scholarly journals Application of electrodynamic drum separator to electronic wastes separation

2016 ◽  
Vol 32 (1) ◽  
pp. 155-174 ◽  
Author(s):  
Antoni Cieśla ◽  
Wojciech Kraszewski ◽  
Mikołaj Skowron ◽  
Agnieszka Surowiak ◽  
Przemysław Syrek
Keyword(s):  
Electric Field ◽  
Electric Fields ◽  
Electric Field Distribution ◽  
Working Space ◽  
Dry Conditions ◽  
Laboratory Investigations ◽  
Rotary Speed ◽  
Electrodynamic Separation ◽  
Conductive Properties ◽  
Static Electric Fields

AbstractStatic electric fields are used, among others, in technological processes such as electric separation. Electrodynamic separation is a process of separating two or more solid phases of various physical properties by electric field forces. The advantage of electrodynamic separation is possibility of obtaining separation of individual components in dry conditions. This eliminates many operations such as thickening, dewatering, hydrotransportation, additional drying which cause higher energy consumption and higher separation process costs. Efficiency of beneficiation depends on many factors such as: electric properties of feed components, feed particle size distribution, drum rotary speed, electric field intensity in working space of separator, configuration of electrodes or surrounding conditions.The paper presents the working of high-voltage drum separator. The analysis of electric field distribution in separator working space was done. Additionally, distribution of forces acting on particles of dielectric and conductive properties was examined, trajectories of charged particles movement were presented too. The laboratory investigations of electronic wastes were performed in two particle fractions: 0.25–0.5 mm and 0–0.25 mm. It was observed that as a result of selective charging of particles they separate according to surface ability to electrifying what allows to obtain selective separation of components being so-called electronic wastes. The application of electrodynamic drum separator allows to separate such elements as Ti, Cu, Fe, Pb, Sn from plastics occurring in electronic wastes.

scholarly journals Design of Cable Termination for AC Breakdown Voltage Tests

Energies ◽  
2019 ◽  
Vol 12 (16) ◽  
pp. 3075 ◽  
Author(s):  
Arthur F. Andrade ◽  
Edson G. Costa ◽  
Filipe L.M. Andrade ◽  
Clarice S.H. Soares ◽  
George R.S. Lira
Keyword(s):  
Electric Field ◽  
Electric Fields ◽  
Breakdown Voltage ◽  
Electric Field Distribution ◽  
International Standards ◽  
The Finite Element Method ◽  
Cable Model ◽  
Voltage Measurement ◽  
Insulating Material ◽  
Purpose Computer

International standards prescribe overvoltage tests to evaluate the insulating material performance of high-voltage cables. However, it is difficult to manage the electric fields at the cable ends when laboratory measurements are carried out because surface and external discharges occur at the cable termination. Therefore, this paper presents a procedure for designing cable terminations to reduce the electric field at the cable ends to appropriate levels even in the case of overvoltage tests. For this purpose, computer simulations of electric field distribution using the finite element method (FEM) were performed. A 35 kV cable model was employed as a sample. An voltage with RMS (root mean square) value of 300 kV was used as an overestimate of breakdown voltage for the internal insulating material. The cable termination model obtained through the proposed methodology allows an electric field reduction in air, preventing the occurrence of external discharges, and thus permitting the breakdown voltage measurement of the cable’s inner insulation.

Fluid Mixing Control Inside a Y-Shaped Microchannel by Using Electrokinetic Instability

2007 ◽  
Author(s):  
Zheyan Jin ◽  
Hui Hu
Keyword(s):  
Electric Field ◽  
Electric Fields ◽  
Fluid Mixing ◽  
Critical Voltage ◽  
Mixing Efficiency ◽  
Mixing Process ◽  
Static Electric Field ◽  
Electrokinetic Instability ◽  
Mixing Control ◽  
Static Electric Fields

An experimental study was conducted to further our understanding about the fundamental physics of electrokinetic instability (EKI) and to explore the effectiveness to enhance fluid mixing inside a Y-shaped microchannel by manipulating convective EKI waves. The dependence of the critical voltage of applied static electric field to trig EKI to generate convective EKI waves on the conductivity ratio of the two adjacent streams was quantified at first. The effect of the strength of the applied static electric field on the evolution of the convective EKI waves and fluid mixing process were assessed in terms of scalar concentration fields, shedding frequency of the convective EKI waves and scalar mixing efficiency. The effectiveness of manipulating the convective EKI waves by introducing alternative electric perturbations to the applied static electric fields was also explored for the further enhancement of the fluid mixing process inside the Y-shaped microchannel.

Study on Electric Field Characteristics of Converter Transformer on Valve Side Winding

2011 ◽  
Vol 130-134 ◽  
pp. 1413-1417
Author(s):  
You Hua Gao ◽  
Guo Wei Liu ◽  
Yan Bin Li ◽  
You Feng Gao
Keyword(s):  
Electric Field ◽  
Field Distribution ◽  
Electric Fields ◽  
High Voltage ◽  
Electric Field Distribution ◽  
Influence Factors ◽  
Calculation Model ◽  
Dc Voltage ◽  
Voltage Polarity ◽  
Transient Electric Field

Numerical calculation model with compound insulation of transient electric field is given. The insulation is more prominent due to complication for voltage applied on valve side winding of the converter transformer. So the simplied structure for electric calculation on the valve side winding of the converter transformer is established. The electric field distribution characteristics on the valve side winding of the converter transformer is analyzed and electric fields in different resistivity and permittivity are calculated under AC high voltage, DC high voltage, AC superimposed DC voltage, polarity reversal voltage. The maximum electric field intensity is calculated and analyzed under kinds of high voltage. Some important influence factors for electric field distribution are also discussed in this paper.

The Experimental Study on the Influence of Human Body to Measurement of High Voltage Power Frequency Electric Field

2013 ◽  
Vol 303-306 ◽  
pp. 482-488
Author(s):  
Kai Mao ◽  
Jin Gang Wang ◽  
Xu Dong Deng ◽  
Wei He ◽  
Zuo Peng Zhang
Keyword(s):  
Electromagnetic Field ◽  
Electric Field ◽  
Electric Fields ◽  
High Voltage ◽  
Human Body ◽  
Enhancement Factor ◽  
Electric Field Distribution ◽  
Field Distortion ◽  
Power Frequency ◽  
Frequency Electric Field

Based on the basic theory of electromagnetic field, the Electric Field Distortion (EFD) in power frequency electric field caused by induced current of human body has been analyzed. The enhancement factor of the electric field distortion is introduced to reduce the influences caused by human body in the measurement of high voltage electric fields. The Ansoft Maxwell is used to simulate and calculate the electric field distribution under the influence of the human body to have the value of enhancement factor. In addition, the enhancement factor has been corrected by experiment with the electromagnetic field analyzer EFA300. With the enhancement factor introduced in this paper, the measurement error can be reduced.

scholarly journals Electric field assisted alignment of monoatomic carbon chains

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Stella Kutrovskaya ◽  
Igor Chestnov ◽  
Anton Osipov ◽  
Vlad Samyshkin ◽  
Irina Sapegina ◽  
...  
Keyword(s):  
Electric Field ◽  
Electric Fields ◽  
X Ray Diffraction ◽  
Laser Ablation Process ◽  
Carbon Chains ◽  
High Resolution Tem ◽  
The Difference ◽  
A Chain ◽  
Quasi Crystals ◽  
Static Electric Fields

Abstract We stabilize monoatomic carbon chains in water by attaching them to gold nanoparticles (NPs) by means of the laser ablation process. Resulting nanoobjects represent pairs of NPs connected by multiple straight carbon chains of several nanometer lengths. If NPs at the opposite ends of a chain differ in size, the structure acquires a dipole moment due to the difference in work functions of the two NPs. We take advantage of the dipole polarisation of carbon chains for ordering them by the external electric field. We deposit them on a glass substrate by the sputtering method in the presence of static electric fields of magnitudes up to 105 V/m. The formation of one-dimensional carbyne quasi-crystals deposited on a substrate is evidenced by high-resolution TEM and X-ray diffraction measurements. The original kinetic model describing the dynamics of ballistically flowing nano-dipoles reproduces the experimental diagram of orientation of the deposited chains.

The structure of the impulse corona in a rod/plane gap. II. The negative corona: propagation and streamer/anode interaction

1979 ◽  
Vol 367 (1730) ◽  
pp. 321-342 ◽  
Keyword(s):  
Simple Model ◽  
Electric Field ◽  
Space Charge ◽  
Electric Fields ◽  
Electric Field Distribution ◽  
Electron Lifetime ◽  
Gas Temperature ◽  
Negative Corona ◽  
Negative Impulse ◽  
Total Electric Field

The electric fields due to negative impulse corona space charge in a 0.5 m rod/plane gap have been investigated with a rotating fluxmeter probe. Spatial development has also been studied by simultaneous photography. The results indicate that a total electric field of about 1.8 MV m-1 is required near the head of the streamer for propagation, and a simple model is proposed of the electric field distribution in the gap at various stages of development. Measurements of transfer charge, due to interaction of streamers with the plane, yield estimates of the free electron lifetime and the gas temperature in the streamer. Possible models of the charge distribution in streamers are considered, with their associated electric fields, and best agreement with the data is obtained when most of the space charge is assumed to be concentrated at the tip. Comparison is made with earlier work on positive coronas.

scholarly journals Time-Dependent Electric Field Distribution in Layered Paper-Oil Insulation

2019 ◽  
pp. 58-63 ◽  
Author(s):  
Gunnar Håkonseth ◽  
Erling Ildstad
Keyword(s):  
Electric Field ◽  
Field Distribution ◽  
Electric Fields ◽  
Current Density ◽  
Test Object ◽  
Dielectric Response ◽  
Electric Field Distribution ◽  
Time Dependent ◽  
Polarization Current ◽  
Dependent Polarization

Layered paper–oil insulation is used in several types of HVDC equipment. In order to better understand breakdown mechanisms and optimize the design, it is important to understand the electric field distribution in the insulation. In the present work, a test object with such insulation has been modeled as a series connection of oil and impregnated paper. The permittivity, conductivity, and the dielectric response function has been measured for impregnated paper and oil separately and used as parameters in a dielectric response model for the layered insulation system. A system of differential equations has been established describing the voltages across each material, i.e. across each layer of the test object. These equations have been solved considering a DC step voltage across the whole test object. Based on this, the time-dependent electric field in each material as well as the time-dependent polarization current density in the test object have been calculated. The calculated polarization current density was found to agree well with the measured polarization current density of the test object. This indicates that application of dielectric response theory gives a good estimate of the time-dependent electric field distribution in layered insulation systems. The results show that 90 % of the change from initial values to steady-state values for the electric fields has occurred within the first 35 minutes after the voltage step. This applies to the electric fields in both of the materials of the examined test object at a temperature of 323 K.

Impedance Measurement in Multilayer Connecter System of Micro Channel With Different Frequency

2009 ◽  
Author(s):  
Je-Eun Choi ◽  
Masahiro Takei
Keyword(s):  
Electric Field ◽  
Electric Fields ◽  
Driving Force ◽  
Electric Field Distribution ◽  
Impedance Measurement ◽  
Flow Dynamics ◽  
Uniform Electric Field ◽  
Force Distribution ◽  
View Point ◽  
Tomography System

In investigating a microchannel, understanding regarding dispersion reaction are need to be acquire first down to the view point of multiphase flow dynamics. Usually, various measurements methods and in-depth analyzation are necessary to understand thoroughly the inside reaction occurs in this kind of system. In this experiment, fabricated multilayer microchannel with commercial connecter system was made for a tomography system with electrodes attached. This fabricated multilayer microchannel measures impedance using 12 electrodes from 5 different positions continuously. In measuring the impedance, it is necessary to consider the electric field caused by the electrodes and the force distribution inside the particles. Because of a non-uniform electric field distribution inside the system, forces inside the particles are not equal thus net force is present. This study, discuss how the frequency of the electric fields affects the particle position as a driving force to the microchannel system.

scholarly journals Electric Field Distribution Analysis of Blood Cancer as a Potential Blood Cancer Therapy

2021 ◽  
Vol 22 (2) ◽  
pp. 127
Author(s):  
Miftakhul Firdhaus ◽  
Ulya Farahdina ◽  
Vinda Zakiyatuz Zulfa ◽  
Endarko Endarko ◽  
Agus Rubiyanto ◽  
...  
Keyword(s):  
Cancer Therapy ◽  
Electric Field ◽  
Field Distribution ◽  
Electric Fields ◽  
B Lymphocyte ◽  
Electric Field Distribution ◽  
Input Voltage ◽  
Electrochemical Process ◽  
Distribution Analysis ◽  
Blood Cancer

Blood cancer causes a significant increase in the concentration of Leukocytes, which can be broken down through dielectrophoresis and electrochemical procedures. Therefore, the electric field plays an important role in the migration of leukocytes to high voltage areas. This is because different electrode arrangements produce varying electric field distributions. Furthermore, this study applied finite element methods to generate electric fields when electrodes with an AC voltage were applied to blood placed in a chamber. Therefore, in this study, variations of mediums and electrode arrangements were investigated, which led to the recommendation of 3 models. The objective was to investigate electrode arrangements that produce optimal electric field distribution for the three models to exhibit a booster of electric field distribution. The maximum electric field is generated close to the electrode (Z=2 mm and Z=92 mm) for any material (i.e. normal blood, B lymphocyte, and T lymphocyte) with values of 22.6 V/m and 23.47 V/m, 22.85 V/m and 22.97 V/m, and 24.88 V/m and 25.01 V/m. Based on principle, lymphocytes in the blood result in positive dielectrophoresis, since they migrate to a higher electric field close to the electrode, with enough input voltage to turn the electrochemical process on the leukocytes into electric current. Furthermore, this study provides new perspectives and ideas, which have not been revealed in previous studies on blood cancer therapy using the electric field of Ag electrode in blood cancer distribution.Keywords: blood cancer, dielectrophoresis, electric field, voltage, electrochemical, and cancer therapy.

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