scholarly journals Studying the possibilities of improving centrifugal separation efficiency

2020 ◽  
pp. 80-86
Author(s):  
Iurii Morozov ◽  
◽  
Pavel Penkov ◽  
Keyword(s):  
High Efficiency ◽  
Separation Efficiency ◽  
Technical Solution ◽  
Centrifugal Separation ◽  
Centrifugal Separator ◽  
Gold Extraction ◽  
Valuable Component ◽  
Heavy Residue ◽  
Flow Through ◽  
The Given

Object and aim of research. One direction in improving valuable components extraction in centrifugal separation is to apply it in the scheme of circular concentration. By means of multiple passing of a pulp flow through the centrifugal separator, higher indicators of valuable component extraction in heavy residue are ensured. The aim of this research is to study the possibility of improving the efficiency of centrifugal separation based on float circulation. Methodology. Laboratory testing has been carried out to cope with the given task. Centrifugal separation has been fulfilled in a laboratory fortex formation centrifugal separator K-200VL under the cone rotation 86 "Izvestiya vysshikh uchebnykh zavedenii. Gornyi zhurnal". No. 3. 2020 ISSN 0536-1028 frequency of 1000 r/min. Hydrocycloning has been carried out in cyclone separator GTs-75 with the apex diameter of 1.7 cm. The obtained concentrate and tailings were subject to gold assay test. According to the results of the assay test, the calculation of gold extraction in heavy residue and float has been fulfilled. Summary. The obtained result testifies to high efficiency of the proposed technical solution. The proposed technical solution ensures improved efficiency of the process by means of increasing the extraction of particles of increased density in the concentrate when increasing its quality and reducing specific water consumption for the process

scholarly journals Separation of minerals in a centrifugal field using circulating concentration

2020 ◽  
Vol 177 ◽  
pp. 01005
Author(s):  
Pavel Penkov ◽  
Yuri Morozov
Keyword(s):  
High Speed ◽  
Wall Layer ◽  
Light Fraction ◽  
Solid Particles ◽  
Centrifugal Separation ◽  
Centrifugal Separator ◽  
Centrifugal Field ◽  
Valuable Component ◽  
Laboratory Conditions ◽  
Increased Pressure

Due to the high speed of rotation of the centrifugal separator cone, it is possible to separate particles of small sizes. In its turn, the high speed of rotation of the centrifugal separator cone leads to clogging of the grooves of the separator cone with solid particles. The increased pressure of the turbulizing agent contributes to the loosening of solid particles in the grooves of the centrifugal separator cone, but can wash out particles with increased density from the grooves. Also, the loss of a valuable component is associated with the fact that particles of a valuable component located on the surface of the near-wall layer do not have time to get into the grooves in one cycle and are washed out of the separator cone together with the light fraction. In this regard, there is a need to study the increase in centrifugal separation using it in the circulating concentration scheme. Experiments were carried out in laboratory conditions on an artificial mixture of tungsten and quartz. The results of the experiments show an increase in enrichment rates.

scholarly journals STUDY OF GOLD EXTRACTION FROM STALE TAILINGS BY AGITATION LEACHING

2021 ◽  
pp. 89-94
Author(s):  
A. Altayeva ◽  
B. N. Surimbayev ◽  
L. S. Bolotova ◽  
Zh. Т. Bagasharova ◽  
Sh. K. Akilbekova
Keyword(s):  
High Efficiency ◽  
Raw Materials ◽  
Material Composition ◽  
Processing Plant ◽  
Gold Content ◽  
Mineralogical Analysis ◽  
Gold Extraction ◽  
Initial Size ◽  
Valuable Component ◽  
Gold Silver

The object of research is technogenic mineral formations-tailings of the Bestube processing plant located within the Bestube gold field. Analytical and technological studies of stale tailings have been carried out. According to the results of analytical studies, the material composition of stale tails was established. The average gold content in stale tailings according to assay analyses is 0.565 g/t, silver 1.56 g/t. The tailings belong to the category of poor sulfide, oxidized raw materials. The main industrially valuable component in the tailings is gold, silver has a subordinate value, and other metals are not of industrial value. Mineralogical analysis established that stale tails are represented by quartz, muscovite, clinochlore, albite, dolomite. Studies were conducted on agitation leaching of stale tailings of the initial size (64.08% of the class –0.074 mm) and after additional grinding to the size of 90% of the class –0.074 mm. Reducing the size contributes to the dissolution of gold from the tailings: at the initial size, 66.28% of gold is dissolved, after regrinding the degree of dissolution of gold from the tailings increases to 87.23%. The results of research on agitation leaching of gold have shown a high efficiency of hydrometallurgical technology for processing stale tailings of a processing plant.

Drying and heating of scrap metal at steelmaking: industrial safety, economics, ecology

2020 ◽  
Vol 76 (12) ◽  
pp. 1353-1258
Author(s):  
V. A. Spirin ◽  
V. E. Nikol’skii ◽  
D. V. Vokhmintsev ◽  
A. A. Moiseev ◽  
P. G. Smirnov ◽  
...  
Keyword(s):  
Energy Efficiency ◽  
High Efficiency ◽  
Steel Production ◽  
Scrap Metal ◽  
Industrial Safety ◽  
Technical Solution ◽  
Metal Charge ◽  
Basic Task ◽  
Scrap Heating ◽  
Winter Time

At steel production based on scrap metal utilization, the scrap heating before charging into a melting facility is an important way of energy efficiency increase and ecological parameters improving. In winter time scrap metal charging with ice inclusions into a metal melt can result in a considerable damage of equipment and even accidents. Therefore, scrap preliminary drying is necessary to provide industrial safety. It was shown, that in countries with warm and low-snow climate with no risk of scrap metal icing up during its transportation and storing in the open air, the basic task being solved at the scrap drying is an increase of energy efficiency of steelmaking. InRussiathe scrap metal drying first of all provides the safety of the process and next - energy saving. Existing technologies of scrap metal drying and heating considered, as well as advantages and drawbacks of technical solutions used at Russian steel plants. In winter time during scrap metal heating at conveyers (Consteel process) hot gases penetrate not effectively into its mass, the heat is not enough for evaporation of wetness in the metal charge. At scrap heating by the furnace gases, a problem of dioxines emissions elimination arises. Application of shaft heaters results in high efficiency of scrap heating. However, under conditions of Russian winter the upper scrap layers are not always heated higher 0 °С and after getting into a furnace bath the upper scrap layers cause periodical vapor explosions. The shaft heaters create optimal conditions for dioxines formation, which emit into atmosphere. It was shown, that accounting Russian economic and nature conditions, the metal charge drying and heating in modified charging buckets by the heat of burnt natural gas or other additional fuel is optimal. The proposed technical solution enables to burnt off organic impurities ecologically safely, to melt down ice, to evaporate the wetness in the scrap as well as to heat the charge as enough as the charging logistics enables it. The method was implemented at several Russian steel plants. Technical and economical indices of scrap metal drying in buckets under conditions of EAF-based shop, containing two furnaces ДСП-100, presented.

Recent Advances in Heterostructured Photocatalysts for Degradation of Organic Pollutants.

2020 ◽  
Vol 17 ◽  
Author(s):  
Chen-Jing Sun ◽  
Li-Ping Zhao ◽  
Rui Wang
Keyword(s):  
Organic Pollutants ◽  
High Efficiency ◽  
Separation Efficiency ◽  
Organic Pollution ◽  
Utilization Rate ◽  
Type I ◽  
Human Beings ◽  
Global Challenge ◽  
Global Environmental ◽  
High Efficient

: With the development of industrialization, the global environmental pollution and energy crisis are becoming increasingly serious. Organic pollutants pose a serious health threat to human beings and other organisms. The removal of organic pollutants in environment has become a global challenge. The photocatalytic technology has been widely used in the degradation of organic pollutants with its characteristics of simple process, high efficiency, thorough degradation and no secondary pollution. However, the single photocatalyst represented by TiO2 has disadvantages of low light utilization rate and high recombination rate of photocarriers. Building heterojunction is considered one of the most effective methods to enhance the photocatalytic performance of single photocatalyst, which can improve the separation efficiency of photocarriers and utilization of visible light. The classical heterojunction can be divided into four different cases: type I, typeⅡ, p–n heterojunctions and Z-scheme junction. In this paper, the recent progress in the treatment of organic pollution by heterostructure photocatalysts is summarized and the mechanism of heterostructure photocatalysts for the treatment of organic pollutants is reviewed. It is expected that this paper can deepen the understanding of heterostructure photocatalysts and provide guidance for high efficient photocatalytic degradation of organic pollutants in the future.

"Recent Patents on the Triboelectrostatic Separation of Fly Ash"

2019 ◽  
Vol 13 ◽  
Author(s):  
Haisheng Li ◽  
Wenping Wang ◽  
Yinghua Chen ◽  
Xinxi Zhang ◽  
Chaoyong Li
Keyword(s):  
Fly Ash ◽  
Power Plants ◽  
High Efficiency ◽  
Separation Efficiency ◽  
High Reliability ◽  
Operating Conditions ◽  
Security Requirements ◽  
Unburned Carbon ◽  
Efficient Operation ◽  
Triboelectrostatic Separation

Background: The fly ash produced by coal-fired power plants is an industrial waste. The environmental pollution problems caused by fly ash have been widely of public environmental concern. As a waste of recoverable resources, it can be used in the field of building materials, agricultural fertilizers, environmental materials, new materials, etc. Unburned carbon content in fly ash has an influence on the performance of resource reuse products. Therefore, it is the key to remove unburned carbon from fly ash. As a physical method, triboelectrostatic separation technology has been widely used because of obvious advantages, such as high-efficiency, simple process, high reliability, without water resources consumption and secondary pollution. Objective: The related patents of fly ash triboelectrostatic separation had been reviewed. The structural characteristics and working principle of these patents are analyzed in detail. The results can provide some meaningful references for the improvement of separation efficiency and optimal design. Methods: Based on the comparative analysis for the latest patents related to fly ash triboelectrostatic separation, the future development is presented. Results: The patents focused on the charging efficiency and separation efficiency. Studies show that remarkable improvements have been achieved for the fly ash triboelectrostatic separation. Some patents have been used in industrial production. Conclusion: According to the current technology status, the researches related to process optimization and anti-interference ability will be beneficial to overcome the influence of operating conditions and complex environment, and meet system security requirements. The intelligent control can not only ensure the process continuity and stability, but also realize the efficient operation and management automatically. Meanwhile, the researchers should pay more attention to the resource utilization of fly ash processed by triboelectrostatic separation.

Improving the accuracy of forming a digital terrain model along the railway

2021 ◽  
pp. 22-29
Author(s):  
Dmitriy A. Roshchin
Keyword(s):  
High Efficiency ◽  
Digital Terrain Model ◽  
Digital Processing ◽  
Aerial Photographs ◽  
Railway Track ◽  
Technical Solution ◽  
Digital Terrain Models ◽  
Terrain Model ◽  
Digital Terrain ◽  
Terrain Models

The problem of improving the accuracy of digital terrain models created for monitoring and diagnostics of the railway track and the surrounding area is considered. A technical solution to this problem is presented, which includes a method for joint aerial photography and laser scanning, as well as a method for digital processing of the obtained data. The relevance of using this solution is due to the existence of zones of weak reception of signals from the global navigation satellite system, since in these zones the accuracy of constructing digital terrain models using currently used diagnostic spatial scanning systems is reduced. The technical solution is based on the method of digital processing of aerial photographs of the railway track. In this case, as elements of external orientation, the threads of the rail track located at a normalized distance from each other are used. The use of this method made it possible to increase the accuracy of determining the flight path of an aircraft over railway tracks and, as a result, the accuracy of calculating the coordinates of points on the earth's surface. As a result, a digital terrain model was created that is suitable for diagnostics and monitoring the condition of the railway trackbed. During simulation modeling, it was found that the application of the proposed method allowed to reduce to 50 % the confidence interval of the distribution of the error in determining the coordinates of points on the terrain and increase the accuracy of forming a digital terrain model. This promising technical solution for improving the accuracy of digital terrain models for railway track diagnostics is implemented using unmanned aerial vehicles that are part of the mobile diagnostic complex. The advantages of the proposed solution include high efficiency and availability of application.

SIMULATION SCHEME MODELING OF THE SUPER-SPEED TIME BUFFER

2020 ◽  
Author(s):  
А.М. САЖНЕВ ◽  
Л.Г. РОГУЛИНА
Keyword(s):  
High Speed ◽  
High Efficiency ◽  
Low Cost ◽  
Circuit Modeling ◽  
Clock Signal ◽  
Behavioral Models ◽  
Software Environment ◽  
Time Buffer ◽  
The Given ◽  
Simulation Scheme

Приводятся результаты моделирования сверхскоростного буфера тактовых сигналов, выполненного на базе арсенид-галлиевых n-канальных транзисторов в среде OrCAD и полностью отвечающего следующим требованиям: высокие технические характеристики, малые размеры, высокая частота и КПД, гибкость применения. Приведенные поведенческие модели допускают использование любой программной среды по схемотехническому моделированию. The results of simulation of an ultra-high-speed clock signal buffer based on gallium arsenide n-channel transistors in OrCAD are presented, which fully meets the following requirements: high technical characteristics, application flexibility, low cost, small size, high frequency, and high efficiency. The given behavioral models allow the use of any software environment for circuit modeling.

Experimental and Numerical Investigation of Air-Particle Two-Phase Flow in Centrifugal Separator

2000 ◽  
Author(s):  
H. J. Kang ◽  
B. Zheng ◽  
C. X. Lin ◽  
M. A. Ebadian
Keyword(s):  
Velocity Distribution ◽  
Separation Efficiency ◽  
Three Dimensional ◽  
Vertical Direction ◽  
Tangential Direction ◽  
Cylinder Surface ◽  
Centrifugal Separator ◽  
Two Phase ◽  
Dust Collection ◽  
Numerical Solver

Abstract The velocity distributions inside a centrifugal separator with outside and inside diameters of 152.4 mm (6″) and 76.2 mm (3″), respectively, have been investigated experimentally and numerically to obtain optimum separation efficiency. Two 12.7 mm (1/2-inch) holes were drilled on the external surface of the separator to measure the velocity distribution in the separator. Two direction velocities (tangential direction along the cylinder surface and axial along the vertical direction) were measured to compare with the numerical simulation results. A 6060P Pitot probe was employed to obtain the velocity distribution. The dust samples (a mixture of steel particle and dust) from the dust collection box were analyzed using a Phillips XL30 Scanning Electron Microscope. FLUENT code is used as the numerical solver for this fully three-dimensional problem. The fluid flow in the separator is assumed to be steady and incompressible turbulent flow. The standard k–ε model was employed in this study. Non-uniform, unstructured grids are chosen to discretize the entire computation domain. Almost 100,000 cells are used to discretize the whole separator. The constant velocity profile is imposed on the inlet plane. The pressure boundary condition is adopted at outlet plane. Comparing the velocity distribution and separation efficiency from the experiment and the numerical modeling shows that the experimental results and the estimated data agree fairly well and with a deviation within ±10%.

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