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Design Optimization of an Ammonia-Based Distributed Sustainable Agricultural Energy System

Small-scale, distributed production of ammonia better enables the use of renewable energy for its synthesis than the current paradigm of large-scale, centralized production. Pursuant to this idea, a small-scale Haber-Bosch process has been installed at the West Central Research and Outreach Center (WCROC) in Morris, MN [1] and there is ongoing work on an absorbent-enhanced process at the University of Minnesota [2], [3]. Using renewables to make ammonia would greatly improve the sustainability of fertilizer production, which currently accounts for 1% of total global energy consumption [4]. The promise of renewable-powered, distributed ammonia production for sustainability is in fact not…

Paper

Lower Pressure Ammonia Synthesis

Ammonia is a very important chemical, mainly produced through the Haber-Bosch process. This process requires high temperature (>400 °C) and pressure (>150 bar) in order to ensure fast kinetics and high conversions, respectively.1 As a result, ammonia synthesis is known to be very complex and energy-intensive.2 To alleviate the complexity and energy requirements of ammonia synthesis, and to reduce the CO2 emissions, we are proposing an innovative reaction-absorption process to synthesize carbon-free ammonia in small plants.3 This green ammonia can be synthesized in wind-powered plants, with hydrogen from electrolysis of water and nitrogen from pressure swing adsorption of air.4 In…

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Small Scale Low-Pressure Ammonia Synthesis

Ammonia is one of the most important chemical commodities in the US and will be a key component in helping the world meet the rising demand for food and energy. Ammonia is needed in distributed locations for agriculture (as fertilizer for small grain and corn production), for indirect hydrogen storage1 (transported as a liquid at moderate pressure to hydrogen stations), or as a liquid fuel2 (for internal combustion engines or solid oxide fuel cells). Recently, there has been significant effort to develop scalable technologies for conversion of intermittent energies (e.g., solar, wind) into energy dense carbon-neutral liquid fuels, and ammonia…

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Potential Strategies for Distributed, Small-Scale Sustainable Ammonia Production

Potential Strategies for Distributed, Small-Scale Sustainable Ammonia Production Alon McCormick*, Ed Cussler, Prodromos Daoutidis, Paul Dauenhauer, Lanny Schmidt, Chemical Engineering and Materials Science; Roger Ruan, Doug Tiffany, Bioproducts and Biosystems Engineering; Steve Kelley, Humphrey School of Public Affairs; Mike Reese, West Central Research and Outreach Center, University of Minnesota

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Life-cycle greenhouse gas and energy balance of community-scale wind powered ammonia production

As well as being an innovative energy source, ammonia is a crucial component of most nitrogen fertilizers. Since the production of ammonia is very energy intensive and currently completely based on fossil energy, there is a considerable interest in developing renewably produced ammonia for use in agriculture and other sectors. This work presents a life cycle assessment (cradle-to-gate) of greenhouse gas (GHG) emissions and primary energy use for ammonia produced at community-scale using renewable wind generated electricity. Two different regions were studied: Minnesota (US) and Sweden. The results show that ammonia produced with wind-generated electricity has significantly lower fossil energy…

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Ammonia Production Using Wind Energy: An Early Calculation of Life Cycle Carbon Emissions and Fossil Energy Consumption

Industry professionals and others have begun to consider the use of ammonia as a substitute for fossil energy in the fuel, fertilizer, and chemical sectors. Several factors are driving this concept; including, energy security concerns, the potential for economic development, and reducing the environmental consequences of fossil energy use. In terms of environmental concerns, it is important to determine the potential impacts of producing ammonia before a major switch to ammonia can be considered. This study examined fossil energy use and carbon emissions in the production of ammonia, using life cycle assessment (LCA) methods to analyze production at a novel…