CHE.01 – Blue Ammonia

• Megan Carlson
• Andrew Russ

Blue ammonia is synthesized using nitrogen and “blue” hydrogen sourced from natural gas feedstocks. The environmentally unfriendly carbon dioxide byproduct is captured and stored as a means to reduce the adverse environmental impact of the production process. Due to the favorable feed methane and product ammonia prices, the plant is located in an industrial district in Argentina. By feeding separated carbon species into underground storage areas, the carbon footprint of the plant is reduced to exclusively electricity sourced from non-renewable means and fired heater exhaust fumes. The process itself uses one steam methane reformer with two competing reactions. The products are mixed with steam in two water gas shift reactors operating in series prior to separation. The separation uses a pressure swing adsorber to separate nonreacting components from the hydrogen. The pure hydrogen stream is mixed with nitrogen sourced from an air separation unit. These components are mixed with recycled nitrogen and hydrogen prior to being reacted in an ammonia synthesis reactor. The high purity ammonia product is then separated from the residual nitrogen and hydrogen by cooling and expanding the stream prior to ultimately being stored and sold. This process demonstrates how an industrial scale ammonia plant can maintain large output quantities while focusing on environmental impact.