Design and Analysis of Ammonia Synthesis and Utilization Networks

Ammonia is a fundamental commodity that boosts a well-established supply chain optimized for over a century. Produced primarily by the Haber-Bosch process, ammonia production has become more efficient over time through many technological advancements. However, it entails a significant carbon footprint due to its use of hydrogen obtained from fossil fuels. The need to address these sustainability challenges raised by the demand for fossil fuel and subsequent greenhouse gas emissions paved the way for several renewable production routes. As more sustainable means of production were developed, the range of ammonia’s applicability also expanded. While ammonia continues to be a vital fertilizer and raw material for various commodity chemicals globally, its potential as a critical energy carrier presently takes center stage. Primarily seen as a hydrogen carrier, ammonia’s decomposition into hydrogen and nitrogen was deemed necessary and led to the recent advancements for its direct application as a fuel. Thus, ammonia has several sustainable synthesis and utilization routes that must be carefully analyzed to explore synergies that further promote circularity. This work enables the design of profitable ammonia synthesis and utilization networks from a set of extensive processes with emission constraints through a robust multi-resource integration model. The optimization determined carbon-negative solutions under specified distribution scenarios that integrated green ammonia synthesis with carbon capture and utilization, renewable energy, and negative emissions technologies, achieving net removals of 652,000 and 350,936 t of carbon dioxide annually, while respectively generating profits of 573 and 263 M$/y.