Effective diffusivity of moisture in low rank coal during superheated steam drying at atmospheric pressure

• Authors: Zdzisław Pakowski , Robert Adamski , Sławomir Kwapisz
• Languages of publication: EN

Abstracts

EN

The effective diffusivity of water in brown coal of Bełchatów mine was experimentally determined. The experiments were performed in superheated steam at 200°C and atmospheric pressure using slightly compressed pellets of cylindrical shape. The drying and temperature curves of the sample were used to identify diffusivity. An inverse problem was formulated and solved by the finite element method for 3D axially symmetric cylindrical geometry of the sample. A satisfactory fit of the simulated curves to experimental results was obtained. The obtained dependence of effective diffusivity on moisture content and temperature may be used in designing lignite dryers.

Keywords

EN

diffusion; moisture; lignite

• Publisher: De Gruyter Open
• Journal: Chemical and Process Engineering
• Year: 2012
• Volume: 33
• Issue: 1
• Pages: 43-51

Dates

published

1 - 3 - 2012

online

6 - 3 - 2012

Contributors

author

Zdzisław Pakowski

• Faculty of Process and Environmental Engineering, Technical University of Lodz, ul. Wólczańska 213, 90-924 Łódź, Poland

author

Robert Adamski

• Faculty of Process and Environmental Engineering, Technical University of Lodz, ul. Wólczańska 213, 90-924 Łódź, Poland

author

Sławomir Kwapisz

• Faculty of Process and Environmental Engineering, Technical University of Lodz, ul. Wólczańska 213, 90-924 Łódź, Poland

References

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Identifiers

DOI

10.2478/v10176-012-0004-3