(202a) Utilization of Nuscale Voygr NPP Integrated Energy System (IES) for the Production of Decarbonized Ammonia

Ammonia is a highly versatile chemical widely used for industrial purposes and prevalent in our everyday lives. The industrial applications of ammonia are vast and diverse. One of its primary uses is as a key ingredient in fertilizers. Ammonia is also used in the production of numerous chemicals, including plastics, textiles, and pharmaceuticals. Its ability to bond with water makes it an ideal refrigerant, used in large-scale cooling systems such as those found in food storage and processing facilities. Its unique properties and diverse range of applications make ammonia a critical component of modern industry.

Ammonia is almost exclusively produced using the Haber-Bosch process, which reacts nitrogen (N₂) and hydrogen (H₂) with a heterogeneous metal catalyst to produce ammonia (NH₃). Currently, the predominant method of producing the necessary hydrogen is the steam-methane reforming (SMR) process in which natural gas containing methane (CH₄) is reacted with steam. Unfortunately, this process results in significant CO₂ emissions into the atmosphere.

A decarbonized approach to generate NH₃ would be to use an Integrated Energy System (IES) that includes a NuScale VOYGR nuclear power plant (NPP) for electric power and steam production. The IES would be coupled to a High-Temperature-Steam-Electrolysis (HTSE) system containing Solid Oxide Electrolysis Cell (SOEC) stacks for hydrogen and oxygen production. The following is a listing of the functions of the subsystems and the intermediate materials for the entire production process as well as the expected NPP inputs:

• Reverse Osmosis (RO) Water Treatment – Clean water into steam generator to produce steam (power)
• Steam Generator – High quality steam into HTSE for hydrogen production (steam)
• HTSE System – Hydrogen and oxygen production (power)
• Nitrogen Generation – Air separation (power)
• Ammonia Production – Reacting hydrogen and nitrogen to produce ammonia (power)

RO Water Treatment – NuScale internal research has demonstrated that RO technology when coupled with NuScale VOYGR NPP generate the smallest carbon footprints (g-CO₂ per m³ of clean water) when compare to other energy sources including renewable and hydropower.

Steam Generation – NuScale has studied the control strategies needed to divert a portion of the steam produced (in its secondary process, isolated from radiation) away from the steam turbine for power production and towards providing thermal energy to an adjacent process. In this application, the superheated steam is used to generate saturated steam to feed to the HTSE system.

Hydrogen Production - NuScale has teamed up with DOE National Lab and technology companies to investigate in using NuScale VOYGR NPP for the production of Hydrogen and Oxygen via the HTSE-SOEC technology (Ref 1 and 2). Other electrolyzer technologies can certainly be considered (such as Polymer Electrolyte Membrane, PEM, and Alkaline Electrolysis, AEL), but the HTSE system is particularly well suited in this application as the NPP provides both thermal and electrical energy, increasing its total system efficiency to 90% higher heating value (HHV). As indicated above, the thermal energy directly generates the steam feed to the HTSE and the electrical energy supplies power to the SOEC, feed gas compression to the Haber-Bosch process, and all balance of plant requirements.

Nitrogen Production - There are three methods for the generation of nitrogen from air components: a) Pressure-Swing-Absorption (PSA), b) membrane, and c) cryogenic systems. All the prescribed processes to generate nitrogen require significant amounts of energy (primarily electrical) to compress, heat/cool, and purify the N₂.

Ammonia Production – The Haber-Bosch process involves compressing the feed gases N2 and H2 to ~300 bar and ~450C. The feed gases enter a reactor containing a metal heterogeneous catalyst. The reaction is a mildly exothermic equilibrium reaction. The outlet gases are cooled to condense ammonia and the unreacted N2 and H2 recycled back to the reactor. Electrical power is used to compress the inlet gases and provide heating and cooling as needed.

NuScale Power is the industry-leading provider of proprietary and innovative advanced small modular reactor nuclear technology. It delivers scalable, and reliable carbon-free energy. NuScale VOYGR Small Modular Reactor Power Plant system’s modularity and flexibility is uniquely qualified to support desalination operations, especially for large-scale production systems. NuScale VOYGR™ SMR plants are powered by the NuScale Power Module™—each a small, safe, pressurized water reactor that can generate 77 megawatts of electricity (MWe) or 250 megawatts thermal (gross), and can be scaled to meet operational needs through an array of flexible configurations up to 924 MWe (12 modules) of output.

The NuScale SMR is the only small modular reactor to have its design certified by the U.S. Nuclear Regulatory Commission and published in the Federal Register on February 3, 2023 (Ref 3). In addition, the standard Emergency Planning Zone (EPZ) for existing NPPs is a 10-mile radius. However, the NRC approved the NuScale (EPZ) sizing methodology, limiting the EPZ to the site boundary of the power plant for a wide range of potential plant sites where a NuScale VOYGR SMR power plant could be located. This means that users of the plant's output can be located in close proximity. Therefore, NuScale is well positioned to serve diverse customers across the world by supplying nuclear energy for electrical generation, district heating, desalination, commercial-scale hydrogen production, and other process heat applications.

The attached image shows Figure 1: the setup and the coupling of the NuScale VOYGR NPP to all the subsystems and components for the production of decarbonized ammonia and Figure 2: a detailed NuScale VOYGR plant site layout.

References

• Idaho National Lab Report, INL/LTD 14-31039, February 2014 (Limited Distribution)
• Idaho National Lab Report, INL/EXT-19-55395 Rev.1, September 2019
• https://www.federalregister.gov/documents/2023/01/19/2023-00729/nuscale-small-modular-reactor-design-certification