In this work the influence of turbulent mixing on the course of two parallel chemical reactions (... more In this work the influence of turbulent mixing on the course of two parallel chemical reactions (neutralization of sodium hydroxide and hydrolysis of ethyl chloroacetate) is investigated for a process carried out in a semibatch stirred tank reactor. The multi-scale nature of the process is highlighted by a time-scale analysis of controlling process mechanisms. Two reactive mixing models of different complexity, both accounting for all relevant phenomena from the micro- to the macroscale, are applied for the simulation of the process. Computational results of both models for various operating conditions are compared with experimental data, thus highlighting the strengths of the two models.
A precipitation process is considered in which completely miscible solution and supercritical ant... more A precipitation process is considered in which completely miscible solution and supercritical antisolvent are passed through premixing and diluting zones of a turbulent flow. The influence of flow velocity on particle size and nuclei concentration is discussed in terms of mixing and precipitationtime constants and their supersaturation dependencies. The proposed model allowed the major process parameters such as supersaturation profile, mixed fluid fraction and mean particle size to be calculated and compared with experimental data. For the crystallization system paracetamol/ethanol/CO2 studied, the supersaturation profile becomes established at Re≅104. The particle size and shape are defined, firstly, by increase of supersaturation and relative volume of mixed (on molecular scale) fluid with increase of flow velocity and, secondly, by decrease of residence time available for nucleation with increase of flow velocity. These competitive processes can result in minimum particle size at a defined flow rate.
... 6. Flesch JC, Spicer PT, Pratsinis SE (1999) Laminar and turbulent shear-induced flocculatio... more ... 6. Flesch JC, Spicer PT, Pratsinis SE (1999) Laminar and turbulent shear-induced flocculation of fractal aggregates, AIChE J. 45, 11141124 7. Soos M., Moussa AS, Ehrl L., Sefcik J., Wu H. Morbidelli M., Effect of shear rate on aggregate size and morphology investigated ...
Effects of hydrodynamic turbulent stress on disintegration of plant cell aggregates Rhodiola rose... more Effects of hydrodynamic turbulent stress on disintegration of plant cell aggregates Rhodiola rosea L.(Crassulaceae) were investigated. Investigations were carried out in the stirred tank mixer equipped with the Rushton type turbine mixer and four baffles under conditions when breakage of cell aggregates dominates the process. Breakage process was interpreted with the multifractal model of turbulence.
In this work the influence of turbulent mixing on the course of two parallel chemical reactions (... more In this work the influence of turbulent mixing on the course of two parallel chemical reactions (neutralization of sodium hydroxide and hydrolysis of ethyl chloroacetate) is investigated for a process carried out in a semibatch stirred tank reactor. The multi-scale nature of the process is highlighted by a time-scale analysis of controlling process mechanisms. Two reactive mixing models of different complexity, both accounting for all relevant phenomena from the micro- to the macroscale, are applied for the simulation of the process. Computational results of both models for various operating conditions are compared with experimental data, thus highlighting the strengths of the two models.
A precipitation process is considered in which completely miscible solution and supercritical ant... more A precipitation process is considered in which completely miscible solution and supercritical antisolvent are passed through premixing and diluting zones of a turbulent flow. The influence of flow velocity on particle size and nuclei concentration is discussed in terms of mixing and precipitationtime constants and their supersaturation dependencies. The proposed model allowed the major process parameters such as supersaturation profile, mixed fluid fraction and mean particle size to be calculated and compared with experimental data. For the crystallization system paracetamol/ethanol/CO2 studied, the supersaturation profile becomes established at Re≅104. The particle size and shape are defined, firstly, by increase of supersaturation and relative volume of mixed (on molecular scale) fluid with increase of flow velocity and, secondly, by decrease of residence time available for nucleation with increase of flow velocity. These competitive processes can result in minimum particle size at a defined flow rate.
... 6. Flesch JC, Spicer PT, Pratsinis SE (1999) Laminar and turbulent shear-induced flocculatio... more ... 6. Flesch JC, Spicer PT, Pratsinis SE (1999) Laminar and turbulent shear-induced flocculation of fractal aggregates, AIChE J. 45, 11141124 7. Soos M., Moussa AS, Ehrl L., Sefcik J., Wu H. Morbidelli M., Effect of shear rate on aggregate size and morphology investigated ...
Effects of hydrodynamic turbulent stress on disintegration of plant cell aggregates Rhodiola rose... more Effects of hydrodynamic turbulent stress on disintegration of plant cell aggregates Rhodiola rosea L.(Crassulaceae) were investigated. Investigations were carried out in the stirred tank mixer equipped with the Rushton type turbine mixer and four baffles under conditions when breakage of cell aggregates dominates the process. Breakage process was interpreted with the multifractal model of turbulence.
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Papers by Jerzy Baldyga