bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on the Technology Co-Carbonization for Biomass and Coal
Authors: Zhu Gui Qin , Wu Wen Rong , Yang Xiao Min , Tang Qing Jie
Published: August 2013

This template explains and demonstrates how to prepare your camera-ready paper for Trans Tech Publications. Iodine adsorption method is used as a valuation means, the study was carried out on the co-carbonization of coal and biomass by the analysis of Iodine adsorption value. The research results show that the straw and cow dung has important effects on carbonization process; According to change rule of the Ignition loss rate and the iodine adsorption value, the iodine adsorption value of straw-coal co-carbonization product is higher than cow dung; Dashing treatment has significant effects on the iodine adsorption value carbonized product; the catalytic carbonization Biomass is the result of KOH effecting.
Synthesis of Double Crosslinked Amphoteric Cassava Starch Resin and Performance of Absorbing Cu (II)
Authors: Li He Ping , Hu Yang , Lv Hu Qiang , Yang Yong Zhe , Zhang Yao
Published: August 2013

Sodium polyphosphate-crosslinked starch was synthesized by using cassava starch and sodium polyphosphate as main material and crosslinked agent individually. On above basis, double crosslinked amphoteric cassava starch resin was synthesized by N,N'-methylene bisacrylamide as inner-crosslinked agent, dimethyl diallyl ammonium chloride (DMDAAC) and acrylic acid as amphoteric grafted monomer. The product was characterized by infrared spectrum (FTIR). The results indicate that the cassava starch was modified successfully, and the final product was double crosslinked amphoteric cassava starch resin. Adsorption behavior of Cu2+ was studied in the condition of different adsorption time, and found that the removal rate and the adsorption capacity of Cu2+ reached up to 98.3% and 196.6 mg/g respectively.
A Novel Extraction Method for Active Compounds from Traditional Chinese Medicinal Materials Environment Friendly
Authors: Liu Qing Shan , Yi Li Na , Li Ke Qin , Yin Xiao Ying
Published: August 2013

A novel extraction method based on environmental protection was founded through molecularly imprinted polymers (MIPs), overcoming the defects of traditional extraction methods, such as reagents consuming, complex operation and environmental pollution. MIPs were prepared by precipitation polymerization with picroside II or ginsenoside rg1 as the template molecule. The morphology of MIPs was characterized by scanning electron microscope and its static adsorption capacity was measured by the Scatchard equation. In addition, MIPs were filled in the solid phase extraction (SPE) column to separate and enrich the template molecule and its analogues, compared with C18-SPE column. The results indicated that MIPs have high affinity toward the template molecules, which might offer a novel method for the extraction of active compounds in the traditional herbal medicine.
Adsorptive Removal of Methylene Blue in Aqueous Solution with Alkali Activated Fly Ash
Authors: Zhu Shou Cheng , Miao Chun Guang , Wu Yan , Yang Hong Xing
Published: August 2013

Dyeing and finishing processes applied in the textile industry are the most common source of water pollution. The wastewater containing dyes is difficult to treat. The fly ash modified by alkali was investigated in this study to evaluate the removal efficiency of methylene blue in aqueous solution. The experimental results shown that the efficiency of adsorption could be prominent improved by alkali activated fly ash. Alkali activated fly ash could be an economical adsorbents used for printing and dyeing wastewater treatment processes.
Solid Phase Extraction of Trace Cobalt(II) from Aqueous Solutions through Physicochemical Adsorption by Surface Ion-Imprinted Polymer
Authors: Pang Ming , Wang Hong Mei , Hu Wen Lin , Li Li
Published: August 2013

A novel surface ion-imprinted polymer (S-IIP) has been synthesized by surface ion-imprinting concept in the presence of sodium trititanate whisker, Sr(II), chitosan and γ-Glycidoxypropyl trimethoxysilane (KH-560) for selective solid-phase extraction (SPE) of trace Co(II) from aqueous solutions. Characterizations of S-IIP were achieved by FT-IR spectra, SEM and surface area measurement. Results showed that the adsorption of cobalt(II) onto S-IIP follows pseudo-second order kinetics and could be fitted by the Langmuir isotherm with the maximum adsorption capacity Q being 8.27 mg×g-1 at 25°C. Thermodynamic parameters including DHº, DGº andDSº were calculated and it is indicated that Co(II) adsorption on S-IIP is exothermic, spontaneous and physical adsorption reaction. Moreover, according to the dimensionless separation factor RL (RL<1) it indicates that it’s a highly favourable adsorption. Finally, the detection limit (3s) of 5.6 ng·mL-1with the relative standard deviation (RSD) for 1.0 μg×mL-1 cobalt(II) of 1.86% (n=10) were obtained.
Synthesis of Biodegradable Hydroxy-Functionalized Poly(oligo(ethylene Oxide) Monomethyl Ether Methacrylate) (HO-POEOMA) Polymer by Inverse Miniemulsion ATRP
Authors: Zheng Lin Ping , You Qian Qian , Zhang Pu Yu
Published: August 2013

The biodegradable hydroxy-functionalized poly(oligo(ethylene oxide) monomethyl ether methacrylate) (HO-POEOMA) polymer is synthesized by inverse miniemulsion atom transfer radical polymerization (ATRP). The chain structure and component of such polymer is characterized by spectroscopic studies (1HNMR, IR and GPC).
Molecular Dynamics Simulation for Diffusion of Ribavirin in Water
Authors: Ji Ying Xue , Wang Feng He , Zhang Fan , Gong Xue Dong
Published: August 2013

Using molecular dynamics simulation (MDS) technology, the study simulates the diffusion of Ribavirin in water solution under different concentrations, and the diffusion coefficients have been calculated from the slopes of mean square displacement (MSD)-t curves. Both the normal diffusion time and the diffusion coefficient increased with increasing concentration of Ribavirin. It was found that the strong interactions were formed between the O1(Ribavirin) and H(H2O) pairs, and the higher the concentration of Ribavirin was, the stronger the interactions would be. Only the system of 10 Ribavirin /556 H2O appeared hydrogen bonds between O2(Ribavirin) and H (H2O) pairs, and O3(Ribavirin)-H (H2O) of all systems appeared the Coulomb and Van der Waals interaction. The interaction of O(H2O) and O(H2O) pairs were mainly caused by the short range repulsion.
Discussion on Comprehensive Control of Mine Heat Hazard
Authors: Zhang Ming Guang , Zhang Xi Jun , Zhang Yang
Published: August 2013

As the increase of mining depth and the improvement of mechanization, the thermal environment of mine have become worse and worse, its high temperature problem becomes increasingly serious. This phenomenon severely endangered the safety of mine production and miner's physical and mental health. Mechanical refrigeration method has replaced traditional non artificial cooling method, which has become the main measure of preventing and controlling mine heat hazard. This paper has disgussed measures of preventing and controlling of mine heat hazard, analyzing and comparing advantages and disadvantages of four kinds of mine air conditioning system, then point out that comprehensive, efficient and energy saving are the development direction of preventing and controlling mine heat harzard.
Numerical Simulation of Gas Leakage and Diffusion Based on FLUENT
Authors: Fu Lin Zhi , Li Yu Feng , Li Gang
Published: August 2013

A two-dimensional unsteady flow model was established by Realizable k-ε turbulence model and SIMPLE algorithm, which was applied to conduct numerical simulation of sudden leakage and diffusion of coal gas in the plant area. Then, time-dependent distribution laws of coal gas under different influencing factors were analyzed. The results showed that as the leaking mouth diameter, internal pressure and wind speed increase, the concentration was roughly the same near the mouth; coal gas that was 3m away from the mouth diffuses more quickly and the area covered within explosion limit of coal gas expanded to some extent. For different gas medium, converter gas spread more widely than coke oven gas. The former accumulated on the ground, the latter accumulated above the ground.
The Basic Study of Plant Esterase in Pesticide Residue Examination
Authors: Chen Jing , Zhang Yao Li , Wu Yue , Zhang Jiong
Published: August 2013

We choose three plant esterase sources, through the measurement of enzyme activity , the plant esterase that sieved efficiently withdraws the raw material, and as to it's the crude extract of the esterase to suggest the reaction condition of the liquid to carry on the system excellent turn, such as pH, reaction time and dilution. So we can guarantee the enzyme inhibition represses the method in great quantities takes out to check the sample carries on the quickly thick of accurate degree, also soon measures the card for the fixed and organ phosphorus pesticide of thorough study to provide the reference.
Partitioning of Harmful Elements in PM10 from Air-and Oxy-Coal Combustion: Iron and Sulfur
Authors: Wu Jian Qun , Yu Dun Xi , He Lan Lan , Chen Jun , Si Meng Ting , Lv Wei Zhi , Xu Ming Hou
Published: August 2013

Adverse health effects of Fe and S in airborne particulate matter (PM) have been reported. However, little work has been done to characterize Fe and S in PM10 from coal combustion. In this study, a sub-bituminous coal (coal A) and a bituminous coal (coal B) were subjected to combustion in a drop tube furnace under air-and oxy-firing conditions. Size distribution and elemental composition of PM10 (PM with aerodynamic diameter 10 μm) were obtained by low pressure impactor and X-ray fluorescence techniques, respectively. The partitioning characteristics of Fe and S in PM10 were investigated. Data shows that particles of ~0.1μm contains the highest concentration of Fe for both coals under different combustion conditions. The concentration of Fe in the ultrafine particle mode decreases when switching from air combustion to oxy-fuel combustion with 21% O2. It increases when the oxygen concentration increases from 21% to 32% O2 during oxy-fuel combustion. Changing combustion conditions has little effects on Fe partitioning in particles >0.3μm. The concentration of S in PM10 increases with decreasing particle size, but changing combustion conditions have inconclusive influence. Fe and S are dominant elements in ultrafine particles, indicating a greater threat to human health.
Design and Full-Scale Test for Cup-Type Steel Tubular Tower of UHV Transmission Line in Heavy Icing Area
Authors: Zhang Zi Fu , Yang Jing Bo , Yang Feng Li , Li Qing Hua
Published: August 2013

The ZB1 cup-type steel tubular tower is the first single-circuit tower for UHV transmission line in heavy icing area. Except the ground supports, steel tubular are applied in whole tower. The plug-in boards and forging flanges are used in ZB1 tower,and the highest strength of tubular steel is Q345. Through the monographic study on the tower optimizationnode structuretowers Eiffel effect and bending moment at member end et., The design of ZB1 cup-type steel tubular tower is improved. The success of full-scale test verified the reliability in design and manufacture of cup-type steel tubular tower for UHV in heavy icing area. Research results of this paper can be applied in UHV transmission line projects.
Seismic Performance Analysis of Tower Lines System under Multiple Support Excitation
Authors: Sun Jian Mei , Li Jun Qiang , Yang Fu Gang
Published: August 2013

In order to determine the calculational model of long span transmission tower structure under the multiple support excitation, tower-lines system are adopted. Seismic Performance of long span transmission tower lines system under Multiple Support Excitation were studied by time history analysis method. The seismic response difference of two kinds of excitation is analyzed from Dynamic Characteristics and the number of dangerous bar. It will offer the theory data for the seismic design of the kind of structure. Through analysis, the seismic response difference of the two kinds excitation is correlative to the apparent velocity; Therefore long span transmission tower structure should be considered the effect of multiple support excitation, otherwise the conclusion will be inclined to conservative or risk. Key words: tower lines system; seismic response; time history analysis,multiple support excitation
Speed Control of Switched Reluctance Motors Drive System Based on Fuzzy Control
Authors: Li Jun Wei , Zhang Zhen Dong , Ni Yuan Yuan
Published: August 2013

The switch reluctance motor (SRM) speed control system is often difficult to control due to its nonlinearities and parameter variations. In this paper, a fuzzy logic control (FLC) system has been presented to speed control of the SRM. The control system is composed of speed controller and current controller. The main task of the speed controller is to provide the appropriate control signal to the current controller based on the difference between the desired speed and the actual speed of the motor. In the speed control part, the fuzzy controller is used to reject the unknown and uncertain parameters in the SRM and in the load torque. The current controller evaluates the difference between the actual and the desired phase current and implements hysteresis current control. Simulation results demonstrate the effectiveness of the proposed control strategy under different operating conditions of the SRM.
Automatic Measurement of Stator Resistance for Permanent Magnet Synchronous Motors Based on Simple Linear Regression Model
Authors: Li Feng , Xia Chao Ying
Published: August 2013

In the field-oriented vector control system of permanent magnet synchronous motor (PMSM), the performance is directly dependent on the accuracy of motor parameters. Because of nonlinear factors of the inverter, the difficulty in accurate compensation of voltage error and low accuracy of measurement are problems which exist in stator resistance identification approach based on traditional DC voltmeter-ammeter method. In this paper, the ordinary least squares method based on simple linear regression model is used to finish the automatic measurement of stator resistance. It is verified that the method has higher measurement accuracy according to the experimental result. Furthermore, nonlinear factors of the inverter are not needed to be taken into account using the method, which has comparatively strong practicality in engineering.
Calculation and Analysis of Geo-Magnetically Induced Current in Earth Based on Plane Wave Method
Authors: Wang Xiao , Liu Lian Guang , Liu Chun Ming
Published: August 2013

Geo-magnetically Induced Current (GIC) is not only flowing in conductors such as power grid and pipeline, but also flowing in earth and GIC in earth will affect GIC in conductors. Thus studying the relationship between GIC in earth and earth conductivity is significant to understand the impacts of conductivity on GIC in earth and conductors. This paper uses Maxwell equations and plane wave method to analyze GIC density lever and distribution characteristics in different earth depth of uniform/layered earth conductivity model and gives the relationship between conductivity and GIC in earth. The results indicate that, the smaller the earth conductivity, the deeper earth GIC distributes, and earth conductivity structure has great impact on GIC. At last, this paper proposes that to calculate GIC in power grid accurately, we need to establish more accurate earth conductivity models.
Research on Parameters Matching of Ultralight Electric Aircraft Propulsion System
Authors: Kang Gui Wen , Hu Yu , Li Ya Dong , Jiang Wen Hui
Published: August 2013

The propulsion system of ultralight electric aircraft is one of the general aviation technology development directions. It has the advantages such as light pollution, low noise, high energy utilization ratio, simple structure, easy maintenance, high reliability, less heat radiation, little operation cost and so on. Combined with the certain type of ultralight aircraft design parameters, the layout of aircraft electric propulsion, the principles and steps of the parameter matching of electric propulsion system were presented. The method of parameter matching and performance verification of electric propulsion system was put forward. The feasibility of the system is verified from the point of dynamic property. The study of parameter matching of electric propulsion system could not only provide basis for the integrated optimization for electric power system, but also evaluate the performance of the system simulation as reference.
An ANFIS Solution for Real-Time Control of the EGR & VGT in a Diesel Engine
Authors: Peng Zhi Jun , Cheng Li , Wang Wei Ji , Gao Bo , Aitouche Abdel
Published: August 2013

An ANFIS (Adaptive neuro-fuzzy inference system) controller which bases on Takagi-Sugenos method and combines the advantages of neural controller and fuzzy multi-variable controller has been studied and developed for the real-time control of EGR and VGT in a diesel engine. In the AVL-BOOST and Matlab/Simulink co-simulation environment, the control performance of ANFIS controller has been compared with those optimal control strategies based on a fuzzy logic controller. Results show the new controller can have more active control to EGR position and the optimal emission levels can be maintained.
A Method for Improving Compensation Performance of the Active Power Filter
Authors: Deng Wei Si , Zhang Bu Han , Ding Hong Fa , Shao Jian , Jin Bing Jie
Published: August 2013

Distributed renewable energy connected to the power grid in the form of micro-grid, which makes a great impact on the power quality of the grid. Active Power Filter (APF) is a kind of effective device, which can improve the power supply quality and purify the power pollution. It‘s particularly significant to improve the APF’s performance. Based on the selective harmonic current control strategy, which is used to solve the problem, that the main times of the harmonic current is not sufficiently compensated, this paper considers to adopt the LCL filter on the grid-side to further improve the compensation performance of active power filter. This improvement can reduce the high frequency harmonics caused by the way of PWM high frequency modulation. Finally a case study simulated by PSIM software verifies the superiority of the proposed measure.
Dynamic Response Improvement of the DPC-SVM Three-Phase Grid-Connected Inverter
Authors: Yao Zhi Lei , Xiao Lan , Xu Jing
Published: August 2013

As the dynamic response of the traditional direct power control using space vector modulation (DPC-SVM) is slow, an improved DPC-SVM for the three-phase grid-connected inverter is proposed. The feed-forward reference powers are used to improve the dynamic response. The operating principles of the traditional and improved DPC-SVMs are illustrated. Experimental results of a 15-kVA three-phase grid-connected inverter with the traditional and improved control methods verify the theoretical analysis.
Investigation of Gate Degradation Characteristics of AlGaN/GaN HEMTs under PWM Stress
Authors: Chen Chen , Xie Gang , Tang Ceng , Sheng Kuang
Published: August 2013

An investigation of gate degradation characteristics of AlGaN/GaN HEMTs under PWM stress is proposed in this paper. The device under testing features double source-connected field plates to reshape the surface electric field. A PWM signal with the operation frequency varied from 10 kHz to 1 MHz was applied to the gate electrode while the source was shorted to ground. HP 4155B was used to measure the gate characteristic of the device by every 30 minutes. The value of on-resistance shows an increase of 12.9 % after the device has been under stress for 30 minutes with the switching frequency of 10 kHz and the degradation is improved with higher switching frequency, while the threshold voltage and gate leakage current do not change significantly during the test.
Studies from Establishment of a Chinese Provincial Microgrid Standard
Authors: Zhao Min , Huang Shao Wei , Wu Xiang Yu , Huang Xiu Qiong , Xu Qin Biao
Published: August 2013

A standard is of great importance to microgrid application and development. So far, there is no published standard specifically for microgrids in China except for the Guangxi provincial standard, which is drafted by the authors. This paper focuses on the lessons that the drafters have learned from the standard establishment. The background of making such a standard is introduced first, and its purposes are clarified, as well as the difficulties in standard drafting. Then the structure of this standard is explained, and one technical specification is detailed as an example. Further studies on planning and design of microgrids, multi-microgrids integration and limitations of this standard are discussed. This work can provide reference for establishing a national microgrid standard, thus can stimulate the standardization of microgrids in China and promote their application.
Study on Integrated Resource Strategic Planning for Power Industry
Authors: Zhao Zhi , Yuan Jia Hai , Huang Wen Jie
Published: August 2013

Integrated Resource Strategic Planning (IRSP) is an extension of Integrated Resource Planning (IRP) at the national level for power planning. It provides a new theoretical foundation for the implementation of demand-side management (DSM) in the deregulated conditions. In this paper, IRSP model for power planning is proposed. In the model, both supply-side and demand-side resources as efficient power plant (EPP) are considered in the optimization process. A case study for the power planning in the United States is presented in the paper. The results indicate that, comparing with traditional planning the IRSP model can not only achieve the minimum total costs, but also reduce the supply-side capacity installation and the related pollution emissions.
Operation Characteristic of a Mechanical Vapor Recompression Heat Pump Driven by a Centrifugal Fan
Authors: Pang Wei Ke , Yang Lu Wei , Zhang Zhen Tao
Published: August 2013

A mechanical vapor recompression heat pump driven by a centrifugal fan is designed together with falling-film evaporation. Based on theoretical analysis, experimental research is applied to study the fan type of MVR. Choosing water as the experimental medium, the operation characteristic of MVR applied to low evaporation is examined. Practically, the pressure difference of the unit is likely to keep stable while its evaporation pressure goes up. After the system performance is tested and analyzed, it shows that the total evaporation water and total input energy increase as its evaporation pressure grows. Further, some calculation is done and the result indicates that its SMER and COP decrease while the evaporation pressure rises. The reason of this phenomenon is: the leakage loss of the fan inside goes up and its displacement efficiency reduces as the evaporation temperature and pressure is high; finally, it brings forth the drop of the systems adiabatic efficiency. Finally, the trend of average input work for compressed vapor is compared in three different terms. The trend of average input work by calculation is the same as that in theory; that is to say, both of them descend when the evaporation pressure ascends. Because of displacement efficiency, the trend of average input work by measure is different from that in theory; that is to say, the average input work by measure grows slightly when the evaporation pressure goes up.
The Research of the Exergy Transfer Characteristic in the Process of Steady Heat Conduction during Constant-Section Straight Ribs
Authors: Wei Bo , He Wei , Fan Xiao Chao
Published: August 2013

The ribs have been used to raise the area of convection heat transfer and consume little material simultaneously. This article adopt the analyze method of exergy transfer, with the help of gained temperature distribution in the constant-section straight ribs, derived the equation of the exergy distribution and the coefficient of exergy transfer distribution, with pay more attention to the rules of the energy quality decaying during the process of heat transfer in ribs. The solving results have been acquired in the Aluminium ribs and steel ribs with the case of same geometric parameter and same temperature parameter. The results show that the temperature, exergy value and the coefficient of exergy transfer is descending along the length direction of ribs. The parameter of Aluminium ribs is greater than the steel ribs because of the different property.
A New Modified SVD Method Applied in 3D Acoustic Temperature Field Reconstruction
Authors: Yang Wei , Zhu Xiao Liang
Published: August 2013

In order to solve the ill-posed problem in 3D acoustic temperature field reconstruction, the paper proposed a new modified singular value decomposition (SVD) method.According to their reliability ,singular values were divided into three parts and got various degree of modification respectively. To verify the performance of the new algorithm based on the modified SVD method,two model temperature fields were reconstructed when the signal-to-noise ratio (SNR) of sound flight-time data was 50dB , 40dB and 30dB respectively.And the results were compared with those based on routine Truncated singular value decomposition (TSVD) and Tikhonov methods. Simulation results show that the new algorithm has higher precision, better anti-noise ability than the routine methods and it is more suitable for the complex temperature fields reconstruction, thus it is expected to be used for temperature field reconstruction on-line.
Numerical Study of Selective Non-Catalytic Reduction Process in Large Utility Boiler
Authors: Cao Qing Xi , Liu Hui , Wu Shao Hua , Wu Wen Yan , Yu Sui Ying , Li Zhen Zhong , Yang Chun Hui
Published: August 2013

To provide a theoretical guidance for the application of selective non-catalytic reduction (SNCR) in a large capacity utility boiler, numerical study of SNCR process in a 600 MW utility boiler was performed based on computational fluid dynamics (CFD) code Fluent. Good agreement of the calculation results with the industrial test data confirms the reliability of the calculation model. It is found that the NO removal efficiency is low and NH3-slip is high, because the injected reducing agent could not mix with the flue gas adequately, and the furnace temperature is not uniform in utility boiler with large furnace size. Aiming at this problem, the commissioning scheme for reducing agent injection system was optimized, and CO was added together with the reducing agent. As a result, NO removal efficiency increases from 19% to 27%, and NH3-slip decreases from 59 ppm to 13 ppm.
Development of Simulation Model for Series Hybrid Electric Crawler Bulldozer (SHECB) Based on ADVISOR
Authors: Zhang Bao Di , Zhang Xin , Zhang Xin , Xi Li He
Published: August 2013

With the expansion of the hybrid electric technology, hybrid electric driving system is introduced from hybrid electric vehicle into construction machinery such as bulldozer. Therefore, the corresponding simulation models of hybrid electric bulldozers need to be developed firstly for further study of the new application. In this paper, through analyzing on the characteristics of crawler bulldozers, a whole vehicle module and a crawler module are created, then the relevant configuration files are modified, and finally the simulation model of series hybrid electric crawler bulldozer (SHECB) is built based on ADvanced VehIcle SimulatOR (ADVISOR).After loading an operational driving cycle of the bulldozer, a certain type of hybrid bulldozer being developed is simulated. The results show that the simulation model developed can simulate the performance of the SHECB favorably.
The Model of a Free Piston System Based Organic Rankine Cycle and the Analysis of Sensitive Factors
Authors: Han Yong Qiang , Zeng Jiao , Qiao Chuan
Published: August 2013

For recycling complementary energy efficiently, WMs latent heat of vaporization is made full use of in a free piston based organic rankine cycle exhaust gas energy recovery (ORC-FP) system. In this paper, the model of ORC-FP system has been established by the software GT-suite 7.0. Three sensitive factors (WMs gas ratio, piston damping coefficient and power WMs pressure) will be discussed by simulation results. The conclusions are shown as follows: Firstly, when WM state is 450K, 1.1MPa (Power WM) and 320K, 1.1MPa (Cooling WM) at inlet, the systems single cycle efficiency is highest about 69.21%, and the lowest is about 42.32%. Certain fluctuation of single cycle (SC) efficiency exists between two adjacent cycle, and the highest difference can reach 26.89%. Secondly, the systems total cycle (TC) efficiency decreases along with the increasing of damping coefficient (piston load). At the minimum piston damping coefficient (about 7500 N-s/m), the systems highest total cycle efficiency is 46.53%, and at the maximum (about 8750 N - s/m), the lowest total cycle efficiency is 35.66%. Thirdly, when damping coefficient is 7500 N-s/m, the higher pressure of WM is, the higher the systems total cycle efficiency is. In the pressure of 1.1MPa, the system reaches the highest efficiency which is about 46.53%, and in the pressure of 0.9 MPa reaches the lowest which is about 26.74%.
Numerical Study of Dynamic Behavior of Joule-Heated Pool
Authors: Zhang Ming Jie , Zhang Xiao Hui , Chen Lin Jing
Published: August 2013

In the present numerical study, we consider a low-Prandtl liquid metal heated by Joule effect in a rectangular cavity with an aspect ratio of 2. The direct current provides heat to the process medium by a pair of plate electrodes, located at the cavity sidewalls. The simulations have been carried out using finite volume method for fixed values of the Prandtl number, Pr=0.01, and of the Rayleigh number, Ra=1.5×104, while the Hartmann number, Ha=1410, Comparison between the original noise-free data and cleaned data is explored. More precisely, accurate performances predicted using removing noise from numerical simulation data is obtained to define the inherently complicated nature of the competition of buoyancy with electromagnetic body forces.
Numerical Simulation of the Effects of Baffle on Flow Field in a Stirred Tank
Authors: Hao Zong Rui , Xu Juan , Bie Hai Yan , Zhou Zhong Hai
Published: August 2013

Flow characteristics of stirred tanks with different structures were calculated by taking RNG k-ε model as the turbulent flow model. The results showed that at the same rotational speed, a large number of axial and radial vortexes were formed in the stirred tank with the baffle. The velocity in the blade area was high, and it decreased rapidly with the increasing distance to the blade. The double peak area of the radial velocity was formed in the stirred tank with baffle, and the high and low speed cycles were obtained in the cross-section. The baffle increased not only the axial circulation of the liquid in the tank but also the radial circulation, which help to mix the liquid.
CFD Simulation of Gas Residence Time Distribution in Agitated Tank
Authors: Li Liang Chao
Published: August 2013

Gas residence time is an important parameter for gas-liquid agitated tank. Two approaches, i.e., Euler-Tracer method and CFD-DPM method are proposed for predicting gas residence time distribution (RTD) in an aerated agitated tank by using a Fluent 6.2 software package. The simulation results show that the characteristic of the gas-RTD is a curve with single peak and long tailing. Bubble size, stirring speed and gas inlet flow rate have great effect on gas-RTD in the stirred tank. Small bubbles have wider residence time distribution and stay in the vessel longer than the large bubbles and tend to complete mixing. With increasing of impeller speed or decreasing of gas inlet rate, gas-RTD become wider and have longer average gas residence time, which is in favor of gas effectively utilization.
Numerical Investigation for Inner Flow Fields and Structure Improvements of Medium Speed Mill
Authors: Zhu Xian Ran , Liu Cheng Yong , Cheng Liang
Published: August 2013

The numerical model for ZGM95 medium speed mill is built and the inner flow fields are simulated by employing the commercial code of FLUENT. The results show that the distributions of the static pressure and the flow rate are not uniform for 36 nozzle rings due to the primary air entering the mill only from one side. Two modified structures are assumed to improve the mills performances and the corresponding models are simulated further. The flow fields are still not good enough and the pressure drop increases sharply in the mill when blocking several nozzle rings, and this structure is not recommended if the amount of pulverizer rejects is not extremely huge. The structure with double-inlet can improve the distribution of the flow fields effectively in the mill and few pressure drops of the mill increase. However, the feasibility of the double-inlet structure is also depends on the field conditions. The pressure drop will be less and the flow fields will be better when adopting the horizontal inlet duct instead of the inclined one.
Rife-Vincent (I) Window Interpolated FFT Algorithm Based on Cubic Spline Function
Authors: An Li Li , Zhu Rong , Yang Yao Min , Xu Min , Chen Fei
Published: August 2013

In order to further improve the precision of harmonics measurement, the paper provides a new interpolation fast Fourier transform (FFT) algorithm based on RifeVincent (I) window. By using the cubic spline function to approach the ninth multinomial of frequency modification coefficient and the function of harmonic amplitude correction of the interpolation FFT algorithm based on RifeVincent (I) window, the computing speed has been improved. It can solve the contradiction between calculation accuracy and computational speed of windowed and interpolated FFT algorithm. The simulative results show that RifeVincent (I) window interpolation algorithm by using cubic spline function has the amplitude error less than 0.00001 %, the frequency error less than 0.000001 Hz, and the phase error less than 0.01%.
CFBB Bed Temperature Control Strategy Based on Improved DMC
Authors: Liu Chang Liang , Li Fei Fei
Published: August 2013

Whether the bed temperature of circulating fluidized bed boiler (CFBB) is stable or not affects the efficiency of the entire unit. According to the characteristics of an uncertain system with large delay, large inertia and time-varying of the bed temperature system, this paper proposed an adaptive dynamic matrix control (DMC) algorithm based on the real-time error correction. The algorithm can make the dynamic matrix controller more accurately, more flexibly and more applicably on reflecting system changes by revising the errors during the feedback regulating. The simulation results show that the control algorithm is of good adaptability and robustness and satisfactory control effect in the bed temperature system can be achieved.
An Integral Method for Solving the Point Reactor Neutron Kinetics Equations with Newtonian Temperature Feedback
Authors: Fan Gen , Liu Wen Bin
Published: August 2013

A numerical integral method to efficiently solve the point kinetics equations with Newtonian temperature feedback is described and investigated, which employs the better basis function (BBF) for the approximation of the neutron density in integral of one time step. The numerical evaluation is performed by the developed BBF code. The code can solve the general non-linear kinetics problems with six groups of delayed neutron. For the application purposes, the developed code and the method are tested by using a variety of problems, including ramp reactivity input with or without temperature feedback. The results are shown that the BBF method is clearly an effective and accurate numerical method for solving the point kinetics equations with Newtonian temperature feedback, and it can be used in real time power reactor forecasting in order to prevent the reactivity accidents.
Research on the Transformer Condition Assessment Based on the Entropy Weight Method
Authors: Liang Hai Feng , Lin De Shan
Published: August 2013

As one of the important hinge equipments in the electric power system, the operating reliability of power transformer has deep influences on security and stability of power system. In order to guide transformer maintenance and assess the risk of the electric power system, it is of important significance to know the state of the running insulation of transformer in time and accurately. Based on the analysis of transformer state parameters, the method determining the evaluation index weight has been studied; methods of entropy value objective weight and improved analytic hierarchy process subjective weight have been combined to calculate the weighting coefficients of evaluation indexes. Its correctness has been verified by analyzing examples of transformer operation.
Analysis of a Transformer Time-Varying Outage Model for Operational Risk Assessment
Authors: Tian Ke , You Da Hai , Li Yi Long , Pan Kai , Wang Ke
Published: August 2013

Firstly, the operating mechanism in developing process of transformer internal latent fault and external accessory fault is analyzed. Then, dissolved gas analysis (DGA) outcome and average degree of polymerization (DP) are used as an indicator to classify transformers operating condition, the multi-state Markov process model based transformers operating condition is proposed to estimate the internal failure rate. According to the method of weather condition classification, the external accessory failure rate model is proposed by considering the influence of weather change. A time-varying transformer outage model for operational risk assessment is proposed by using the multi-state Markov process to estimate the time-varying failure probability. Finally, a numerical is presented.
Effect of Shielding Lines on Power Frequency Electric Field under Overhead Lines
Authors: Jiang Yu Ze , Liang Zhen Guang , Ma Wei Jie , Wang Hong Chuan
Published: August 2013

This paper discusses effect of shielding lines on reduction of electric field produced by overhead lines. Charge simulation method is used. Influences of height, space and number of shielding lines on electric field are calculated. Space between shielding lines has reverse roles on influencing area and maximal electric field. Number and space of shielding lines should be carefully selected to shielding a certain area. Analytical method is also used to express induced electric field by shielding lines. Result of comparison with charge simulation method shows that it is suitable for area outside of three phase lines.
Study on the Optimal Condition of a Copper-Bearing Gold Ore Cyanide Leaching Using Orthogonal Design
Authors: Wang Kai , Cui Yi Qi , Tong Xiong , Dong Peng , Meng Qi
Published: August 2013

The copper-bearing ore assays 1.7g/t Au, 50.43% Fe and 0.41% Cu. Recovered gold by cyanide leaching, in this study, the orthogonal test design was used to examine effects of NaCN dosage, leaching time, agitation intensity, particle size on gold leaching rate and determine the optimal operation combination for the purpose of increasing gold recovery. Gold extractions of 92.34% were achieved using a particle size of 90%-200 mesh, NaCN dosage of 1.8kg/t, leaching time of 36h and agitation rate of 400r/min.
Research on Characteristics of Ore-Forming Fluids of Dahongshan Copper Ore Deposit
Authors: Deng Ming Guo , Lv Chang Liang , Zeng Lei
Published: August 2013

This paper analyzes the fluid inclusions, micro-thermometry, the pressure, salinity and pH of ore-forming solution, and isotopes of H and O, C and O of the Dahongshan copper deposit in Yunnan Province. The result shows that these inclusions are dominated by liquids (LH2O), gases and liquids (LH2O+VH2O), and daughter mineral-bearing (LH2O+VH2O+SNaCl) three-phase ones and the liquid inclusion accounts for about 50%, and the liquid composition mainly include Na+,K+,F-,Cl-. Homogenization temperatures at the early stage vary from 290°C to 330°C, with the peak value around 350°C, while at the late stage the figures vary from 160°C to 250°C, with the peak value 250°C. The general salinity ranges from 16.0 wt% to 35.9wt%, and the maximum reaches 45wt%. The value of δ18OH2O and δD in the mineral inclusion ranges from-1.15% to 6.61% and from-58% to-78% respectively. These isotopic data imply that the ore-forming fluids were mainly derived from the magmatic water, the metamorphic water and the meteoric water.
A Non-Toxic Depressant for Galena in Differential Flotation of Cu-Pb Sulfides
Authors: Qiu Xian Hui
Published: August 2013

Tannic acid, a natural polymer extracts from trees, was found to selectively depress galena while chalcopyrite was floated by xanthate. Micro-flotation studies, adsorption and Fourier transform infrared spectroscopy have been employed to investigate the mechanism. Micro-flotation studies shown that tannic acid can effectively depress galena while depress chalcopyrite weakly in the entire pH range. The adsorption results shown that the tannic acid adsorbed on chalcopyrite and galena surface influenced by the pH value, the higher the pH, the less of adsorption density. Tannic acid adsorb on galena through complexation with the lead ions, not with hydroxyl complex in the galena surface. Fourier transform infrared spectroscopy revealed that tannic acid interacted with lead ions by the hydroxyl groups on the phenol group. Tannic acid may be replace the hazardous inorganic depressants such as cyanide, dichromate and sulfur dioxide used in differential Cu-Pb sulfide separation.
Containing Rare Earth Phosphate Rock Processing and Rare Earth Enrichment in those Processes
Authors: Nie Guanghua , Sun Ti Chang , Li Shuai , Li Hai Lan
Published: August 2013

The reserve of sedimentary phosphate deposits in Guizhou province in western China is huge, but has been no development because of its difficulties of comprehensive utilization. Using mineral processing techniques, Rare earth containing phosphate rock flotation and flotation concentrate leaching test study were done. Rare earth enrichment in those processes was studied too. Through rougher flotation conditions test, it was determined that the optimal rougher flotation conditions were grinding fineness 75% -0.074mm, H2SO4, H3PO4 and SOP dosage of 10kg/t, 0.15kg/t and 0.8 kg/t. A reverse flotation flowsheet consisted of one roughing, one cleaning and one scavenging stage was used for the closed-circuit flotation tests. Phosphate concentrate could be got with P2O5, MgO, REE grade of 31.87%, 0.98%, 0.15% and recovery of 85.83%, 8.84%, 86.81% respectively. P2O5 recoveries and REE recoveries of phosphate concentrate was a positive linear relationship. Under the condition of liquid/solid3:1, acid/ore ratio 1.2, leaching time 3.5 hours and temperature 75°C, the phosphate concentrate was leached by sulfuric acid. The better indicators that P2O5 leaching rate of 95.92% and REE leaching rate of 52.11% could got.
Experimental Study on the Cyanidation of a Low-Grade Gold with High Content of Arsenic in Myanmar
Authors: Yang Peng , Zhang Gui Fang , Yang Qing Rong
Published: August 2013

The content of gold ore in Wa region of Myanmar is 3.52 g/t ~5.87g/t, and it contains 9.32% arsenic, it belongs to awkward gold ore with gold embeds in pyrite as fine granular. so the drawbacks of low leaching rate and wasting of resources existed in the early cyanide production. A technology of adjusting pH in lime water and further leaching after regrinding was confirmed by contrasting the mixing effect in different reagent. The experiment results showed that a leaching rate of 81.63% has been obtained by adopting the conditions which pulp density is 40%, the pH of pulp adjusted in lime water is 10, the total NaCN dosage of three additions is 3 and the material is reground before third addition.
Flotation Behavior of Smelting Abandoned Copper Slags
Authors: Mu Xiao , Kang Duan , Chen Jian Hua
Published: August 2013

The flotation of smelting copper slags in Yunnan has been studied in this paper. The influences of grinding fineness, different kinds of collectors and the dosage of sodium sulfide, GZT, which influence the flotation results, are tested. The experimental results show that in the first stage of roughing, a good flotation result is obtained, the concentrate copper grade reaches 24.12% and the flotation recovery rate reaches 82.98%, when the grade of copper slags is about 2.1%, under the circumstances that the grinding fineness is 85.6%, the amount of Y-89 is 400g/t, the amount of sodium sulfide is 2500g/t, and the amount of GZT is 80g/t.
Influence of Collectors on Flotation of Fine Tin Middlings after Gravity Separation
Authors: Zhao Wen Juan , Li Ming Xiao , Jian Sheng , Zhang Chen Hu , Feng Li Ping
Published: August 2013

The study was aimed to recover tin minerals from fine tin middlings from Laos after gravity separation. The middlings had a tin grade of 0.5%, belonging to a refractory ore, so flotation was used to recover tin of them. Based on the research of influence of collector on flotation of fine tin middlings, an optimum index was obtained in the closed-circuit flotation. Finally, the concentrate with a tin grade of 3.45% and a tin recovery of 59.85% was obtained, which was concentrated by 6.9 times compared with the crude ore, which greatly improved the economic benefit for the concentrator and highly increases the efficiency of separation.
Photoinitiation Synthesis and Properties of Anionic Polyacrylamide
Authors: Zhang Lin Lin , Nie Rong Chun , Ma Shuai , Sun Yin Yu
Published: August 2013

Through the photoinitiation technology synthetizes anionic polyacrylamide (APAM), with the raw material of sodium acrylate (AANa) and acrylamide (AM). The results show that the best ratio of AANa-AM is 1:3, mass fraction of AM is 30%, pH value is 7.0, reaction temperature is 40°C, good intrinsic viscosity and solubility in APAM can be obtained.Meanwhile, IR characterization meets APAM characteristic groups using for application characterization of Qian ying zi slime water and the results show that the product can be seen from flocculation results of synthetic product on the coal slurry with the light transmission rate of 88.1%.
Study on Process Mineralogy and Titanium Separation of Ti-Bearing EAF Slag
Authors: Zhang Jun Hui , Li Cheng Xiu , Zeng Ling Xi
Published: August 2013

Panzhihua Steel Plant adopts a new process - "rotary hearth furnace (RHF) direct reduction - electric arc furnace (EAF) deep reduction" - to manufacture iron, and the resultant Ti-bearing slag contains 44.03% titanium dioxide and has higher contents of impurities such as calcium, magnesium and silicon, so it cannot be prepared titanium dioxide alone. In order to effectively utilize the slag, process mineralogical research and a large number of mineral processing tests have been conducted so as to ascertain the separability of Ti-bearing slag. The results show that flotation technology is an effective way to dispose the slag, comparing with other beneficiation methods. Finally, titanium concentrate indexes, TiO2 grade of 66.49% and recovery of 71.91%, were obtained by using open circuit flow of "2-roughing and 4-concentrate".
Study on the Recovery of Sulfur from Multi-Metals Tailings
Authors: Lv Xiang Wen , Tong Xiong , Xie Xian , Zhou Qing Hua , Zhou Yong Cheng , Ren Shuai Peng
Published: August 2013

A beneficiation experimental research is conducted on sulfur-containing 18.17% multi-metals tailings. On the basis of the traditional mineral processing technology, it introduces X-51, a new type sulfide mineral activator, to instead of copper sulfate. Eventually, the sulfur concentrate grade is 47.51% with the recovery of 92.11%. The effectively recovery of the sulfur is creating good economic benefits and environmental benefit.
Study on Dissolution Behavior of High Titanium Bauxite
Authors: Li Jun Qi , Zou Yong , Chen Chao Yi , Jia Yong Zhen
Published: August 2013

Dissolution behavior of high titanium bauxite was investigated. The effect of several factors on dissolution of alumina and titanium dioxide were examined. The experimental results showed that the titanium dioxide dissolution rate was 9.82% and alumina relative dissolution rate was 88.83% under the best dissolution conditions for dissolution temperature of 240°C, lime add volume of 4%, and alkali concentration of 220g/L.