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Conclusion
Although several commercial simulation tools for modeling solids applications are
available on the market, it is not possible to describe the highly complex Mueller-
Rochow fluidized-bed process sufficiently. So an own, tailored simulation model was
created, comprising all the relevant influence parameters. During the modeling work
extensive experiments were carried out in order to identify and quantify these influence
parameters. For that purpose, a pilot plant was built in cooperation with Hamburg
University of Technology to investigate the fluid dynamics of the fluidized-bed process,
including the influence of different internal configurations on the gas bubble behavior
and on particle entrainment. Furthermore, a second pilot plant was used to investigate
the MCS reaction. Based on the know-how and on the basic data provided by the pilot
plants, an own integrated and holistic simulation model of the Mueller- Rochow process
was gradually developed and validated.
This comprehensive fluidized-bed simulation tool now can be used to optimize yield,
selectivity and silicon utilization efficiency of the Mueller-Rochow reactor. The
optimization work can concentrate on different aspects of the process such as on
operational parameters, such as gas flow rates, temperatures or pressures, but also on
the design of the reactor and internals, as well as on different grain sizes, with the aim
of achieving operational excellence.
References
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E.G. Rochow, US Pat. 2 380 995, General Electric, 1941.
2.
R. Mueller, Deutsches Patent DD 5 348, VEB Siliconchemie, 1942.
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Silicones
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168