AECL-6959

ATOMIC ENERGY (P2i^ LENERGIE ATOMIQUE OF LIMITED Vj&JT DU CANADA LIMiTEE

SOME HIGHLIGHTS OF RESEARCH AND DEVELOPMENT AT AECL

Fait saillants des recherches et developpements a L'EACL

W.J. LANGFORD and H.K. RAE

A lecture presented to the Chinese Nuclear Energy Society, Peking. May 1980

Chalk River Nuclear Laboratories Laboratoires nucleaires de Chalk River

Chalk River,

June 1980 juin ATOMIC ENERGY OF CANADA LIMITED

SOME HIGHLIGHTS OF RESEARCH AND DEVELOPMENT AT AECL

by

W.J. Langford and H.K. Rae

A lecture presented to the Chinese Nuclear Energy Society Peking - May 1980

Research Company Chalk River Nuclear Laboratories Chalk River, Ontario, KOJ 1JO 1980 June AECL-6959 L'ENERGIE ATOMIQUE DU CANADA,

Fait saillants des recherches et développements à L'EACL

par

W.J. Langford et H.K. Rae

Résume

L'objectif des programmes de recherche et développement de 1'EACL est de renforcer les connaissances et les aptitudes nécessaires pour atteindre les objectifs nationaux dans le domaine de l'énergie nucléaire. Ces objectifs comprennent une filière nucléaire répondant à la capacité industrielle du Canada. Cette filliêre, qui est réalisée, va maintenant être élaborée par des développements scientifiques et technologiques pour répondre aux besoins du pays dans un avenir prévisible. Les programmes de R&D de l'EACL sont minutieusement intégrés et orientés pour tirer le meilleur parti possible du financement disponible. Les installations à'j recherche mises au service de ces programmes comptent parmi les meilleures au monde. Elles permettent de faire toute une gamma d'études allant de la physique nucléaire fondamentale à l'irradiation et à l'essai de composants grandeur nature de réacteurs de puissance. Dans ce rapport, on a pu seulement mettre en exerque quelques aspects importants des programmes dans les principaux domaines d'activités.

Société de recherche Laboratoires nucléaires de Chalk River Chalk River, Ontario KOJ 1J0 Juin 1980

AECL-6959 ATOMIC ENERGY OF CANADA LIMITED

SOME HIGHLIGHTS OF RESEARCH AND DEVELOPMENT AT AECL by W.J. Langford and H.K. Rae

ABSTRACT

The research and development programs of AECL have as their goal the strengthening of the knowledge and ability necessary to achieve national objectives in the field of nuclear energy. These objectives include a system appropriate to Canada's industrial capabilities, now realized, and the extension of that system, through scientific and technological development, to serve the nation's needs for the foreseeable future. The Company's programs are carefully integrated and focused to use the available funding to maximum advantage. The research facilities on which the program depends are among the best in the world, and support a full spectrum of research from fundamental nuclear physics to full-scale power reactor component irradiation and testing. In this report it has only been possible to high-light some important facets of the programs in each of the principal areas currently employing our energies.

Research Company Chalk River Nuclear Laboratories Chalk River, Ontario, KOJ 1J0 1980 June

AECL-6959 TABLE OF CONTENTS

SECTION PAGE

1. Program Scope 1 2. Program Evolution 4 3. Program Highlights 8 3.1 Organization 8 3.2 Underlying Research and Advanced Systems 9 3.3 Power Reactor Systems 11 3.4 Processes 16 3.5 Environmental Protection and Waste Management 17 3.6 Advanced Fuel Cycle 20 3.7 Technology Transfer 22 3.8 International Collaboration 22 4. Summary 24 REFERENCES 28 SOME HIGHLIGHTS OF RESEARCH AND DEVELOPMENT AT AECL

Most Canadian research and development in atomic energy is conducted by the Research Company of the federally owned Crown Corporation, Atomic Energy of Canada Limited(l). AECL's research and development program provides a coherent technological base underlying the whole Canadian nuclear industry with the exception of mining and refining. Research and development related to mining is conducted by the Geological Survey of Canada and other sections within the federal Department of Energy, Mines and Resources, as well as by the uranium producers themselves. Research and development related to uranium refining is mainly done by Eldorado Nuclear, another federal Crown Corporation(2). We will divide this description of AECL's research and development activities into three parts: . A general description of the breadth and scope of our program today; . An outline of the evolution of research and development at AECL in support of the Canadian program; . A series of brief highlights illustrating recent accomplishments in both basic nuclear science and reactor development. — 2 —

1. PROGRAM SCOPE The basic mission of AECL is to produce the greatest benefit for Canada from the peaceful uses of atomic energy and related technologies. The mandate of the Research Company is to conduct both the basic and applied research and development in support of this mission. In fulfilling this mandate, the Research Company acts as Canada's national laboratory for atomic energy, it develops nuclear technology for the power reactor program, and it transfers this technology to Canadian industry so it can be put to use.

The program spans the whole spectrum from basic nuclear science to large-scale engineering development. On the one hand, AECL scientists are working at the forefront of nuclear physics and radiation biology as they study the detailed structure of the atomic nucleus or the interaction of radiation with DNA within the human cell. On the other hand, AECL engineers are among the world leaders in measuring heat transfer within full-scale reactor fuel channels or in providing the data and techniques to predict the performance of large nuclear steam generators. There are many other groups who contribute to nuclear research and development in Canada. The two largest provincial utilities, and Hydro , have important nuclear programs within their research departments. Ontario Hydro, with its large nuclear generation capacity (14 GWe in-service and under construction), focuses its supporting experimental work primarily on short to medium term projects associated with reactor operation(3). Hydro Quebec, with only a modest nuclear program so far, has tended to choose longer range research projects in atomic energy including some preliminary work on fusion(4). Several industrial companies, for example Westinghouse Canada Limited and Canadian General Electric who both fabricate , have small research groups. Some provincial government research organizations, such as the Research and Productivity Council, have begun nuclear development work. Many Canadian universities are also engaged in nuclear research.

However, none of these other groups approaches anything like the full scope and breadth of the AECL Research Company. This is one of our greatest strengths, and enables us to conduct a wide range of complex development projects successfully by using large multidisciplinary teams of scientists and engineers. This combination within the Research Company of broad basic science programs and large mission oriented development projects is unique in Canada. - 3 -

As such, it is an invaluable part of the total scientific and technical resources of the country. The total technical effort of the Research Company is small by international standards, yet Canada has been able to develop a highly successful nuclear power system and a nuclear industry. This has come about by concentrating our resources on a single reactor type, and by backing the development with a strong fundamental scientific base. Although the focus of our reactor development program has been narrow, we have used our basic science program to maintain a broad awareness. We have always recognized that it is equally important to understand what we are not doing and why, as it is to understand what we are doing.

Maintaining the highest possible standards of excellence for our basic research enables AECL scientists to establish strong links with other institutions throughout the world. Thus, they can be conversant with advances in nuclear energy fields outside our own program. AECL can thereby assess progress and prospects to determine if and when it appears Canada should enter such fields - our on-going assessment of fusion technology is a case in point(5). This breadth and depth of expertise also puts the Research Company in a good position to act as consultant and advisor to the federal government on national strategies for nuclear- related activities. Atomic Energy of Canada Limited consists of a Corporate Office and -five Company Divisions - Research Company, Chemical Company, Radiochemical Company, Engineering Company, and AECL-International - See Figure 1. The Research Company is the technological base for many of the activities of the other Companies within AECL, as well as for the Canadian nuclear industry as a whole. A large part of the effort of the Research Company is devoted to the needs of designers and builders of nuclear power stations (Engineering Company); producers of medical and industrial irradiation facilities (Radiochemical Company); and operators of heavy water plants (Chemical Company).

The Research Company is divided amongst three sites - a Head Office in , laboratory facilities and two large, high- flux research reactors at the Chalk River Nuclear Laboratories (CRNL) (Figure 2), and laboratory facilities and a third high-flux at the Whiteshell Nuclear Research Establishment (WNRE) (Figure 3). The locations of these sites are shown in Figure 4. - 4 -

Today, the Research Company employs about 3100 scientists, engineers, technologists and support staff at its three sites (Figure 5). The Research Company budget for 1979/80 was approximately C$140 million, of which C$130 million was for operating expenditures and C$10 million for capital. About 8 5% of this funding is by vote from the , while most of the remainder comes from the commercial sale of research and development and other services by the Company, normally under contract to organizations seeking to take advantage of the unique facilities at our laboratories. The commercial component of Company funding is expanding, and is expected to account for more than 25% of the total funding within ten years. Of the total professional staff of 690 shown in Figure 5, about 400 scientists and engineers are directly engaged in research and development. The remainder form a part of the total supporting staff of 2700. This ratio of nearly 7 to 1 for support staff to researcher is high compared with many other institutions. However, it is readily understood from the following requirements: operation of large test reactors; design, construction and maintenance of complex engineering test facilities; remote locations requiring considerable self-sufficiency; handling large amounts of radioactive material. We have already mentioned the small size of Canada's nuclear research and development in the international context. This is illustrated in Figure 6 where the annual expenditure on civil nuclear programs in current US dollars is shown from 1955 to 1979 for Canada, Japan, United Kingdom, France, West Germany and United States. The Canadian expenditure is half that in the UK, a third that in France and a tenth that in the US. - 5 -

2. PROGRAM EVOLUTION Some historical oackground will help set the present programs of the company in perspective. The first reactor in the world outside the United States began operation at CRNL in September 1945. This was ZEEP, a zero energy fuelled, heavy water reactor for physics measurements to assist in design of the high flux heavy witer reactor then being built at CRNL.

In 1947 this much larger reactor, NRX, started up. For several years it was the most powerful research reactor in the world (Figures 7, 8 and 9). Today, in its 33rd year of operation, it remains an important research tool(6). The aluminum vessel containing the reactor core has been replaced twice(7) and this need has provided valuable experience in the rehabilitation of nuclear facilities. The Chalk River Project operated under the auspices of the National Research Council of Canada until 1952, when AECL was formed to focus the program on the feasibility of a nuclear power reactor to produce electricity. Irradiation facilities to test fuel at power reactor conditions and for material testing began to be installed in NRX(8). At the same time, Canada pioneered commercial production of radioisotopes, particularly the production and use of cobalt-60 in cancer therapy units(9). In 1957 a more powerful research reactor, NRU, was commissioned to extend Canadian facilities for production and research (Figure 10)(10,11). A unique and important feature of NRU was the ability to change fuel with the reactor at full power. Experience with this fuelling machine, shown in Figure 11, pioneered the concept of on-power refuelling which is one of the cornerstones of the Canadian power reactor system. Today NRU is still a unique irradiation facility in the world. It offers a high flux over a large core volume, accommodating four large fuel irradiation faci.l'ities(8) , and providing many powerful neutron beams for physics experiments(12).

By the time NRU became operational, AECL, in conjunction with Ontario Hydro and Canadian General Electric, was already looking confidently at the prospects for the economic utilization of fission energy from the natural uranium, heavy water moderated reactor to produce electricity. A joint AECL-utility industry group conceived a demonstration reactor of 20 MWe which was named Nuclear Power Demonstrator (Figure 12)(13). This reactor started up in 1962 and has produced - 6 -

electricity reliably ever since. It is the prototype of the successful CANada Deuterium Uranium (CANDU) reactor system(14). Although NPD was conceived as a pressure vessel reactor, the rapid developments in zirconium alloy technology, coupled with fresh analysis of the economics for a commercial reactor of 200 MWe size, led to its redesign as a horizontal pressure tube reactor, which could be refuelled on power. In addition, the large size of pressure vessel necessary for a heavy water reactor would have made further scale-up beyond 200 MWe uncertain, and well beyond any likely domestic fabrication capability.

This now familiar horizontal pressure tube reactor design has separate heavy water circuits for moderator and heat transport systems (Figure 13). The pressurized heavy water (PHW) heat transport system must accommodate on-power refuelling of every channel, contains pumps and valves, and has a large surface area of thin-walled tubing in the steam generator. One of the most crucial demonstrations successfully achieved by NPD was low heavy water leakage from this complex system, and reliable performance of all its components. NPD was the beginning of the CANDU series. Work proceeded rapidly to a full-size demonstration, the Douglas Point Reactor - commissioned in 1966. Next came the first fully commercial power station at Pickering, Unit 1 of which was commissioned in 1971. In parallel with Pickering, KANUPP was built in Pakistan and began operation in 1971, while the first RAPP reactor was completed in India and started up in 1972. Then came the 3000 MWe Bruce Generating Station with the first two units coming on-line in 1977. The complete CANDU nuclear program is illustrated in Figure 14(15); today 13 reactors are operating and construction is in progress on 16 more to give a total committed capacity of 17 GWe in six countries. The relationship of the various research reactors to the power reactor program is illustrated in Figure 15.

Comparing the Bruce station to NPD, the increase in power output is more than a factor of one hundred in 15 years. During this time fuel development has permitted a five-fold increase in power output from a single fuel bundle. Thus, most of the increase in station power in going from NPD to Bruce was obtained simply by using many more and longer fuel channels.

While most of the development effort in the 1960s and early 1970s went into the CANDU-PHW system, other reactor types based on natural uranium fuel and heavy water moderator were also explored. One, using an organic liquid as heat - 7 -

transport fluid (CANDU-OCR), was commissioned at WNRE in 1965, and has operated very successfully(16,17) with reactor outlet temperatures as high as 670 K - 100 K higher than for PHW. WNRE was established in 1962 with the organic cooled reactor development as the main focus of its program. A second reactor type, using boiling light water as the heat transport fluid and with a vertical array of pressure tubes, called CANDU-BLW, was built at Gentilly in Quebec(18); it began operation in 1972. Figure 16 compares the three CANDU types(19). At the time of their conception and introduction into the program, each of these alternative CANDU designs seemed r.o offer small but significant reductions in power costs. These mainly resulted from lower heavy water inventory and higher thermal efficiency. However, the main reason for their introduction into the program was concern about heavy water leakage from the PHW. In 1971 the pressurized heavy water CANDU reactors at Pickering began their successful operation and confirmed that heavy water losses were low - less than one per cent of inventory per year. AECL then decided that the major programs necessary to prove the BLW and OCR alternatives commercially could not be justified and these alternative CANDU designs were not developed beyond the initial prototype stage. However, the higher temperature steam conditions from an OCR could make it a potential energy source for in-situ recovery of heavy oils from the Canadian tar sands. This possible use is one of Research Company's current interests, and may revive development of the CANDU-OCR.

Although the main objective in reactor development has been the production of electric power, some effort was devoted to development of a small, low-power reactor. This 20 kW thermal reactor is a research tool for neutron activation analysis and for production of short-lived isotopes. It is called SLOWPOKE - Safe LOW POwer Critical Experiment(20). Figure 17 illustrates the reactor layout. Its intrinsic safety and simple control stem from the fact that it has a strong negative temperature coefficient, and excess reactivity is rapidly overcome by the small rise in core temperature due to the initial power excursion. Figure 18 shows how power is inherently limited to a safe level after such an excursion, allowing the reactor to run unattended(21). The Radiochemical Company offers a commercial version of SLOWPOKt, and an uprated version is being evaluated as a possible method of heating large buildings.

In 1958 when the decision to build Douglas Point was taken, AECL formed a separate design group in which has become the Engineering Company. Full-scale testing of - 8 - prototype components for the CANDU nuclear steam supply system was essential. Thus, large engineering laboratories were established; these have been located at Sheridan Park since 1966 and are operated by the Engineering Company (Figure 19). Close collaborat n is maintained between this group and the workers at CRNL ai.3 WNRE dealing with power reactor component development.

As the program has evolved, the research and development manpower at AECL has shown two major periods of growth - see Figure 20. First, the early period as the program was established during the middle 1950's. Second, the middle sixties when WNRE was beginning to expand. Since then the research and development manpower in the company has remained fairly constant. As reactor development programs grew smaller, effort was shifted to heavy water processes, waste management and future fuel cycles. - 9 -

3. PROGRAM HIGHLIGHTS 3.1 Organization The research and development program of Research Company is organized by identifying objectives in each area of activity, then setting out a plan for achieving these objectives in realistic times according to available funding and manpower. The review of the plan is the responsibility of the R&D Program Committee, comprised of senior scientific and technical managers and chaired by the Executive Vice- President of Research Company, Mr. R.G. Hart. Six Steering Committees are charged with coordinating the work once the program plan has been approved by the President of AECL and its Board of Directors. There is a Steering Committee for each rrr-jor program area:

- Underlying and Advanced Systems (29%) - Power Reactor Systems (33%) - Heavy Water Processes (4%) - Environmental Protection and Management (24%) - Advanced Fuel Cycle (9%) - Assessments and New Applications (<1%) The figures in brackets indicate the current distribution of professional effort amongst the six areas, and Figure 21 shows how the work is distributed between the two laboratories. With both sites involved in most of the major programs, the Steering Committee structure also serves as an excellent means for maintaining close collaboration between CRNL and WNRE. The work in each major program area is subdivided among Working Parties, which coordinate specific work areas. The actual execution of the work is the responsibility of a separate line organization in which each site is divided into Divisions and Branches either according to function or by scientific and engineering discipline.

The R&D program structure permits the active pursuit of desired objectives, subject to continuing review and revision as needed to suit national or Company priorities. The area of Assessments and New Applications is currently small, but is being expanded to investigate other energy options, both nuclear and non-nuclear, where AECL technology might be put to use - an important example is to define ways in which nuclear energy can substitute for oil, and then to develop the required technology. - 10 -

As well as an increase in New Applications, the trends expected in the next decade are a decrease in development in the areas of Power Reactor Systems and Heavy Water Processes accompanied by increases in the areas of Environmental Protection and Radioactive Waste Management and the Advanced Fuel Cycle. 3.2 Underlying Research and Advanced Systems The underlying research work is divided into five program areas, and the following list outlines some of the major topics. . Radiation Biology: Effects of ionizing radiation on living organisms, mechanisms of repair of cell damage, long-term effects of radiation on natural plant and animal communities. . Environmental Research: Ground-water geochemistry, hydrogeology, tracer studies of the movement of in the environment and in food chains. . Physics: Structure of the nucleus and nuclear interactions using the MP Tandem Accelerator; properties of condensed matter and neutron scattering using the NRU reactor.

. Chemistry: Radiation chemistry, laser photochemical and catalytic methods of isotope separation, actinide and fission product chemistry, analytical chemistry. . Materials Science: Radiation damage, surface phenomena related to corrosion, role of line and point defects in deformation. Major AECL contributions in the biological field include studies on the biological effects of radiation in cells, plants and animals; epidemiology of radiation; population genetics; and the interaction of radionuclides with the environment(22-25). A recent highlight of the biomedical work was the publication of research results on the radiation sensitivity of cells from parents of victims of the rare hereditary disease ataxia telangiectasia, indicating that radiation sensitivity is influenced by hereditary factors(26).

The CRNL Perch Lake area (Figure 22) is one of the world's best experimental areas for studying the movement of radionuclides in a natural environment. The knowledge gained in these studies has led to improved methods of assessing the environmental impacts of high and low level waste management - 11 -

through pathways analysis. The movement of radionuclides in this lightly contaminated aquatic ecosystem has been studied for many years(27). Figure 23 is a simplified illustration of the concentration of cobalt-60 in the water, the sediment and along typical food chains. The highest concentration factors are found in the herbivores such as snails, with much lower factors for the higher carnivores such as adult perch. Perch Lake has been used extensively for hydrological, geological and geochemical studies to evaluate its performance as a waste management area, as a part of Canada's contribution to the International Hydrological Decade(28), and as part of the UNESCO International Hydrological Program(29). Research in fundamental particle behaviour is centered around a major CRNL research facility, the tandem accelerator(12) (Figure 24). The 20 MeV Chalk River MP Tandem Accelerator complex is a world-class laboratory. It is the leading Canadian laboratory for low-energy/heavy-ion physics and will soon be upgraded by the addition of a superconducting cyclotron. Radiative lifetimes of nuclear levels in the 10 to 10 second range can be measured accurately by the Doppler shift attenuation method and the recoil distance plunger method(30). These methods, as well as direct timing and other methods, were pioneered at CRNL and are now used worldwide to obtain information about the excitation modes of nuclei throughout the periodic table. A systematic and precise study has been done of a class of very fast nuclear beta decays (superallowed beta decays)(31). Results have verified a fundamental conservation law and tested contemporary theories of the weak interaction. The studies of beta-delayed proton decays have found exotic new isotopes and permitted detailed spectroscopy. A new field of nuclear research has been opened up closely associated with the study of heavy-ion reactions. Since collisions between two heavy nuclei are especially effective in producing compound systems with large angular momentum, it is now possible to study rapidly rotating nuclear systems and explore new aspects of nuclear dynamics. Physicists at CRNL and their collaborators are at the forefront of this new field and have made major discoveries(32,33).

To maintain the competitive position of Canada in the heavy- ion field and keep nuclear research at CRNL at the forefront, the MP Tandem facility is being upgraded by the addition of a superconducting cyclotron. The cyclotron takes heavy ions from the MP and accelerates them to high enough energies to permit study of the bombardment of any target with any ion, - 12 -

opening up a vast, unexplored region. This new facility is being developed and designed by staff at CRNL. Facilities such as the Perch Lake basin or the Tandem Accelerator are extensively used by scientists from outside CKNL, particularly those from Canadian universities. Thus, these unique facilities play an important part in the scientific life of the country extending beyond AECL's own mission.

The accelerator research is the base for new developments in nuclear power technology and in medical research(34). Like the fast breeder reactor and the thorium fuel cycle, the accelerator breeder offers the possibility of a many-fold increase in the amount of energy attainable from the world's uranium and thorium resources. In this concept (Figure 25), protons from an ion source are accelerated in a linear accelerator and impact on a heavy-element target (e.g. bismuth). By a complex set of reactions a large yield of is produced. These can be absorbed in uranium or thorium to produce , or uranium-233, respectively. Heat generated in the overall process can be recovered to produce electricity, and the plutonium or uranium-233 can be separated to produce fuel for power reactors. To be practical, proton beam powers of 300 MW (proton currents of 300 mA and 1000 MeV) must be achieved(35). Work to date on this advanced system has concentrated on the development of ion sources and accelerators to assess the practicality of reaching the required current and energy levels, and good progress is being made. In the interim, spinoff technology has produced a new accelerator, the turn-around LINAC for cancer therapy, Figure 26, which is now at the prototype stage in the Radiochemical Company. 3.3 Power Reactor Systems Work in this area provides continuing support for the CANDU- PHW reactor program. The goal at this stage is to extend and consolidate the underlying science and technology which form the basis for design, operation, manufacture and regulatory control. About one third of this program is related to reactor safety. It will provide a much broader range of data and better theoretical understanding for predictions of system behaviour during postulated accidents and for verifying accident analysis codes. This should permit more accurate safety assessments and better define current safety margins; as a result some relaxation of design limits may become possible while maintaining the required level of safety. - 13 -

Other parts of the power reactor systems program, mainly done on contract for the Engineering Company or the utilities, are aimed at reducing capital or operating costs and increasing reliability so that the cost of electricity to the consumer remains low. Each percent increase in capacity factor is currently worth about twelve million dollars per year for the Canadian nuclear power stations now committed.

Work in this area involves close collaboration wich designers and operators, especially in setting objectives and priorities. Excellent rapport exists between the laboratories and the Engineering Company, the utilities and the manufacturers. An essential final step in each development program is to transfer the results to the appropriate parts of the nuclear industry. The work on power reactor systems is divided into six program areas having the following major topics: . Fuel Channels - creep and growth of pressure tubes and calandria tubes, effects of deuterium on zirconium alloy properties, new zirconium alloys . Out-reactor Components - nondestructive methods of inspection, improved valve performance, pump seal reliability, steam generator technology . Systems Chemistry - corrosion, activity transport in heavy water circuits, decontamination . Heat Transfer (thermalhydraulics) - critical heat flux, system behaviour during a loss of accident am". during a loss of emergency coolant accident . Reactor Physics and Control - reactor transient behaviour, multivariable control, flux monitors, electronics for distributed systems, instrumentation . Fuel - power cycling, defect behaviour, performance under postulated accident conditions Work on out-reactor components is successfully improving reliability and maintainability of valves, pumps, steam generators and heat exchangers. The development of a live- loaded packing for valve stems is an excellent example. As shown in Figure 27, live-loading consists of adding ssprings to maintain a constant load on the packing of control valves and gate valves. Low leakage rates are maintained, reducing the flow of heavy water to the collection system from between the primary and secondary packing. Even more important, - 14 -

live-loading drastically reduces the frequency of retorquing to reseal the packing, thus avoiding maintenance in areas having significant radiation fields. This concept w,as developed and proven at CRNL in the early seventies(36). The valves at the Pickering Generating Station were modified after start-up with the results shown in Figure 28 - the total savings in maintenance costs have been one million dollars annually. The technology has been transferred to Canadian industry and is applied in all CANDU stations. Figure 29 illustrates one of the four steam generators installed in a 600 MW CANDU station. It is about 20 m high and 2 m in diameter and contains some 60 km of 1.6 cm diameter Incoloy tubing. Experimental investigations of vibration, corrosion and heat transfer are conducted at CRNT-i. An important achievement has been the development of computer codes for design and analysis}37,38). A typical output of the THIRST code - Thermal hydraulic analysis Iji Recirculating STeam generators - is given in Figure 30 showing velocity and quality contours. The performance of CANDU steam generators has been excellent(39): only 61 tubes have had to be plugged out of a total of 3 x 10 in 50 effective full-power years of reactor operation in Canada. This reflects careful quality control in manufacture and detailed attention to boiler water chemistry(40). An example of our work on non-destructive inspection systems is the development of CANSCAN which CRNL, in collaboration with Bristol Aerospace and Canadian Astronautics Limited, undertook on contract to Ontario Hydro(41). The system has been completed and delivered to Ontario Hydro. The essential components are illustrated in Figure 31. Tube inspection is done automatically by a pair of eddy current probes at 0.5 m/s. Thus, a steam generator containing 2600 tubes can be inspected in 48 hours. A tube-sheet walker (Figure 32) is programmed to traverse the tube-sheet lattice in a step-by-step manner carrying the probes and cables. The entire system is controlled remotely from a trailer outside the reactor building. A single coaxial cable carries all control signals, inspection data and communications information. Digital control and data processing provide in real time a display of all unexpected eddy current signals in a convenient form for visual analysis. Detection limits are a through-wall hole of 0.34 mm diameter and fretting wear 0.14 mm deep.

The systems chemistry program includes experiments and development of models for predicting corrosion and activity transport in the primary heat transport systems for a range of chemistry conditions(42 ,-*3) . As a result of this program, - 15 -

the relationship between coolant chemistry and corrosion is well understood and CANDU reactor operators maintain conditions which minimize both corrosion and activity transport problems. Even very thin deposits of corrosion products on the fuel sheath surface can yield significant radioactivity, mainly cobalt-60, which may be transferred to out-core surfaces by dissolution and then precipitation or exchange. The resulting radiation fields may interfere with maintenance work during shutdowns.

An important chemical technique to reduce radiation fields due to corrosion products is the CAN-DECON decontamination process developed jointly by CRNL and WNRE(44). This uses a dilute reagent mixture which can be added to heavy water without introducing any ordinary water. The reaqent dissolves and disperses corrosion products, and as the primary heat transport system heavy water is circulated through cation exchange resin, metallic ions are removed and the reagent regenerated. The corrosion products and associated radioactivity are retained on the resin for which handling and disposal techniques are already available. The reagent can be removed from the circuit by mixed-bed ion exchange. A full-scale decontamination of the Douglas Point reactor was done in 1975 (45) reducing fields associated with carbon steel piping by a factor of six. A Canadian company, London Nuclear Decontamination Limited, has been licensed to apply this technology worldwide, and have decontaminated systems in two boiling water reactors in the United States. Figure 33 shows how total annual external man-rem doses to operating staff at CANDU stations have been controlled and reduced(46). The figure shows annual rem per installed electrical MW; thus, the small size of NPD results in a large value of rem/(MWe-a). The high radiation fields in the early years at Douglas Point, '-/hich were increasing rapidly by 1971, sparked a large program aimed at reducing these fields and the resulting man-rem doses, and also aimed at understanding the controlling phenomena so that activity transport could be controlled. Decontamination and improved chemistry control achieved the first goal. Strict adherence to good chemistry control, using materials v/ith a low cobalt impurity content, improved station layout and reduced maintenance requirements have all contributed to the low man-rem doses at Pickering and Bruce. The doses at Pickering in 1974 and 1975 were increased by the need to replace 69 cracked pressure tubes in units 3 and 4(47).

Extensive irradiation facilities at both CRNL and WNRE, referred to as 'loops', provide separate pressurized heat transport systems passing through the research reactor - 16 - cores(8). They provide for testing of fuel behaviour under irradiation, dynamic measurement of creep and growth of experimental pressure tubes, and the chemical and thermal- hydraulic behaviour of the coolant fluid at power reactor conditions of pressure, temperature and flow. Figure 34 shows the U-l loop in the NRU reactor at CRNL which is connected to two full-size fuel channels i.i series producing twelve MW of heat. It can operate with either pressurized water or boiling water, and accommodate a total of twelve full-size fuel bundles. There are similar facilities for testing outside the reactors, including a large freon loop for critical heat flux studies.

Equally important are the post-irradiation examination facilities for detailed analysis of irradiated fuel and other materials(48). Figure 35 shows the metallographic examin- ation of a cross section of an irradiated fuel element at CRNL. In Figure 36 an operator uses remote manipulators to handle highly radioactive material in shielded cells at WNRE. As mentioned earlier, the operation of large test reactors and their associated experimental equipment requires a large support staff which includes about one third of the professional manpower of the laboratory - the Operations Group. These people are thoroughly familiar with the design, control and maintenance of the research facilities and are responsible for safety and scheduling as well as operation. An effective and productive experimental program is achieved through close cooperation and teamwork by the researchers and Operations. The research and development in the areas of fuel and fuel channels are described in a companion report by J.R. MacEwan (49). The heat transfer program is aimed at measuring critical heat flux in horizontal fue1. channels and thus improving the accuracy of the prediction of critical channel power for CANDU reactor designs. The program also includes developing fuel bundle designs capable of higher power output. An important achievement in 1973 in the CANDU-BLW program was to measure the heat transfer behaviour of nuclear fuel in the U-l loop including operation beyond dryout (50). However, extrapolating the critical heat flux results from this experiment to horizontal channels, especially at reduced flow conditions, is uncertain. Therefore, a major program of measurements in a full-scale horizontal channel out-of-reactor was launched (Figure 37). The U-l loop is used to provide flow and a heat sink. The simulated series - 17 -

of 37-element fuel bundles are heated electrically (Figure 38) requiring up to eleven MW of power. The current experiment has a uniform axial heat flux, and a radial distribution in the bundle to simulate the flux depression toward its centre. Construction is in progress of an electrically heated simulated series of bundles with a cosine-shaped axial heat flux. Sophisticated instrumentation has been developed to measure pressure drop, sheath temperature, detect dryout and the corresponding critical heat flux, and also to measure post-dryout heat transfer. Work in this large facility is complemented by more basic studies in water and freon{51), including bundle tests in freon(52). Here the effects of a large range of variables can be studied at lower power and much more cheaply than in pressurized water.

At WNRE a pressurized water out-reactcr loop, RD-12 (Figure 39), is used to investigate system behaviour during a loss of coolant situation as a function of break size and location, power level, etc. The layout of the loop simulates a CANDU-PHW primary circuit with two electrically heated fuel channels (2 MW). A larger facility incorporating full-scale channels is planned. Experimental results are compared with predictions by computer programs, and are used to develop more accurate predictive models(53). A key factor is to develop adequate models for two-phase flow, which occurs throughout the system. Void fraction measurements by gamma densitometers provide average values - instruments to determine local void fraction are being developed. The research and development in the area of reactor physics and control are described in a companion report by J.B. Slater(54). 3.4 Heavy Water Processes Three plants produce heavy water in Canada, located in Nova Scotia and Ontario. Their total nominal capacity is 2400 Mg/a. The research and development at CRNL is aimed at improving reliability and production rate(55). Figure 40 shows the 400 Mg/a Port Hawkesbury Heavy Water plant in Nova Scotia which started production in 1970. It is operated by the AECL Chemical Company. Because of the low concentration of deuterium in nature (D/H of 1.5xiO~4 atom ratio) large masses of water must be processed. Thus, the first stage of the plant consists of three towers in parallel, each 9 m diameter and 90 m high. The process is based on the exchange of deuterium between water and hydrogen sulfide flowing countercurrently in the towers and repeatedly - 18 -

mixed on about one hundred sieve trays. Operation of the upper and lower sections of the towers at 300 K and 400 K, respectively, provides the driving force for heavy water extraction and requires a large energy input(56). Steam is supplied from back-pressure turbines at the adjacent electric power plant appearing in the background of Figure 40. Good sieve tray operation is the key to efficient production. Figure 41 is a schematic diagram of a two-pass tray used in these plants, illustrating the horizontal flow of water across each tray and the upward flow of gas through thousands of holes in each tray. Figure 42 gives a typical prediction of tray efficiency as a function of gas flow rate for a hot tower tray. This is based on pilot plant tests at CRNL, measurements of tray hydraulics using air and water and data from plant operation(57). The foamy nature of the process has required extensive testing to define optimum tray design. Another area of process development is hydrogen isotopic exchange between hydrogen gas and water promoted by a wet- proof catalyst developed at CRNL(58). The process can be used to recover by-product heavy water from electrolytic hydrogen, in combination with cryogenic distillation of deuterium to remove from heavy water, and in combination with electrolysis to reconcentrate heavy water which has leaked from reactors and become mixed with ordinary water.

3.5 Environmental Protection and Waste Management Nuclear power produces two types of wastes: . Radioactive fission products, plutonium and other actinide elements contained in irradiated fuel . Dilute radioactive liquid and solid wastes arising from reactor operation The goals of the environmental protection and waste management program are to demonstrate that these wastes can be disposed of safely, and to develop the methodology to assess the environmental and health effects of their management and disposal. A key element is the development of theoretically sound and experimentally verified computer programs which will predict any release of radioactive material from a waste repository, its transport within the environment and its uptake by, and effect on, man. The repository will be designed to ensure that such effects are negligible. - 19 -

The reactor wastes contain only a small fraction of the total radioactivity, but are considerably larger in volume than the fuel wastes. The reactor wastes are lovz-level wastes. Figure 43 shows schematically the operations of the CRNL Waste Treatment Centre which is currently being commissioned. It will develop and demonstrate the technology for reactor waste treatment and immobilization, converting the wastes into stable, leach-resistant forms. The key steps are to concentrate the waste, by incineration of combustibles and by reverse osmosis and evaporation for the aqueous streams, and then to combine these concentrates with bitumen and place the product in a container for storage. A pilot plant program is nearing completion!59) to define each step and evaluate its effect on the stability of the final bituminized product.

Irradiated CANDU fuel bundles are stored in water-filled bays at the reactor sites (Figure 44). A covering of four metres of water above the stored fuel is sufficient to reduce radiation to an acceptably safe level. One hundred and sixty thousand bundles are now in storage resulting from the generation of 1.9X1011 kW»h of electricity. This procedure has proved both effective and inexpensive, and there is experience in Canada with fuel storage over a period of seventeen years(60). Since it is unlikely that any large quantity of irradiated fuel will be prepared for final disposal before 2000, interim storage will be needed for several more decades(61). This could be in the form of additional water-filled bays at each nuclear station or a central storage facility. Presently committed storage space is adequate until at least 1988. Ontario Hydro is investigating three concepts!62): a large water-filled pool of modular construction, dry storage in concrete canisters based on developments at WNRE (Figure 45) (63), and dry storage in a large concrete vault cooled by convection.

The fuel cycle waste management program is a major part of WNRE's activities. The goal is to develop and demonstrate technology for: . Immobilization of irradiated fuel wastes, either as intact fuel or as separated fission product wastes, in a leach-resistant matrix . Isolation of the immobilized wastes from the biosphere for their hazardous lifetimes. Figure 46 illustrates the two options for closing the natural uranium fuel cycle: treat the irradiated fuel as a waste for - 20 -

disposal, or recover its plutonium content for further power generation and dispose of the true wastes - the fission products and some actinides. Whichever option is finally adopted by the Canadian government, suitable waste disposal technology will be available since the AECL program addresses the requirements of both. Work on immobilisation of intact irradiated fuel is investigating two alternative systems: simple containment that will provide immobilization for at least 300 years while most of the radioactivity decays, and a more complex system which will provide immobilization tor a much longer period. The latter will only be taken beyond the conceptual stage if analysis shows the simple system to be inadequate. One possibility being investigated for the simple system is encasement of the fuel bundle in a lead matrix contained in a thin, corrosion-resistant shell. Work on immobilization of separated fission product wastes, which will also contain some actinide elements, is concentrated on fixation into glass and other ceramics. Of particular interest are the effects of temperature, water and radiation on the properties of the glasses(61). Very encouraging results were provided by a study involving glass blocks, containing fission products, which were buried at the Chalk River site twenty years ago in wet, sandy soil. Monitoring over the years showed little movement of radio-nuclides through the soil, the strontium-90 front moving only 33 m in 11 years. The leaching rate of strontium-90 from the blocks fell sharply in the first two years, reaching a constant value after six years(64), as illustrated in Figure 47. The total amount of radioactive material which has left the glass in twenty years is only one part in one million. Recent examination of a glass block in a shielded cell showed it to be in excellent condition. The first phase of the waste disposal program will verify that the concept of placing the immobilized wastes deep underground in a stable geological formation can achieve effective isolation from the biosphere. The second phase of the program is to select a site for a demonstration disposal facility which might be in operation by about 1990. Site selection will involve a wide range of technical, social and political considerations. The third phase of the program is to construct and operate the Demonstration Facility.

Concept verification involves geological, geophysical and geochemical studies, as well as an extensive drilling program, and these are in progress(65). Figure 48 illustrates the conceptual design of a waste repository in hard rock. - 21 -

3.6 Advanced Fuel Cycle Research in this area is aimed at developing a secure long- term fuel supply for Canada in the next century, by investigating the development and introduction of alternatives to the current once-through fuel cycle for natural uranium. The program includes laboratory-scale studies of fuel reprocessing to recover fissile materials; plutoniurn-uranium, plutonium-thorium and uranium-thorium fuel fabrication; and the reactor physics of CANDU reactor cores based on the thorium fuel cycle. Figure 49 shows the distribution of professional effort in this program.

The characteristics of the fuel cycles and the economic factors involved, as well as their potential impact on resource utilization, are discussed by J.B. Slater(54). The lead time to develop and demonstrate the thorium fuel cycle technology is about twenty years. Thus, although thorium fuelling of CANDU power stations is unlikely before 2000, the research and development has already begun. AECL has provided the major technical input for Canada's participation in the International Evaluation. The INFCE results would appear to support the orderly growth of AECL's nuclear fuel cycle program as governed by need and the development of satisfactory safeguards measures. The fuel reprocessing work includes testing the feasibility of alternative flow sheets for the reprocessing of thorium fuels, improving the accuracy of the estimates of fuel reprocessing costs, and providing small amounts of separated wastes for the waste immobilization studies that form a pa^t of the Radioactive Waste Management program. A major feature of the reprocessing work is a small-scale experimental facility in the WNRE shielded cells to test flow sheets with irradiated materials.

The goal of the fuel fabrication work is to demonstrate the feasibility of safely fabricating recycle fuels which meet the performance requirements of advanced fuel cycles. The primary difference between these cycles and the natural uranium cycle is the higher burnup of the former (up to 700 MW-h/kg vs. 180 MW-h/kg). Fabrication techniques for recycle fuels also differ since recycle plutonium is toxic and mildly gamma-active while recycle uranium-233 is toxic and sufficiently gamma-active that remote fabrication will probably be required. The reference fuel fabrication method is standard oxide pellet technology, in glove boxes for plutonium-enriched fuel anr"1 in fully remote facilities for uranium-233.

An experimental recycle fuel fabrication laboratory (Figure 50) was built at CRNL to fabricate small quantities - 22 - of plutonium fuels for physics experiments and test irradiations under power reactor conditions, and to provide data on safety and fabrication procedures. An extensive commissioning program, in which 40 natural uranium dioxide bundles were fabricated, was carried out before plutonium was introduced in September 1978. The fabrication of 15 (U,Pu)O2 fuel bundles was completed in early 1980. The bundles met power reactor specifications and were produced with no environmental release of radionuclides and very little radiation exposure to operators. Excellent fissile material accountability was achieved. The fabrication equipment will be modified slightly for the production of 40 (Th,Pu)O2 fuel bundles starting in 1980. 3.7 Technology Transfer A major goal of the Research Company has always been, and remains, the transfer of technology to utilities, design consultants, manufacturers, universities, and regulatory bodies so that this technology can be put to use. To date this transfer of technology has resulted in a Canadian industry which employs 30,000 people and has an entirely Canadian infrastructure. The Canadian content of a CANDU nuclear power station built in Canada is eighty per cent of its capital cost. At present the industry is located primarily in Ontario where nuclear energy produced about 35 percent of the electricity generated in 1979. There are components of the nuclear industry already established in Nova Scotia, New Brunswick, Quebec, and . Nuclear generating programs have begun in Quebec and New Brunswick. Current forecasts for installed nuclear capacity are in the range 25 to 45 GWe by 2000.

Technology will have to be transferred to each new utility as it enters the nuclear field and to additional consultant, manufacturing and university personnel in the other provinces. This technology transfer requires a major effort and expenditure which is not generally recognized, but is vital to the objective of putting technology to use in the building of our industry(66). It is accomplished through making available detailed internal proprietary reports, by accepting attached staff at the laboratories, by providing technical consultants and through licensing agreements.

Technology transfer is also an important factor in export sales. All countries importing nuclear technology wish to develop an industrial structure of their own similar to that being developed in Canada. Thus, technology transfer is usually a significant aspect of sales agreements. - 23 -

3.8 International Collaboration Earlier we mentioned the international collaboration at the basic science level. This occurs through exchange of staff for prolonged visits, cooperative experiments in which our unique facilities complement those elsewhere and a wide-ranging exchange of information at the working level. There have been a number of formal agreements to exchange information on various parts of the nuclear power program with many countries. The two most extensive exchanges have been with the United States and with the United Kingdom.

For over thirty years Canada has had a very broad agreement with the U.S. to collaborate in the field of nuclear energy. This has been primarily implemented between the United States Atomic Energy Commission (now part of the Department of Energy) and AECL. Important results of this collaboration include a transfer to the U.S. of our early heavy water reactor design and operating experience which became the basis for the large production reactors at Savannah River; a transfer to Canada of extensive U.S. experience on heavy water production to form the basis for the first generation of Canadian plants; the construction and operation for Bettis Atomic Power Laboratory of loops in the NRX reactor in which much fuel development for the U.S. naval reactor program was done; and exchange of results on many topics of nuclear power development. With the UK there have been two important periods of collaboration involving joint experimental programs. First there was early work at CRNL on irradiated fuel processing to recover plutonium. Then in the 1960-5 period several loops in NRX were used jointly for fuel, materials and chemistry experiments in support of the CANDU-BLW and the similar Steam Generating Heavy Water reactor being built in Britain. A current area of important international collaboration is nuclear fuel waste management. While Canada is concentrating on disposal in hard rock formations, we are able to assess development of other concepts, such as disposal in salt formations, through such collaboration. - 24 -

4. SUMMARY

The Research Company of the federally owned Crown Corporation, Atomic Energy of Canada Limited conducts both basic and applied research and development to support AECL's mission to produce the greatest benefit for Canada from the peaceful uses of atomic energy and related technologies. It acts as Canada's national laboratory for atomic energy. The Research Company program provides a coherent technological base for the whole Canadian nuclear industry, except uranium production.

This paper describes the breadth and scope of the program, outlines its evolution and illustrates recent accomplishments through a series of brief highlights. The program spans the whole spectrum from basic nuclear science to large-scale engineering development. One of AECL's major strengths is the ability to assemble large multi- disciplinary teams of scientists and engineers to work on a wide range of projects. At the same time AECL has been able to exercise the internal discipline to focus its program on a single reactor type. This narrow focus, backed by a strong fundamental scientific base, enabled Canada to develop a successful nuclear power system with a relatively small total research and development effort. The Research Company has two laboratory sites, the Chalk River Nuclear Laboratories and the Whiteshell Nuclear Research Establishment, with three large, high-flux research reactors. The total staff is 3100 and the 1979/80 budget was 140 million Canadian dollars. This rate of expenditure is a third of that in France and a tenth of that in the United States on research and development for civil nuclear programs. The evolution of the program shows how the early experience with large heavy water research reactors provided a sound basis for the CANDU nuclear power system. The path from NRX, which began operation in 1947, to the 3000 MWe Bruce Generating Station of today can be clearly delineated. Two alternatives to the highly successful pressurized heavy water CANDU design, the organic cooled CANDU and the boiling light water CANDU, were developed to the stage of initial prototype operation. However, they were not sufficiently attractive to justify further development at that time. The research and development program has six major areas: - underlying research and advanced systems - power reactor systems - heavy water processes - 25 -

- environmental protection and radioactive waste management - nuclear fuel cycle - assessments and new applications Both laboratory sites are involved in most areas, and the committee structure used to coordinate work in each area also serves to maintain close collaboration between CRNL and WNRE. Underlying research spans radiation biology, environmental research, physics, chemistry and materials science. The Perch Lake basin at CRNL has been used for extensive hydrological, geological and geocheinical studies as well as for studying movement along pathways in a natural aquatic ecosystem. Work in physics is centered around studies of the nucleus using the MP Tandem Accelerator and investigations of the solid state using neutron beams from the NRU research reactor. The major advanced system work is on accelerators and their application to breeding fissile material by spallation in a heavy element target, such as bismuth, surrounded by uranium or thorium. The spallation reaction would be initiated by a high current of BeV protons.

Power reactors systems work provides the foundation of science and technology for design, manufacture, operation and regulatory control of CANDU reactors. A large part of the program is related to reactor safety. There are six main topics: fuel channels, fuel, reactor physics and control, out-reactor components, systems chemistry and heat transfer. The first three are dealt with in separate papers by J.R. MacEwan and J.B. Slater. Work on out-reactor components is successfully improving reliability and maintainability of valves, pumps, steam generators and heat exchangers. Maintenance costs at the Pickering Generating Station were reduced by one million dollars per year by developing and installing live-loading on the packing of control valves. Experimental and theoretical studies have been used to develop the computer codes for steam generators which are required for design and performance analysis. CANDU steam generators have had an outstanding performance record - only 61 tubes have had to be plugged out of about three hundred thousand in 50 reactor- years of operation in Canada. Eddy current inspection of the tubes of a complete steam generator in 48 hours will be possible using a fully automated system (CANSCAN) now being commissioned. Data analysis proceeds simultaneously with the inspection.

A thorough understanding of coolant chemistry and corrosion product transport has enabled CANDU station operators to maintain low radiation fields in maintenance areas. - 26 -

Radiation doses to station operators are only about 0.3 man-rem/(MWe-a). Although it has not yet been necessary to decontaminate the heat transport system of the Pickering or Bruce reactors, a technique, referred to as CAN-DECON, has been developed. It is being applied by a Canadian company to light water reactors in other countries.

A major heat transfer program is to measure critical heat flux in a full-scale horizontal fuel channel using an electrically heated simulated string of 37-element fuel bundles. Up to eleven MW of power are required. Both axial and radial heat flux variations typical of a reactor channel are simulated. An essential final step in each development project is to transfer the results to the appropriate parts of the nuclear industry. This is facilitated by maintaining close collaboration with designers, operators or manufacturers as the work progresses.

Research and development on heavy water processes is aimed at improving the reliability and production rate of the three plants in Canada. An important achievement has been to understand and improve sieve tray performance in a process which is inherently foamy. New process development has concentrated in recent years on a new catalyst for hydrogen isotope exchange between hydrogen gas and water. It has several potential applications including recovering tritium from heavy water.

Environmental protection and waste management studies aim to demonstrate that the wastes from nuclear power production can be disposed of safely, and to develop the means to assess the environmental and health effects of their management. Low level wastes will be concentrated and incorporated in bitumen. CANDU fuel is currently stored in water-filled bays, and this can continue for several more decades. Procedures are being developed to immobilize either intact irradiated fuel or separated fission products; the option to be finally used depends on whether or not the government of Canada decides to recycle plutonium from irradiated fuel. Successful immobilization of fission products in blocks of glass has been demonstrated over a twenty-year period in a field experiment at CRNL. A program to demonstrate disposal of immobilized wastes deep underground in a hard rock formation is in its initial phase.

The development of uranium-plutonium and thorium-uranium fuel cycles for CANDU reactors is proceeding at the laboratory scale. Small quantities of recycle fuels are being fabricated for reactor physics studies and experimental - 27 -

irradiations. Introduction of thorium fuelling for CANDU power stations is unlikely before 2000. AECL has developed a nuclear power reactor system appropriate to Canada's industrial capabilities. The research and development program is consolidating and extending this achievement to help serve the world's energy needs far into the future. - 28 -

REFERENCES

The reference list has been selected to provide suitable starting points for readers interested in pursuing topics in more detail. Many of the papers have been published in journals and conference proceedings; they are also identified here by Atomic Energy of Canada Limited (AECL) reprint number. Both reports and reprints are available to the public, and enquiries should be addressed to:

Scientific Document Distribution Office Atomic Energy of Canada Research Company Chalk River Nuclear Laboratories Chalk River, Ontario, Canada KOJ 1J0 - 29 -

1. R.G. Hart and A.D.B. Woods. The AECL research and development program. Atomic Energy of Canada Limited, report AECL-6871 (1980). 2. R.M. Williams, H.W. Little, W.A. Gow and R.M. Berry. Uranium and thorium in Canada: Resources, production and potential. Paper A/CONF.49/P/154 presented at the Fourth U.N. International Conference on the Peaceful Uses of Atomic Energy, Geneva, 6-16 September 1971. Atomic Energy of Canada Limited, report AECL-3977 (1971). 3. J.A. Baron. Experience with the acoustic emission monitoring of a steam drum nozzle in a CANDU nuclear generating station. Publication No. 697, American Society of Testing Materials (1979). 4. R. Neufeld. Preparation du Z-pinch et mesures preliminaires des parametres du plasma pendant 1'interaction laser. Institut de recherche de I1Hydro-Quebec rapport IREQ-1772 (1978). 5. AECL Laser Fusion Working Party. A review of the prospects for laser induced thermonuclear fusion. Atomic Energy of Canada Limited, report AECL-4840 (1974). 6. R.E. Manson. The NRX reactor - A general description. Atomic Energy of Canada Limited, report AECL-2692 (1967). 7. J.W. Logie. Three vessel replacements at Chalk River. Atomic Energy of Canada Limited, report to be published. 8. D.J. Axford. Chalk River - supporting Canada's power reactor program. Nuclear Engineering International, 24(280):31-34 (1979). Atomic Energy of Canada Limited, reprint AECL-6470 (1979). 9. J.M. Beddoes. Recent developments in radiation equipment and radio-isotopes. Presented at the Canadian Nuclear Association Eighteenth Annual International Conference, Ottawa, Ontario, 11-14 June 1978. Atomic Energy of Canada Limited, report AECL-6350 (1978). 10. R.E. Manson. The NRU reactor. Atomic Energy of Canada Limited, report AECL-1897 (1964). 11. G.M. James. NRU reactor converts to enriched core. Canadian Nuclear Technology, 3(2);57-59 (1964). Atomic Energy of Canada Limited, reprint AECL-1967 (1964). - 30 -

12. G.A. Bartholomew, A.W. Boyd, J.A. Davies, J.W. Knowles, M.L. Swanson, P.R. Tunnicliffe, A.D.B. Woods and J.B. Warren. Some advanced research uses of Canadian reactors and accelerators. Atomic Energy of Canada Limited, report AECL-3907 (1971). 13. I.N. MacKay. The engineering design and operation of the NPD reactor. Reprint of papers given at the Winter Meeting of the American Nuclear Society, Washington, D.C., November 1962. Atomic Energy of Canada Limited, reprint AECL-1682 (1968). 14. L.R. Haywood. Evolution of . Address to 1967 Congress of Canadian Engineers, , May-June 1967. Engineering Journal, 50(10):49-53 (1967). Atomic Energy of Canada Limited, reprint AECL-2886 (1967). 15. G.A. Pon. Evolution of CANDU reactor design. Presented at the Canadian Nuclear Association Eighteenth Annual International Conference, Ottawa, Ontario, 11-14 June 1978. Atomic Energy of Canada Limited, report AECL-6351 (1978) .

16. D.G. Turner. The WR-1 reactor: a general description. Atomic Energy of Canada Limited, report AECL-4763 (1974). 17. R.O. Sochaski (ed.). The CANDU OCR power station options and costs. Atomic Energy of Canada Limited, report AECL-6436 (1980). 18. G.A. Pon. CANDU-BLW-250. Paper SM-99/32 presented at IAEA Symposium on Heavy Water Power Reactors, Vienna, September 1967. Atomic Energy of Canada Limited, reprint AECL-2942 (1968). 19. A.J. Mooradian. Reactor development (PHW, ABLW, OCR). Paper 72-CNA-401 presented at the Canadian Nuclear Association Twelfth Annual Conference, Ottawa, 11-14 June 197 2. Atomic Energy of Canada Limited, reprint AECL-4275 (1972) . 20. R.E. Jervis, J.W. Hilborn, R.E. Kay and R.G.V. Hancock. SLOWPOKE at the : Three years of progress. Paper CNA-74-205 presented at the Canadian Nuclear Association Fourteenth Annual International Conference, Montreal, 9- "> June 1974. Canadian Nuclear Association Report 74-CN. 200, CANDU Program and Research Installations. Atomic Energy of Canada Limited, reprint AECL-4902 (1974). - 31 -

21. R.E. Kay, J.W. Hilborn and N.B. Poulsen. The self-limiting power excursion behaviour of the SLOWPOKE reactor. Results of experiments and qualitative explanation. Atomic Energy of Canada Limited, report AECL-4770 (1976).

22. A.M. Marko, D.K. Myers, I.L. Ophel, G. ^owper and H.B. Newcombe. Research in radiation biology, in the environment and in radiation protection at CRNL. Atomic Energy of Canada Limited, report AECL-5911 (1 78). 23. D.K. Myers. Cancers and genetic defects resulting from the use of various energy sources. Atomic Energy of Canada Limited, report AECL-6084 (1978). 24. J.L. Weeks. A registry for the study of the health of radiation workers employed by AECL. Atomic Energy of Canada Limited, report AECL-6194 (1979). 25. D.K. Myers and H.B. Newcombe. Nuclear power and low level radiation hazards. Presented at the Canadian Nuclear Association Symposium on CANDU Reactor Safety Design, November 1978. Atomic Energy of Canada Limited, report AECL-6482 (1978). 26. M.C. Paterson and P.J. Smith. Ataxia Telangiectasia: An inherited human disorder involving hypersensitivity to ionizing radiation and related DNA-damaging chemicals. Annual Review of Genetics, 13;291-318 (1979). Atomic Energy of Canada Limited, reprint AECL-6619 (1979).

27. I.L. Ophel and CD. Fraser. The fate of cobalt-60 in a natural freshwater ecosystem. Ln Radionuclides in Ecosystems, Proceedings of the Third National Symposium on Radioecology, May 1971. p.323-327. Atomic Energy of Canada Limited, reprint AECL-4627 (1973). 28. P.J. Barry (ed.). Hydrological studies on a small basin on the Canadian Shield. Atomic Energy of Canada Limited, report AECL-5041 (1975). 29. P.J. Barry (ed.). Hydrological and geochemical studies in the Perch Lake Basin. Atomic Energy of Canada Limited, report AECL-5936 (1977). 30. T.K. Alexander and J.S. Forster. Lifetime measurements of excited nuclear levels by Doppler-shift methods. In Advances in Nuclear Physics, Vol. 10, Ch.3, p.197-333 (1978) . - 32 -

31. J.C. Hardy and I.S. Towner. Superallowed 0+-—>-0+ nuclear fl-decays and Cabibbo universality. Nuclear Physics, A254;224-240 (1975). Atomic Energy of Canada Limited, reprint AECL-5265 (1975). 32. D. Horn, 0. Hausser, B. Haas, T.K. Alexander, T. Faestermann, H.R. Andrews and D. Ward. High spin yrast states in N-126 isotones. Nuclear Physics, A317:520-534 (1979). Atomic Energy of Canada Limited, reprint AECL-6464 (1979). 33. T.L. Khoo, R.K. Smithers, B. Haas, 0. Hausser, H.R. Andrews, D. Horn and D. Ward. Yrast traps and very high spin yrast states in -^Dy. Physical Review Letters, 41(15):1027-1030 (1978). 34. S.O. Schriber, J.S. Fraser and P.R. Tunnicliffe. Future of high intensity accelerators in nuclear energy. Presented at the 10th International Conference on High Energy Accelerators, Serpukhov/Protvino, USSR, 11-17 July 1977. Atomic Energy of Canada Limited, report AECL-5903 (1977). 35. G.A. Bartholomew, J.S. Fraser and P.M. Garvey. Accelerator breeder concept. Report INFCE/WG.8/CAN/DOC1. Atomic Energy of Canada Limited, report AECL-6363 (1978). 36. D.F. Dixon. Solving the problem of valve steam leakage. In AECL research and development in Engineering. Special Edition 1976. p.3-7, Atomic Energy of Canada Limited, report AECL-5550 (1976). 37. M.J. Pettigrew. A comprehensive approach to avoid vibration and fretting in heat exchangers. ASME Pressure Vessels and Piping Conference, San Francisco, 1980 August 13-15. (To be published.) 38. W.W.R. Inch. Thermal-hydraulics of nuclear steam generators: Analysis and parameter study. ASME Nuclear Engineering Division Conference, San Francisco, 1980 August 18-21. (To be published.) 39. O.S. Tatone and R.S. Pathania. Steam generator tube performance: Experience with water-cooled nuclear power reactors during 1978. Atomic Energy of Canada Limited, report AECL-6852 (1980). 40. D.P. Dautovich and G.F. Taylor. Steam generator experience with CANDU pressurized water reactors. Atomic Energy of Canada Limited, report AECL-6842 (1980). - 33 -

41. R.I. Hodge, J.E. LeSurf and J.W. Hilborn. Steam generator reliability - Canadian practice. Jji Reliability Problems of Reactor Pressure Components, Vol. II, International Atomic Energy Agency, Vienna (1978), p.177-197. Atomic Energy of Canada Limited, reprint AECL-6253 (1978). 42. D.H. Lister. The growth of radiation fields around CANDU boilers. Activation Processes (R&D), p.169-176 (1977 ) . Atomic Energy of Canada Limited, reprint AECL-5774 (1977). 43. D.H. Lister. Mechanisms of corrosion product transport and their investigation in high temperature water loops. Paper 153 presented at Corrosion/78, The International Corrosion Forum Devoted Exclusively to the Protection and Performance of Materials, Houston, Texas, 6-10 March 1978. Atomic Energy of Canada Limited, reprint AECL-6257 (1978). 44. B. Montford. Cycling decontamination techniques at Douglas Point Generating Station - their evolution and recommended practice. Atomic Energy of Canada Limited, report AECL-4223 (1973). 45. P.J. Pettit, J.E. LeSurf, W.B. Stewart, R.J. Strickert and S.B. Vaughan. Decontamination of the Douglas Point reactor by the Can-Decon process. Materials Performance, 19(1):34 (1980). 46. J.E. LeSurf. Control of radiation exposures at CANDU nuclear power stations. Journal of the British Nuclear Energy Society, 16(1):53-61 (1977). Atomic Energy of Canada Limited, reprint AECL-5643 (1977). 47. E.C.W. Perryman. Pickering pressure tube cracking experience. Nuclear Energy, 17(2):95-105 (1978). Atomic Energy of Canada Limited, reprint AECL-6059 (1978). 48. E. Mizzan and R.J. Chenier. Facilities for post-irradiation examination of experimental fuel elements at Chalk River Nuclear Laboratories. Atomic Energy of Canada Limited, report AECL-6591 (1979). 49. J.R. MacEwan. Research and development for CANDU fuel channels and fuel. Presented to the Chinese Nuclear Energy Society, Peking, May 1980. Atomic Energy of Canada Limited, report AECL-6953 (1980). 50. D.C. Groeneveld and G.D. McPherson. In-reactor post-dryout experiments with 36-element fuel bundles. Atomic Energy of Canada Limited, report AECL-4705 (1973). - 34 -

51. M. Merilo and S.Y. Ahmad. The effect of diameter on vertical and horizontal flow boiling crisis in a tube cooled by Freon-12. Atomic Energy of Canada Limited, report AECL-6485 (1979). 52. D.C Groeneveld and S.R.M. Gardiner. Post-CHF heat transfer under forced convective conditions. In. Jones, O.C., Jr. and Bankoff, S.G. (eds.). Symposium on the Thermal and Hydraulic Aspects of Nuclear Reactor Safety. Volume I: Light water reactors. The American Society of Mechanical Engineers, New York, N.Y. 10017 (1977). Atomic Energy of Canada Limited, reprint AECL-5883 (1978) . 53. R.E. Nieman. Transient heat transfer and fluid mechanics associated with the loss-of-coolant accident. Paper presented at the CNA Symposium on Research on Radiological Safety in the Nuclear Fuel Cycle, 1979. (To be published.) 54. J.B. Slater. Research and development experience - the physics of CANDU reactors. Presented to the Chinese Nuclear Energy Society, Peking, May 1980. Atomic Energy of Canada Limited, report AECL-6960 (1980). 55. A.R. Bancroft. Heavy water GS process R&D achievements. Presented at the CNA Eighteenth Annual International Conference, Ottawa, 11-14 June 1978. Atomic Energy of Canada Limited, report AECL-6215 (1978). 56. H.K. Rae. Selecting heavy water processes. Ij2 Rae, H.K. (ed.). Separation of Hydrogen Isotopes, American Chemical Society, ACS Symposium Series No. 68 (1978) p.1-26. Atomic Energy of Canada Limited, reprint AECL-6054 (1978). 57. K.T. Chuang. Mass transfer modelling for GS heavy water plants. Presentation at the American Institute of Chemical Engineers, San Francisco, 1979. (To be published.) 58. M. Hammerli, W.H. Stevens and J.P. Butler. Combined electrolysis catalytic exchange (CECE) process for hydrogen isotope separation. Ij-i Rae, H.K. (ed.). Separation of Hydrogen Isotopes, American Chemical Society, ACS Symposium Series No. 68 (1978), p.110-125. Atomic Energy of Canada Limited, reprint AECL-6056 (1978).

59. D.H. Charlesworth, W.To Bourns and L.P. Buckley. The Canadian development program for conditioning CANDU reactor wastes for disposal. Presented at Radwaste Systems Session ASME/CSME Pressure Vessels and Piping Conference, Montreal, 25-29 June 1978. Atomic Energy of Canada Limited, report AECL-6344 (1978). - 35 -

60. C.E.L. Hunt and J.C. Wood. Long-term storage of fuel in water. Atomic Energy of Canada Limited, report AECL-6577 (1979). 61. J. Boulton (ed.). Management of radioactive fuel wastes: the Canadian disposal program. Atomic Energy of Canada Limited, report AECL-6314 (1978). 62. R.W. Barnes. The management of irradiated fuel in Ontario. Ontario Hydro report GP-76014 (1976). 63. M.M. Ohta. The concrete canister program. Atomic Energy of Canada Limited, report AECL-5965 (1978). 64. W.F. Merritt. High level waste glass: field leach test. Nuclear Technology, 32:88-91 (1977). Atomic Energy of Canada Limited, reprint AECL-5573 (1977). 65. J. Boulton and A.R. Gibson (eds.). First annual report of the Canadian nuclear fuel waste management program. Atomic Energy of Canada Limited, report AECL-6443 (1979). 66. E.C.W. Perryman. Technology transfer - Its contribution to the Canadian nuclear industry. I_n Experience in Transfer of Nuclear Technology. Proceedings of the Iran Conference on Transfer of Nuclear Technology, Persepolis/Shiraz, Iran, April 1977, p.2. Atomic Energy of Canada Limited, reprint AECL-6132 (1978). ATOMIC ENERGY OF CANADA LIMITED

AECL AECL AECL AECL AEC RESEARCH RADIOCHEMICAL CHEMICAL ENGINEERING INTERNATIONAL COMPANY COMPANY COMPANY COMPANY

I

FIGURE 1 THE FIVE OPERATING UNITS OF AECL FIGURE 2 CHALK RIVER NUCLEAR LABORATORIES FIGURE 3 WHITESHELL NUCLEAR RESEARCH ESTABLISHMENT - 39 -

• Whlteshell Nuclear Research Establishment

Chalk River Nuclear Laboratories

FIGURE 4 AECL RESEARCH COMPANY SITES - 40 -

STAFF

SITE PROFESSIONAL TECHNICAL ADMINISTRATIVE TRADES TOTAL

HEAD OFFICE 20 20 40 CRNL 450 510 370 890 2220 WNRE 220 240 170 220 850

TOTAL 690 750 560 1110 3110

FUNDING (MILLIONS OF DOLLARS)

CANADA COMMERCIAL TOTAL

OPERATING 110 20 130 CAPITAL 10 10

TOTAL 120 20 140

FIGURE 5 AECL RESEARCH COMPANY: STAFF AND FUNDING 1979/80 2000

1000

10 • 1955 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 FISCAL YEAR

FIGURE 6 ANNUAL GOVERNMENT EXPENDITURES ON CIVIL NUCLEAR PROGRAMS — CURRENT PRICES IN MILLIONS U.S. DOLLARS - 42 -

eg OJ

4 INCH EXPERIMENTAL LEAD ' HOLE DOOR 12 INCH EXPERIMENTAL HOLE

OUTLET WATER & MAIN

-MOUTH-SOUTH ELEVATION- • EAST - WEST ELEVATION —

FIGURE 7 ELEVATION CROSS SECTION OF THE NRX REACTOR TANGENTIAL HOLE 12 INCH EXPERIMENTAL SELF-SERVE HOLE HOLE

(5.5 m)

4 INCH EXPERIMENTAL HOLE

ION CHAMBER HOLE

(5.5 m)

SOUTH '/{• THERMAL ir fV-, COLUMN ]•'•

FIGURE 8 PLAM CROSS SECTION THROUGH THE NRX REACTOR STRUCTURE - 44 -

< x o < Hi cc X cr z

g u. I— 39'-0"(11-9m)

• EXPERIMENTAL HOLES J-RODS GATE STEELTHERMALSHIELD ^ EIGHT DgO PIPES TO HEAT EXCHANGERS LIGHT WATER AND PUMPS

CALANDRIATHROUGHTUBE

SHUTTER H2O REFLECTOR

LEAD DOOR SERVICE SHAFT

BORAL CADMIUM LINING D2O I

THERMAL COLUMN " " D2O REFLECTOR

GRAPHITE — CALANDRIAWALL

BISMUTH RODS

ALUMINUM WINDOW

- CONCRETE SHIELD FUEL RODS

THERMAL COLUMN EXPERIMENTAL HOLES ! METRES SCALE— 0 I 2 FEET

FIGURE 10a PLAN CROSS SECTION OF THE NRU REACTOR 30'-0" (9.15 m)

. DECK PLATE.

SERVICE SPACE J-RODTUBE PERMANENT ROD TUBES -- (TOTAL OF 218) CONCRETE BULK LIGHT WATER — • SHIELDING

BOILER SECTIONS CALANDRIA E TUBE SHEET AND HEAT BAFFLE EXPERIMENTAL HOLE RE-ENTRANT CANS STEEL THERMAL SHIELD GATES

-» 4 - J-RODANNULUS FLOW TO EIGHT HEAT EXCHANGERS

EXPERIMENTAL HOLES

HEAT BAFFLE AND ROD SOCKETS

MAIN FLOOR

Is.. BOTTOM HEADER

1 STEEL AND LIGHT HEAT V WATER SHIELDS EXCHANGER

SERVICE SPACE

FIGURE 10b ELEVATION CROSS SECTION OF THE NRU REACTOR - 47 -

FIGURE 11 NRU FUELLING MACHINE FUELLING MACHINE 00 I

HEAVY WATER DUMP TANK

FIGURE 12 CUTAWAY DRAWING OF THE NPD REACTOR VESSEL AND ADJACENT EQUIPMENT HEAVY WATER COOLANT

HEAVY WATER MODERATOR

I | HELIUM

ORDINARY WATER

RIVER WATER

MODERATOR DUMP TANK

MODERATOR

FIGURE 13 NPD SCHEMATIC FLOW SHEET - 50 -

CUMULATIVE ELECTRICAL CAPACITY OF CANDU REACTORS

ZUUUU

19000

TOTAL 18353 MW|e) - - fc 18000 - Darlington ?•

17000 - I)ariingion 3

Darl Ington 2 16000 _

Darling ton 1 15000 _ _ . I Cernavod82 Romania > 14000 - ) Cerne-Ha 1 -

brace 8 13000 - - Bruce 7

12000 Pickering el s. Bruce 6 11000 - - •J> Pickering 7 a. < 10000 - Pickering 6 Gentilly 2 o 9000 - Argentina: Cordoba - EC Wolsung 8UO0 _ _ .kC I XI Bruce 5 7000 - Pickering 5[ - Point Lepreau 6000 - RAPP 2 •''] Bruce 4 f 5000 _ - Bruce 3p 4

4000 Pickering 4 x Bruce If -

Pickering 3-A . Bruce 2["V5> 3000 RAPP lA \ II • rf- (!• y'^ KANUPPO\\ 2000 - Pickering 2OO> MDER Gentilly 1 A> OPERATING **„ CONSTRUCTION 1000 - Pickering lOv Douglas Point *f II NPD llJ 1965 1970 1975 1960 1965 1990 1995 YEAR OF START-UP

FIGURE 14 CUMULATIVE ELECTRICAL CAPACITY OF CANDU REACTORS GENEALOGY OF CANDU REACTORS

too DARLINGTON

MW(th)

1945 1950 1955 1960 1965 1970 1975 1980 1985 1990 YEARS

FIGURE 15 GENEALOGY OF CANDU REACTORS STEAM TO TURBINE^ STEAM TO TURBINE STEAM TO TURBINE STEAM DRUMJ REACTOR PRESSURE STEAM STEAM/WATER MIXTURE TUBES GENERATOR FUEL FUEL FUEL

HEAVY WATER COOLANT

HEAVY WATER MODERATOR HEAVY WATER WATER FROM HEAVY WATER PUMP WATER FROM MODERATOR CONDENSER MODERATOR M CONDENSER WATER FROM I PHW CONDENSER BLW OCR (Pressurized Heavy Water) (Boiling Light Water) (Organic Cooled Reactor)

FIGURE 16 ALTERNATIVE CANDU REACTOR DESIGN CONCEPTS USING DIFFERENT - 53 -

FIGURE 17 CUTAWAY DRAWING OF THE SLOWPOKE REACTOR 200

PROMPT PEAK 9.0 FAST PEAK

8.0

7.0 REACTOR POWER

6.0 § 5.0 100 a o o 4.0 SLOWPOKE - 1 POWER EXCURSION (Tola! withdrawal of »b»orb»r at Time

3.0

2.0

1.0

50

10 20 30 40 TIME.s

FIGURE 18 SLOWPOKE POWER EXCURSION TRANSIENT FIGURE 19 FUELLING MACHINE DEVELOPMENT AT SHERIDAN PARK ENGINEERING LABORATORIES TOTAL

MANPOWER

1000 PROFESSIONAL

0 1950 1960 1970 1980 YEAR MANPOWER IN RESEARCH AND DEVELOPMENT ATAECL - 57 -

CRNL WNBE RESEARCH COMPANY 62% 38 %

COMPRISING:

ENVIRONMENT UNDERLYING 29% WASTE 24% RESEARCH MANAGEMENT

—*

POWER ADVANCED REACTOR 33% FUEL 9% SYSTEMS CYCLE

HEAVY ASSESSMENTS WATER 4% NEW 1% PROCESSES APPLICATIONS

FIGURE 21 DISTRIBUTION OF PROFESSIONAL MAN-YEARS: RESEARCH AND DEVELOPMENT PROGRAM FIGURE 22 PERCH LAKE WITH CRNL IN THE BACKGROUND TURTLES 10

CARNIVORES ADULT PERCH 18

FROGS 30

SUNFISH 80

HERBIVORES TADPOLES 250 SNAILS 4400

PLANTS AQUATIC PLANTS 20-2800

U1

SEDIMENT 200

FIGURE 23 SOME MAJOR PATHWAYS OF COBALT-60 IN THE PERCH LAKE ECOSYSTEM SHOWING RELATIVE CONCENTRATIONS FOCUSSING MAGNET ANALYZING MAGNET SWITCHING MAGNET

CONTROL ROOM \ \ | TARGET ROOM NO 1 MP TANDEM VAN DE GRAAFF ACCELERATOR

ACCELERATOR TANK

NEGATIVE ION SOURCE

DIAGRAMMATIC VIEW souece of HIGH NEGATIVELY CHARGED •13 MILLION VOLT POSITIVE TERMINAL

BEAM OF NEGATIVE PARTICLES ATTRACTED AND ACCELERATED TO HIGH VOLTAGE POSITIVE

^E CHARGE CHANGED TARGET FROW NEGATIVE 1O POSITIVE ACCELERATED P A P 1«C L F:

FIGURE 24 20 MeV MP TANDEM ACCELERATOR AT CRNL SPALLATION FACILITY

HIGH ENERGY SOURCE ALVAREZ TANKS STRUCTURE

COCKCROFT-WALTON AND COLUMN C. W. LINEAR ACCELERATOR THORIUM BLANKET

Pb/Bi TARGET

PROTON SPALLATION REACTION

O NEUTRON

1 PROTON AT 1GeV ON Bi THICK TARGET PRODUCES 30n AND 3GeV HEAT CASCADE

FIGURE 25 PRINCIPLE OF THE ACCELERATOR BREEDER MODULATOR AND FILAMENT SUPPLIES

QUADRIFILAR PULSE TRANSFORMER

ANNULAR ELECTRON GUN 1 TARGE!GET MAGNET 33 CELL 1.6m CURRENT LINAC CURRENT MONITOR CURRENT MONITOR MONITOR FIRST PASS SWEEPING 30//S ION MAGNET FARADAY CUP PUMP STEERING MAGNET

FULLY STOPPING TARGET OR THIN FOIL

DOUBLE PASS FARADAY CUP

FIGURE 26 SCHEMATIC LAYOUT OF THE MEDICAL LINEAR ACCELERATOR BELLEVILLE

GAP

SECONDARY PACKING

LEAK OFF

PRIMARY PACKING

TYPICAL 25.4 mm GLOBE VALVE TYPICAL 25.4 mm GLOBE VALVE WITH CONVENTIONAL PACKING WITH LIVE-LOADED PACKING

FIGURE 27 LIVE-LOADED VALVE PACKING ARRANGEMENT - 64 -

WiTH LIVE- AS INSTALLED LOAOING ADDED

RELATIVE REPACKING FREQUENCY 108 1 RELATIVE RETORQUING FREQUENCY 1140 1 RELATIVE MAINTENANCE TIME 150 1 RELATIVE MAINTENANCE EXPOSURE 180 1 MAINTENANCE COSTS, MS/a 1 0.002

FIGURE 28 BENEFITS OF LIVE-LOADING IN CONTROL VALVES AT THE PICKERING GENERATING STATION SI fi»MJ/»hv Ml AV rvn' CMlVAWV SI f AV ( v( i DM

[ A[J| M

FIGURE 29 600 MW STEAM GENERATOR VELOCITY PLOTS STEAM QUALITY CONTOURS

COLO SIDE HOT SIDE COLD SIDE HOT SIDE

U-BENO REGION U-BEND REGION

. <. • • 11'. • , . I I 111 11 • . . . i I • M I '

..'•'•II MIDPOINT MIDPOINT I i " t I

111;!- ':': •' I PREMEATER EXIT PREHEATER EXIT

TUBESHEET TUBESHEET

FIGURE 30 THIRST COOE STEAM GENERATOR ANALYSIS TUBE SELECTOR MECANISM

FIGURE 31 CANSCAN EDDY CURRENT INSPECTION SYSTEM FOR BOILER TUB!' - t> a -

FIGURE 32 TUBE SHEET WALKER CARRYING PROBES AND CABLES - 69 -

BRUCE A" 4 x 740 MW(e)

PICKERING A 4 x 515 MW(e)

8 DOUGLAS POINT - 206 MW(e)

« 6 - 5 1

-LJ 4 tr | I ll 2

0 .ill Hllll..

12 NPD 22 MW(e)

10

to 8 5 1 6 tr

196.lll2 63 64 65 l66 67 68 69 70 71 72 73 74 75 76 77 78 79

FIGURE 33 TOTAL ANNUAL EXTERNAL DOSE TO OPERATING STAFF AT CANDU NUCLEAR GENERATING STATIONS FIGURE 34 SIMPLIFIED FLOW SHEET OF THE U-1 LOOP - 71 -

FIGURE 35 METALLOGRAPHIC EXAMINATION OF A CROSS SECTION OF AN IRRADiATED URANIUM DIOXIDE FUEL ELEMENT AT CRNL I

FIGURE 36 OPERATOR USING REMOTE MANIPULATORS TO HANDLE HIGHLY RADIOACTIVE MATERIAL IN SHIELDED CELLS AT WNRE FIGURE 37 FULL-SCALE HORIZONTAL PRESSURIZED WATER CRITICAL HEAT FLUX FACILITY - 74 -

FIGURE 38 ELECTRICALLY HEATED SIMULATED STRING OF FUEL BUNDLES FOR CRITICAL HEAT FLUX TEST - 75 -

FIGURE 39 PRESSURIZED WATER LOOP IN THE CANDU FIGURE-OF-EIGHT CONFIGURATION FOR LOSS OF COOLANT EXPERIMENTS FIGURE 40 PORT HAWKESBURY HEAVY WATER PLANT - 77 -

PLAN VIEW

TWO-PASS TRAYS

FIGURE 41 SCHEMATIC OF TWO-PASS SIEVE TRAY 80

70

60

25% 5% WEEPAGE ENTRAPMENT 50

UJ O 40

CL

30 00

I PREDICTED ErFICIF.NCY OF TYPICAL TWO-PASS HOT TCWER TRAY 20

10

PERCENT OF DESIGN FLOW 70 80 90 100 110 120 I I I I I 1.5 2.0 2.5 3.0 3.5

F-FACTOR(kg"2.s'.m' 2)

FIGURE 42 EFFECT OF GAS VELOCITY ON HOT TOWER TRAY EFFICIENCY FOR THE WATER HYDROGEN-SULPHIDE PROCESS NONCOMBUSTIBLE COMBUSTIBLE SPENT WASTE SOLID AND LIQUID WASTE ION EXCHANGE RESIN AQUEOUS WASTE 1 i ULTRAFILTRATION • WATER TO REVERSE OSMOSIS DISCHARGE r OR RECYCLE /

EVAPORATOR

WIPED FILM BITUMIN'.ZER

I

STORAGE

FIGURE 43 SCHEMATIC FLOWSHEET FOR THE CHALK RIVER WASTE TREATMENT CENTRE FIGURE 44 FUEL STORAGE BAY AT THE BRUCE GENERATING STATION - 81 -

REINFORCED j CONCRETE UPPER l-UEL BASKET

VlLD STEEL IRRADIATED STORAGE CAN FUEL BUNDLES

LOWER FUEL BASKET

FIGURE 45 SCHEMATIC OF A WNRE CANNISTER FOR DRY STORAGE OF FUEL - 82 -

CANDU REACTORS

IRRADIATED

IRRADIATfcD F STORAGF

MATERIALS STORAGE

IRRADIATED FUEL

USEFUL MATERIALS

UNSEPAHATEO U'Pu

SEPARATION

WASTE

WASTE IMMOBILIZATION FUEL IMMOBILIZATION

IMMOBILIZED WASTE IMMOBILIZED FUEL

DISPOSAL

FIGURE 46 OPTIONS FOR CLOSING THE NATURAL URANIUM FUEL CYCLE - 83 -

'"Sr CONCENTRATION 1m DOWNSTREAM OF GLASS BLOCKS BURIED AT CRNL IN 1960 (25 GLASS BLOCKS CONTAINED 1100 Ci OF AGED FISSION PRODUCTS WHEN BURIED)

1960 61 62 63 64 65 66 67 68 69 70 71 73 74

FIGURE 47 LEACHING OF STRONTIUM-90 FROM NEPHELINE SYENITI GLASS BURIED AT CRNL. - 84 -

FIGURE 48 WASTE DISPOSAL FACILITY - 85 -

RESEARCH COMPANY CRNL WNRE 60% 40%.

COMPRISING:

FUEL 36% REACTOR 29% DEVELOPMENT PHYSICS

SEPARATIONS 19% TECHNOLOGY ASSESSMENTS 14%

FIGURE 49 DISTRIBUTION OF PROFESSIONAL MAN-YEARS: ADVANCED FUEL CYCLE PROGRAMS I

CO

FIGURE 50 THE RECYCLE FUEL FABRICATION LABORATORY AT CRNL ISSN 0067 - 0367 ISSN 0067 - 0367

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1783-80