(Invited) Electrification of the Chemicals Industry Using Soec - Status of Activities at Haldor Topsoe
Authors: Blennow Peter , Küngas Rainer , Heiredal-Clausen Thomas , Nørby Tobias Holt , Rass-Hansen Jeppe , Hansen John Bøgild , Moses Poul Georg 
Published: May 2020

Haldor Topsoe considers electrolysis and solid oxide electrolysis cells (SOEC) in particular an enabling technology for the electrification of the chemical industry. We will present status updates on our various stepping stone projects: CO2 electrolysis for CO production and H2O electrolysis for biogas upgrading, as well as the demonstration project for the electrification of ammonia production.

Compared to other electrolysis technologies, SOEC allows for the conversion of CO2 into useful chemicals at very high efficiencies and at a faradaic yield of 100%. Haldor Topsoe is commercializing the CO2 electrolysis technology as eCOs™: a platform for on-site on-demand CO generation from CO2 feedstock for customers requiring a reliable and safe feed of carbon monoxide at a scale of up to thousands of Nm3 CO/h.

The use of SOEC for the production of H2 is also interesting, not merely due to the inherently high conversion efficiencies that can be achieved, but also due to system-level synergies found in integrating the endothermal electrolysis process with an exothermal chemical synthesis process. The pilot plant for upgrading CO2 in biogas into pipeline quality synthetic natural gas (SNG), located at Foulum, Denmark, provides an example of such integration. Long-term operation of the 16 Nm3/h H2 SOEC module integrated with a methanation unit will be presented.

Rapidly dropping renewable energy (RE) prices have created a unique opportunity space for introducing new technology based on electricity and RE, over the more conventional fossil-based processes. Electrolytic hydrogen production is a key technology for the transition towards a 100 % sustainable energy system, as it can both facilitate large-scale storage of renewable electricity (RE) and provide the necessary supply of CO2-free H2 for industrial use and for the production of sustainable fuel and chemicals. One of the most essential of the latter in our modern society is ammonia (NH3), which is used for fertilizer production and thus vital for feeding the world’s population.

Haldor Topsoe is a market leader in providing technological solutions and catalysts for the production of ammonia. Since 2000, Topsoe has commissioned >60 ammonia plants across the world with an accumulated capacity of almost 100 000 metric tonnes of NH3 per day. It is Haldor Topsoe’s ambition to become a technology provider for future fully electrified ammonia plants and a roadmap highlighting the key milestones towards SOEC + Haber-Bosch plants in 2030 will be presented. One scenario in that vision is to utilize the ability of SOEC stacks to operate in endothermal mode. A novel process is being developed where the nitrogen for the ammonia synthesis is provided by burning air between the SOEC stacks and utilizing steam generated in the Haber-Bosch loop as feedstock. This results in a very efficient plant (71 % LHV efficiency) and eliminates investment in an air separation unit.

Common for the applications mentioned above is that the SOEC stacks must have high robustness to handle dynamic operation, as well as long lifetimes, to lower the overall cost of stacks and systems. The technical features of Haldor Topsoe’s SOEC stack platform will be presented, along with lifetime test results of multi-stack configurations in different electrolysis operations.