09 (2003) Scientific papers, Series Ahttps://hdl.handle.net/10195/381192024-03-29T06:58:10Z2024-03-29T06:58:10ZWall shear stress at the membrane surface and at the surface of plexiglasVelikovská, Pavlínal|Mikulášek, Petrl|Legentilhomme, Patrickl|Comiti, Jacquesl|Jaouen, Pascalhttps://hdl.handle.net/10195/327582021-02-19T07:44:48Z2004-01-01T00:00:00ZWall shear stress at the membrane surface and at the surface of plexiglas
Velikovská, Pavlínal|Mikulášek, Petrl|Legentilhomme, Patrickl|Comiti, Jacquesl|Jaouen, Pascal
The wall shear stress is determined at the surface of a plane ceramic ultrafiltration membrane and at the plate of Plexiglas in a tangential ultrafiltration module. In a first time, the shear stresses are determined at the surface of a plate of Plexiglas mimicking a membrane and at the plane membrane surface without fouling particles with the aim to investigate the influence of permeation. In the second time, the wall shear stress is determined at the surfaceof the plane membrane during the ultrafiltration of spherical no compressible particles suspension inducting a deposit at the membrane surface. In order to study the influence of the concentration of the particles, two concentrations of particles were used for the experiments. The values of the mean wall shear stress and its fluctuations (turbulent intensity rate) were measured by using an electrochemical method. 20 microelectrodes, on which an electrochemical reaction occurs, are mounted flush to the plate of Plexiglas and to the surface of the membrane to determine the maps of shear stress and turbulent intesity rate for two inlet/outlet distributors' configurations.
2004-01-01T00:00:00ZModelling the cake filtration on a rotary Nutsche in oscillatory modeMachač, IvanŠiška, BedřichMachačová, LudmilaDoleček, Petrhttps://hdl.handle.net/10195/327452021-02-19T07:45:31Z2004-01-01T00:00:00ZModelling the cake filtration on a rotary Nutsche in oscillatory mode
Machač, Ivan; Šiška, Bedřich; Machačová, Ludmila; Doleček, Petr
As an alternative to a classical Nutsche with a flat filtration surface, a rotary Nutsche has been developed. It is constructed like a circular drum with the bottom half being used as the filter area. The drum is placed on wheels and simple rope drive enables the drum to oscillate. During a batch filtration period, the filter area of RN filter decreases and equations of filtration taking into account the variability of filter face area should be used for the prediction of rotary Nutsche filtering performance. Such equations for filtration in the static (non-oscillatory) mode have been presented earlier. Herein, the model modified for filtration in an oscillatory mode is presented and the results of its numerical solution for filtration of diatomite and cellulose suspensions are compared with those obtained in testing the filtering ability of a pilot plant cylindrical rotary Nutsche.
2004-01-01T00:00:00ZConditions for implementation of logistics into companies of chemical industry in Czech RepublicVlčková, Vladimírahttps://hdl.handle.net/10195/327432021-02-19T07:46:07Z2004-01-01T00:00:00ZConditions for implementation of logistics into companies of chemical industry in Czech Republic
Vlčková, Vladimíra
Status quo in implementation of logistics into companies of chemical industry in the Czech Republic is presented. The reasons that inhibit quicker assertion of logistics into these companies are discussed. Recommendations for a successful implementation of logistic system are given. Unfinished privatization and the therewith related frequent changes in ownership on this branch of industry was identified as the most significant problem.
2004-01-01T00:00:00ZImplementation of environmental management systems in the Czech RepublicHyršlová, JaroslavaBöhmová, Simonahttps://hdl.handle.net/10195/327422021-02-19T07:46:44Z2004-01-01T00:00:00ZImplementation of environmental management systems in the Czech Republic
Hyršlová, Jaroslava; Böhmová, Simona
The paper deals with the present situation of the implementation of environmental management systems in the Czech republic. It focuses on the main reasons of EMS implementation in companies, on the costs connected with implementation as well as on the actual economic effects of environmental management systems. The objective of this paper is to point out the present standard of environmental costs tracking in those of Czech companies who have implemented environmental management systems and to stress the importance of such information for company management. The paper includes some of the results acquired from the grant-subsidized project of the Grant Agency of the Czech Republic "Environmental Costs Information for Environmental Management" (No. 402/02/0092).
2004-01-01T00:00:00Z