Application of water electrolysis for green ammonia production: a plant simulation study

Abstract

Renewable energy has received a significant global attention. Green hydrogen is undoubtedly a viable energy source due to its efficiency and environmental friendliness. Thus, this study was proposed to provide insights about the design and feasibility of switching from natural gas to green hyrogen for the production of ammonia. The aim of this study is to design a green ammonia plant with a capacity of 140000 tons per year using green hydrogen and raw nitrogen. The inclusive study involved process simulation using ASPEN HYSYS v11.0, Equipment design, equipment spacing, plant layout, and finally evaluation of profitability. The plant design was made for all the units including heat exchangers, separators, reactors, etc., and is completed based on the data calculated by material and energy balance. Results revealed that, approximately, 189920 tons/year of water and a 2 MW electrolyzer are required to achieve the desired production. The overall process is highly exothermic effluent temperature from the electrolyzer and ammonia reactor increased by 160% and 68%, respectively. The economic investigation showed that the fixed capital investment required is approximate 22.4 million USD. The production cost of green ammonia was $1350/ton which is comparable to the global price of $1400/ton.