Wärmeintegrierte Reaktorkonzepte für katalytische Hochtemperatur-Synthesen am Beispiel der dezentralen Dampfreformierung von Methan [article]

Achim Gritsch, Universität Stuttgart, Universität Stuttgart
2008
Small scale mobile and decentralized polymer-electrolyte-membrane-fuel-cell units for power generation from hydrogen are currently within the focus of the automobile and power industry. The worldwide progress of the fuel cell technology results in an increasing demand for pure hydrogen from compact and energy efficient syngas facilities. Conventional large scale reforming technologies for hydro¬gen production cannot meet these requirements since the reforming reaction runs under severe heat
more » ... der severe heat transfer limitations, requiring large reactor volumes and resulting in insufficient energy efficiency. A much more intensive coupling of endothermic steam reforming and catalytic combustion in a heat-exchanger reactor with narrow parallel channels and efficient heat recovery from the hot products to heat up the cold feeds in counter-current heat exchangers is a promising approach to overcome the above limitations. Within the scope of this work the behaviour and performance of the heat integrated reformer concepts under counter- or co-current operation mode were systematically investigated and evaluated through simulation studies. The energy efficient and controlled heat supply of the reforming reaction requires a co-current reformer with one additional fuel injection side-port and two separate counter-current heat exchangers for heat recovery. The temperature level within the reactor can be efficiently adjusted over a wide load range through the distribution of the combustion fuel over the reactor inlet and the side-port. The development of a novel prototype reformer was achieved by the combination of simulation studies with specific experiments. The results of the experimental investigations including kinetic studies on steam reforming of methane, on the control of heat generation by combustion of methane and hydrogen as well as the coupling of both reactions under co-current operation mode pointed out the required process conditions and were used for a reliable model based design and optimization of the prototype reformer. T [...]
doi:10.18419/opus-1771 fatcat:7mnozshjjzhdrnpqvq47hmzg7q