Effect of hydrodynamic conditions of the kinetics of Bentonite Suspension Flocculation by Cationic Polyelectrolytes and the strength of formed flocs

2010 ◽  
Vol 72 (3) ◽  
pp. 409-416 ◽  
Author(s):  
R. Meszaros ◽  
S. Barany ◽  
I. Solomentseva
Keyword(s):  
Hydrodynamic Conditions ◽  
Bentonite Suspension ◽  
Kinetics Of ◽  
Cationic Polyelectrolytes

The Study of the Kinetics of Obtaining Betulin and Extractive Substances from the Birch Tree Bark

2017 ◽  
Vol 29 ◽  
pp. 42-47
Author(s):  
Sergei I. Tretiakov ◽  
Elena N. Koptelova ◽  
Natalia A. Kutakova ◽  
Nina V. Bagretsova ◽  
Nadezhda L. Voropaeva
Keyword(s):  
Tree Bark ◽  
Birch Bark ◽  
Hydrodynamic Conditions ◽  
Food Industries ◽  
Plywood Industry ◽  
Birch Tree ◽  
Extractive Substances ◽  
Bioactive Agents ◽  
The Given ◽  
Kinetics Of

Birch bark attracts attention of researchers as a source of betulin and other extractive substances (ES) useful for chemical, pharmaceutical and food industries. A challenge is to develop an efficient way of obtaining these bioactive agents. This paper presents a microwave-assisted technique of extracting these substances from the waste birch bark of the plywood industry. The kinetics of the extraction was investigated. With the process going on in the pore-diffusion area, the hydrodynamic conditions of the operation are discussed. An algorithm for calculating the kinetics of the procedure was developed and experimentally confirmed. The estimations for the process were made at constant values of the internal diffusion coefficient. The value of the coefficient was found to be a function of the birch bark fragments dimensions. An equation was established to estimate the duration of the extraction to obtain the given yield of ES and betulin.

scholarly journals OPTIMALIZATION OF PHOTOREACTOR GEOMETRY FOR THE CULTIVATION OF CHLAMYDOMONAS REINHARDTII

2018 ◽  
Vol 58 (2) ◽  
pp. 92
Author(s):  
Roman Fekete ◽  
Terézia Žáková ◽  
Ľudmila Gabrišová ◽  
Peter Kotora ◽  
Peter Peciar ◽  
...  
Keyword(s):  
Growth Rate ◽  
Chlamydomonas Reinhardtii ◽  
Biomass Yield ◽  
Scale Up ◽  
Model Organism ◽  
Biomass Growth ◽  
Hydrodynamic Conditions ◽  
Optimal Conditions ◽  
Optimal Ratio ◽  
Kinetics Of

At the present time, a great attention is being paid to the use of algae. Algae can adapt to different conditions and can produce substances corresponding to responsible environments. The main problem in their cultivation is the design of a suitable photoreactor. It should create the optimal conditions for their growth, which is mainly dependent on the contact of the algae with the light. The intensity of the light depends on the hydrodynamic conditions in the photoreactor and on its geometry. This paper deals with the study of kinetics of growth and gross biomass yield of biomass in laboratory photobioreactors, respecting their geometrical similarity as a basis for a possible scale-up. An optimal ratio between biomass growth rate and its gross biomass yield as a function of the photoreactor geometry is searched. <em>Chlamydomonas reinhardtii</em> were used as the model organism.

scholarly journals Numerical Investigation of the Hydrodynamic Conditions in A Multi-Strand Cc Tundish with Closed Outlets

2014 ◽  
Vol 59 (3) ◽  
pp. 887-892 ◽  
Author(s):  
T. Merder
Keyword(s):  
Liquid Steel ◽  
Stokes Equations ◽  
Thermal Conditions ◽  
Casting Process ◽  
Navier Stokes ◽  
Hydrodynamic Conditions ◽  
Continuous Casting Process ◽  
Navier Stokes Equations ◽  
Steel Flow ◽  
Kinetics Of

Abstract In industrial conditions there are situations when the CC machine works under emergency. It can be result of mechanical or electrical causes, breakout of billet or problem with supplying new parts of liquid steel to the CC machine. As a consequence one or two outlets of the tundish should be closed. However, closing one of the outlets influences the hydrodynamic and thermal conditions occurring in the tundish. Thus, the important information is which of the outlets should be closed to conduct further continuous casting process correctly.The following research was conducted to analyze the influence of liquid steel flow behaviour in the multi-strand tundish when all outlets do not work. Such problem was solved by means of numerical methods based on Navier-Stokes equations (k–ɛ standard turbulence model). Numerical simulations were done using the educational version of CFD program (Computational Fluid Dynamics) – ANSYSFluent. As a result forecasted velocity fields and RTD curves (Residence Time Distribution) were obtained. RTD characteristics were used to determine kinetics of liquid steel mixing and also to calculate parts of particular flow areas for studied cases.

scholarly journals Development of Software for Calculating of the Vortex Fluidized Bed Granulator

2017 ◽  
Vol 2 (1) ◽  
pp. 1-10
Author(s):  
Artem Artyukhov ◽  
Viktor Obodiak ◽  
Pavlo Boiko
Keyword(s):  
Mathematical Model ◽  
Fluidized Bed ◽  
Residence Time ◽  
Vortex Flow ◽  
Hydrodynamic Conditions ◽  
Kinetic Characteristics ◽  
Separation Processes ◽  
Granulation Process ◽  
Optimization Calculation ◽  
Kinetics Of

The article is devoted to the development of software for calculating the hydrodynamic conditions and kinetic characteristics of granulation process in vortex devices. In the basis software Vortex Granulator© and Classification in vortex flow© original mathematical model for calculating the flow rate of gas and granules classification and separation processes of granules in a vortex granulator, kinetics of granules heating and removing moisture from the granules was put. The structure of software and algorithm of their work is shown. In the article, an algorithm for calculation of the granulation process in the vortex granulator using the developed software is shown. Software designed in JavaFx platform. Vortex Granulator© and Classification in vortex flow© allow to conduct an optimization calculation of vortex granulator according the criteria of minimum required residence time of granules in device workspace.

scholarly journals Influence of Hydrodynamic Conditions on Precipitation Kinetics of Barium Sulfate in a Multifunctional Reactor

Processes ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 146
Author(s):  
Agata Małysiak ◽  
Tomasz Walica ◽  
Tomasz Fronczyk ◽  
Marcin Lemanowicz
Keyword(s):  
Reynolds Number ◽  
Kinetic Parameters ◽  
Flow Pattern ◽  
Barium Sulfate ◽  
Turbulent Regime ◽  
Hydrodynamic Conditions ◽  
Precipitation Kinetics ◽  
Mixed Product ◽  
Multifunctional Reactor ◽  
Kinetics Of

In this paper, the influence of hydrodynamic conditions in Kenics static mixer, which acts as a multifunctional reactor, on precipitation kinetics of barium sulfate is investigated. The investigated range of the Reynolds number varied between 500 and 5000, which covered both laminar and turbulent flow regimes. In all experiments, the relative supersaturation was maintained at the constant level (s = 205). The obtained precipitate was collected and used for crystal size distribution (CSD) determination. On that basis, the kinetic parameters of the process were calculated using the mixed suspension mixed product removal (MSMPR) mathematical model of the process. It was found that for the whole investigated range of Reynolds number, the mixing conditions were satisfactory. CSD analysis showed that in the laminar regime, a clear tendency in crystal behavior could not be noticed. However, during the analysis of the turbulent regime, the presence of a critical Reynolds number was noticed. Above this value, there is a change in the flow pattern, which results in a change of kinetic parameters (B, G), as well as manifests in a form of a decrease in the value of mean diameters of crystals. The flow pattern change is caused by the geometry of the reactor’s inserts.

The Influence of the Shape of Turbulence Inhibitors on the Hydrodynamic Conditions Occuring in a Tundish

2013 ◽  
Vol 58 (4) ◽  
pp. 1111-1117 ◽  
Author(s):  
T. Merder
Keyword(s):  
Time Distribution ◽  
Residence Time Distribution ◽  
Concentration Distribution ◽  
Water Model ◽  
Hydrodynamic Conditions ◽  
Working Space ◽  
Transient Zone ◽  
Turbulence Inhibitor ◽  
The Impact ◽  
Kinetics Of

Abstract The article presents results of the research that was carried out taking into account the influence of the (impact pads) turbulence inhibitor geometry and its equipment of the working space on the hydrodynamic conditions occurring in T-type tundish. Four different turbulence inhibitors were discussed. They differ in shape and configuration of external walls. The research was conducted basing on the numerical simulations as well as on tests performed on physical water model. As a result of calculations the velocity field distribution, turbulence field and marker concentration distribution in the liquid steel for the tested geometrical variants of turbulence inhibitors were obtained. Worked out RTD curves (Residence Time Distribution) allowed to determine the kinetics of steel mixing (the range of transient zone was estimated), and the percentage participation of the particular flow zones. The test carried out on the water model concerned one of the tested turbulence inhibitors. Research was done to verify the parameter settings of the numerical model applied in calculations. Obtained results gave valuable information about the work of the object after applying different turbulence inhibitors.

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