Design of a hydrogen-on-demand (HOD) prototype using ammonia as a fuel source

Abstract

Hydrogen is increasingly considered as an alternative fuel to replace fossil fuels as the world is pressed by the accelerated global warming as a result of anthropogenic causes. However, adopting hydrogen is marred by issues in its distribution and storage and the high risks of leaks. Hydrogen carriers are considered to resolve those issues, and ammonia is greatly considered.

The aim of this project is to design, fabricate and test a hydrogen-on-demand (HOD) prototype using ammonia as a fuel source. The outcome of the project shows that using ammonia as a fuel source, the prototype had a long start-up and high operating temperature. Practical use of the prototype in producing hydrogen on demand would be limited to use cases such as industrial heating processes, long-haul trucks.

The project begins with a literature review on catalytic decomposition of ammonia followed by design considerations for the reaction vessel. The project then covers fabrication of a closed-end tube-shaped catalyst composing of Ni/YSZ and conducted a performance evaluation, with high ammonia conversion at 600 °C. The design and optimization of a metal vessel was also carried out, utilising Finite Element Analysis (FEA) with Autodesk Fusion 360, to ensure structural integrity. Finally, the author provides analysis to support the feasibility of the proposed HOD prototype.