Techno-Economic Evaluation of Green NH₃ Production by Integrating Current-Assisted Reaction and Ionic Liquid Absorption

In this work, an ammonia (NH3) synthesis loop under mild conditions (595 K and 20 bar) was constructed, including a current-assisted reaction unit and a separation unit based on ionic liquid absorption. ASPEN Plus was used to simulate the NH3 synthesis loop with a capacity of 20,000 tons per year, where the reactor was a customized model. Based on the simulation results, the techno-economic evaluation of a miniaturized green NH3 production plant was carried out, with hydrogen from water electrolysis and nitrogen from pressure swing adsorption. The levelized cost of ammonia (LCOA) in the reaction-absorption (RXN-ABS) process was obtained to be 838.81 $ tNH3−1. The LCOA in the RXN-ABS process is 18.56% and 10.09% lower than the reported reaction-condensation (RXN-CON) and reaction-adsorption (RXN-ADS) processes, respectively. If the revenue from oxygen sales is taken into account, the RXN-ABS process can achieve an after-tax return of 34.72%. As the price of renewable electricity decreases to 0.024 $ kWh−1 and electricity consumption of water electrolysis decreases to 5.58 kWh kgNH3−1, the LCOA in the RXN-ABS process can be lower than the selling price of NH3. The new NH3 synthesis loop has better economy and safety, which promotes the popularization of the distributed NH3 production technology.