NRU Reactor

NRC's Canadian Neutron Beam Centre is based at Canada's largest and most productive science facility: the NRU reactor at Chalk River Laboratories. The materials research program involves a wide network of Canadian and international scientists, and impacts many fields of science and technology including the aerospace, health, automotive, chemical, manufacturing, electrical and computing sectors.

Alongside the world-class materials research facilities of NRC, the NRU reactor produces medical isotopes used in 16 million cancer treatments, and 5 million medical image scans a year. It is also the prime R&D tool used by Atomic Energy of Canada Ltd. in developing fuels and materials for Canada's nuclear electrical generating stations.

You can read more about the history and achievements of the NRU reactor at www.NRUreactor.ca.

The NRU reactor at Chalk River Laboratories has operated since 1957, and has been the birthplace of many scientific achievements. Canadian physicist Bert Brockhouse won the Nobel Prize in Physics for his seminal work at NRU using neutron scattering to explore materials.Using the same scientific approach that Brockhouse pioneered, NRC scientists today apply neutron scattering techniques in a wide range of research into materials.

In addition to five decades of neutron scattering research, NRU is the source of the majority of the world's supply of medical isotopes. These materials are used in the diagnosis and treatment of cancer and other diseases. Isotopes from NRU benefit more than 5 million people internationally each year: a huge contribution to world health.

Moreover, NRU is the source of the fundamental knowledge that was required to develop Canada's fleet of nuclear power stations. Fuel and structural material needed to build a CANDU reactor are tested and proved in NRU. Domestic nuclear power generation prevents millions of tonnes of greenhouse gas emissions each year, by reducing Canada's use of fossil fuels, and is a $5 billion industry.

Key Features

The NRU reactor at AECL's Chalk River Laboratories has provided intense beams of neutrons since it began operation in 1957. The reactor uses heavy water as both moderator and coolant and operates at 125 MW. Presently it uses 20% enriched fuel. It has a large core contained in a vessel that is 12 ft. in diameter and 10 ft. high. The core contains ninety fuel sites and has eight reactor loops and thirty isotope irradiation sites. It has seven beam tubes dedicated for neutron scattering instruments. The on-line fueling capability of NRU means the reactor does not operate on a fixed fueling cycle. Rather, shut-downs are scheduled by the scientific, engineering or maintenance needs.

The peak thermal flux in NRU, 3×10¹⁴ cm^-2 sec^-1, remains one of the highest in the world. The beam tubes are large, 22 cm high by 7.5 cm wide, to give beam optics that produce a high flux on the specimen. The floor plan of the reactor experimental hall is shown schematically on another page, with the neutron scattering spectrometers outlined and identified by the beam hole designations.

The Future

The NRU reactor has operated reliably since 1957. The current intent is to further refurbish it to enable operation to around 2012. A replacement facility would take approximately six years to construct. It is prudent therefore for a decision to be made now about the future of these three important areas of science and technology that rely on a neutron source as the centre of their activities.

The Canadian Neutron Facility (CNF) is a major science investment, that impacts energy, health, research, industry and education. As a project, its scale is beyond the scope of any single department or agency. The CNF is a strategic element of the national science infrastructure, that requires appropriate funding and governance to maximize its benefit to Canada.