CFD Simulation and Performance Analysis of CJD Burner for Intensified Flash Smelting Process

2012 ◽  
Author(s):  
Zhuo Chen ◽  
Peng Long ◽  
Zhiqiang Sun ◽  
Jun Zhou ◽  
Jiemin Zhou
Keyword(s):  
Cfd Simulation ◽  
Flash Smelting ◽  
Smelting Process ◽  
Flash Furnace ◽  
Discrete Phase Model ◽  
Reaction Shaft ◽  
Technical Problems ◽  
Dust Generation ◽  
Discrete Phase ◽  
And Performance

The flash smelting process has been widely acknowledged as a successful modern pyro-metallurgical technology because of its good production flexibility. In past decades, great efforts have been put on the equipment improvement in order to achieve a highly intensive and efficient flash smelting process. However, along with the increasing of the productivity and the intensification of the process, technical problems such as the un-smelted materials accumulated in the settler and the dust generation ratio going higher are found occurring more frequently than before. All these problems however indicate degeneration in the performance of the central jet distributor (CJD) burner. A study was then made on the combustion and reaction processes in the flash furnace equipped with a CJD burner. A steady-state turbulent model was developed and a discrete phase model was included to investigate the velocity and temperature changes of both the gaseous and particle phases in the reaction shaft. The deviation of the numerical model is estimated to be less than 6%. The simulation results reveal a serious delay in the ignition of concentrate particles after they are fed into the furnace. Minor modification was also made by CFD computation, attempting to improve the particle ignition speed, but it was found not so effective. The main reason for the decreased smelting efficiency is found to be the poor mixing between the gaseous and particle phases under the intensified condition. These appeal for a great improvement in the performance of the CJD burner.

CFD Simulation of Water Flow Mixing With Discrete Phase in a Pump

2013 ◽  
Author(s):  
Mikhail P. Strongin
Keyword(s):  
Particle Distribution ◽  
Cfd Simulation ◽  
Liquid Mixture ◽  
Industrial Applications ◽  
Discrete Phase Model ◽  
Water Transportation ◽  
Flow Mixing ◽  
Discrete Phase ◽  
The Subject ◽  
Pump Inlet

The mixing process is very common in many industrial applications. In some cases, two or more liquids or discrete phase (DP) set on the pump inlet. Liquid mixture is often occurred in sanitation and agriculture applications and mixture of water with DP (such as sand) are met in the case of water transportation from natural sources (rivers, wells, etc.). DP distribution in the centrifugal pump is the subject of this study. Full pump geometry is considered, due to unsymmetrical nature of volute of the pump. Turbulence k-ε closure model and Lagrangian discrete phase model has been used for most simulations. It was found that smaller particles trap inside the pump for longer time than larger ones. The distribution of the bigger diameter particles on the outlet is more asymmetrical in comparison with particles of smaller diameter. Relatively large areas with very small particle concentrations can be observed. Particle distribution on the outlet for lighter particles demonstrates more uniformity.

CFD Study on must of Grapes Separation in a Hydrocyclone

2013 ◽  
Vol 837 ◽  
pp. 645-650
Author(s):  
Petru Cârlescu ◽  
Ioan Tenu ◽  
Marius Baetu ◽  
Radu Rosca
Keyword(s):  
Cfd Simulation ◽  
Reynolds Stress Model ◽  
Continuous Phase ◽  
Solid Particles ◽  
Advanced Degree ◽  
Separation And Purification ◽  
Discrete Phase Model ◽  
Flow Rates ◽  
Discrete Phase ◽  
Simulation And Experiment

Abstract. Hydrocyclones are increasingly used in the food industry for various separation and purification. In this paper, an optimization was made to design a hydrocyclone model using CFD (Computational Fluid Dynamics). CFD simulation is performed with FLUENT software by coupling the Reynolds Stress Model (RSM) for must of grapes flow with Discrete Phase Model (DPM) for solid particles trajectory. Coupling of discrete phase (particles) and continuous phase (must of grapes) in the mathematical model is set so that the continuous phase to influence discrete phase. Tracking particles traiectory in this hydrocyclone allows advanced degree is separation so obtained to the maximum particle size approaching the size of a yeast cell 10 μm, without separating them. Hydrocyclone dimensional designed simulation was performed and analyzed on an experimental pilot plant for three different must flow rates supply. Introduced particle flow rates simulation and experiment does not exceed 10% of the must flow rates. The degree of separation obtained is in agreement with experimental data.

CFD Simulation of COVID Aerosol Dispersion in Indoor Environments

2021 ◽  
Author(s):  
Mohammed Abushamleh ◽  
Ning Zhang
Keyword(s):  
Relative Humidity ◽  
Cfd Simulation ◽  
Medium Size ◽  
Indoor Environments ◽  
Discrete Phase Model ◽  
Discrete Phase ◽  
Computational Fluid Dynamics Simulations ◽  
Aerosol Dispersion ◽  
Dynamics Simulations ◽  
Simulation Time

Abstract Computational Fluid Dynamics simulations for the droplet’s dispersion generated by a cough in an indoor background, droplets trajectory, and evaporation time are predicted to be related to the droplet’s diameter and relative humidity. In general, medium-size droplets have higher axial penetration potential, and large droplets tend to settle on the ground due to gravity. Also, larger droplets take a longer time to evaporate. Smaller droplets tend to be suspended in the flow field with small penetration potential and tend to fade faster; smaller droplets < 20 μm evaporate completely before the simulation time reaches 0.75 sec. To study the effect of Relative Humidity (RH) on the evaporation rate, in particular, the present study offers three simulations, all with the same standard room conditions, only differ in relative humidity s 40%, 60%, and 90%. Another source of variability is the cough-expired volume. This study adopts existent experimental work to establish two cough flow rate profiles. The Lagrangian discrete phase model is adopted along with the species model to track and investigate the cough droplet dispersion and evaporation.

Simulation of Airflow and Fuel Spray Through an Axial Swirler for Gas Turbine Applications

2008 ◽  
Author(s):  
Joshua E. Kempenaar ◽  
Kim A. Shollenberger ◽  
Gareth W. Oskam
Keyword(s):  
Gas Turbine ◽  
Cfd Simulation ◽  
Cross Flow ◽  
Fuel Spray ◽  
Fuel Injector ◽  
Discrete Phase Model ◽  
Flow Area ◽  
Jet In Cross Flow ◽  
Discrete Phase ◽  
Break Up

A computational fluid dynamics (CFD) simulation of the effects of an upstream blockage on the fuel spray and airflow through an axial swirler in an experimental gas turbine fuel injector has been conducted. Blockage was varied by means of varying the inside diameter of a restriction upstream of the entrance to the axial swirler. Fuel is injected as a jet in cross-flow through fuel nozzles located in axial swirler vanes. Fuel spray was modeled in the commercial CFD code Fluent 6.3.26 using the Lagrangian approach with the built-in Discrete Phase Model (DPM). Results are given for the TAB, Wave, and KH-RT break-up models. Preliminary simulations with the TAB break-up model were performed for a simple axisymmetric jet and compared to experimental results before simulating the axial swirler geometry. The axial swirler simulations predict that spray dispersion decreases and droplet size increases as the flow area of the blocker ring increases.

scholarly journals Performance Characterization of the UAV Chemical Application Based on CFD Simulation

Agronomy ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 308 ◽  
Author(s):  
Hang Zhu ◽  
Hongze Li ◽  
Cui Zhang ◽  
Junxing Li ◽  
Huihui Zhang
Keyword(s):  
Wind Speed ◽  
Correlation Coefficient ◽  
Cfd Simulation ◽  
Least Square Method ◽  
Least Square ◽  
Universal Method ◽  
Discrete Phase Model ◽  
Chemical Application ◽  
Distance Model ◽  
Discrete Phase

Battery-powered multi-rotor UAVs (Unmanned Aerial Vehicles) have been employed as chemical applicators in agriculture for small fields in China. Major challenges in spraying include reducing the influence of environmental factors and appropriate chemical use. Therefore, the objective of this research was to obtain the law of droplet drift and deposition by CFD (Computational Fluid Dynamics), a universal method to solve the fluid problem using a discretization mathematical method. DPM (Discrete Phase Model) was taken to simulate the motion of droplet particles since it is an appropriate way to simulate discrete phase in flow field and can track particle trajectory. The figure of deposition concentration and trace of droplet drift was obtained by controlling the variables of wind speed, pressure, and spray height. The droplet drifting models influenced by different factors were established by least square method after analysis of drift quantity to get the equation of drift quantity and safe distance. The relationship model, Yi(m), between three dependent variables, wind speed Xw(m s−1), pressure Xp(MPa) and spray height Xh(m), are listed as follows: The edge drift distance model was Y1 = 0.887Xw + 0.550Xp + 1.552Xh − 3.906 and the correlation coefficient (R2) was 0.837; the center drift distance model was Y2 = 0.167Xw + 0.085Xp + 0.308Xh − 0.667 and the correlation coefficient (R2) was 0.774; the overlap width model was Y3 = 0.692xw + 0.529xp + 1.469xh − 3.374 and the correlation coefficient (R2) was 0.795. For the three models, the coefficients of the three variables were all positive, indicating that the three factors were all positively correlated with edge drift distance, center drift distance, and overlap width. The results of this study can provide theoretical support for improving the spray quality of UAV and reducing the drift of droplets.

scholarly journals Effect of Oxygen Content and Temperature On Stabilization of Arsenic in Copper Smelting System

2021 ◽  
Author(s):  
Shenghang Xu ◽  
Bin Hu ◽  
Huibin Zhang ◽  
Min Wu ◽  
Yanan Wang ◽  
...  
Keyword(s):  
Covalent Bond ◽  
Flash Smelting ◽  
Hazardous Substances ◽  
Copper Smelting ◽  
Smelting Process ◽  
Reaction Shaft ◽  
Calcium Arsenate ◽  
Effect Of Oxygen ◽  
Different Content ◽  
Content Of Oxygen

Abstract Arsenic-bearing wastes from copper smelting system are usually disposed by trapping them in slag tailing. However, arsenic in slag tailing is not that stable, which can infiltrate into the groundwater, threatening the environment and human health. The solidification/stabilization (S/S) of arsenic is the only way to deal with arsenic contamination. The flash smelting method shows relatively high S/S ability of arsenic, but the process and mechanism remain unclear. In this paper, we aim at revealing the effect of atmosphere on the S/S process of arsenic owing to the different content of oxygen in reaction shaft and sedimentation tank in copper smelting system. Calcium arsenate, SiO2, Fe2O3 and iron powders were sintered at different temperature in air and argon to simulate the S/S reaction. The results show that the sintering product is Fe-Si oxide in air and fayalite in argon, and the fayalite possesses better capacity to solidify arsenic than that of Fe-Si oxide. The toxicity characteristic leaching procedure (TCLP) results reveal that the leached concentration of arsenic from fayalite fabricated at 1200 ℃ is only 2.916 mg L-1, which satisfies the identification standard for hazardous substances in China. Furthermore, the theoretical calculation reveals that AsO4 and SiO4 tetrahedrons can be connected by O atoms when sintered in argon, and the Si-O-As covalent bond can evidently inhibit the release of As atom from fayalite. This work can not only clarify the S/S mechanism of arsenic in flash smelting process, but also provide theoretical guidances to dispose arsenic-bearing waste harmlessly.

scholarly journals Simulation of un industrial waste treatment tank

2020 ◽  
Vol 9 (4) ◽  
pp. e180942542
Author(s):  
Elcio Fernando Pereira ◽  
Luiz Mário Nelson Gois
Keyword(s):  
Petrochemical Industry ◽  
Cfd Simulation ◽  
Waste Treatment ◽  
Discrete Phase Model ◽  
Depth Data ◽  
Treatment Tank ◽  
Computational Mesh ◽  
Discrete Phase ◽  
Particles Trajectories ◽  
Lagrange Approach

The objective of the present work was to evaluate the operation of an industrial sedimentation tank used in the separation of solid waste from the petrochemical industry. The depth data were obtained through a “interface float”, while the diameters and the positions of the particles through the CFD simulation. The computational fluid dynamics simulator (FLUENT 6.3.26) was used to perform a multiphase simulation using the Euler-Lagrange approach and was used to determine the particles trajectories and cotours of solids accumulated in the bottom of the tank. This allowed a better understanding of solids accumulation and improvement of the cleaning process. In the simulation of the tank a large computational mesh comprising 464,094 computational nodes was designed. The use of the Euler-Lagrange approach meant that a discrete phase model had to be established and the parameters of Rosin-Rammler solids distribtion model for the boundary conditions of the simulation had to be determined. 

Evaluation of Melting Temperature of the Freeze Slag in Reaction Shaft of Flash Smelting Furnace

2011 ◽  
Vol 402 ◽  
pp. 277-282 ◽  
Author(s):  
Jin Liang Wang ◽  
Yan Xin Wu ◽  
Li Wei Liang
Keyword(s):  
Melting Temperature ◽  
Flash Smelting ◽  
Smelting Process ◽  
Reaction Shaft ◽  
Chemical Reagents ◽  
Melting Temperatures ◽  
Ash Melting ◽  
Flash Smelting Furnace ◽  
Operation Characteristics ◽  
Slag Melting

According to the reaction shaft operation characteristics during the flash smelting process, 15 groups of slag samples containing high Fe3O4were prepared by some chemical reagents, and the slag melting temperatures were measured using a ZDHR-200 type intelligent test instrument for ash melting point by means of hemisphere point. Then, the mathematical formula between the melting temperature and the chemical composition of freeze slag were acquired by means of nonlinear regression analysis. The effects of the Fe/SiO2ratio (mFe/mSiO2), CaO/SiO2ratio (mCaO/mSiO2), Fe3O4content (ωFe3O4), Cu2O content (ωCu2O) and MgO content (ωMgO) on the slag melting temperature were also studied. Results show that the melting temperatures calculated by the regression formula reproduce the experimental data in molten freeze slag with high precision. The slag melting temperature ascends rapidly with increasing ωFe3O4when ωFe3O4>18%, and descends quickly when ωCu2Oraises from 3 % to 7 %, but descends slowly with increasing ωMgO. The melting temperature tend to go down first and then rise up with the increase of mFe/mSiO2and mCaO/mSiO2, arriving at the minimum when mFe/mSiO2=1.3 and mCaO/mSiO2=0.8, respectively.

Determination of Surface Tension of the Freeze Slag in Reaction Shaft of Flash Smelting Furnace

2011 ◽  
Vol 402 ◽  
pp. 22-27 ◽  
Author(s):  
Jin Liang Wang ◽  
Yan Xin Wu ◽  
Li Wei Liang
Keyword(s):  
Surface Tension ◽  
Physical Property ◽  
Flash Smelting ◽  
Smelting Process ◽  
Reaction Shaft ◽  
Slag Surface ◽  
Chemical Reagents ◽  
Synthetic Test ◽  
Flash Smelting Furnace ◽  
Chamber Temperature

According to the reaction shaft operation characteristics during the flash smelting process, 15 groups of slag samples containing high Fe3O4were prepared by some chemical reagents, and then the slag surface tensions were measured using a RTW-10 type synthetic test instrument for melt physical property by means of suspension link. The effects of temperature ( T ), basicity ( B ), the Fe/SiO2ratio (mFe/mSiO2), Fe3O4content (ωFe3O4), Cu2O content (ωCu2O), MgO content (ωMgO) and CaO content (ωCaO) on the slag surface tension (δ) were also studied. Results show that δ fluctuate between 0.3N/m to 0.8 N/m, and is increased with the increase of T, B, mFe/mSiO2, ωCu2O, ωMgOand ωCaO, and with the decrease of ωFe3O4, under the range of slag contents: mFe/mSiO21.36~1.78, ωFe3O417.83%~21.18%,ωCu2O3.51%~8.34%,ωMgO2.21%~6.57%,ωCaO6.22%~9.87% and the temperature range of 1380°C to 1500°C. To make the freeze slag adhere to the reaction shaft inner wall easily, the Fe3O4content in freeze slag should be increased and the inner chamber temperature of reaction shaft should be controlled appropriately.

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