bulk-online, the Powder/Bulk Portal

1971-75 studies Process Engineering Systems,
1982 PhD-theses: Investigations on Flow Behaviour of Moist Soluble Bulk Materials, Bergakademie Freiberg
1991 Sc.D.-theses: Modelling the Flow Behavior of Bulk Materials on Particle Interaction Forces Basis and Application in Bunker Plant Design, TU Bergakademie Freiberg
since 1994 chair for Mechanical Process Engineering at Otto-von-Guericke-University Magdeburg

Know-how and experience:
particle and powder mechanics,
fundamentals of mechanics of particulate solids,
particle and powder testing including
shear cell measurements, granulometry and porosimetry
hopper design for reliable flow, silo pressure calculations, conveyor design for reliable flow,
design of bulk solids handling equipment,
lab- and pilot-scale equipment for: comminution, particle separation, classification, sorting, cake and membrane filtration, high pressure filtration, cake strength testing
crystallisation and precipitation,
particle processing and plant design,
nanoparticle technology,
environmental protection engineering,
material recycling,

Publications:
Tomas, J.: Zum Verfestigungsprozeß von Schüttgütern - Mikroprozesse, Kinetik-modelle und Anwendungen, Schüttguttechnik 2 (1996) 1, 31-51
Lychatz, B., Kruschke, E., Holzhey, W., Kretschmer, H., Tomas, J. und D. Janke:Entschwefelung von Roheisen mit Weichbranntkalk, Stahl und Eisen 116 (1996) 12, 93-101
Tomas, J.: Zum Verfestigungsprozeß von Schüttgütern - Mikroprozesse, Kinetik-modelle und Anwendungen, Chem.- Ing.- Technik 69 (1997) 4, 45-467
Mihlbacher, K., Kollmann, Th., Seidel-Morgenstern, A., Tomas, J. and G. Guichon:Measurement of the degree of internal friction of two native silica packing materialsJ. Chromatogr. A, 818 (1998), 155-168
Tomas, J., Schreier, M., T. Gröger and S. Ehlers: Impact crushing of concrete for liberation and recycling, Powder Technology 105 (1999), 39-51
Tomas, J.: Particle Adhesion Fundamentals and Bulk Material Consolidation, Fine Powder Processing ’99, Pennsylvania State University, 352-365, State College 1999
Kollmann, Th. and J. Tomas: On the Vibrational Flow of Fine Powders, Fine Powder Processing ’99, Pennsylvania State University, 344-351, State College 1999
Schreier, M., Gröger, T., Ehlers, S. u. J. Tomas: Aufschlußzerkleinerung von Beton infolge Prallbeanspruchung, Aufbereitungs-Technik 40 (1999) 5, 232-241
Tomas, J. und T. Gröger: Mehrstufige turbulente Aerosortierung von Bauschutt Aufbereitungs-Technik 40 (1999) 8, 379-386
Gröger, T. and J. Tomas: Assessment of multistage turbulent cross-flow aerosepara-tion of building rubble, XXI International Mineral Processing Congress, Proceedings Vol. C, C7-34 bis C7-43, Rom 2000
Schreier, M. and J. Tomas: Liberation of a particle-composite material, XXI Interna-tional Mineral Processing Congress, Proceedings Vol. A, A2-24 bis A2-35, Rom 2000
Tomas, J.: Particle Adhesion Fundamentals and Powder Flow Behaviour, 3rd Israeli Conference for Conveying and Handling of Particulate Solids, Proceedings Vol. 1, 3.57 - 3.65, The Dead Sea 2000
Kollmann, Th. and J. Tomas: On the Vibrational Flow of Fine Powders, 3rd Israeli Conference for Conveying and Handling of Particulate Solids, Proceedings Vol. 1, 3.66 - 3.72, The Dead Sea 2000
Tomas, J., Gröger, T. and M. Schreier: Liberation and separation of valuables from building material waste, Chemical Engineering & Technology 23 (2000) 9, 809-814
Tomas, J: Particle Adhesion Fundamentals and Bulk Powder Consolidation,KONA – Powder and Particle 18 (2000), 157-169
Kollmann, Th., Reichmann, B. and J. Tomas: Time consolidation and caking be-haviour of soluble particulate solids, bulk solids handling 21 (2001) 4, 431-434
Reichmann, B. and J. Tomas: Expression behaviour of fine particle suspensions and the consolidated cake strength, Powder Technology 121 (2001) 2-3, 182-189
Schubert, S., Reichmann, B. und J. Tomas: Ermittlung der Schüttgutbelastung auf Bunkerabzugsförderer, Schüttgut 7 (2001) 1, 33-41
Kollmann, Th. and J. Tomas: Vibrational Flow of Cohesive Powders, in: Levy, A. and Kalman, H., Handbook of Conveying and Handling of Particulate Solids, 45-56, El-sevier, Amsterdam 2001
Tomas, J.: Particle Adhesion Fundamentals and Powder Flow Behaviour, in: Levy, A. and Kalman, H., Handbook of Conveying and Handling of Particulate Solids 761-769, Elsevier, Amsterdam 2001
Tomas, J., Computer aided hopper design method for cohesive nanopowders, Int. Conf. HUN-Pra-PARTEC, 168-178, Budapest 2001
Tomas, J. and Reichmann, B.: Compression, permeation and flow behaviour of wet nanoparticle cakes, in-situ tested with a press-shear-cell, Filtech Europa 2001, Vol 1, 47-55, Düsseldorf 2001
Tomas, J.: Flow Properties of Cohesive Powders, Int. Conf. Bulk Materials Storage, Handling and Transportation, Vol 1, 397-407, Newcastle (A) 2001
Kollmann, Th. and J. Tomas: The Influence of Vibrations on Flow Properties of Cohe-sive Powders, Int. Conf. Bulk Materials Storage, Handling and Transportation, Vol 1, 417-427, Newcastle (A) 2001
Kollmann, Th. and J. Tomas: Effect of Vibrations on Silo Hopper Design, Fine Pow-der Processing 2001, Pennsylvania State University, State College 2001
Tomas, J: Assessment of mechanical properties of cohesive particulate solids – part 1: particle contact constitutive model, Particulate Science & Technology 20 (2002) in print
Tomas, J: Assessment of mechanical properties of cohesive particulate solids – part 2: powder flow criteria, Particulate Science & Technology 20 (2002) in print