An European project that involves 6 PARTNERS in 5 countries

• Commissariat à l’Energie Atomique (CEA – F – Coordinator),
• University of Sheffield (USFD – UK),
• Università degli studi – Roma tre (DIMI – I),
• Deutsches Zentrum für Luft und Raumfahrt (DLR – D),
• Empresarios Agrupados (EA – SP),
• PROSIM (F)

Today, Hydrogen is mainly produced from fossil resources. In the long term, given the prospect of an increasing energy demand and a lack of fossil resources and limitations on the release of greenhouse gases, only water and biomass are viable, long term candidate raw materials for hydrogen production. The two processes that have the greatest likelihood of successful massive hydrogen production from water are electrolysis and thermo-chemical cycles. The thermo-chemical cycles are processes where water is decomposed into hydrogen and oxygen via chemical reactions using intermediate elements which are recycled. As the heat can be directly used, those cycles have the potential of a better efficiency than alkaline electrolysis.

The approach for accomplishing the project objective is multi-faceted. The approach includes: the search for the best basic flow-sheets for S_I and Hybrid Sulfur cycles (H2SO4 and HIx vapour phase modelling from experimentations) and their implementations in the ProSimPlus process simulation software, the study of the decomposition of H2SO4 in a solar furnace at high temperatures (1200C - direct heating and decomposition without catalyst - and 850C - indirect heating at a VHTR temperature) with the support of flow and thermo-mechanical dimensioning of the solar receiver, the experimental measurements of the partial pressures above a mixture of HI, H2O and I2 (use of FTIR, UV-Vis. and RAMAN spectroscopies), the modeling and experimental exploratory research into alternative, low energy separation techniques relevant to the S_I process (membranes – use of CARS spectroscopy), and the industrial scale-up of the S_I cycle to a a nuclear reactor and the Hybrid-Sulfur cycle to a solar and/or a nuclear source (couplings, safety assessments, components sizing and economics).

The project is in the second main period (01.04.2006 – 30.09.2007). A first S_I and WH cycles analysis round has been completed : S_I flow-sheet and industrial scale-up including a first economic evaluation and experimental results on H2 production step, experimental results obtained on H2SO4 solar decomposition, and solar coupled WH cycle modelling (flow-sheets, solar components sizing and costs). HYTHEC collaborations engaged with other European projects (RAPHAEL, HYSAFE, EXTREMAT).