Last month, Canada's use of highly-enriched uranium (HEU) to create medica
l isotopes for medical diagnoses caused controversy at the nuclear security summit in Korea. The United States, Belgium, France, South Africa, and the Netherlands have all agreed to phase out the use of HEU.
A matter of concentration
The nuclear fuel cycle begins with mining uranium and milling the ore. These recovery operations produce yellowcake, which is transported to a fuel cycle facility where it is transformed into fuel for nuclear power reactors. In addition to yellowcake, uranium recovery operations generate waste products called by-product materials. Enriched uranium is important for nuclear power reactors and for military nuclear weapons.
Reactor types and applications
HEU has a
20 percent concentration of uranium and is used in
, which require about 20 percent or more fissile material for their cores. It is also used in the production of medical isotopes, and in
, where at least 50 percent concentration is required.
The majority of HEU
is limited to eight research reactors, most of which are in Europe, and all but one of which are at least four decades old. As much as 95 percent of the global supply of HEU has historically been produced in Canada, Belgium, France, South Africa, and the Netherlands.
International Atomic Energy Agency
attempts to monitor enriched uranium in order to advocate civil nuclear power generation and limit nuclear weapons proliferation. The primary objectives of the
are to reduce the spread of weapons technology and enhance cooperation in civilian use to achieve nuclear disarmament.
Fissile uranium in nuclear weapons usually contains a concentration of uranium that is 85 percent or higher, and is classified as “weapon(s)-grade.” However, for an unsophisticated or inefficient weapon, a concentration of 20 percent uranium is considered “
,” and in theory even lower enrichment may be sufficient.
Medical imaging technology uses medical isotopes in the treatment and diagnosis of many conditions, from cancer to neurological diseases. The scope of this multibillion dollar business is anticipated to
as much as four percent annually for at least a decade.
Timothy Meyer, Head of
Strategic Planning & Communications with
, Canada's national laboratory for nuclear science, explained the implications for medical science in an exclusive interview with Uranium Investing News. “From our perspective, the increasing global pressure to move away from any and all supply chains that employ HEU is driving innovation and the development of alternative technologies. For instance, the government of Canada provided $35 million to four Canadian teams in 2012 for a two-year effort to develop methods for producing technetium-99m - the highest-demand medical isotope produced by the NRU [National Research Universal] reactor in Chalk River, Ontario - without employing nuclear reactors or uranium.” Technetium-99m is used in 85 percent of all nuclear medicine procedures, estimated globally at 20 million per year.
Low-enriched uranium (LEU) has a concentration of uranium that is below 20 percent, and is used in commercial
light water reactors
. Currently these tend to be the more prominent nuclear builds, and require a uranium fuel supply that is enriched from between three to five percent.
Meyer explained that implications for the mining industry will be limited, commenting, “the utilization of HEU material as 'targets' for irradiation in the NRU research reactor is not a large demand on the overall uranium extraction industry. The NRU reactor is unlikely to continue producing medical isotopes using HEU until about 2016, when the current operating license for those activities expires. The HEU used by Canada's NRU for medical isotope production in the NRU is sourced from the United States.”