scholarly journals Influence of elements thickness of separation devices on the finely dispersed particles collection efficiency

2018 ◽  
Vol 224 ◽  
pp. 02073 ◽  
Author(s):  
Andrey V. Dmitriev ◽  
Vadim E. Zinurov ◽  
Oksana S. Dmitrieva
Keyword(s):  
Flow Structure ◽  
Gas Flow ◽  
Collection Efficiency ◽  
Separation Process ◽  
Process Efficiency ◽  
Dust Particles ◽  
Optimum Thickness ◽  
Beam Elements ◽  
Dispersed Particles ◽  
Separation Devices

This article presents a rectangular separator, developed by the authors, for purification of a multiphase gas flow from the finely dispersed particles with a diameter of up to 10 µm. In order to increase the separation process efficiency, a research was conducted to determine the optimum thickness of I-beam elements within the separator at different values of the flow inlet rate and length of I-beam elements. It was found that change in the wall thickness of elements leads to a change in the flow structure, which causes a decrease in the dust particles collection efficiency.

Numerical Optimization of a Gravity Dust-Catcher for Improving Operation Efficiency

2017 ◽  
Author(s):  
Yifan Wang ◽  
Armin K. Silaen ◽  
Guangwu Tang ◽  
David Barker ◽  
Chenn Q. Zhou
Keyword(s):  
Blast Furnace ◽  
Gas Flow ◽  
Collection Efficiency ◽  
Total Suspended Solid ◽  
Suspended Solid ◽  
Operating Conditions ◽  
Process Efficiency ◽  
Dust Particles ◽  
Discrete Phase Model ◽  
Dust Catcher

Gravity dust-catchers are widely utilized in steelmaking plants to separate particles from the gas flow produced by the blast furnace (BF). The BF recycle system often experiences high total suspended solid (TSS) levels with a significant increase in sludge generation. This increased sludge generation results in higher costs in operation, chemical treatment and sludge removal. Due to the environmental limitations inside an operating dust-catcher, direct measurement of operating conditions can be extremely difficult. Computational fluid dynamics (CFD) models provide a method of gaining an understanding of the operating conditions and phenomena that occur inside a blast furnace dust-catcher on both full process and detailed levels. In this paper, a numerical geometry of the dust-catcher is designed and simulated under typical operating conditions. The Discrete Phase Model (DPM) is employed to track the flow patterns and paths of dust particles. The collection efficiency performance is evaluated at different conditions (quarter full, half full, and three quarter full). From these results, an alternative design to enhance process efficiency is proposed and investigated.

scholarly journals Study of the structure of gas flow іn a cyclone wіth іntermedіate dust removal

2021 ◽  
pp. 48-54
Author(s):  
Volodymyr Maistruk
Keyword(s):  
Gas Flow ◽  
Radial Component ◽  
Tangential Component ◽  
Separation Process ◽  
Dust Removal ◽  
Dust Particles ◽  
Axial Component ◽  
Exhaust Pipe ◽  
Conical Part ◽  
Annular Space

The works in which designs of the dust collectors, which are often used in the industry, are analyzed. It is shown that the efficiency of dust collectors largely depends on the structure of the gas flow in the apparatus. Based on the analysis of the current cyclone devices, a picture of the separation process is obtained, and the factors that negatively affect the operation of dust collectors are identified. It is established that forecasting the work of dust collecting devices in certain conditions is most effective to perform methods of numerical modeling and simulation of the separation process, which are widely used for the research of devices of this type. Using the methods of numerical simulation, the study of the cyclone with intermediate dust removal was carried out. In this cyclone, the change in the radius of the apparatus of the tangential, radial, and axial velocity components is investigated. In the course of the research, it is established that in the separation space the tangential component of velocity increases from 18–20 m/s in the upper part of the device to 22–25 m/s in the area of the lower end of the exhaust pipe, the radial component of velocity takes values from 0 to 2 m/s, and the axial component of the speed has a maximum value of 10–15 m/s. In the conical part of the apparatus the tangential component of velocity decreases from 27 m/s in the upper planes of the conical part of the apparatus to 10 m / s near the dust unloading pipe, the radial component of speed has centripetal character, the axial component of speed decreases as the gas flow to the dust unloading pipe decreases. It has been established that in the cylindrical part of the apparatus about 60 % of the gas flow volume is transferred from the downstream to the upstream by a secondary vortex, and in the conical part, about 40 % of the gas volume is transferred from the downstream to the upstream. It is shown that large values of the tangential component of velocity in the separation zone contribute to the ingress of dust particles into the annular space behind the dust unloading holes, and small values of the tangential component of velocity, axial and radial in the annular space behind the dust unloading holes has a positive effect on the operation of the dust collector.

scholarly journals EVALUATION OF THE INFLUENCE OF ELECTRIC WIND ON THE EFFICIENCY OF DISPERSED PARTICLES REMOVAL FROM THE FLUE GAS STREAM IN ELECTROSTATIC PRECIPITATORS

2019 ◽  
pp. 25-32
Author(s):  
V.A. Raschepkin ◽  
I.A. Volchyn
Keyword(s):  
Flue Gas ◽  
Gas Flow ◽  
Solid Particles ◽  
Dust Particles ◽  
Electric Wind ◽  
Dispersed Particles ◽  
Electrode Space ◽  
Electrostatic Precipitators ◽  
Different Diameters ◽  
Probabilistic Nature

The question of influence of the electric wind on efficiency of dispersed particles removal from a flue gas stream in electrostatic filters has not been studied well enough. Estimates are given of the role and influence of electric wind on the particle trapping processes in industrial electrostatic precipitators, as well as the results of experiments and calculations using aplied computational fluid dynamics packages. The results of mathematical modeling of the speed of dust particles of different diameters under the action of electric wind in the inter-electrode space of a corona discharge are presented; and the effects of turbulence of a gas flow on the particles capturing, the influence of the near-wall jet and the probabilistic nature of the removal of solid particles from the dusted exhaust gas flow are evaluated. Ref. 18, Fig. 5.

scholarly journals Separation of Fine Particles from Gas in Paint-Spraying Booths

2021 ◽  
Vol 346 ◽  
pp. 03070
Author(s):  
Rustem Ya. Bikkulov ◽  
Andrey V. Dmitriev ◽  
Vadim E. Zinurov ◽  
Guzel R. Badretdinova
Keyword(s):  
Gas Flow ◽  
Fine Particles ◽  
Solid Particles ◽  
Dust Particles ◽  
Technological Parameters ◽  
Separation Device ◽  
Dispersed Particles ◽  
Quality Of Products ◽  
The Impact

Nowadays, at production facilities with paint-spraying booths that use paint and varnish materials to cover the surfaces of product, the problem of gas flow contamination with finely dispersed solid particles of dust and rubbish, which negatively affect the quality of products, is increasingly being raised. In order to minimize the content of solid particles in the gas flow, coarse and fine filters are installed in the paint-spraying booths, which prevent dust particles from entering the surface of products. However, the existing purification devices have a number of disadvantages that affect the efficiency of collecting finely dispersed particles from the gas flow with a size of 0.5-5 microns. The authors of article developed a square separator to increase the efficiency of collecting finely dispersed particles from gas flows in the paint-spraying booths. The installation of proposed separation device in the paint-spraying booths affects not only the quality of collecting solid particles, but also increases the service life of fine and coarse filters In the course of numerical studies, the results of impact of structural and technological parameters, namely, the impact of inlet rate and scale of separation device on the efficiency of collecting solid particles from the gas flow, were obtained.

Electrohydrodynamic gas flow in a positive polarity wire-plate electrostatic precipitator and the related dust particle collection efficiency

2006 ◽  
Vol 64 (3-4) ◽  
pp. 259-262 ◽  
Author(s):  
Janusz Podliński ◽  
Jarosław Dekowski ◽  
Jerzy Mizeraczyk ◽  
Drazena Brocilo ◽  
Jen-Shih Chang
Keyword(s):  
Dust Particle ◽  
Gas Flow ◽  
Electrostatic Precipitator ◽  
Collection Efficiency ◽  
Positive Polarity ◽  
Particle Collection

scholarly journals Experimental Research of Gaseous Emissions Impact on the Performance of New-Design Cylindrical Multi-Channel Cyclone with Adjustable Half-Rings

2022 ◽  
Vol 14 (2) ◽  
pp. 902
Author(s):  
Aleksandras Chlebnikovas ◽  
Dainius Paliulis ◽  
Kristina Kilikevičienė ◽  
Artūras Kilikevičius
Keyword(s):  
Experimental Research ◽  
Gas Flow ◽  
Collection Efficiency ◽  
Fine Particulate Matter ◽  
Air Flow ◽  
Gaseous Emissions ◽  
Channel System ◽  
Flow Parameters ◽  
The Impact ◽  
Channel Type

Cyclones are widely used for separating particles from gas in energy production objects. The efficiency of conventional centrifugal air cleaning devices ranges from 85 to 90%, but the weakness of many cyclones is the low collection efficiency of particles less than 10 μm in diameter. The novelty of this work is the research of the channel-type treatment device, with few levels adapted for precipitation of fine particulate matter, acting by a centrifugal and filtration principle. Many factors have an impact on cyclone efficiency—humidity, temperature, gas (air) composition, airflow velocity and etc. Many scientists evaluated only the effect of origin and size of PM on cyclone efficiency. The effect of gas (air) composition and temperature, and humidity on the multi-channel cyclone-separator efficiency still demands contributions. Complex theoretical and experimental research on air flow parameters and the efficiency of a cylindrical eight-channel system with adjustable half-rings for removing fine-dispersive particles (<20 μm) was carried out. The impact of air humidity and temperature on air flow, and gaseous smoke components on the removal of wood ashes was analyzed. The dusty gas flow was regulated. During the experiment, the average velocity of the cyclone was 16 m/s, and the temperature was 20–50 °C. The current paper presents experimental research results of wood ash removal in an eight-channel cyclone and theoretical methodology for the calculation of airflow parameters and cyclone effectiveness.

Flow Structure and Heat Transfer in Stagnation Flow CVD Reactor

2010 ◽  
Author(s):  
Nasir Memon ◽  
Yogesh Jaluria
Keyword(s):  
Heat Transfer ◽  
Flow Structure ◽  
Atmospheric Pressure ◽  
Gas Flow ◽  
Flow Reactor ◽  
Chemical Vapor ◽  
Design Parameters ◽  
Stagnation Flow ◽  
Inlet Length ◽  
The Impact

An experimental study is undertaken to investigate the flow structure and heat transfer in a stagnation flow Chemical Vapor Deposition (CVD) reactor at atmospheric pressure. It is critical to develop models that predict flow patterns in such a reactor to achieve uniform deposition across the substrate. Free convection can negatively affect the gas flow as cold inlet gas impinges on the heated substrate, leading to vortices and disturbances in the normal flow path. This experimental research will be used to understand the buoyancy-induced and momentum-driven flow structure encountered in an impinging jet CVD reactor. Investigations are conducted for various operating and design parameters. A modified stagnation flow reactor is built where the height between the inlet and substrate is reduced when compared to a prototypical stagnation flow reactor. By operating such a reactor at certain Reynolds and Grashof numbers it is feasible to sustain smooth and vortex free flow at atmospheric pressure. The modified stagnation flow reactor is compared to other stagnation flow geometries with either a varied inlet length or varied heights between the inlet and substrate. Comparisons are made to understand the impact of such geometric changes on the flow structure and the thermal boundary layer. In addition, heat transfer correlations are obtained for the substrate temperature. Overall, the results obtained provide guidelines for curbing the effects of buoyancy and for improving the flow field to obtain greater film uniformity when operating a stagnation flow CVD reactor at atmospheric pressure.

Influence of Applied Magnetic Field on a Wire-Plate Electrostatic Precipitators Under Multi-Field Coupling

2013 ◽  
Vol 135 (8) ◽  
Author(s):  
Jian-Ping Zhang ◽  
Yong-Xia Dai ◽  
Jiong-Lei Wu ◽  
Jian-Xing Ren ◽  
Helen Wu ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Applied Magnetic Field ◽  
Fine Particles ◽  
Collection Efficiency ◽  
Mathematic Model ◽  
Average Diameter ◽  
Dust Particles ◽  
Particle Dynamic ◽  
Electrostatic Precipitators ◽  
The Magnetic Field

The aim of this work is to find an effective method to improve the collection efficiency of electrostatic precipitators (ESPs). A mathematic model of an ESP subjected to the external magnetic field was proposed. The model considered the coupled effects between the gas flow field, particle dynamic field and electromagnetic field. Particles following a Rosin-Rammler distribution were simulated under various conditions and the influence of the magnetic field density on the capture of fine particles was investigated. The collection efficiency and the escaped particle size distribution under different applied magnetic field intensities were discussed. Particle trajectories inside the ESP under aerodynamic and electromagnetic forces were also analyzed. Numerical results indicate that the collection efficiency increases with the increase of applied magnetic field. It was also found that a stronger applied magnetic field results in a larger particle deflection towards the dust collection plates. Furthermore, the average diameter of escaping particles decreases and the dispersion of dust particles with different sizes increases with the increasingly applied magnetic field. Finally, the average diameter decreases almost linearly with the magnetic field until it drops to a certain value. The model proposed in this work is able to obtain important information on the particle collection phenomena inside an industrial ESP under the applied magnetic field.

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