Continuous production of polycrystalline silicon particles via CVD from SiHC13 or SiH4 has been proposed to increase thermal efficiency and to develop a continuous CZ furnace system. Several types of fluidized bed reactors for production of polycrystalline silicon particles via CVD have recently been developed/ 1 -7/.
Silicon particle growth in a fluidized-bed reactor. Abstract This paper describes the overall operation of a 15 cm dia. fluidized‐bed reactor for silicon production via silane pyrolysis. The fluidized‐bed reactor has been characterized by its performance data and parametric effects. A withdrawal system is used to selectively remove big ...
Numerical simulations of particle growth in a silicon-CVD fluidized bed reactor via a CFD–PBM coupled model May 2014 Chemical Engineering Science 111:112–125
The multiphase particle-in-cell method (MP-PIC) is a numerical method for modeling particle-fluid and particle-particle interactions in a computational fluid dynamics (CFD) calculation. The MP-PIC method achieves greater stability than its particle-in-cell predecessor by simultaneously treating the solid particles as computational particles and as a continuum.
This invention relates to silane pyrolysis in a fluidized bed. Fluidized bed silane pyrolysis, using fluidized sili- con particles to receive deposits of silicon product, can utilize a conventional boot separator collecting cham- ber below the fluidized bed to receive enlarged silicon product particles descending from the bed. The im-
Fluidization (or fluidisation) is a process similar to liquefaction whereby a granular material is converted from a static solid-like state to a dynamic fluid-like state.This process occurs when a fluid (liquid or gas) is passed up through the granular material.When a gas flow is introduced through the bottom of a bed of solid particles, it will move upwards through the bed via the empty ...
in a fluidized bed reactor, experimental studies of SiH4 pyrolysis and fine particle fluidization, and thermodynamic and chemical engineering analysis of the reactions in the fluidized process for silicon production. The initial phage of the effort in modeling is described in this report. 1- 1
of fluidized bed are pressure drop, fluid velocities, bubble size and bed height. Computational fluid dynamics (CFD) simulation is the method to study this project. Firstly, Ergun 6.2 software is used to study particle mixing and segregation phenomena. Secondly, 3D geometry of fluidized bed is drawn by using Solidworks 2012.
Nov 19, 2011· Growth of polycrystalline silicon from fluidized bed reactors (FBR) produces two general types of silicon products: granular material (diameters on the order of mm) and homogeneously nucleated material often called nanopowder (diameters in the range 10–100 nm). Nanopowder particles tend to be amorphous and have a spherical morphology with an average particle diameter of ~80 nm.
particle properties such as particle size, particle density, particle shape etc. and fluid properties (Fotovat, Ansart et al. 2015). However, there can be additional effects from the bed diameter, geometry, aspect ratio and distributor design as well. The transition superficial gas velocity from fixed bed to fluidized bed is referred to as
Good particle shape, narrow particle size distribution. ... Key parts like inner liner, classifying wheel and nozzle are made of ceramic such as aluminum oxide, zirconium oxide or silicon carbide, ensuring non-contact with metal throughout the grinding for high purity of the final ... Fluidized(Fluidised) bed opposed jet mill works with cyclone ...
a stable fluidization state and particle circulation rate. INTRODUCTION Solar grade silicon is in ever-increasing demand due to the rapid development of the photovoltaic (PV) industry (1 ). One challenge the PV industry is currently facing is the development of cheap solar grade silicon feedstock (2). The traditional method for
- production of silicon for the semi-conductor industry ... Group A Small particle size or density less than 1.4 g/cm3. Easily fluidized with ... fluidized bed will be employed in your chemical reaction engineering course in which you will assume that the bubbling bed is a well-mixed reactor. This is a reasonable approximation of a
Characteristics of fluidized bed reactor at high velocity fluidization . ..., clay and mica). The physical properties of these particles are given in table 2 below. The size of the particle listed in this table is evaluated by the mesh screen analysis. ... For instance, it was observed that sample A has the highest Silicon Oxide concentration ...
particle sizes, particle size distribution and superficial gas velocity are influencing on the flow behaviour and mixing. Fluidized bed reactors are used in production of silicon for solar cells. The gas-particle reaction is a continuous process where the particles are fully consumed during the reaction and the
Nov 29, 2018· REC Silicon uses a fluidized bed to produce purified silicon for photovoltaic cells as shown in the picture (Computational Particle Fluid Dynamics, 2016). Unlike the traditional method of covering seed rods with a superheated silicon gas, the method used by REC Silicon lets the seed granules to float inside a fluidized bed reactor.
In a fluidized bed, it is the drag force that counteracts the force of gravity which results in the bed being fully suspended. At high superficial gas velocities, particles become entrained and leave the bed. For a single particle, the determination of the drag force is straightforward, and is typically described by the kinetic energy times the ...
OSTI.GOV Journal Article: Silicon particle growth in a fluidized-bed reactor
Mixed-Particle Fluidized Beds Kevin D. Seibert and Mark A. Burns Dept. of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109 A statistical mechanical simulation was developed and used to predict the macro- scopic and microscopic behavior of fluidized …
A fluidized bed is a physical phenomenon occurring when a quantity of a solid particulate substance (usually present in a holding vessel) is placed under appropriate conditions to cause a solid/fluid mixture to behave as a fluid.This is usually achieved by the introduction of pressurized fluid through the particulate medium. This results in the medium then having many properties and ...
The particle concentration signals of silicon powder in the fluidizing gas i.e. air under different operating conditions were determined. The diameter of silicon particles, operating velocity, radial distance and axial distance are used as input vector; the mean value of particle concentration signal in the silicon power fluidized bed is used as a target vector.
The present invention is an improved process for the reaction of an alkyl halide with particulate silicon in a fluidized-bed process. The improvement comprises controlling the particle size of the silicon within a range of one micron to 85 microns. Preferred is when the particle size of the silicon has a mass distribution characterized by a 10th percentile of 2.1 to 6 microns, a 50th ...
This paper describes the overall operation of a 15 cm dia. fluidized-bed reactor for silicon production via silane pyrolysis. The fluidized-bed reactor has been characterized by its performance data and parametric effects. A withdrawal system is used to selectively remove big particles.
Jul 24, 2021· This video shows the short-time simulation of paddy drying in fluidized bed (only paddy motions are captured). T
tablets, or in a fluidized bed coater for smaller size dosage forms such as pellets, pills, granules etc. WPC solution may be volatile and toxic which needs consideration. Apart from that it requires post treatment and waste processing which subsequently increase the cost [9]. Wet particle coating techniques 1.2.1 Microencapsulation
The unit will use the fluidized particle-in-tube solar receiver concept. The scaling up of this concept needs researches on the gas-particle flow structure evolution along the tube and on wall-to-fluidized particles heat transfer. Therefore, several experimental set-ups were ... silicon carbide particles. The particle flowrate varied from 7.4 ...
in the freeboard region of a fluidized bed containing flu - idized catalytic cracking (FCC) equilibrium catalyst with a median particle size of 72 microns and 12 % fines (de-fined as particle with a size smaller than 44 microns). In fact, 30 % of the particle behavior in the freeboard was found to resemble particle cluster formation with an aver-
Aug 01, 2020· For the fluidized bed system developed in this study, the suggested fluidization parameters were: (a) silicon carbide particle size of 0.25–1 mm, (b) fluidization velocity of 0.47–-0.71 m/s, and (c) silicon carbide particle loading of 40–50 g.