Comparative life cycle assessment of ammonia production pathways

Abstract

This Master's Thesis uses life cycle assessments to compare and evaluate four production pathways of ammonia production and evaluate the extent to which they will reduce Global Warming Potential. The manufacture of ammonia is projected to undergo significant transition with recent legislative changes, and these changes will alter the methods used to produce ammonia. The production pathways are referred to by a color code that represents the source of hydrogen used in the production process. Green - hydrogen from renewables, grey - hydrogen from fossil fuels, blue - fossil fuels but with carbon capture, and pink - nuclear energy. A hypothetical ammonia production facility in the predesign phase is used as a test case. The four production pathways are assessed for their potential to reduce global warming potential. Additional impact areas will also be examined to estimate impacts in other ecological categories. The results show that there are trade offs with increased environmental burden in categories other than green house gas emission, but green ammonia production has the potential to reduce the global warming potential of ammonia production.