2006 Spring Meeting & 2nd Global Congress on Process Safety
(10d) Filtration + Magnetic Field = Nanoseparation
Authors
Fuchs, B. - Presenter, DuPont
Stolarski, M. - Presenter, University of Karlsruhe
Keller, K. - Presenter, DuPont Engineering Research and Technology
Nirschl, H. - Presenter, Institute for Mechanical Process Engineering and Mechanics
Stahl, W. - Presenter, University of Karlsruhe
Nanoseparation is known to be one of the challenging aspects of solid-liquid separation. The development strategy to satisfy the needs for nanoseparation is mainly to increase driving forces like mechanical pressure, gas pressure or centrifugal forces. A very good example is the tubular bowl centrifuge, which works at g-factors around 100000. But the limiting factor of these centrifuges is the throughput. Even though an increase of gas pressure during filtration might also be a good approach, crack formation due to the small particles and therefore dominating particle interactions might undo any benefits since the gas-pressure will collapse. This work shows how a combination of magnetic field and filtration improves the separation especially for iron oxide pigments. It also shows the influence of the magnetic field on the cake structure and the internal strength of the filter cake. First results show that the magnetic field can support or prevent crack formation depending on its direction and strength.