Simulation of flow field characteristics in scheelite leaching tank with H2SO4–H3PO4

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Jiangtao Li ◽  
Guoxiang Cao ◽  
Zhongyang Tang ◽  
Zhongwei Zhao
Keyword(s):  
Calcium Sulfate ◽  
Low Cost ◽  
Flow Characteristics ◽  
Solid Particles ◽  
Stirred Tank ◽  
Environment Friendly ◽  
Mixed Acid ◽  
Solid Suspension ◽  
Flow Field Characteristics ◽  
Good Environment

Abstract Digesting scheelite by using H2SO4–H3PO4 is an environment-friendly and low-cost technology. The key approach to achieving efficient scheelite decomposition involves providing a good environment with uniform material composition for the growth of calcium sulfate. Therefore, numerical simulation of gypsum particle suspensions in a square stirred tank with a frame-type agitator for leaching scheelite was investigated. Simulated optimized results showed that the homogeneity of a multiphase flow system increased with the speed of the agitator. Reducing off-bottom clearance eased the dispersion of gypsum into the liquid. Adding baffles increased turbulence intensity and axial velocity in the tank, which eased solid suspension. The suspension improved, together with increases in the torque and power requirements of the agitator when the speed changed and baffled were added. However, when the solid suspension improved, the stirring torque and power slightly decreased, under a different off-bottom clearance of the agitator. Meanwhile, with residence time distribution as an evaluation criterion, the experimental results verified that the flow characteristics of the solid particles improved after optimization. This study can provide a theoretical basis and guidance for the optimization of the design and enlargement test of the stirred tank for leaching scheelite with sulfuric–phosphorous mixed acid.

CFD Simulation of Solid Suspension in a Stirred Reactor Driven by a Dual Punched Rigid-Flexible Impeller

2018 ◽  
Vol 16 (5) ◽  
Author(s):  
Deyin Gu ◽  
Zuohua Liu ◽  
Facheng Qiu ◽  
Jun Li ◽  
Changyuan Tao ◽  
...  
Keyword(s):  
Reference Frames ◽  
Cfd Simulation ◽  
Energy Dissipation Rate ◽  
Solid Particles ◽  
Stirred Tank ◽  
Two Phase ◽  
Stirred Reactor ◽  
Solid Suspension ◽  
Computational Fluid Dynamics Cfd ◽  
Solid Liquid

Abstract Solid suspension characteristics were predicted by computational fluid dynamics (CFD) simulation in a stirred tank driven by a dual rigid-flexible impeller and a dual punched rigid-flexible impeller. An Eulerian-Eulerian approach, standard k-ε turbulence model, and multiple reference frames (MRF) technique were employed to simulate the solid-liquid two-phase flow, turbulent flow, and impeller rotation in the stirred tank, respectively. The CFD results showed that dual punched rigid-flexible impeller could increase the axial velocity and turbulent kinetic energy dissipation rate, and decrease the quantity of sediment solid particles compared with dual rigid-flexible impeller. Less impeller power was consumed by dual punched rigid-flexible impeller compared with dual rigid-flexible impeller at the same impeller speed. It was found that punched rigid-flexible impeller was more efficient in terms of solid suspension quality than dual rigid-flexible impeller at the same Pw. The simulated results for the axial solid concentration were in good agreement with the experimental data.

Mass Transport Modelling in Porous Media Using Delay Differential Equations

2006 ◽  
Vol 258-260 ◽  
pp. 586-591
Author(s):  
António Martins ◽  
Paulo Laranjeira ◽  
Madalena Dias ◽  
José Lopes
Keyword(s):  
Porous Media ◽  
Differential Equations ◽  
Mass Transport ◽  
Delay Differential Equations ◽  
Dispersion Model ◽  
Flow Characteristics ◽  
Convective Transport ◽  
Transport Modelling ◽  
Flow Field Characteristics ◽  
Delay Differential

In this work the application of delay differential equations to the modelling of mass transport in porous media, where the convective transport of mass, is presented and discussed. The differences and advantages when compared with the Dispersion Model are highlighted. Using simplified models of the local structure of a porous media, in particular a network model made up by combining two different types of network elements, channels and chambers, the mass transport under transient conditions is described and related to the local geometrical characteristics. The delay differential equations system that describe the flow, arise from the combination of the mass balance equations for both the network elements, and after taking into account their flow characteristics. The solution is obtained using a time marching method, and the results show that the model is capable of describing the qualitative behaviour observed experimentally, allowing the analysis of the influence of the local geometrical and flow field characteristics on the mass transport.

scholarly journals Evaluating Simple Methodology for Piezoelectric Level Sensors Protection

Proceedings ◽  
2019 ◽  
Vol 48 (1) ◽  
pp. 30
Author(s):  
Luis Hamilton Pospissil Garbossa ◽  
Argeu Vanz ◽  
Matias Guilherme Boll ◽  
Hamilton Justino Vieira
Keyword(s):  
Water Level ◽  
Flood Control ◽  
Low Cost ◽  
Solid Particles ◽  
Storm Events ◽  
Sewer Systems ◽  
Continuous Monitor ◽  
Level Monitoring ◽  
Water Level Monitoring

The increasing frequency of extreme storm events has implications for the operation of sewer systems, storm water, flood control monitoring and tide level variations. Accurate and continuous monitor water level monitoring is demanded in different environments. Piezoelectric sensors are widely used for water level monitoring and work submerged in waters subject to the presence of solid particles, biological fouling and saltwater oxidation. This work aimed to develop a simple, low-cost methodology to protect sensors over long-term deployment. The results show that simple actions, costing less than 2 EUR, can protect and extend the lifecycle of equipment worth over 2000 EUR, ensuring continuous monitoring and maintaining quality measurements.

Self-reducible copper ion complex ink for air sinterable conductive electrodes

2016 ◽  
Vol 4 (45) ◽  
pp. 10740-10746 ◽  
Author(s):  
Sanghun Cho ◽  
Zhenxing Yin ◽  
Yong-keon Ahn ◽  
Yuanzhe Piao ◽  
Jeeyoung Yoo ◽  
...  
Keyword(s):  
Low Cost ◽  
Copper Ion ◽  
Environment Friendly

We introduce a novel self-reducible Cu ion complex ink, composed of formate, alkanolamine groups and poly alcohols, for the air sinterable, low-cost, environment-friendly fabrication of Cu conductive electrodes.

Fabrication of hydrophobic NiFe2O4@poly(DVB-LMA) sponge via Pickering emulsion template method for oil/water separation

Soft Matter ◽  
2021 ◽  
Author(s):  
Caimei Zhao ◽  
Lei Chen ◽  
Chuanming Yu ◽  
Binghua Hu ◽  
Haoxuan Huang ◽  
...  
Keyword(s):  
Oil Spills ◽  
Low Cost ◽  
Pickering Emulsion ◽  
Template Method ◽  
Water Separation ◽  
Environment Friendly ◽  
Oil Water Separation ◽  
Oil Water ◽  
Cost Efficient

Super-hydrophobic porous absorbent is a convenient, low-cost, efficient and environment-friendly material in the treatment of oil spills. In this work, a simple Pickering emulsion template method was employed to fabricate...

scholarly journals Recovery of FTO coated glass substrate via environment-friendly facile recycling perovskite solar cells

RSC Advances ◽  
2021 ◽  
Vol 11 (24) ◽  
pp. 14534-14541
Author(s):  
M. S. Chowdhury ◽  
Kazi Sajedur Rahman ◽  
Vidhya Selvanathan ◽  
A. K. Mahmud Hasan ◽  
M. S. Jamal ◽  
...  
Keyword(s):  
Solar Cells ◽  
Glass Substrate ◽  
Large Scale ◽  
Low Cost ◽  
Perovskite Solar Cells ◽  
Potential Candidate ◽  
Photovoltaic Devices ◽  
Coated Glass Substrate ◽  
Environment Friendly ◽  
Coated Glass

Organic–inorganic perovskite solar cells (PSCs) have recently emerged as a potential candidate for large-scale and low-cost photovoltaic devices.

Environment-Friendly Design of Lithium Batteries Starting from Biopolymer-Based Electrolyte

NANO ◽  
2021 ◽  
pp. 2130006
Author(s):  
Jiayuan Shi ◽  
Bin Shi
Keyword(s):  
Lithium Batteries ◽  
Lithium Battery ◽  
Water Solubility ◽  
Low Cost ◽  
Organic Liquid ◽  
Adhesive Property ◽  
Environment Friendly ◽  
Battery Materials ◽  
Mild Conditions ◽  
Film Forming

The nondegradable nature and toxicity of organic liquid electrolytes reveal the design deficiency of lithium batteries in environmental protection. Biopolymers can be extracted from biomass under mild conditions, thus they are usually low cost and renewable. The unique characteristics of biopolymers such as water solubility, film-forming capability and adhesive property are of importance for lithium battery. The studies on the biopolymer materials for lithium batteries have been reviewed in this work. Although a lot of work on the biopolymer-based battery materials has been reported, it is still a challenge in the design of lithium battery with zero pollution and zero waste.

scholarly journals Two-Phase Dusty Fluid Flow Along a Rotating Axisymmetric Round-Nosed Body

2017 ◽  
Vol 139 (8) ◽  
Author(s):  
Sadia Siddiqa ◽  
Naheed Begum ◽  
M. A. Hossain ◽  
Rama Subba Reddy Gorla
Keyword(s):  
Boundary Layer ◽  
Flow Characteristics ◽  
Leading Edge ◽  
Solid Particles ◽  
Dust Particles ◽  
Computational Domain ◽  
Two Phase ◽  
Carrier Fluid ◽  
Boundary Layer Equations ◽  
Implicit Finite Difference

This article is concerned with the class of solutions of gas boundary layer containing uniform, spherical solid particles over the surface of rotating axisymmetric round-nosed body. By using the method of transformed coordinates, the boundary layer equations for two-phase flow are mapped into a regular and stationary computational domain and then solved numerically by using implicit finite difference method. In this study, a rotating hemisphere is used as a particular example to elucidate the heat transfer mechanism near the surface of round-nosed bodies. We will investigate whether the presence of dust particles in carrier fluid disturbs the flow characteristics associated with rotating hemisphere or not. A comprehensive parametric analysis is presented to show the influence of the particle loading, the buoyancy ratio parameter, and the surface of rotating hemisphere on the numerical findings. In the absence of dust particles, the results are graphically compared with existing data in the open literature, and an excellent agreement has been found. It is noted that the concentration of dust particles’ parameter, Dρ, strongly influences the heat transport rate near the leading edge.

Sign in / Sign up

Export Citation Format

Share Document