The future of thorium nuclear energy - A discussion

The Future of Thorium Nuclear Energy A Discussion with Walter Horsting (WH – business development, USA) Eric Jelinski (EJ – nuclear expert, Canada) Kelvin Kemm (KK 2 – nuclear physicist, South Africa) Jim Kennedy (JK 2 – rare earth elements and thorium mining expert, USA) Kenneth Kok (KK – nuclear expert, USA) John Kutsch (JK – Thorium Energy Alliance, USA) John Shanahan (JS – civil engineer, USA) February 2020 JK Even with today’s license paradigm you could obtain a license in 36 months - call it 40 not a rocket, but a bearable amount of time that you can spend doing site specific work and prefabrication and training etc.

There is no reason to take more than 2 years to build a reactor - that is what the Koreans can do and that is how long a 1,000 MW combined cycle system. And time is the reason it costs so much to build .

So, the idea that a small PWR , a design that is 60 years old, would take that long is nutty. But it shows these companies are just in it to juice grants. . . . who know's what they hope to achieve.

In the end we can transition to Thorium for many things and we can do it very quickly, I believe the work that Jim Kennedy and I are doing will vastly expedite the a paradigm shift in materials and energy resources.

We appreciate any support you can give us - it appears we may be close a policy change that can make things speed along faster.

1

EJ Some analysis work and some testing has been done on the Pressure Tube Heavy Water Reactor (formerly known as Candu™ ) by Canadian Nuclear Laboratories (ex AECL), and also by some others. The government of India comes to mind.

Here is a report in the public domain, https://pubs.cnl.ca/doi/10.12943/CNR.2016.00043.

Since the PTHWR reactor is already licensed in a number of countries, the license change will be mostly to change the fuel design and fuelling sequence. Thorium needs a starter fuel, obviously available via the natural U and augmented by some Pu bread from U238 during fuel residence time. One could convert this reactor to 100% Th where the fissile material is U233 converted from the Th232.

A simplified diagram for conversion is here,

A further enhancement is to increase the neutron economy of the PTHWR by separating the Zr isotopes to increase the desired Zr90 content to 95% or higher, while removing the heavier and more neutron absorbing isotopes (Zr91, Zr92, Zr94, Zr96).

The attached email was a proposal for a university graduate student project I had submitted a couple of years ago. So far, I have not found any traction on this. Perhaps by posting the idea here, it may gain traction to move forward. I have done a literature survey on this topic and if anybody (student or professor) would like that background info they may please send me an email to request that.

The PTHWR could be built as an SMR recognizing there needs to be enough mass of fuel for a critical mass as the reactor volume decreases. However, we have on record built and operated a Nuclear Power Demonstration 25MW(e) unit, and then scaled up to Douglas Point 300 MW(e), then further scaled up to the nominal 900 MW(e) presently in service.

2

EJ Zirconium Upgrade Project Proposal The basis for the Pressure Tube Heavy Water Reactor, of which the Candu™ is a specific design uses, and is able to use, natural uranium, in conjunction with a moderator of heavy water, (D2O). There are a number of reasons why this is feasible, and the primary reason is due to neutron economy. In plain speak, the parasitic absorption of neutrons is kept as low as possible by way of the D2O moderator and reactor internal components, calandria tubes, pressure tubes, and fuel bundles/fuel assemblies manufactured from Zirconium alloys that have low neutron absorption as the primary nuclear property, as well as good chemical and mechanical properties to achieve their purpose. This has been the basis for the design of Pressure Tube Heavy Water Reactors in Canada and other countries for the past 60 years.

However, we can do better in several key areas, improving overall safety, improving burn-up (fuel utilization), assisting transition to Thorium, actinide burning, and reduce both the mass and the timeline for dealing with long term spent fuel management via the Deep Geological Repository.

Proposal A detailed examination of reactor physics, and thermal hydraulics, as well as examining the nuclear properties of Zirconium, ‘the front end’ opportunities lie in reducing parasitic absorption of neutrons in the Zirconium by removing the naturally occurring detrimental isotopes of zirconium.

Upon examining the nuclear properties of Zirconium, there are 5 isotopes that are stable and naturally occurring. The heavier isotopes have high neutron absorption cross sections and therefore removal of these results in improved neutron economy. I recommend to investigate the feasibility of a plant design for the enrichment of zirconium to increase the desired Zr-90 content to 95% or higher, while removing the heavier and more neutron absorbing isotopes (Zr-91, Zr-92, Zr-94, Zr-96). There is an added side benefit by reducing the content of Zr-92, because each Zr-92 isotope absorbs a neutron, becoming Zr-93, that has a very long half-life (1.5 million years), presenting a long-term radiological hazard for spent fuel.

Thus, if we can reduce the amount of Zr-92 in the Zr used for fuel cladding, pressure tubes, and calandria tubes, we can also reduce the radioactivity of the structural components, reducing radiation dose to workers during refurbishment/life extension, inspection and maintenance and making long-term waste management easier. Having a design for improving the relative amount of the desired Zr-90 isotope would be of immediate benefit to all reactors by way of all fuel assemblies manufactured from improved Zr component, of some 400 light water reactors. Eg. Not only in the long term disposal aspect, but perhaps in reducing the level of enrichment required for the U-235, or somewhat longer run times between refuelling outages. There is also a 3

potential benefit for some future advanced molten salt and/or small modular reactors using ZrF4 as the coolant.

The above recommendation has basis in papers authored by staff at Canadian Nuclear Laboratories, eg. http://pubs.cnl.ca/doi/full/10.12943/CNR.2016.00043.

This project proposal is groundbreaking, leading edge, and game changing with far reaching national and international benefits.

Some searching of literature for ideas is in attached files as a project starting point for anybody wanting some guidance that includes some patent searches and ideas generated to work with. In summary, the main processes for Zr separation appear to be either laser, or centrifuge (see Aerodynamic Separation Process). The laser process may also be an option for D2O, however the starting point should be to review existing open source literature as listed in the links in the attached word document. Ideally also, there should be opportunity to do laboratory testing of the process.

Possible path forward 1. Literature review to investigate existing technologies or techniques to be developed for chemical separation of Zr-Isotopes on an industrial scale.

2. Create a decision analysis matrix with candidate chemical processes to make recommendations based on feasibility and economics.

3. Development of a prototype plant for Zirconium enrichment to 95wt% Zr90.

Possible Zr-Isotope Separation Technologies a) b) c) d) e)

Extension of standard Zr/Hafnium separation process (Thiocyanate) Chromatographic Separation Balanced Ion Electromigration Tuned Laser Beam Separation Technique Selective Two-Colour Resonant Ionization of Zr-91

A reference from long ago. You may need to go through official channels at OPG to obtain a copy of it.

You could try U of Toronto library as sometimes OH research gave copies to the U of T engineering library by way of U of T professors who may have been involved at that time.

4

JK Candus are pretty darn good reactors, and Canada should be proud of the engineering achievement.

They've proven themselves to be very reliable which is amazing because of their complexity.

Editor’s NOTE: CANDU nuclear plants are simpler in may ways that LWR technology.

The Chinese have proven that thorium is a reasonable fuel to use inside a Candu, the fuel shuffling and the plutonium seem to be the trick to getting solid fuel thorium to work.

I personally think simplicity and elegance of a molten salt reactor is worth doing the R&D work and pulling the materials and chemistry and redox across the finish line. The fabrication of a large Fleet of molten salt reactors would be easily done in a small size and you could transport in component pieces via Road and rail very easily.

The key here, the start of this discussion, nuclear power’s real problem is in fact the construction time, build cost of capital, and tied in with that is the licensing Paradigm that we must work within for now.

If anyone wants to go ahead and build any licensed design while we are waiting for the much better more elegant designs coming down the road, I am in full support of that, even better would be to introduce things like the light Bridge cruciform fuel bundles that would let us optimize fuel burn up and get more power from the same reactor Fleet and also utilize thorium pretty well.

In short, there are so many things we could do 2 greatly increase the output and run liability of the nuclear Fleet of the world, while also Expediting the rollout of a new generation of reactors.

A final thought is that the distracting idea that we have to make these reactors play nice with Renewables. I think this is exactly the way to distract and increase cost and complexity. I always tell people: "Renewables need nuclear, nuclear does not need Renewables."

5

Koeberg nuclear power station, South Africa Well designed and managed nuclear power around the world is a tremendous benefit for humanity and wildlife, here roaming free near the power plant.

WH SUSTAINATOPIA 2017. THE CASE FOR A GOOD REACTOR Coal and fossil fuels have lifted mankind out of hard labor and poverty but with an increasingly high environmental cost. The truth about nuclear is quite simple. Only nuclear power can lift all the World’s poor out of energy poverty without keeping cities like Delhi and Beijing caked in deadly particulate matter. The Liquid-Fuel Reactor Molten Salt Reactor (MSR). *Aircraft assembly line production, *Can’t melt down, *Can’t blow up, *Walk-away safe, *One-third the cost to build due to its inherent safety of low-pressure design, * Can make fuel from Thorium.

See full article, click here.

KK This has been a very interesting discussion with some interesting options. I would like to relate a personal experience regarding the development of a molten salt reactor system.

Five years ago, I was approached by a group that was interested in the possibility of building a molten salt reactor design test facility that could be eventually operated as an actual molten sat power generating facility. The test facility was to be built full scale and operated with electric heaters to test all the non-nuclear systems. There are two approved reactor sites adjacent to the Columbia generating station where much of the infrastructure such as cooling water supply are already available. Hand ford was selected because of access to barge transportation for large components allowing off site 6

fabrication. The only nuclear permit required could be issued by the State of Washington for the depleted uranium that was to be included in the experiment as a surrogate for the actual enriched uranium fuel. Locally there was good support for the idea. The test facility would have been privately financed and open to both the DOE and the NRC so that they could observe the experimental process. The plan was to operate the facility for 12-24 months prior to applying for a reactor operating license. Effectively the system was a scaleup of the MSRE that had successfully operated of ORNL over 50 years before. After discussions locally a meeting was scheduled with the NRC to discuss the future licensing process.

The meeting did not go well. The NRC personnel in attendance had no concept of what a fluid fueled reactor was and how it operated. Questions were asked about the absence of a pressure vessel and control rod drive systems. We were told that a facility such as the one proposed would not yield any acceptable data to support licensing unless it was totally built and operated under a full NRC approved NQA-1 quality system. In other words, we had to get all the structural materials, instrumentation, construction processes, data collection, etc. approved by the NRC before the data generated could be used for licensing. Even any data from the MSRE was considered unacceptable. The estimated time to proceed in this manner was 20+ years.

The development team has packed up and moved offshore. The problem in the US is the licensing process. A system like the Canadian Candu Works fine but getting one licensed under the USNRC would be nearly impossible in a relative short time frame. By itself a nuclear reactor is a fairly simple device. I operated and ran a 2 MW research reactor. I could see the reactor core under 20 feet of water. The core was 18” by 18” by 24” and contained 33 fuel elements with three element spaces open for experiments. If ran 24 hours a day for 18 out of every 21 days for 19 years before is was shut down and decommissioned. The original safety analysis supporting the original license was 12 pages long. It was not a complicated machine. It probably could not be licensed and operated today.

The NRC has become so compartmentalized that most of the staff has no concept on how the powerplant as a whole functions but they can expound for hours on haw a little valve operates and might fail. If a new concept does hot contain that little valve it is declared unsafe even if it’s not required for operation of the system. The licensing and permitting process has to be reformed so that we can again build and operate demonstration facilities in a reasonable time frame. Even the DOE will not be able to build and operate a new system without an approved NRC license. DOE no longer has a reactor licensing capability and if they did it would be a worse process than that of the NRC. So I believe that regulatory reform is needed for us to rebuild our nuclear generating capacity.

7

EJ I have one further comment about SMR’s including the molten salt type. This has to do with the lifetime of the reactor. There is one SMR molten salt reactor design going through licensing. Fine, but the design does not accommodate change of the fuel, not even while on power. Instead the whole core of the reactor is replaced every ~seven years as a whole canister that starts off with ~2.5% enriched U and burns down until the fission products start absorbing too many neutrons from the depleting fissile U. I had originally thought that the fuel being liquid, fuel could be added via a side stream while fission products could be removed via chemical processing….not so for that design.

This is another one of my projects, some call them pet projects, that is to design the side stream chemical separation process to enhance the MSR, but again no traction there either. But if there is a grad student and/or a professor who are interested in pursuing this, my brain is available for picking.

I need to mention for example Bruce Power LLP, Bruce B, four units were started in the 1980’s, see here. And with refurbishment/component replacement they anticipate to be operational until year 2064, see here.

While small modular reactors including the molten salt and Thorium fuelled types may have their niche in say remote locations such as mines or as a heat and power unit on wheels, where there is population density requiring a dedicated power grid, the obvious choice will be GW sized units that can operate for 60 to maybe even 100 years will be the logical economy of scale vs say 100 of the 10MW SMR’s, or even 20 of the 50MW, or three of the BWRX 300’s .

I have doubts about $700 million covering the BWRX-300 reactor part given this is an estimate for a FOAK, and whether this includes all auxiliaries. Hopefully they have created a 100% validated Bill of Material and modelled the assembly costs in real time based on completed Civil, Mechanical, and P&ID work packages. As I said earlier, it is their $ they are risking, so they must not be wrong. See article here.

JK 2 Click here for an excellent article “The Element of Economic and Energy Policy Failure: Thorium and the Divergence of National Interests. Click here for essays, “Understanding the Larger Issues.”

KK 2 Click here for perspective of thorium nuclear power by expert in South Africa. Thorium can be placed into High Temperature Gas Reactor (HTGR) fuel such as the South African fabricated fuel ball but can also be placed into conventional metal fuel reactor assemblies. South Africa possesses the world’s richest thorium mine, Steenkampskraal.

8

JS The website, allaboutenergy.net supports wise use of fossil fuels and uranium and thorium nuclear energy. It is important that thorium based nuclear power be developed to verify its potential to help people everywhere. Given its additional safety features, it may be the best way to introduce nuclear to poorer countries. The United States could do this in exchange for benefits from those countries, like Russia and China are doing.

John Kutsch at Thorium Energy Alliance and Jim Kennedy at Th REE Consulting are doing excellent work for thorium nuclear energy and rare earth elements which come out of the ground together. They should be fully supported for national security.

Thorium and Rare Earth Elements for national security, help the whole world grow economically, have peace, protect the environment and preserve wildlife habitat.

9