Simulative and Experimental Investigation of Heat Transfer in Chemical Fixed-Bed Reactors

In general, the execution of chemical reactions requires the supply or removal of heat. In conventional heating concepts for catalytic reactions, heat transfer usually takes place through the outer surface of the reactor tubes. The resulting temperature gradient between the reactor wall and the center of the reactor limits the design of tubular reactors. An accurate simulation-based description of the resulting radial temperature gradient within the reactor is based on a thorough understanding of the underlying heat transfer phenomena. Established modeling approaches for fixed-bed reactors differ fundamentally in terms of model depth, whereby the number of experimentally determined model parameters increases with increasing level of detail.

My research focuses on the modeling of heat transfer in fixed-bed reactors as well as the experimental determination of required model parameters. The experimental investigation of heat transfer phenomena is carried out by measuring temperature profiles within the fixed-bed reactor using fiber-optic measurement technology. For this purpose, the sensor fiber is integrated into the catalyst bed, where a large number of temperature measurement points enable the determination of a spatially highly resolved temperature profile.

Fiber-optic measurement technology also enables the characterization of an electric reactor heating system for catalyzed, endothermic reactions. The heat distribution of a modularly integrable ohmic resistance heating system for tubular reactors is investigated. In addition, simulation studies are conducted to design this electrically heated reactor and to compare it with conventionally heated tubular reactors.