Compact Multifuel-Energy to Hydrogen converter
Key Objectives of the project
CoMETHy aims at the intensification of hydrogen production processes, developing an innovative compact and modular steam reformer to convert reformable fuels (natural gas, biogas, bioethanol, etc.) to pure hydrogen, adaptable to several heat sources (solar, biomass, fossil, etc.) depending on the locally available energy mix. Therefore, the developed system will be featured by two degrees of flexibility, either in terms of the feedstock that is converted to hydrogen, and in terms of the primary energy source. Indeed, CoMETHy aims at supporting the transition from a fossil-based to a renewable-based energy economy, providing a flexible technology for different energy scenarios.
The objective is to provide a reformer for decentralized hydrogen production (i.e. close to the end-user), thus surmounting the actual lack (and costs) of a reliable hydrogen distribution infrastructure.
CoMETHy proposes a new “low-temperature” steam reforming technology, where a molten salt (molten nitrates mixture) at maximum temperatures of 550°C is used as the heat transfer fluid. This concept allows recovery and supply of the process heat to the reformer from different heat sources like solar. The produced hydrogen is separated and purified by means of selective membranes.
First challenge is the development of advanced low-temperature steam reforming catalysts and cost-effective selective membranes in the reference operational range (400-550°C, 1-10 bar). Next technical challenge is targeted on the coupling of the membrane with the catalyst in a membrane reactor. Finally, the project involves the integration of the developed membrane reformer in a molten salts loop for proof-of-concept at the 2 Nm3/h hydrogen production scale, and the performance assessment of the whole system.
The first year of the project is mainly focused on the development of the two key components, catalyst and membrane, to provide basic recommendation about the catalyst system and the membrane to be applied. This represents input to the reformer design and validation as key activity during the 2nd project year. Finally, after construction of the 2 Nm3/h pilot unit, the 3rd project year is mostly dedicated to the proof-of-concept and to optimization and evaluation of the whole. In the perspective of a multi-fuel application, the identification of specific catalysts for bioethanol steam reforming is required too.
Expected socio and economic impact
CoMETHy proposes a new steam reforming concept for decentralized hydrogen production with potential benefits in terms of production costs, operational flexibility and environment impact.
Reduction of steam reforming temperatures to less than 550°C allows use of costless construction materials (no special steel alloy typical of conventional steam reforming are required), and elimination of the water-gas-shift reactor(s), whereas the integration with membranes avoids dedicated hydrogen separation and purification units.
Moreover, this system can operate with different sources (depending on local availability) and the decentralized production avoids distribution costs. The coupling with renewable heat sources (like solar heat from CSP plants) makes production cost less sensible to the fossil fuel price and allows a substantial reduction of CO2 emissions (and corresponding fossil fuel consumption) in methane steam reforming, being the order of 40-50% with respect to the conventional process, whereas the use of biofulels (biogas, bioethanol, etc.) allows totally green hydrogen production.