Cost-Effectively Crack Ammonia into Hydrogen Fuel

Abstract

Researchers at the University of Central Florida have developed two technologies for catalytically cracking ammonia into hydrogen as a fuel source. The technologies enable ammonia to be both a carrier of hydrogen as fuel and to provide cooling for compressor intercooling. Their use also helps to eliminate nitrogen oxides (NOx), air-polluting chemical compounds that form smog, ozone and acid rain. Compared to hydrogen storage, ammonia has advantages for volumetric energy density, safety, and the supply chain. Example applications include aircraft, land or water vehicles and power generation.

Technical Details:

• Ammonia-Hydrogen Cracking Device with Integrated Topology-Optimized Heat Exchanger (technology # 2023-016): Instead of burning ammonia directly, the UCF device catalytically cracks ammonia into hydrogen. With the technology, ammonia is a carrier of electricity-derived, green hydrogen for aviation, with near-zero emissions. The alternative aircraft fuel can compete with sustainable aviation fuels (SAFs) and hydrogen. With its non-coking properties, ammonia makes it a suitable heat sink for intercooling compressor air. Researchers adapted performance data of an existing aircraft engine for a modern narrow-body aircraft to the novel fuel concept. An intercooler was sized based on expected operating conditions on the ground and during flight.
• Combustion Liner with Integrated Cooling Channels for Ammonia Cracking (technology # 2024-021): Hydrogen-enabling can crack ammonia within the combustion liner. Gas turbines exhibit higher cycle efficiencies with increasing combustion temperatures, whether for power generation or aviation. Combustion liners, a crucial part of the combustion system, contain the flame and are exposed to some of the highest temperatures within gas turbine systems. They are actively cooled using compressor bleed air. Though viewed as an emerging fuel and hydrogen carrier to cut carbon emissions, ammonia is typically not combusted directly but rather cracked into hydrogen and nitrogen using a process that requires extensive energy and high temperatures. As a solution, the UCF technology involves cracking ammonia within the combustion liner, reducing the coolant requirement of the system. It also improves performance and durability while providing high heat levels at elevated temperatures for cracking. Internal or external channels coated with a catalyst act as cracking-promoting surfaces while cooling the combustion liner. The channels may or may not be additively manufactured and may or may not have turbulence-promoting features such as ribs, pins, or other engineered roughness.
  
  Partnering Opportunity: The research team is looking for partners to develop the technology further for commercialization.

Benefit

Market Application