Project Category: Chemical
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“Helping you find solutions for New Energy“
About our project
The objective of this project is to design a Small Modular Reactor that will provide clean energy for use in a synthetic fuel process in Alberta. Small Modular Reactors are nuclear reactors that generates 300 MW equivalent or less and can create clean power required to generate steam that can be used for oil and gas applications. The designed process will use the generated steam from the nuclear reactor for steam methane reforming to meet the growing demand for hydrogen in Alberta. This is one of the most common and least expensive processes for hydrogen production, due to its high efficiency of operation, about 70 to 85 percent, and low operational and production costs.
Reference: J. Conca, “NuScale’s Small Modular Nuclear Reactor Passes Biggest Hurdle Yet,” Forbes, 15-May-2018. [Online]. Available: https://www.forbes.com/sites/jamesconca/2018/05/15/nuscales-small-modular-nuclear-reactor-passes-biggest-hurdle-yet/?sh=49f2935e5bb5. [Accessed: 31-Mar-2021].
Meet our team members
Details about our design
HOW OUR DESIGN ADDRESSES PRACTICAL ISSUES
The Canadian Federal government wants to reduce greenhouse gases to 30 percent below 2005 levels by 2030 and plan to achieve net-zero emissions by 2050. There is motivation to move to nuclear energy as it is a cleaner energy source with zero-carbon emissions. The project tests the feasibility of integrating a nuclear reactor into a traditional oil and gas process, namely steam methane reforming, to help work towards this goal. Typically, producing the steam for this process requires a significant amount of energy to generate heat and releases toxic chemicals into the air. The small modular nuclear reactor addresses the issue of creating the steam required for the steam methane reforming process in a safe, reliable, and environmentally friendly way.
WHAT MAKES OUR DESIGN INNOVATIVE
Small Modular Nuclear Reactor
Our Small Modular Nuclear Reactor has been designed with a large focus on inherent safety. Specific design choices have been made to ensure the reactor’s ability to contain radioactive materials, control decay heat, and control the reactor reactivity:
- TRISO fuel elements consisting of multiple layered barriers to contain fission products within the coated particles under temperatures of 1620°C.
- Overall negative temperature reactivity under all operating and accident conditions.
- Helium as a neutron-transparent coolant.
See figures below for the automatic shutdown response of the reactor due to overall negative temperature reactivity. Please see our Github repo for our SMR code.
Synthetic Fuel Process
At NuEnergy Solutions, the main goal is to create cleaner energy while still utilizing existing infrastructure. The designed process is connecting a traditional oil and gas process with a renewable energy alternative. Through utilizing an SMR, there is a cleaner production of a hydrogen fuel product from steam methane reforming. In addition, the plan for the excess steam from the SMR is to utilize it to produce electricity. A key future recommendation of the project will include detailed design to integrate a co-generation process, where both electricity and hydrogen is produced.
WHAT MAKES OUR DESIGN SOLUTION EFFECTIVE
Small Modular Nuclear Reactor
In order to properly model the small modular reactor, a commercial counterpart was chosen to help validate and design the reactor. The top choices available were UK’s iPWR Westinghouse, Russia’s PWR KLT-40S, US SC–HTGR, Korea’s SMART, and China’s HTR-PM. For this project, China’s HTR-PM was selected as the best option to emulate. This is due to the use of helium as a reactor coolant, the graphite moderator, and the use of TRISO fuel elements. Using helium as a coolant eliminates the need to use water in the reactor, allowing the designed reactor to be placed in remote locations where water is not readily available. This helps to mitigate the potential of reactivity spikes due to water density and evaporation effects. The graphite moderator and the TRISO fuel particle selection also provide excellent negative reactivity feedback to the reactor. This enables automatic shut down in cases of coolant circulation malfunction or reactivity surges. The SMR design is versatile and inherently safe while producing steam needed for any process.
The SMR deploys the use of a complicated helium flow scheme to help minimize energy loss and maximize the power output:
Synthetic Fuel Process
Prior to selecting the steam methane reforming process to produce hydrogen, electrolysis and partial oxidation were also considered. Despite the electrolysis process being the most environmentally friendly and innovative, it was unable to meet the reliability criteria due to its novelty and lack of industry application. Compared to steam methane reforming and partial oxidation processes, steam methane reforming proved to be more favourable due to its economic feasibility, process efficiency, and extensive literature and history. Steam methane reforming was chosen as it yields the most hydrogen and there is already existing infrastructure in which the small modular reactor can be integrated.
In addition, this design solution is effective because it utilizes both a primary and secondary reformer. This will ensure the complete combustion of methane. Similarly, the designed process includes a high and low temperature gas shift reactor to ensure the complete reaction of carbon monoxide. This also leads to maximizing hydrogen production.
HOW WE VALIDATED OUR DESIGN SOLUTION
Small Modular Nuclear Reactor
The steady state power output of our modelled SMR is 388 MW. Using the 42% stated electrical efficiency of the HTR-PM, it is estimated that our SMR would produce 163 MWe. This meets the SMR classification requirement of being a nuclear reactor that generates 300 MWe equivalent or less.
Synthetic Fuel Process
In conjunction with the SMR, the steam methane reforming process is simulated in Symmetry. An effectiveness factor has been implemented to consider mass transfer resistance effects. In order to accurately simulate the model, a process calculator was used on Symmetry to implement the number of tubes in the plug flow reactors (PFR) for the primary and secondary reformer, as well as the high and low temperature gas shift reactors. This verified and gave a more accurate representation for the pressure drop across the PFR, which was hand calculated using the Ergun Equation. Additionally, the PFR models were all validated on MATLAB and compared to the Symmetry model output. As seen in the figures below, the PFR was successfully validated and matches with the Symmetry output.
FEASIBILITY OF OUR DESIGN SOLUTION
Our economics analysis shows the high profitability of nuclear energy implementation in Alberta’s energy industry. Utilizing a single SMR provides the steam requirement of a mid-scale steam methane reforming facility. While the startup costs remain high due to equipment costs, the payoff period is around 15 years. This analysis considers a low hydrogen sale value that is conservative and could have a comparatively higher economic benefit than pre-existing facilities.
Given the societal concerns over nuclear energy within Canada, several precautions and design considerations were developed to ensure safety, environmental and waste concerns.
An on-site spent fuel storage system (SFSS) will be used to hold the fuel for the plant lifetime. The fuel elements can retain radioactive material generated from the process and minimize release to the environment and operational staff.
Beyond the plant lifecycle, the fuel can then be transported to the future Canadian based deep geological repository. This is currently in development in locations such as Saskatchewan and Ontario.
Partners and mentors
We would like to specially thank the many people who helped us with this project. Our chemical engineering supervisor Dr. Michael Foley guided us through the process with patience and great advice. Thank you to Dr. Hector De la Hoz Siegler, the course coordinator of the chemical engineering capstone courses for guidance on more general capstone requirements.
Our photo gallery
Reference: IAEA, “Status report 96 – High Temperature Gas Cooled Reactor – Pebble-Bed Module (HTR-PM),” 2011.
