Axial Dispersion Based on the Residence Time Distribution Curves in a Millireactor Filled with β-SiC Foam Catalyst

2012 ◽  
Vol 51 (46) ◽  
pp. 15011-15017 ◽  
Author(s):  
Meryem Saber ◽  
Cuong Pham-Huu ◽  
David Edouard
Keyword(s):  
Residence Time ◽  
Time Distribution ◽  
Residence Time Distribution ◽  
Axial Dispersion

Analysis Of Residence Time Distribution Of Fluid Flow By Axial Dispersion Model

2010 ◽  
Author(s):  
Sugiharto ◽  
Zaki Su’ud ◽  
Rizal Kurniadi ◽  
Abdul Waris ◽  
Zainal Abidin ◽  
...  
Keyword(s):  
Fluid Flow ◽  
Residence Time ◽  
Time Distribution ◽  
Residence Time Distribution ◽  
Dispersion Model ◽  
Axial Dispersion ◽  
Axial Dispersion Model

scholarly journals Residence time distribution and flow pattern modeling of oilseeds in a pilot screw press

OCL ◽  
2020 ◽  
Vol 27 ◽  
pp. 65
Author(s):  
Laurine Bogaert ◽  
Houcine Mhemdi ◽  
Eugène Vorobiev
Keyword(s):  
Residence Time ◽  
Time Distribution ◽  
Residence Time Distribution ◽  
Rotation Speed ◽  
Screw Press ◽  
Operating Conditions ◽  
Axial Dispersion ◽  
Experimental Methodology ◽  
Theoretical Approaches ◽  
The Press

Mechanical expression is widely applied for oil recovery from oilseeds using continuous screw presses. Despite significant recent advances in the field of press design and automation, it remains difficult to predict the press performances based on the theoretical approaches, and more experimental investigations are needed to clarify and characterize the seeds flow and expression behavior in the press. Residence Time Distribution (RTD) is a frequently used tool in chemical engineering to characterize the material flow by simple tracer tests. In this paper, we explore the feasibility of using RTD for the screw presses, in order to check the flow patterns homogeneity and identify the possible deviations depending on the press geometry and the operating conditions. Both theoretical modeling and experimental investigation are conducted for two different screw press designs (Reinartz and Olexa), and at the different rotation speeds. An original and reliable experimental methodology was developed by using erucic acid as tracer in the form of pulse injection and gas chromatography as detection method. Experimental results coupled with statistical calculations showed the influence of the screw geometry and the rotation speed on the seeds flow inside the press. The matter displacement was much faster and the experimental residence time was very close to the theoretical one indicating more homogeneity and less dispersion in the Olexa arrangement in comparison to the Reinartz arrangement. The higher variance observed at lower rotation speed (2.4 rpm) suggested the presence of flow defects like mixing and axial dispersion in the press. To complete the experimental work, axial dispersion model was applied, and allowed obtaining the valuable information, such as axial dispersion degree and distribution functions. Obtained results can be very useful to predict the performance of existing screw presses and design more efficient industrial equipments.

Modeling and Hydraulic Characterization of a Filter-Press-Type Electrochemical Reactor by Using Residence Time Distribution Analysis and Hydraulic Indices

2018 ◽  
Vol 16 (10) ◽  
Author(s):  
Alejandro Regalado-Méndez ◽  
Juan Mentado-Morales ◽  
Carlos Estrada Vázquez ◽  
Gerardo Martínez-Villa ◽  
Mario E. Cordero ◽  
...  
Keyword(s):  
Residence Time ◽  
Time Distribution ◽  
Residence Time Distribution ◽  
Plug Flow ◽  
Electrochemical Reactor ◽  
Filter Press ◽  
Axial Dispersion ◽  
Hydraulic Efficiency ◽  
Volume Percent

Abstract Modeling and hydraulic characterization of a filter-press-type electrochemical reactor was studied by means of residence time distribution and hydraulic indices. For these purposes, a theoretical and approximation of residence time distribution experimental curves with axial dispersion model and Danckwerts’ boundary conditions, the Morrill dispersion index, the short-circuiting index, the Morrill volumetric efficiency index, and useful volume percent were used in order to establish deviation from plug-flow ideal, as well as dead volume, and the hydraulic efficiency. The hydraulic efficiency measure of the filter-press-type electrochemical reactor confirms uniformity of flow and a highly effective useful volume percent (91 %-98 % for all liquid flow rates tested). The axial dispersion coefficients computed (0.0005–0.0021 m2/s) indicates a small deviation of plug-flow ideal. Hence, the plug-flow reactor model is reliable for purpose modeling of the filter-press-type electrochemical reactor used in this research. Furthermore, hydrodynamic characterization of the tested filter-press-type electrochemical reactor by using hydraulic indices demonstrated its suitability for several electrochemical applications.

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