Part 1 of A Historic Review of the Canadian Nuclear Industry: The Early Years

The below is part one of a five-part series detailing the history of Canada’s nuclear industry written by Michael Alexander Sinclair. It was originally submitted as an essay on November 15, 2017 for Ryerson University’s HST 701: Scientific Technology & Modern Society, and has since been modified for publication onto the Mackenzie Institute website.

When uranium was first discovered in 1789 by a German chemist named Martin Klaproth, he named it after the planet Uranus, so named for the primal Greek god that originally ruled the universe.[1] Historically, advancements in nuclear research have occurred at very rapid rates. Starting in earnest in 1895 with the original discovery of ionizing radiation, German scientists Otto Hahn and Fritz Strassmann had already demonstrated by 1939 that nuclear fission did not only produce energy but also additional neutrons that could cause other nearby uranium atoms to fission.^[2]  The potential applications for this exciting new discovery were boundless, and Canada was quick to respond to the emerging field of nuclear applications. Canadian scientists were involved in nuclear research at the beginning, and in the 1930s the country was at the forefront of nuclear science, technology and expertise. Today, there is no question that Canada is still not only a major participant but also a leader within the international nuclear community. Deeply engrained in both the country’s history and its modern society, it is difficult to imagine Canada as a country without its nuclear industry, and by extension its nuclear reactors.

The scientific research that Canada has performed in its quest to develop nuclear applications has furthered scientific knowledge and advanced the global understanding of the benefits of nuclear power. As a global leader in nuclear research, Canada’s achievements have ensured its place among the nuclear nations. The technology and innovation born from Canadian research are the fundamental reasons behind its success. The Canadian nuclear industry has produced elemental isotopes for medical purposes that Canada has used domestically as well as supplied to the rest of the world.  The technologies and scientific fields built around these isotopes have had an enormous impact globally . As a direct result of Canada’s research and development in medical applications of nuclear radioisotopes, today over 40 million nuclear medicine procedures are conducted annually in over 10 thousand hospitals globally. One specific isotope produced by Canadian reactors, Cobalt-60, is used in over 10 million cancer treatment procedures annually, and since the inception of this medical advancement Canada has been the major global supplier of this life-saving isotope.[3]

Canada has also produced the CANDU reactor, standing for CANada Deuterium Uranium, which cemented the country’s place as a global player in nuclear power production expertise. It is designed to use natural uranium as fuel, possible through the use of deuterium, called heavy water, as a neutron moderator. This type of reactor has many advantages over conventional light water reactor designs that use enriched uranium fuels cooled and moderated by pressurized light water. These include the ability to be refueled online, lower cost fuel, the potential to use alternate fuels, and design aspects that make these reactors exceptionally safe. CANDU reactors feature simple designs and manufacturing. These characteristics provide developing nations the ability to utilize inexpensive nuclear power rather than restricting technology to only the first-world nations that have access to more complicated and heavier industrial manufacturing processes. Currently, there are 31 CANDU reactors in the world, spread globally amongst seven countries, with 19 reactors deployed across Canada and 12 reactors exported to South Korea, Romania, Pakistan, India, China and Argentina Additionally, there are 13 reactor designs based on the CANDU design.

In order to provide context, this paper will examine events that occurred at the very beginning of the nuclear industry within Canada, where one of the most important and fundamental contributions to nuclear physics occurred. Around the start of the 20^th century Ernest Rutherford,  a New Zealand born physicist who was called “a second Newton” by none other than Albert Einstein, was hired by McGill University. After becoming the first research student t o study at the University of Cambridge’s Cavendish Laboratory in London, England, Rutherford made the move to Canada where his scientific discoveries would completely change our understanding of matter[5] Rutherford, often called “the father of nuclear physics” established what came to be known as the Montreal Laboratory at McGill in Quebec, Canada. With the assistance of Frederick Soddy, Rutherford was awarded the Nobel Prize for Chemistry in 1908 for his work conducted in Canada.  The paper he and Soddy authored ushered in a new age of nuclear physics and established the base upon which the future of nuclear development was to be built. As nuclear theory developed further on a global scale over the course of the next four decades, a new goal to harness the phenomena of atomic disintegration and the energies it can produce appeared: how to physically create a nuclear chain reaction using fissile uranium atoms.

In 1940, the first attempt to achieve a self-sustained critical nuclear reaction in Canada was by George C. Laurence  under the Canadian National Research Council (NRC). Laurence was a Canadian nuclear physicist who received his doctorate degree under Rutherford, at the Cavendish Laboratory from Cambridge University. Laurence returned to Canada to join the NRC in 1930 where he established a laboratory that focused on the study of radiation in cancer treatment[11] [12] [13]

Laurence’s goal in 1940 was to create a self-sustaining nuclear reaction. It was already known at this point that nuclear fission could be achieved when a uranium atom was struck by a neutron. It was also known  at this time by scientists around the world that moderating neutrons improved the chance of fission. However, key challenges during the early days of nuclear science was in producing large scale quantities of sustainable energy under controlled conditions.

Bulk fission would only be possible if the uranium fuel could capture at least as many neutrons as the reaction itself was producing. There had been previous experiments involving uranyl nitrate dissolved in normal water that had failed. It appeared more promising when using heavy water, formally called deuterium, which are water molecules composed of hydrogen atoms that contain two neutrons instead of just one neutron. Heavy water, however, was both rare and expensive to produce. The British possessed the majority of the world’s supply at this time. Thus, Laurence chose to use carbon instead as a moderator for the first Canadian nuclear reactor and uranium oxide as the fuel. The experimental reactor was humble in design; Paper bags of uranium oxide were dispersed amongst paper bags of carbon, contained within a gigantic paraffin wax-lined wooden bucket. Although the rate of neutron capture and release by fission was measurable, it was found that the capture rate was a few percentages lower than the production rate; the reactor was unable to achieve criticality.[14]

Stay tuned for part two of five coming soon.