Alejandro J. Santis-Alvarez

A fast hybrid start-up process for thermally self-sustained catalyticn-butane reforming in micro-SOFC power plants

This work aims at the investigation and optimization of a hybrid start-up process for a self-sustained reactor for n-butane to syngas conversion in intermediate temperature, micro-solid oxide fuel cell (micro-SOFC) power plants. The catalytic reaction is carried out in the presence of Rh-doped Ce0.5Zr0.5O2nanoparticles in a disk-shaped reactor. For the start-up, a resistance heater is embedded inside the catalytic bed and is activated until the exothermic oxidative reaction is initiated. The self-sustained temperature and reforming performance are demonstrated to be highly dependent on the fuel to oxygen (C/O) ratio and the catalytic activity at different space times. It is shown that a C/O ratio of 0.8 is a very good choice in terms of achieved steady-state temperature, syngas selectivity and start-up time. At a reactor inlet temperature of 809 °C for a C/O ratio of 0.8 and a space time as low as 8 ms, a syngas selectivity of 69.6% and a temperature of 529 °C at the simulated micro-SOFC membrane are demonstrated. After only 15 s from ignition, a temperature of 600 °C at the reactor inlet is reached. The hybrid start-up process is optimized with respect to a specific setup as an example, but is of general nature and utility to similar systems.

Self-Sustained Partial Oxidation of N-Butane Triggered by a Hybrid Start-Up Process for Micro-SOFC Devices

Micro-solid oxide fuel cell (SOFC) power plants are emerging as a promising alternative for power generation for portable applications due to their low emission of pollutants, high power density and fuel flexibility. Some of the challenges for developing such micro-SOFC power plants are geometrical compactness, fast start-up and self-sustainability at operating conditions. In this work, we present a hybrid start-up process for a micro-SOFC power plant using catalytic oxidation of n-butane over Rh-doped Ce0.5 Zr0.5 O2 nanoparticles in a small-scale reactor to provide the necessary intermediate operating temperature (500–550 °C) and syngas (CO + H2 ) as fuel for a micro-SOFC membrane. A short heating wire is used to generate the heat required to trigger the oxidative reaction. The hybrid start-up is investigated for partial oxidation (POX) and total oxidation (TOX) ratios at one specified flow rate. Additionally, the variation of electrical heating time and its influence on the hybrid start-up is evaluated.Copyright