentration, NaClO(aq) temperature, NaClO(aq) pH on Hg^0(g) and NO_x(g) removal efficiencies and their mass transfer processes were investigated, Hg^0(g) and NO_x(g) removal processes and mechanisms were analyzed.

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The fatigue behavior of 2A12 Aluminum alloy was experimentally studied through different annular notched specimens under symmetrical triangle with the frequency of 0.5 Hz. The experimental result showed that the microstructure played an important role during the entire fatigue life of 2A12 Aluminum alloy. The short fatigue crack only initiated due largely to the second-phase particle such as the S phase (Al2CuMg), the θ phase (CuAl2) and especially the black impurity phases debonding from the basal body when the fatigue cycle was sufficient. Most of crack initiation were related to the oversize particles and affected by the shape and size of the particles. The crack propagated along the slip band of the grains. The propagation morphology presented as a zigzag path in crystallography crack. The computed tomographic images were improved with image processing including contrast enhancement and outliers remove. These image processing procedures and three-dimensional reconstruction method were integrated into self-programming by using Matlab. The reconstruction result showed that the size and morphology of three-dimensional reconstructed crack had a satisfying agreement with the experimental ones.

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MILD oxy-fuel combustion is the next generation oxy-fuel combustion technology combined the advantages of MILD combustion and conventional oxy-fuel combustion. It features as increasing the furnace temperature uniformity, promoting the radiation heat transfer, and achieving near zero emissions for fossil fuels. An oxy-fuel MILD burner with central fuel jet and high momentum oxygen jets was simulated by Computational Fluid Dynamics (CFD) method, and a finite-rate/eddy-dissipation model (FR/EDM) with two-step irreversible propane and oxygen reaction was used as the combustion model. Different parameters of burner including the momentum ratio of the oxygen and fuel jets and the distance between oxygen and fuel jets were simulated to evaluate the influence of burner parameters on MILD oxy-fuel combustion characteristics such as flue gas velocity and temperature, species fields, internal flue gas recirculation ratio, and different turbulence and chemical timescales. Moreover, the oxidation mixture ratio and Damkohler number were used to character the chemical reaction zone structure and the microscopic characteristics of MILD oxy-fuel combustion. Finally the optimized burner parameters were preferable to guide the design and operation for MILD oxy-fuel combustion.

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A fluid-structure interaction (FSI) analysis model for air heat exchanger was established based on computational fluid dynamics (CFD) by multi-physical field coupling method. The flow field analysis, FSI analysis and the stress field analysis of tube bundle were applied to the tube bundle by ANSYS. The three-dimensional finite element model was constructed and imported into the FLUENT module. The flow field simulation adopted the Reynolds averaged N-S equations, Realizable κ-ε turbulence model and the enhanced wall treatment method. The flow field pressure distribution was calculated and transferred from FLUENT module to Mechanical module through the coupling walls. The numerical analysis results showed that the maximum stress occurs in the joint of tube bundle and tube plate. Because of the structure discontinuity and the deformation coordination, the local stress concentration unavoidable. The flow field pressure in high speed and thermal deformation caused local stress concentration between tubes and baffles. The thermal stress distribution had a great influence on the total stress distribution of the heat exchange tube bundle.

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Harbin boiler company (HBC) started the development of technologies for high-efficiency ultra-supercritical boilers in 2012 using its technologies and extensive operation experiences of many ultra-supercritical boilers. These technologies were applied to efficiently reduce the CO_2 emission and operating cost of thermal power plants. In 2014, Huaneng Changxing 660MW high-efficiency ultra-supercritical boiler started operation, its unit efficiency was 46.035%, net coal consumption rate was 〜275g/kwh. Both values exceeded other standard ultra-supercritical boilers. As the boiler supplier, HBC is fully responsible for the boiler general performance design, manufacturing and commissioning supervision. This article presents the general conditions, design features and reliability run operating data with high-efficiency ultra-supercritical parameters of this project.

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This study investigates the use of the p-toluene sulphonic acid as a catalyst and a microwave heating system for synthesizing gallic acid esters from gallic acid and alcohols, including MT, EG, PG, iPG, BG, iBG and tBG. The gallic acid esters were analyzed using FTIR. The antioxidant effects in the biodiesel and the raw oils are studied with 1000ppm dosages. It was demonstrated that addition of the prepared compounds increased biodiesel oxidation stability. With the increase of the iPG and iBG antioxidant concentrations, the induction period of the biodiesel increased as well. When 250ppm of iPG and 600ppm of iBG were added, the oxidation stability of biodiesel met Chinese national standards and European standards of biodiesel stability. In comparison to commercially available antioxidants, the synthesized compounds demonstrated superior antioxidant effect.

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This paper reports the properties of nickel based alloy 617B and 740H used for superheater header for 700℃ USC boilers. The strength of the superheater header made of P91, P92, P122, VM 12 SHC, 9Cr-3w-3Co, HR6W, 617B and 740H piping with different diameters under different temperatures are calculated according to ASME Boiler and Pressure Vessel Code. This paper also analyses the suitable service temperature range of 700℃ superheater header manufactured by P91, P92, P122, VM 12 SHC, 9Cr-3w-3Co, HR6W, 617B and 740H piping, and puts forward some suggestions on 700℃ superheater header material selection. In the condition that the header metal design temperature is higher than 630℃, 617B should be selected to manufacture the header as the thickness less than 80mm, and 740H should be selected to manufacture the header as the thickness more than 80mm.

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Surface tension driven flows caused by the bidirectional temperature gradients have an important influence in the quality of crystal. In order to understand the characteristics of fluid flow and heat transfer in Czochralski configuration with bidirectional temperature gradients, a series of three-dimensional numerical simulations of the Marangoni-thermocapillary flow of silicon melt were conducted by using the finite-volume method. The temperature gradients are respectively produced by the temperature difference ΔT on the free surface and the constant heat flux q on the bottom of the crucible. Different flow patterns and temperature profiles are found when changing heat flux q at different ΔT. The flow is steady when heat flux q is small and it becomes oscillatory flow when heat flux q exceeds a critical value. The critical conditions and the characteristics of the flows were discussed. Besides, the results show that the increasing heat flux q makes a greater impact on the elevation of the melt temperature, while ΔT makes a greater impact on the instability of the melt. The location of the maximum melt temperature is determined.

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The paper introduces an outlier detection method based on MLS (moving least squares) and healthy sample model for hydropower unit. It uses the unit's monitoring data normal state to build base value and limit value of healthy sample model, and make condition partitions by dividing the scale of active power and water head into several sections. Then, MLS fitting method is used to fit the three-dimension surface of healthy sample model in the grid of unit operating conditions. It is proved by the analysis and experiment that the application of MLS fitting method can implement the dynamic threshold comparison and outlier detection in full condition for hydropower, comparing with the traditional LS (least squares) method, it is more reasonable and accurate for evaluating the healthy state of unit.

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The introduction of renewable energy in Japan is accelerating. In the report of the Long-term Prospect of Energy Demand and Supply (July 2015), the Japanese Agency for Natural Resources and Energy has made up, the desired percentage of renewable energy against total power supply is estimated as 22 to 24%, approximately double the 2013 performance figure of 10.7%. IHI Corporation is one of the Heavy Industry companies in Japan and is actively engaged in research and development relating to various kinds of renewable energy. Some of the activities that we are currently working on will be presented. Ocean current turbine power generation systems aim to extract the energy from the Japanese ocean current known as 'Kuroshio', a stable current located in the North Pacific region. The Twin IHI Gasifier (TIGAR[○!R]) is a circulating fluidized bed-type gasifier that can be operated under lower temperature and pressure conditions than other gasifiers. Biomass resources can be gasified by TIGAR[○!R] and used as the fuel for cogeneration systems and as the resource for hydrogen production systems. The power generation systems which use Organic Rankine Cycle (ORC) technology can recover energy from the low temperature heat source of industrial waste and also renewable energy such as geothermal, solar and biomass. 100 kW class ORC power generation systems operating at temperatures between 80 and 125℃ have been developed and tested using waste heat sources from diesel engines. Furthermore, IHI is also working on the development of biofuels using algae with the goal of practical use in the near future.

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Chinese energy is reliant on coal combustion, especially for power generation. But there are several challenges presented by this reliance, such as the significant air pollution in the northern and eastern regions or the shortage of good quality coals. The usage of low quality coals like high moisture lignite and high alkaline coals become more and more important. Due to the frequency emerging of haze condition from Beijing to Shanghai, the usage of coal become repugnant. However, there is not so much natural gas and oil reserved inside China. Therefore, the clean coal and ultra-low emission control especially multi-pollutant emission control become more and more important. In this plenary invited talk, the condition and challenge of coal combustion in China will be discussed. The upgrade of high moisture lignite from Inner Mongolia and Yunnan will be introduced. The alkaline releasing result from Xinjiang Zhundong coal during combustion process with LIBS (laser induced breakdown) on line measurement will be discussed. At last, the technology with pre-oxidization for simultaneous removal of SO_2, Hg and NO_x will be introduced, which has been used in the industry for ultra clean emission control.

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The cumulative global capacity of organic Rankine cycle (ORC) power systems for the conversion of renewable and waste thermal energy is undergoing a rapid growth, and is estimated to be approx. 2,000 MW_e considering only installations that went into operation after 1995. The potential for the conversion into electricity of the thermal power coming from liquid-dominated geothermal reservoirs, waste heat from primary engines or industrial processes, biomass combustion, and concentrated solar radiation is arguably enormous. ORC technology is possibly the most flexible in terms of capacity and temperature level, and is currently often the only applicable technology for the conversion of external thermal energy sources. In addition, ORC power systems are suitable for the cogeneration of heating and/or cooling, another advantage in the framework of distributed power generation. Related research and development is therefore very lively. These considerations motivated the effort documented in this article, aimed at providing consistent information about the state, and future of this power conversion technology. Firstly, basic theoretical elements on the thermodynamic cycle, working fluid, and design aspects are illustrated, together with an evaluation of the advantages and disadvantages in comparison to competing technologies. Then, a compendium of the many aspects of the state of the art is illustrated: the solutions currently adopted in commercial plants and the main-stream applications, including information about exemplary installations. A classification and terminology for ORC power plants are proposed. An outlook on the many research and development activities is provided, whereby information on new high-impact applications, such as automotive heat recovery is included. Possible directions of future developments are highlighted, ranging from efforts targeting volume-produced stationary and mobile mini-ORC systems with a power output of few kW_e, up to large MW_e base-load ORC plants.

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