Segment one introduces the element uranium and some of its basic properties. Although uranium occurs naturally in low concentrations in soil and water, it is commercially mined in Canada, Australia, Kazakhstan, Namibia, Niger, and Russia- countries in which uranium is present in higher concentrations.
Segment two discusses the important research of German chemist Martin Heinrich Klaproth and French physicist Antoine Henri Becquerel that led to the discovery of uranium’s radioactive properties.
Segment five and segment six explore what alpha, beta, gamma, and neutron radiation is and why radioactive elements such as uranium can be very dangerous to work with and can have potentially disastrous effects to humans and the environment when a radiological incident occurs.
Segment eight examines how uranium deposits are located and subsequently mined using techniques such as open-pit, underground, and the most common method, in-situ recovery mining. Research is now being conducted into extracting uranium from seawater, where it exists naturally in low concentrations.
Segment nine focuses on uranium milling, the process in which raw uranium is chemically separated from any other elements that may have been extracted with it and processed into a usable powder known as “yellowcake.”
Segment ten discusses uranium conversion, a process in which uranium is purified even further and then converted into uranium hexafluoride where it is stored in cylinders and shipped to an enrichment facility.
Segment eleven discusses uranium enrichment, a process in which uranium isotopes are separated for the purpose of collecting higher concentrations of uranium-235. A sample of uranium containing 3-5% uranium-235 is considered energy-grade and is called low-enriched uranium. The same processes, most commonly completed using gas centrifugation, can be used to enrich a sample of uranium to about 90% uranium-235 and can be used to produce nuclear weapons, a concern that factors into the current international conflict with Iran over its uranium enrichment program.
Segment twelve discusses spent fuel reprocessing, a process in which plutonium and uranium is separated from the byproduct of nuclear energy generation. This process is highly controversial due to separated plutonium being a weapons-ready material and thus must be strictly controlled.
Segment thirteen and segment fourteen discuss what nuclear waste is and provides an overview of the complicated issue of how to handle nuclear waste. Because nuclear waste is a long-term radiological threat, much more permanent waste repositories are needed than the existing facilities that are currently only able to store nuclear waste temporarily. The construction of permanent repositories have been highly controversial due to their potential environmental and social effects- valid concerns which will be necessary to address in the future for the continued safety to humans and the environment from radioactive nuclear waste.
The Nuclear Fuel Cycle:
This graphic makes it easy to visualize how each of these processes discussed throughout the Nuclear 101 series fit together to create the nuclear fuel cycle. From uranium mining and milling to conversion into material that can go through the enrichment process, this material is then used by nuclear reactors to produce energy. That byproduct can either go directly to storage or can be reprocessed. If reprocessing occurs, some of that material will again be used for energy generation resulting again at the stage of waste storage until a final disposal method, such as a deep underground waste repository, is established. Safety along all aspects of the nuclear fuel cycle is crucially important for the continued use of nuclear energy. The unanswered questions of what to do with nuclear waste is probably one of the most important issues to tackle in the near future. Simply put, it is irresponsible to continue accumulating an ever-growing stockpile of radioactive waste without an environmentally safe long-term disposal solution.
An important factor often removed from many fuel cycle graphics is the point in which nuclear proliferation is possible. As shown by this graphic, there are multiple paths to nuclear proliferation. Highly enriched uranium can be used to develop a weapon and so can the process of separating plutonium from nuclear waste. Enrichment and reprocessing are both highly regulated practices. Despite this international oversight, both of these processes are controversial and have led to international disputes, several of which have been highlighted throughout the Nuclear 101 blog series.
Because many of the current international conflicts involving nuclear issues involve the use of nuclear technology itself, it is vitally important to have accessible information to create a foundation of knowledge which can be used when discussing these complex topics. We hope that you have enjoyed this series and were able to learn from it and feel more confident in your understanding of nuclear technology and some of the controversies that surrounds it. We encourage you to join in the discussion. Issues surrounding nuclear energy and nuclear weapons affect us all, and therefore, we all should have a voice in the discussion- even if we are not all nuclear physicists!
If you are interested in learning more about the technical aspects of nuclear energy or nuclear weapons here are some resources to start with:
IAEA: Nuclear Fuel Cycle Information System
US Energy Information Administration: Nuclear Explained
Up-to-date IAEA discussions and publications regarding the nuclear fuel cycle waste technology
Thanks so much for reading! It has certainly been fun writing this blog series. I hope that I have reached my objective of making the technical aspects of nuclear issues more approachable to those who wish to get more involved in dialogue surrounding nuclear disarmament and nonproliferation issues. If you would like to contact me please email me at firstname.lastname@example.org.
I would like to thank everyone at the Project for Nuclear Awareness and our supporters for the memories! My fellowship has been both challenging and informative. If you are interested, I have written a short testimonial about my fellowship which you can read here. Thank you for your continued support of PNA.