Non-renewable and renewable exergy footprints of argon and oxygen in small-scale green ammonia plants ad by-products

Small-scale green ammonia plants have recently been projected as possible solutions to assist on decarbonizing both nitrogenfertilizers and food chain production, as well as producing a promising renewable energy vector. This study’s goal is to explorecoproduct opportunities in this type of industrial plant and their peculiarities. We evaluate our objective via saving non-renewable exergy costs co-products such as argon and oxygen. Our analysis applies circular thermoeconomics with the levelized exergy cost of electricity (LExCOE) concept to project these costs from distinct processes: a traditional cryogenic air unit, a pressure-swing adsorption unit, and a purge recovery from the ammonia plant. The exergy costs of water, green hydrogen, nitrogen, and renewable electricity (combinations between hydro, wind, and solar PV sources) account for both their extraction/production exergy efficiencies and the required infrastructure (material and energy intensities) to obtain them. This approach allows us to include current investments on renewables infrastructure from our energy sector transition. Finally, we shed a light on how these coproducts can be used by other economic sectors, such as an inert gas or a working fluid, and how this might improve the plant performance via industrial symbiosis opportunities