thorium final project final rev

Thorium Reactors: Cleaner and Safer Nuclear Power ‐ NUC‐495 N.E.E.T. Capstone

Team Members: Austin Corazzin, Benjamin Smith, and Adam Wood

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Thorium Reactors: Cleaner and Safer Nuclear Power

An analysis of the viability and the controversy of Thorium

CAPSTONE PROJECT

Thorium Reactors: Cleaner and Safer Nuclear Power

Course – NUC-495 Nuclear Energy Engineering Technology Capstone




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TABLE OF CONTENTS

ABSTRACT…………………………………………………………………………………..…………….5

INTRODUCTION ...........................................................................................................................6

HISTORY OF NUCLEAR POWER ...........................................................................................7

Atom Exploration…..........................................................................................7

Fission and weaponizing ..............................................................................8

Creation of reactors and advancement…...............................................9

DISCOVERY OF THORIUM....................................................................................................10

Initial Discovery….........................................................................................10

Properties.........................................................................................................10

Availability…....................................................................................................11

INVENTION OF THORIUM REACTOR……………………………………………...…..…..12

First proposal of breeder reactor….......................................................12

Molten Salt Reactor Experiment.............................................................13

Molten Salt Reactor Program…................................................................13

INTRODUCTION TO MOLTEN SALT REACTORS………………………..….….…..….15

Background…...................................................................................................15

Function…..........................................................................................................15

Operation ……...................................................................................................16

THE RISE AND FALL OF THE MOLTEN SALT REACTOR PROGRAM……...…18

1953.....................................................................................................................18

1959.....................................................................................................................18

1965.....................................................................................................................18



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1969…………………………………………………………………….…………………18

EARLY PROJECTS UTILIZING THORIUM REACTORS……………….……………..20

Shippingport...................................................................................................20

Dragon...............................................................................................................21

Peach Bottom.................................................................................................22

Fort St Vrain....................................................................................................24

Arbeitsgemeinschaft Versuchsreaktor..........................................25

Thorium Hocktemperatur Reaktor................................................26

ADVANTAGES OF THORIUM FUELED REACTORS..................................................28

Costs...................................................................................................................28

Efficiency..........................................................................................................29

Safer....................................................................................................................30

Cleaner………………………………………………………………..……..……...30

DISADVANTAGES OF THORIUM FUELED REACTORS...........................................31

Slower Breeding............................................................................................31

Radioactive Waste........................................................................................31

Research and Development......................................................................31

THORIUM AS A BREEDER REACTOR…..........................................................................32

Nuclear Proliferation ..................................................................................32

Thorium Cycle ...............................................................................................33

How Thorium Works as a Breeder .......................................................33

Mixed Fuel System .......................................................................................34



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Use of Actinides and Waste Disposal ..................................................34

PROJECTS AROUND THE WORLD UTILIZING THORIUM .................................35

Why aren’t we using Thorium?..............................................................35

Canada ..............................................................................................................35

China .................................................................................................................36

Germany ..........................................................................................................36

India ..................................................................................................................37

Israel .................................................................................................................38

Norway ............................................................................................................38

United States .................................................................................................38

THE FUTURE OF THORIUM…………………………………………………………..….……40

Types of Reactors that can utilize Thorium.....................................40

Gas-Cooled Fast Reactors ........................................................................40

Lead-Cooled Fast Reactors ......................................................................41

Molten-Salt Reactors…………………………………………………….……41

NRC Advanced Reactor Licensing……………………………….……....41

CONCLUSIONS....................................................................................................…….………….43

ACKNOWLEDGMENTS .........................................................................................................44

REFERENCES .............................................................................................................................45

APPENDIX………………………………………………………………………...………...………….49



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ABSTRACT

Research on the use of Thorium as a viable source for nuclear energy production and the

controversy surrounding its use was conducted as a group comprising of Austin Corazzin,

Benjamin Smith, and Adam Wood. The group will be reviewing the history of the use of thorium as

a fuel source, how a thorium reactor operates, the advantages and disadvantages of thorium,

current research and development, and plans for the future.

As the nuclear power industry continues to grow we need to advance our technologies and

explore new options in reactor design. This includes looking at other fuel sources that are safer,

cleaner, and require little to no long term storage. Thorium can supply us with all these

desirable qualities and much more as we move forward.

This report is intended to demonstrate the achievement of all requirements for the Thomas

Edison State College Nuclear Energy Engineering Technology capstone course, to include the

ABET TAC criterion.



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Introduction

What is nuclear power? Currently nuclear power is the ability to harness a fission reaction

to produce electrical energy. In theory, a fusion reaction would also be a means of creating nuclear

power but there is currently no means of creating a stable fusion reaction (Hardy, 1999). There

have been tremendous advancements in the nuclear field and there are sure to be more. One of

these promising looking opportunities is the use of Thorium as a nuclear fuel. This could be just

another step in the future goal of limitless clean energy. In this paper we will discuss nuclear

history, the discovery of thorium, how thorium works, the advancement of thorium, and the future

possibilities of thorium applications.



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History of Nuclear Power

It is likely that one of the first true steps into the nuclear energy field is the discovery of

Uranium. The scientist Martin Klaproth first discovered this in 1789. Klaproth had actually

discovered an oxide of Uranium, while in 1841 Professor Eugène-Melchior Péligot was able to

isolate pure Uranium from Uranium Tetrachloride. Later in 1896 Henri Becquerel discovered

radioactivity by using a Uranium salt. He used this salt on a photographic plate and it caused an

area to darken. This led him to believe there was a form of invisible light created from this

Uranium. The darkening on this plate was due to the alpha and beta particles the Uranium was

emitting. Later that year, Paul Villard discovered gamma rays by using radium and finding that

there was a third type of penetrating radiation (Emsley, 2001).

In 1898 Marie Curie found that Thorium was radioactive. She and her husband Pierre were

also able to extract polonium and radium from an ore. Then in 1902 Ernest Rutherford discovered

that elements decay based on the observation that every time an element gave up an alpha or beta

particle it would turn into a new element. The next big step towards gaining nuclear energy took

place in 1938. Otto Hahn and Fritz Strassmann were able to continue experiments created by

Enrico Fermi to prove that they were able to produce a fission reaction by splitting an atom. In

1939 Lise Meitner, Otto Frisch, and Niels Bohr were able to calculate the energy released from this

atomic reaction. This showed that there was a huge potential for this type of energy and also

provided some of the first proof of Einstein’s E=mc2 theory (Emsley, 2001).

After these discoveries, the next step was to develop a means of harnessing this newfound

nuclear reaction. Otto Hahn and Fritz Strassmann were able to show that as well as producing

massive amounts of energy, this fission process also provides release of extra neutrons which in



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turn would be capable of causing a chain fission reaction. Neils Bohr was then able to determine

that the isotope U-235 would be more likely to provide a fission reaction than U-238. The issue

here is that U-235 made less than 1% of the uranium while U-238 made up over 99%. This led to

an enrichment process to provide a high concentration of U-235 (Hardy, 1999). In 1939, Francis

Perrin came up with the critical mass concept. This concept explains that there is a specific amount

of U-235 needed in order to cause a self-sustaining chain fission reaction.

In the early 1940s the US began the Manhattan project to turn this into a weapon during

World War II. The Americans were working on multiple different ways to enrich both U-235 and

Pu-239. Scientist Robert Oppenheimer led a team at Los Alamos in producing the world’s first

atomic bombs with the goal of having them produced by mid-1945. They were able to perform the

first atomic test with Pu-239, which turned out successful. With this test complete, they felt there

was no need to test a bomb with U-235 since it was a more simple design. There were two atomic

bombs produced at this point, one containing U-235 and one containing Pu-239. On August 6,

1945, the first bomb was dropped on Hiroshima that was made from U-235. 3 days Later the Pu-

239 bomb was dropped on Nagasaki and Japan surrendered the following day. While many other

countries have since developed nuclear weapons, these were the only 2 nuclear attacks carried out

in history.

In 1946 Alvin Weinberg and Forrest Murray wrote a paper detailing the ideas for the

world’s first light water nuclear reactor. In 1951 the Experimental Breeder reactor was the first

reactor used to produce electricity. Also in this year, congress announced construction of the first

nuclear submarine. Throughout the 1950s, many nuclear arms agreements were made and much

more progress was made with harnessing nuclear energy. In 1957 the first commercial



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pressurized water reactor was completed. During the next two decades, multiple reactor designs

were thought up and implemented (Hardy, 1999). As of today about 60% of the world’s reactors

are pressurized water reactors and about 20% are boiling water reactors which leave the rest as a

combination of the many other designs. After a decline in nuclear power plant production from the

1970s to around 2000, many countries are starting to build more reactors in an attempt to try and

convert to a clean energy.



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Discovery of Thorium

Going back in time, we will take a look at the origins of Thorium. In 1828 Swedish scientist

Jöns Jakob Berzelius received a mineral as a gift that contained an unknown substance. He then

determined that this substance was an unknown element at the time, which he named Thorium,

after Thor, the god of war. He had reused the name Thorium for what he mistook as a new element

in 1815 that turned out to be an yttrium mineral. When he published his work in 1829 he gave the

mineral that held the thorium, the name Thorite (The Element Thorium, n.d.).

In 1898 Marie Curie discovered that Thorium was radioactive. A few years later Ernest

Rutherford was able to measure the decay rate of Thorium (Emsley, 2001). This allowed for the

identification of Thorium’s half-life of about 14 billion years.

Thorium is in the actinide family and has the atomic number 90. Since thorium is

radioactive and its physical properties are similar to lead, there are very few commercial

applications of this element. One of the reasons thorium is thought to be a potential source of

power if the fact that it can be used to breed nuclear fuel. Uranium ore usually consists of U-235, U-

238, and U-239. The downside of this is that U-235 is the only one of these isotopes that is

fissionable. Less than 1% of this concentration is U-235. Where thorium comes into play is the fact

that it can produce U-233. U-233 is known to be a fissionable isotope of Uranium but is not found

naturally occurring on earth. When Th-232 is bombarded with neutrons, it then changes in stages

from thorium-232 to thorium-233, to protactinium-233, and finally to uranium-233. This process

takes approximately a month to perform but due to the long half-life of U-233, once it is created, it

is there to stay until used. The biggest challenge with this is being able to economically produce U-

233 on a large scale.



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One may ask the question, how do you get access to thorium? That has a fairly simple

answer because of the abundance of thorium. Thorium is a relatively abundant element on earth. It

is estimated to form 15 ppm of the earth’s crust. It is located in thorite, monazite, and some other

minerals (Emsley, 2001). In order to pull thorium from minerals, a chemical process needs to take

place. First the mineral needs to be oxidized in order to form Thorium dioxide (ThO2). After the

ThO2 is extracted, it is to be heated with calcium in order to pull out the pure thorium (Banks,

1953).

As previously stated there are few commercial uses for thorium. The most common use is in

gas lantern mantles. The reason behind this is that thorium has a very high melting point. When

the gas is passed through the mantle and burned off, it allows the mantle to glow extremely bright

without burning up or melting. The radioactivity in these mantles is so small that it poses

practically no threat to humans. A few other things thorium is used for include use in high

temperature ceramic, use as a catalyst, and it is also used in some glass production (Emsley, 2001).

While there has still been little success using thorium large scale as a means of nuclear energy,

there is still hope that someday soon there will be a breakthrough for a large-scale thorium

breeder reactor.



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Invention of Thorium Reactor

In April of 1946, A.W. Weinberg along with P.H. Murray published a paper by the name of

High Pressure Water as a Heat Transfer Medium in Nuclear Power Plants. This was a really

innovative idea at the time, which described and was effectively the precursor to today’s modern

light water pressurized water reactors. In their preliminary findings they go on to state, “… facts

suggest that a high pressure water power plant may be built with less development work than

either the gas or liquid metal plants, and that such a plant might be very reliable.” This was an

incredibly insightful view, which would end up being more energy efficient and cost effective than

current models at the time. They continue on to state the main reason for their idea to use a

pressurized water reactor is that it will most likely be the medium that must be used to create a

successful breeding reactor (Weinberg & Murray, 1946).

The next thing they go on to discuss in this paper is the use of an evaporator or flash

chamber for the system to create steam. They determined that it would be necessary to use a

condenser for the case because flashing the water could cause intensely radioactive steam to hit

the turbine. This has in turn, become the most common nuclear plant design in use today.

One thing that Weinberg and Murray pushed further in this paper and had hopes to design

was the use of Thorium to create a self-sustaining light water reactor. Their idea was that as much

thorium was produced as was used in the process. This was an interesting idea that proved

fruitless for the pair. Weinberg was eventually awarded a patent for pressurized water reactors

but the advancement of a Thorium breeder reactor would be put on hold for many years.

In the early 1950s, the government tried to develop a nuclear reactor capable of powering

military planes. In theory, this would give you near unlimited flight time without having to go back



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and refuel. For this project they started a program to test the validity of creating a molten salt

reactor for use on these aircraft. This project was the precursor for the molten salt reactor

experiment, or MSRE (Hardy, 1999). In 1956, Alvin Weinberg was still on the scene and requested

that the molten salt reactor designs be researched further for civilian use. He was able to get

approval for civilian use and gained funding for Oak Ridge National Laboratory. In 1959, the

Atomic Energy Commission met to determine which reactor concept should be used and the

molten salt reactor with thorium breeding is the model that was chosen. They felt that this model

held the highest chance of being successful. The next year, Oak Ridge proposes their design to the

Atomic Energy Commission. This model would use graphite as the moderator and lithium and

beryllium as solvents. The Atomic Energy Commission accepted the proposal and the design

process began (Hardy, 1999).

In 1965, the Molten Salt Reactor Experiment completed their build without the use of

thorium. Towards the end of the year, they were able to achieve criticality but were limited on

power output while testing different materials. Part of their interest at this point was using their

thorium-lithium-beryllium mixtures to test responses for breeding. At the start of the New Year in

1966, MSRE was able to bring their reactor into the MW power range. Testing of different

components and materials would continue throughout the next few years. In March of 1968, they

stopped using U-235 and switched over to U-233, which had been bred from Th-232. This was the

first time U-233 had ever been used to achieve criticality in a nuclear reactor. Unfortunately in

1969, due to budget problems, the project was getting shut down (Hardy).

While the Molten Salt Reactor Experiment had been shut down, the Molten Salt Reactor

Program continued running and had their foot in the door with several different projects, many of



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which we will get to later. One of the major projects they were involved with was the Shippingport

Atomic Power Station in Pennsylvania. This was the first commercial nuclear power plant in the

United States. The first two reactor cores built at Shippingport were very similar in the fact that

they were both pressurized water reactors that used U-235 with a blanket of U-238 (Clayton,

1993).

The third core however, was an experimental, thermal breeder reactor, which used U-233

as the seed, and thorium as the blanket (Kasten, 1998). Due to thorium’s fissile properties, it was

able to convert into U-233 during its cycle. This experimental reactor went critical in 1977 and

reached full power in the same year. This core operated for 5 years with the capability of operating

at 60 MWe. During this time period it produced over 2 billion kilowatt-hours of power. At the end

of this five-year period, the core was shut down and removed and decommissioned. It was

discovered that there was 1.4% more nuclear fuel than when they had started (Clayton, 1993).

This proved to have been the first and only successful breeder reactor using a light water

pressurized water reactor.

The downside to all of this was that due to multiple factors including political and financial

reasons, the government was far too focused on using liquid-metal fast breeder reactors. With

their focus in other areas, budgets were cut and projects were cancelled, even with promising

results (Hardy, 1999). This helps to explain the gap between then and now with the lack of funding

towards the promising fuel.



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Introduction to Molten Salt Reactors

Reiterating some of what has already been said; molten salt reactors were developed in the

1960s as an efficient option for nuclear power. The Molten Salt Reactor Program, which oversaw

all the projects, existed from 1957 until 1976. They key experiment this program attempted was

the molten salt reactor experiment, which operated from 1965 to 1969. During the first three

years of this program it was strictly a molten salt reactor using U-235 and U-238 as the fuel and

lithium fluoride, beryllium fluoride and zirconium fluoride as the salts. This used uranium

tetrafluoride enriched to 33% within the salt to complete the composition. The fuel makeup of this

solution was less than 1% (The Use of Thorium, 1969).

After finishing this first phase, the second phase took aim at using U-233 as a fuel with

thorium used a blanket to act as a breeder reactor (Clayton, 1993). This experiment was short-

lived but moderately successful. It had a few issues that would have to be worked out if any further

experimentation were to be performed. There had been an excess creation of tritium in the

secondary loop, which poses radioactive release concern in a large reactor. Another issue they ran

into was the fact that there was some chemical corrosion and neutron embrittlement of the reactor

vessel due to the alloy used in its construction (Clayton, 1993). Throughout this experiment there

were ways found to counteract the issues they had run into and resolved all the major issues. It can

be difficult to tell what issues may come up on a large scale versus having just one experimental

reactor.

Here we will go into slightly more depth on the function of a molten salt reactor while

keeping in mind the molten salt reactor experiment. In the typical molten salt reactor design, there

is a molten mixture containing the uranium tetrafluoride and lithium and beryllium salts. This is



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what acts as the fuel. The moderator is basic graphite in the core (MacPherson, 1958). This helps

the salt maintain an operating temperature around 700oC and maintains a low operating pressure.

Much higher temperatures are theoretically possible but have never been tested (Kasten, 1998).

The secondary loop is another salt loop which is used as a heat transfer medium to convey heat to

a third loop to produce steam.

Since the fuel in a molten salt reactor is technically in liquid form, thorium may be mixed in

with the uranium to create what is called a homogenous mixture. If there are two fluids in separate

loops, each containing a salt while one is mixed with uranium and the other with thorium; it is

known as a heterogeneous design. This design can be used as a breeder reactor by removing the U-

233 that is created from the thorium in the second loop and placing into the first loop. The limiting

factor in this case is caused by the degradation of the graphite moderator due to neutron flux.

Any fissile products created during the reaction are being constantly removed and replaced

by other fission products. Unwanted products such as tritium and xenon are dealt with by

removing them from the system. A trouble-causing isotope is protactinium-233. It is one of the

decay products as thorium decays towards U-233. Protactinium causes problems due to its ability

to act as a neutron absorber before it decays. Since the fission products are being continuously

pulled from the system, it allows for a higher burn rate and the waste created is all fission products

and not fuel. This allows the waste to have much shorter radioactive lives (Kasten, 1998).

Molten salt reactors, like pressurized water reactors, have a negative temperature

coefficient of reactivity. This means that if power gets out of control and heats up too much, it will

shut itself down. This also keeps power from increasing too rapidly in the case of any control

mishaps.



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One reason behind using fluoride salts is their ability to transfer heat. Their heat transfer

coefficient is higher than that of water. Other reasons include: that they are not damaged by

radiation, do not react with water or air, and are fairly inert. The difference between the lithium

and beryllium is that the beryllium is toxic but can be kept at lower temperatures than lithium.

Lithium can also contain more uranium, thus allowing the uranium to be less enriched. Lithium

also must have certain isotopes used for the fact that some of theirs cause an overabundance of

tritium to be produced (Kasten, 1998). This should help to understand the basic function and

operation of molten salt reactors.



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The rise and fall of the Molten Salt Reactor Program

In 1953 the United States Air Force had a desire to develop a nuclear powered long-range

bomber. Several years and about $1 billion were drained into the program in this pursuit. The

program had been unable to successfully sustain a flight utilizing a nuclear reactor. Several reactor

designs were developed in the pursuit of a high temperature reactor to run the jet propulsion. Oak

Ridge worked towards solving the issue of a reactor to meet the needs of operating at a high

temperature and low pressure. One of the reactor designs that were promising was based on a

liquid fluoride fuel source. The Aircraft Reactor Experiment led to vast amounts of research and

development of salts and reactor design.

In 1959, Oak Ridge National Laboratories was granted 4 million dollars for the

development of a liquid fuel reactor. For the next three years the scientists focused on how it

would be designed. It wasn’t until 1962 that construction would begin. On June 1st 1965 the MSRE

achieved criticality. October 1968, MSRE was the first reactor to operate on U-233.

In January 1969 the fuel was switched to U-233 and the MSRE is operated at full power

on U-233. On December 12, 1969 the MSRE was permanently shut down; thus allowing allocated

funds to support other projects. Finally in 1973 the AEC had the ORNL terminate the Molten Salt

Reactor Project. In 1974 ORNL resumes research, only to be told in 1975 to end all work on the

molten salt reactor due to the budget. In February 1976, the Energy Research and Development

Administration ordered the ORNL to terminate the MSRE due to the budget.

In all the Molten Salt Reactor ran from 1965 – 1969. While it was a proven and viable

technology, it was not a priority. At the time the nation wanted a nuclear reactor that could be

used in a submarine and for creation of nuclear warheads to win the arms race. While the



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technology could have been developed further for use in a submarine, the technology was already

readily available to implement into the submarines. Furthermore, Thorium’s capability of

producing Plutonium for use in a nuclear weapons was not a viable option.



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Early Projects Utilizing Thorium ReactorsSO3(a-c)

Another Pressurized Water Reactor project spearheaded by the Navy’s Admiral Hyman G.

Rickover was the Shippingport breeder reactor. It was designed to have an interchangeable core

and test various fuels (Kasten, 1998). Shippingport was located where the Beaver Valley Nuclear

Generating Station is now located in Beaver County, Pennsylvania. It was fitted with a light water

moderated, thermal breeder reactor. Its third core design utilized a Uranium seed and thorium

blanket design (Kasten, 1998).

The seed and blanket design also known as the Radkowsky Thorium Reactor (RTR) was

created by Alvin Radkowsky who was the reactor designer for the Navy’s nuclear powered

submarines and air craft carriers (Kasten, 1998). Thorium is unable to sustain a fissile chain

reaction by itself and as such needs an external neutron source. The solution was to use another

fissile material, which in this case was Uranium. Thus by causing several more probabilities of

collisions and reactions with the spare neutrons from the fission of uranium. Radkwosky created

clusters of “seeds” which are fuel rods made up of uranium and zirconium and enveloped them in

“blankets” which are rods made of thorium oxide pellets. By this process there would be much less

radioactive waste (Kasten, 1998). Another great benefit was that a seed could be made up of old

nuclear weapons grade plutonium and the thorium could create electricity and dispose of the

nuclear waste (Kasten, 1998).

Radkowsky wanted to see the implementation of thorium reactors in the Navy’s aircraft

carriers and submarines but alas he had no support. This man has made a tremendous

contribution to society and the design of nuclear reactors (Allen, 2009). A great deal of thanks is in

order for this man. He passed away in 2002 with pneumonia. The seed and blanket design is an

amazing demonstration of the capabilities of thorium but it will most likely not be utilized for



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commercial use because of its extremely high costs (Allen, 2009). The seeds were metallic vice

oxide ceramic meaning that they could melt and release radioactivity much more quickly during a

reactor accident. It is because of these reasons that Radkowsky’s design is not viable. (Allen, 2009)

High Temperature Gas Reactors

The Dragon reactor was built in Winfrith, UK. It was designed as a test reactor for the

High Temperature Reactor program in Europe. It was operated from 1964 to 1975. The

objectives of the Dragon reactor were to test fuel, fuel elements, and structural materials. The

Dragon reactor was capable of producing 20MW of electricity. It used helium as its primary

coolant with an inlet and outlet reactor temperature of 350°C and 750°C (Beck, 2011). The core

was a prismatic block design. This means the core was designed with prismatic graphite blocks

and the fuel was initially loaded with highly enriched uranium and Thorium (Beck, 2011). Due to

concerns of rarity of highly enriched uranium it was later changed to lowly enriched uranium.

SO7.e

(Beck, 2011)



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Peach Bottom Unit 1 was the first High Temperature Gas Reactor built in the US. It was

owned and operated by the Philadelphia Electric Company. It was operational from 1966 to 1974.

The reactor was capable of producing 40 MW of electricity (Beck, 2011). It used helium as its

primary coolant and graphite as its moderator. Its cold leg temperature was 327°C and the hot leg

temperature was 700°C (Beck, 2011). The fuels comprised of uranium and thorium carbides in a

prismatic form and were coated with a layer of pyrolytic carbon (General Atomics, 2004). The

pyrolytic carbon is essential a miniature containment vessel. It was later determined that this was

insufficient and was replaced with BISO coated fuel (Beck, 2011). Which has two layers of

ceramics to act as a buffer of recoiling fission products and retain noble fission gasses. This

worked for a while but would fail at higher temperatures. Finally a layer of silicon carbide was

added which is now known as TRISO fuel. It was closed because it completed its objective of

demonstration and was considered not economically viable due to its small size. Below you can

see what the TRISO particle is composed of.

(Beck, 2011) (General Atomics, 2004)



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The Fort St. Vrain (FSV) reactor was a High Temperature Gas Reactor designed by General

Atomics. It was located in Platteville, CO. It was operational from 1974 to 1989. The reactor was

capable of producing 330 MW of electricity (Beck, 2011). The core used helium as its primary

coolant. The helium produced superheated and reheated steam at 538°C (Beck, 2011). The

reactor’s cold leg temperature was 404°C and the hot leg temperature was 777°C (Beck, 2011).

The reactor was inside of a pre-stressed concrete reactor vessel. It had a prismatic block design

for the core. The fuel was comprised of carbides of uranium and thorium with TRISO coatings

(Beck, 2011).

(Beck, 2011)



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Arbeitsgemeinschaft Versuchsreaktor (AVR) was one of the first nuclear reactors in the

Federal Republic of Germany. It was an experimental station utilizing pebble-bed reactors used to

test fuels. It was operational from 1967 to 1988 (Beck, 2011). It was able to produce 15 MW of

electricity. It used helium as its primary coolant and graphite as its moderator. Its cold leg

temperature was operated at 275°C and hot leg temperature was operated at 950°C (Beck, 2011).

Its fuel was comprised of uranium and thorium oxides with a BISO coating (Beck, 2011).

Farrington Daniels theorized the pebble-bed reactor in 1947 (ORNL Review, 2003). The

premise is that helium would rise through fissioning uranium oxide or carbide pebbles and cool

them by carrying away heat to a heat exchanger to generate electricity (ORNL Review, 2003). The

pebbles are roughly the size of tennis balls and are made of pyrolytic graphite, which acts as the

moderator. Within the graphite are several thousands of TRISO particles (Beck, 2011). In this

design thousands of pebbles are piled up to create the reactor core and thus cooled by a gas, which

is chemically inert with the fuel element (Beck, 2011).

(Beck, 2011)



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Thorium Hocktemperatur Reaktor was another HTGR experiment in Germany. The

Federal Republic of Germany and Nordrhein Westfalen sponsored the THTR power plant (Beck,

2011). It was operational from 1985 to 1989 (Beck, 2011). It was capable of producing 300 MW of

electricity. It used helium as its primary coolant and graphite as its moderator. Cold leg

temperature operated at 250°C and hot leg temperature operated at 750°C (Beck, 2011). Its fuel

was comprised of uranium and thorium oxides formed into TRISO particles. Its reactor was

housed in a pre-stressed concrete reactor vessel. The THTR demonstrated inherent safety features

of HTGRs including core and plant transient data (Beck, 2011).

(Senan, 2013)



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ADVANTAGES OF THORIUM FUELED REACTORSSO4a,b

First and foremost, as with anything, the top priority when it comes to utilities is financial

in nature. There are several ways in which thorium makes better economic sense. Thorium

reactors will be cheaper, safer, and cleaner than the current commercial nuclear reactors using U-

235.

There is a much higher abundance of naturally occurring thorium deposits throughout the

world; for example, it is about as abundant as lead is and roughly three times more abundant than

tin. There is roughly six parts per million in an average soil sample (ATSDR, 1990). In a cubic

meter of soil anywhere in the world you can extract an amount equivalent to about three M&Ms or

6 grams (Towell, 2015). Given the fact of how abundant thorium is it drives the point to make

alliteration to how much more energy can be produced from it. It has been claimed that Thorium

produces 250 times more energy per unit of weight (Towell, 2015).

Another cost effective utilization is the use of radioactive isotopes. Being that it is from a

liquid fuel the isotopes can be removed chemically from the liquid. Compared to the solid fuel

reactors where these medical grade isotopes are locked into the radioactive waste entrapped with

the unspent fuel, and other radioactive byproducts. So with this capability the nuclear facility can

amass more revenue through sales of highly needed isotopes to fight cancer and tumors around

the world. SO10.c

Medical isotopes that are of interests are Thorium – 229, Actinium – 225, Astatine – 211,

Lead – 212, and Radium – 223 (Duchemin, 2015). Thorium -229 can decay into Bismuth - 213

which is an alpha emitter used to fight leukemia, cancers, and tumors (Duchemin, 2015). Bi-213

has a half-life of 45 minutes and decays with the emission of an alpha particle (Duchemin, 2015).

Actinium 225 is formed from the radioactive decay of Radium – 225 which is the decay product of



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Thorium – 229. Actinium is used against acute myelogenous leukemia (Duchemin, 2015). Astatine

– 211 has been used for adjuvant therapy after surgery for brain tumors. Lead – 212 peptides can

effectively target and destroy fast spreading cancer metastases that are difficult to treat by

surgery, chemotherapy, or external beam radiation therapy (Duchemin, 2015). Radium – 223 has

a half-life of 11 days and it produces four short lived decay daughters that will cascade into four

alpha emitters (Duchemin, 2015). Radium – 223 is useful for treating bone cancer metastases in

the skeleton that result from advanced prostate and breast cancer (Duchemin, 2015).

Thorium nuclear facilities will be cheaper to build than other power plants capable of

producing the same output. Thorium reactors can be operated around atmospheric or slightly

above atmospheric pressures (Peterson, 2003). Therefore, will not require a pressure rated;

reactor vessel, piping, or containment dome. Less equipment will be required to operate the

facility as well (Sorensen, 2011). Will not require a large real estate footprint and the equipment

can be built much smaller. Thus all the resources normally allocated for construction can be better

utilized to provide a reliable and full energy source for the population needs. Another great safety

feature is the freeze plug (Sorensen, 2011). If there is a reactor casualty the plug will lose cooling

and melt thus draining the fuel into a holding tank. Once in the fuel is in the holding tank all fission

will begin to cease and radioactivity reduces (Sorensen, 2011). These features allow for a walk

away safe reactor. With no operators to monitor and control the reactor there is no concern for

meltdown and release of fission products to the atmosphere.SO1.b, SO1.c

The thorium reactor is efficient in the means by which it uses its fuel. Thorium breeds U-

233 more efficiently than U-238 into plutonium, due to the fact that less nonfissile isotopes are

generated (Kazimi, 2003). Thorium dioxide is about 10 -15% more thermally conductive than

uranium dioxide, meaning a higher rate of heat transfer from fuel into the primary coolant



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(Kazimi, 2003). The thorium fuel cycle can be seen in the example below.

As you can see from the illustrations, the Th-232 is continually converted into U-233 allowing for

clean renewable energy. SO1.a

The other great attribute of thorium is the ability to recycle all of its fuel sources and

byproducts. By the time the reactor has used up all of its radioactive byproducts the nuclear waste

generated will be a fraction of the amount compared with conventional nuclear reactors (Kazimi,

2003). Nearly all Thorium fuel is burned into useful energy as compared to 0.5% of Uranium

(Sorensen, 2011). It takes roughly 90 to 100 tons of Uranium to produce the same amount of

energy as 1 ton of Thorium (Sorensen, 2011). In a thorium reactor Xenon and other burnable

poisons can be continuously removed. Therefore, with minimal waste and short lived fission

products the debacle of what to do with nuclear waste can be solved.



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Thorium 232 is inherently safe as opposed to U-235. Th-232 is not fissile; meaning no

matter how much thorium is thrown in together it will not create a reaction. It will only create a

reaction when it is introduced to a neutron. If the chain reaction is to be stopped, it is as simple as

stopping the neutron source. Also the waste by product is produced at a much smaller scale than

with Uranium. The thorium reactor doesn’t produce plutonium that can be used in nuclear

weapons and produces less long-lived radionuclides than uranium reactors. (Kazimi, 2003). An

operating thorium reactor produces fewer actinides and transuranic elements. An actinide is an

element of major radiotoxic concern in long term storage of nuclear wastes.

Lastly, Thorium can generate energy without the risk of nuclear weapons proliferation

(Kazimi, 2003). After 10 years of storage about 83% of thorium waste is stable (IAEA, 2005). The

remaining material requires 300 years of storage as compared to 100s of thousands of years for

Uranium waste storage. Thorium produces 3000 times less Plutonium than Uranium fuels (IAEA,

2005). The Plutonium that is produced is too hot to create a nuclear bomb and will be

accompanied by Thallium – 208 which is a high gamma emitter known to damage electronic

circuits. Thorium reactors are able to destroy and convert energy from civilian and weapons grade

plutonium at a rate of 1000kg per GW year (IAEA, 2005).



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Disadvantages of Thorium Fueled Rectors

The fact that Th-232 is not fissile is a disadvantage in the fact that it requires an external

neutron source. The rate at which Th-232 is converted into U-233 is a rather long process. The

process is as follows: Th-232 interacts with a neutron thus becoming Th-233, which has a half-life

of 22 minutes thus transmuting into Pa-233. Pa-233 has a half-life of 27 days in which case it

undergoes a beta minus decay to U-233. For a single neutron to create a sustainable chain reaction

it would be roughly 27days before an appropriate amount of fission can occur to sustain power

production. If the neutron sources were to not interact ideally it could end the chain reaction thus

necessitating another 27day wait.

Thorium may produce less radioactive waste than the uranium reactor but at the end of the

day it is still radioactive waste. It is known that a Thorium reactor produces 0.0438 – 0.6725 kg

of minor actinides per MW year and none while shutdown. While a Uranium reactor produces 0.54

kg of minor actinides per MW year and 0.43 kg of minor actinides while shutdown. Therefore it

becomes quite evident that Uranium produces about 10 to 100 times more minor actinides than

Thorium. While some of the radioactive waste is diverted to medical use there is still a need to find

a long-term solution to dispose of waste appropriately. The left over fission products from a

Thorium reactor have an expected half-life of about 700 years.

Research and development of creating an efficient and cost viable option for a thorium

based reactor is lacking. While there have been many experimental reactors none of them have

proved to be economically viable. As such there are several years and millions of dollars that need

to be used to further develop this technology, which a lot of investors don’t see the value in. It is

increasingly difficult to receive backing in this project, as it seems to be chasing after the wind.SO10.d



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Thorium as a Breeder Reactor

We have all heard of breeder reactors, but what does the term breeder reactor actually

mean? A breeder reactor is one in which more fissile material is generated than is used. It seems

like breeder reactors are constantly in the news, especially with the recent discussions on

developing countries nuclear programs, such as Iran. Nuclear proliferation has been a big topic

these days within the United Nations and under the Obama administration. Breeder reactors can

be used to produce weapons grade plutonium or uranium, that is the natural byproducts of the

fission process and neutron absorption creates radioactive materials that can be used in nuclear

weapons.

Not all breeder reactors produce materials for nuclear weapons. It is difficult to make a

practical nuclear bomb from a thorium reactor's byproducts. According to Alvin Radkowsky,

designer of the world's first full-scale atomic electric power plant, "A thorium reactor's plutonium

production rate would be less than 2 percent of that of a standard reactor, and the plutonium's

isotopic content would make it unsuitable for a nuclear detonation" (Chang 2002).

Thorium reactors naturally function as a type of breeder reactor that produces usable fuel

for future nuclear power generation. In the thorium cycle, fuel is formed when Th-232 captures a

neutron to become Th-233. This normally emits an electron and an anti-neutrino by β−

decay to

become Pa-233. The process continues as another electron and anti-neutrino are emitted by a

second β−

decay to become U-233: SO2

.

http://en.wikipedia.org/wiki/Neutron_capture



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To understand the importance of this we must first look at how the nuclear reaction

is started in a thorium reactor. Unlike natural uranium, natural thorium contains only trace

amounts of fissile material (such as Th-231), which are insufficient to initiate a nuclear chain

reaction. This requires the addition of some other fissile material, which means another neutron

source is necessary to initiate the fuel cycle for a sustained neutron reaction. The only fissile

options for a thorium reactor are U-233, U-235 or Pu-239, all of which are difficult to supply.

Thermal breeding with thorium requires that the neutron population in the reactor be very high.

This requires that there is a low amount of neutron leakage and a low amount of resonance

absorption. This can be attained by the use of a reflector to scatter neutrons back into the

reactor, resulting in lower net neutron losses, which is a feature common to most uranium fueled

reactors. The cross section for absorption in Thorium is much smaller than that of Uranium and

will therefore have fewer occurrences of resonance absorption. In addition fissile material can be

bread using slow neutrons, which also tends to result in less neutron leakage due to the shorter

thermal diffusion length resulting in a higher neutron population within the reactor. These three

things combined lead to the ability of a thorium-fueled reactor to function as a breeder reactor.

The possibility to breed fissile material in slow neutron systems is a unique feature for thorium-

based fuels and is not possible with uranium fuels.

Another distinct option for using thorium is as a ‘fertile matrix’ for fuels containing

plutonium that serves as the fissile driver while being consumed (and even other transuranic

elements like americium.)

In a thorium-fueled reactor, Th-232 absorbs neutrons which will produce U-233. This is

very similar to the process in uranium breeder reactors where fertile U-238 absorbs neutrons to



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form fissile Pu-239. Depending on the design of the reactor and fuel cycle, the generated U-233

can remain in the reactor and can fission to produce energy, or it can be chemically separated from

the used nuclear fuel and formed into new nuclear fuel.

This would result in a mixed fuel system. In this system reactor operators would allow a

batch of fuel rods to stay in a reactor for about five years, roughly the same as with current reactor

designs utilizing uranium fuel. The fuel would then be allowed to cool for a few years while the

shorter-lived fission products decay, and would then be reprocessed over another year, mixing

actinide wastes with more thorium before being put back in a reactor.

This almost entirely eliminates the need for any new fissile material to be added to start the

neutron chain reaction and thus relies entirely on thorium. It also solves the problem of storage

of nuclear waste in more way than one: It produces little to no waste that requires years of long

term storage and it can actually use some of that waste that is currently being stored around the

world as it slowly decays. There are approximately 430 operational reactors in the world that

require disposal of waste. With the closing of the Yucca Mountain waste site project the United

States is struggling to find places to store our spent material, as well as the United Kingdom.

Mixing nuclear waste and actinides with thorium could eliminate long-term waste storage.



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Projects Around the World Utilizing Thorium

With all of the benefits and abundance of thorium why aren’t we currently using it as a fuel

source for our nuclear power needs? The United States built an experimental molten salt reactor

using U-233 fuel by bombarding thorium with neutrons at Oak Ridge National Laboratory that

operated critical from 1965 to 1969 for almost 15000 hours.

We know it can work. Is it possible that the industry has reasons for not using it? Or

maybe we just don’t know about it? Despite the documented history of thorium nuclear power,

many of today’s nuclear experts were nonetheless unaware of it. According to Chemical &

Engineering News, "most people—including scientists—have hardly heard of the heavy-metal

element and know little about it...,it's possible to have a Ph.D. in nuclear reactor technology and not

know about thorium energy." says nuclear physicist Victor J. Stenger who first learned of it in

2012. “It came as a surprise to me to learn recently that such an alternative has been available to

us since World War II, but not pursued because it lacked weapons applications.” (Stenger 2012).

Current projects:

Research and development of thorium-based nuclear reactors, primarily the Liquid fluoride

thorium reactor using the molten salt reactor design that was successful in the 1960’s, has been or

is now being done in Canada, China, Germany, India, Israel, Norway, and the United States.

Canada

Canada Deuterium Uranium (CANDU) reactors are capable of using thorium, and Thorium

Power Canada has planned and proposed developing thorium power projects for Chile and

Indonesia. In Chile the proposed thorium fueled plant would be a 10 MW reactor. This reactor is



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for testing purposes and would not supply power to a power grid, but could be used to power a

2000-liter per day desalination plant. Thorium Power Canada is developing a 25 MW thorium

reactor in Indonesia, which will be capable of providing electrical power to the country’s power

grid.

China

China has a need for nuclear power that is clean, safe, and readily available not due to their

rising energy demands, but rather the smog problem that is prevalent due to their large reliance

on coal for current energy production. They have partnered with CANDU and Oak Ridge National

Laboratory for research and development and plan on devoting a large number of man-hours and

four hundred million dollars to the project over the next ten years in hope of building a working

plant of the molten salt reactor type using thorium and uranium as fuel within this time frame.

Germany

Germany built a prototype reactor called the Thorium High Temperature Reactor (THTR-

300) that used thorium as a fertile fuel and highly enriched uranium U-235 as the fissile fuel,

although mostly U-235 was fissioned. The THTR-300 was a helium-cooled high-temperature

reactor with a pebble-bed reactor core with particles of uranium-235 and thorium-232 fuel

embedded in a graphite matrix. It fed power to Germany's grid for 432 days in the late 1980s,

before it was shut down for cost, mechanical and other reasons. Germany is currently looking into

building a reactor of similar design but on a much larger scale that will utilize thorium as it’s

primary fuel source.



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India

India has very little and very poor quality uranium ore deposits available but has an

abundance of thorium. The Bhabha Atomic Research Center has proposed their next generation

nuclear reactor using thorium, as it’s primary fuel source. They plan to have this reactor built by

2016. They estimate that because of the inherent safety associated with thorium reactors that

the reactor could operate safely for at least 120 days with no operator oversight. Because of the

safety that these reactors present India expects that thorium reactors will be built in populated

cities such as Mumbai or Delhi.

“India's government is also developing up to 62, mostly thorium reactors, which it expects

to be operational by 2025. It is the "only country in the world with a detailed, funded, government-

approved plan" to focus on thorium-based nuclear power. The country currently gets under 2% of

its electricity from nuclear power, with the rest coming from coal (60%), hydroelectricity (16%),

other renewable sources (12%) and natural gas (9%). It expects to produce around 25% of its

electricity from nuclear power. In 2009 the chairman of the Indian Atomic Energy Commission

said that India has a "long-term objective goal of becoming energy-independent based on its vast

thorium resources." (Pham 2009).

India's first commercial fast breeder reactor, the 500 MW Prototype Fast Breeder Reactor

(PFBR), is approaching completion at the Indira Gandhi Centre for Atomic Research. The goal is to

use thorium 232 to breed uranium 235 using plutonium as the fissile starting source. Once it is

operating critical and neutron absorption creates uranium 235, the thorium will be the only fuel

material required in the core.



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Israel

Researchers from Ben-Gurion University in Israel and Brookhaven National Laboratory in

New York began to collaborate on the development of thorium reactors, with the intent of being

self-sustaining, meaning that it will produce and consume approximately the same amount of fuel.

Norway

Norway’s privately owned Thor Energy partnered with Westinghouse to start a four-year

trial of an existing reactor that will be fueled with Thorium. Norway is also currently developing

an accelerator driven reactor-using thorium as the fuel. This brings about two concepts not

currently employed in commercial nuclear power generation: The first being the use of thorium

as a fuel, and the second being the accelerator driven reactor. In an accelerator driven reactor a

high-energy beam directs protons at a heavy metal where they emit neutrons upon collision, the

neutrons are then directed towards the fuel. This type of reactor would operate subcritical, as a

sustained neutron reaction is not possible without the accelerator.

United States

The United States has been collaborating with China on designs for a thorium-fueled

reactor using a molten salt reactor design. A planned build of a research project reactor near

Odessa Texas using a High Temperature Reactor design with ceramic coated thorium beads, very

similar to the pebble bed design is projected to be operational within the next few years.

In July 2013 Bill Gate’s nuclear power company, TerraPower, announced that it would be

exploring options other than the company’s primary research focus of the traveling wave reactor.

These options included the design of a molten salt reactor with thorium as fuel. TerraPower plans

http://en.wikipedia.org/wiki/Ben-Gurion_University



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on taking parts of designs that proved to be successful at Oak Ridge in the 1960’s but plan to add

more focus on corrosion resistance and would like to take ideas from the traveling wave reactor so

that a thorium powered reactor could operate for many years (up to sixty) without ever requiring

the removal of fuel for reprocessing.



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The Future of ThoriumSO13(a-c)

With a past that has proven thorium is a credible option, many projects around the world

focusing on thorium, which was once thought to be a dead fuel source for nuclear power, the fact

that there is about four times as much thorium available in the world compared to uranium, and

the need to reduce the amount of spent fuel that is being stored, it is clear that we cannot and are

not ignoring the vast possibilities of thorium based reactors.

There are several different types of reactor designs currently in the research and

development stages. The DOE and NRC have identified the following advanced reactor designs

that are non-light water reactors, some of them being capable of using thorium as a fuel; gas-

cooled fast reactor, lead-cooled fast reactor, molten salt reactor, sodium-cooled fast reactor, and

supercritical-water cooled reactor. These are being developed all over the world and some are

even operational outside of the United States. The NRC anticipates that they could receive

licensing applications within the next decade for non-light water reactors. The following are the

most likely to be implemented, utilizing thorium as a fuel, in the next decade based on continued

discussions with the NRC.

GAS-COOLED FAST REACTOR

The main characteristics of the gas-cooled fast reactor are fissile self-sufficient cores with

fast neutron spectrum, robust refractory fuel, high operating temperature, high efficiency

electricity production, energy conversion with a gas turbine and full actinide recycling possibly

associated with an integrated on-site fuel reprocessing facility. A technology demonstration

reactor needed to qualify key technologies could be put into operation by 2020. (nrc.gov)



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LEAD-COOLED FAST REACTOR

The lead-cooled fast reactor system is characterized by a fast-neutron spectrum and a

closed fuel cycle with full actinide recycling, possibly in central or regional fuel cycle facilities. The

coolant could be either lead or lead/bismuth eutectic. The LFR can be operated as a breeder; a

burner of actinides from spent LWR fuel; or a burner/breeder using thorium matrices. The LFR

system may be deployable by 2025. (nrc.gov)

MOLTEN-SALT REACTOR

The molten-salt reactor system embodies the very special feature of a liquid fuel. MSR

concepts, which can be used as efficient burners of transuranic elements (TRU) from spent LWR

fuel, have also a breeding capability in any kind of neutron spectrum ranging from thermal (with a

thorium based fuel cycle) to fast (with the U-Pu fuel cycle). Whether configured for burning or

breeding, MSRs have considerable promise for the minimization of radiotoxic nuclear waste.

(nrc.gov)

The majority of the research and application of test reactors consist of the molten salt

design, as this seems to be the safest way to use thorium and still obtain the benefits of a longer

fuel cycle added by breeding and reduced waste. These advantages are reduced when thorium is

used as a fuel in a traditional pressurized light water reactor. The molten salt reactor design has

been proven and a few countries have used thorium in a PWR, making these two most likely uses

in the near future.

It’s not certain whether or not the future of nuclear power will contain thorium-fueled

reactors. However, it is apparent that there is a strong desire from companies within the United



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States and around the world for designing a new generation of nuclear reactors. The NRC has

adapted their policy for advanced reactor licensing and has spent a countless amount of time

developing policies for licensing of advanced reactors, changes in safety analysis, and analyzing the

shipping, receiving, and storage of nuclear fuel and waste.SO8.b They have prepared themselves for

whatever the nuclear industry brings them as we move forward and they welcome the change.



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CONCLUSION

Thorium was set-aside in 1973 for the use of uranium as a fuel source in nuclear reactors

based on uranium’s ability to produce weapons grade plutonium as a byproduct. This desire to

produce material for nuclear weapons halted what could be one of the greatest advances in

nuclear power, but it is making a comeback in new reactor designs due to its many advantages.

Thorium gives us the opportunity to develop cleaner and safer reactors.

Some of the designs operate subcritical, while others have a built in safety feature that

would automatically dump the fuel into a holding tank in the event of overheating. The

possibility of using thorium in a breeder reactor creates the ability

to significantly reduce or eliminate the long term nuclear waste storage problem that the United

States and the rest of the world is faced with and would require less frequent shutdowns for

refueling.

Approximately twenty five percent of the energy produced in this country is from nuclear

power. Uranium has been capable of meeting this demand but not without its drawbacks.

Thorium gives us the ability to address these drawbacks as we expand the quantity of nuclear

power generation, propelling the nuclear industry moving forward into the twenty first century.



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ACKNOWLEDGMENTS

From Austin Corazzin: I would like to thank my wife for always being supportive of me during my

entire college experience, Dr. Devore for facilitating this class in a very professional manner and

helping me along the way by answering all my questions and making me strive to do my best, and

my team mates Adam and Ben, this paper would have never happened without all the hard work

and long hours you have dedicated along the way.

From Adam Wood: I would also like to thank my wife for supporting me throughout my time

working and attending school. I would like to thank Austin and Ben as well for their help

throughout this project. Last I would like to thank that faculty that has worked with me through

my classes at TESC.

From Benjamin Smith: I would like to thank the US Navy for allowing me the opportunity to

develop my expertise in nuclear power and to continuing to fund me throughout my endeavor to

earn a degree. I would also like to thank Thomas Edison State College faculty and staff for assisting

me in my quest for knowledge and allowing me to receive credit for my experience and knowledge

gained in the Navy. I would also like to thank my wife for her support and understanding as I

pursued my degree while working full time.



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from http://www.itheo.org/articles/how-many-thorium-mms-do-you-consume

Waltar, A.E.; Reynolds, A.B (1981). Fast breeder reactors. New York: Pergamon Press. p. 853.

www.thoriumpowercanada.com/technology/the-projects/.

1953-1987. Peakhurst, N.S.W.: Glen Haven.

http://www.itheo.org/articles/how-many-thorium-mms-do-you-consume



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APPENDIX

Student Outcome # 1 - Demonstrate a fundamental mastery of the knowledge, techniques, skills and

modern tools required for nuclear facility operations and/or related fields.

a. Demonstrate mastery of knowledge of nuclear operations. Describe nuclear process as it relates to

field of study.

b. Demonstrate mastery of knowledge of techniques and skills utilized during nuclear operations.

Relate the techniques and skills required in the field of study.

c. Demonstrate mastery of knowledge of modern tools utilized during nuclear operations/related field

of study. Identify the modern tools employed in the field of study

(computers, instruments, etc.)

Student Outcome # 2 - Demonstrate an ability to understand and apply current concepts in the areas

of mathematics, science, engineering, and technology to engineering technology/nuclear facility

problems using proper application of principles and applied procedures or methodologies.

Student Outcome # 3 - Demonstrate the ability to conduct standard tests and measurements in the lab

or in the field; similarly, to conduct, analyze, and interpret experiments; and apply results to resolve

technical challenges and improve processes.

a. Demonstrate ability to conduct field/lab measurements and tests. Provide examples of field/lab

experiments, tests, etc. performed in the field of study and conclusions reached.

b. Demonstrate ability to analyze and interpret experimental results. Show examples of field/lab results

and analysis/interpretation and conclusions reached.



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c. Demonstrate ability to apply results to resolve technical challenges. Describe how field/lab results

were applied to the resolution of issues.

Student Outcome # 4 - Demonstrate the ability to design or redesign systems, components or

processes that are used for efficient and safe operation of a nuclear facility.

a. Demonstrate the ability to recognize the need for design /redesign requirements. Describe a

requirement for a design / redesign in the field of study.

b. Demonstrate the ability to properly choose design applications for improvements to safe/efficient

operations. Describe a design / redesign effort including: system, component, material selection,

process or procedure, key considerations.

Student Outcome # 5 - Demonstrate effective leadership and participation as a member of a technical

team.

a. Demonstrate leadership attributes: command & control, organization, resource management, lead

by example.

b. Demonstrate effective team participation on technical teams. Roles & responsibilities: individual

accountability, cooperation, and participation.

Student Outcome # 6 - Demonstrate a capability to solve technical problems through proper

identification, research, and systematic analysis of the issue.

a. Demonstrate use of problem solving techniques through proper identification, analysis and

corrective action taken. Describe the processes and principles used in correct problem identification.

Describe root cause methodology utilized. Describe the successful corrective action taken.



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Student Outcome # 7 - Demonstrate proficiency in oral, written, and graphical communications in a

technical and non-technical setting utilizing standard English.

a. Organization, structure, and presentation of oral communication facilitates ease of understanding for

the intended audience.

b. Organization, structure, and presentation of written communication facilitates ease of understanding

for the intended audience.

c. Content and knowledge of oral communication illustrates technical understanding of the material.

d. Content and knowledge of written communication illustrates technical understanding of the

material.

e. Demonstrate proficiency in use of graphical communication, both technical and non-technical, such

as: visual aids, power points, tables, graphs, or figures.

f. Spelling and grammar used in written documentation is high quality. Standard English language is

used throughout.

g. Reference to research citations and document format are in accordance with approved TESC

guidelines.

Student Outcome # 8 - Demonstrate an ability to identify and use appropriate technical literature,

documents and procedures.

a. Demonstrate ability to use appropriate technical literature and documents. Provide examples of

technical literature/documents utilized in field of study and describe their value.

b. Demonstrate ability to use appropriate procedures. Describe the hierarchy of procedures. Describe



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the methodology and value behind procedure usage. Describe the administrative processes for

procedures in the field of study.

c. Research citations in oral and written communication are derived from reliable sources such as

technical documents and professional journals.

Student Outcome # 9 - Demonstrate the need for and commitment to engage in self-directed

continuing professional development and life-long learning in one’s discipline.

Student Outcome # 10 - Demonstrate professional, ethical, and social responsibilities within the

nuclear energy field, while recognizing differences due to culture and diversity.

a. Demonstrate professional behavior. Provide examples of experiences in the field of study.

b. Demonstrate ethical behavior. Provide examples in the field of study.

c. Demonstrate social consciousness. Provide examples of social consciousness in field of study.

d. Demonstrate recognition of culture and diversity differences. Provide examples of

incidents/behavior/recognition of culture and diversity.

Student Outcome # 11 - Demonstrate recognition of the impacts of nuclear technology solutions in an

expanding societal and global context.

a. Demonstrate knowledge and awareness of global nuclear industry problems/incidents and

application of technical solutions. Describe recent problems or incidents in the field of study and the

application of solutions/improvements as a result. Describe implementation of lessons learned.

Student Outcome # 12 - Demonstrate a commitment to quality, timeliness, and continuous

improvement in professional activities.



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a. Demonstrate a commitment to quality. Illustrates examples of behaviors or activities. Provide an

example of quality improvement suggestion.

b. Demonstrate a commitment to timeliness. Illustrates examples of behaviors or activities.

c. Demonstrate a commitment to continuous improvement. Illustrates examples of behaviors or

activities. Provide an example of continuous improvement suggestion.

Student Outcome # 13 - Demonstrate knowledge and understanding of the Federal, State, and Local

regulations, standards, and rules applying to operations and safety in the nuclear energy field.

a. Demonstrate knowledge of nuclear Federal regulations, rules and standards as it applies to safe

operations of a nuclear facility. Describe the Federal regulations applicable to the field of study.

b. Demonstrate knowledge of State regulations, rules and standards as it applies to safe operations of a

nuclear facility. Describe the State regulations applicable to the field of study.

c. Demonstrate knowledge of Local Regulations, rules and standards as it applies to safe operations of a

nuclear facility. Describe the Local regulations applicable to the field of study.

All of the above Student Outcomes are denoted throughout the paper by the use of superscripts

(SO) with the following exceptions:

Student Outcome #5 has been met throughout the course by the constant communication and

work within the team to complete the problem statement, outline, and final paper.

Student Outcome #6 was applied to problem solving of choosing a topic and researching the topic

and the potential solutions for use of thorium reactors.



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Student Outcome #7.a and 7.c were demonstrated during each team member’s individual oral

presentation.

Student Outcome #7.b, 7.d, and 7.f were demonstrated throughout the writing of the problem

statement, outline, and final paper.

Student Outcome #8.a and 8.c were demonstrated by the proper use and documentation of all

applicable references used throughout the research paper and the oral presentation, and their

proper formatting and citation.

Student Outcome #9 and 12.c have been demonstrated by all participants taking college courses to

pursue a degree in their related field of study and by participation in continuing training programs

in the Navy’s Nuclear Propulsion Program.

Student Outcome #10.a and 10.b have been demonstrated by a continued commitment to honesty,

integrity, and reliability in the day to day operations, training, and maintenance of a Naval Nuclear

Propulsion plant.

Student Outcome #11 has been demonstrated throughout the paper by focusing on the future of

nuclear power and the use of thorium as a cleaner and safer fuel source for the future.

Student Outcome #12.a has been demonstrated by the quality of work put forth throughout the

NUC-495 course.

Student Outcome #12.b has been demonstrated by the timely completion of assignments

throughout the course.

thorium final project final rev

Documents