The development of the first candu reactor began in 1954 through a partnership between atomic energy of canada ltd. Each fuel channel contains 12 or small fuel bundles, each of which is 50 cm long and 10 cm in diameter, and weighs about 24 kg. These reactors are heavy water cooled and moderated pressurized water reactors. Nuclear reactor, any of a class of devices that can initiate and control a selfsustaining series of nuclear fission s. Introduction this is a descriptive course on the physics of candu reactors. Kuran vp, advanced fuel candu reactor workshop on advanced reactors, neaoecd paris, france, april 2017. Risks of the candu reactor design introduction the candu canada deuterium uranium reactor is a pressurized heavy water reactor of canadian design.
It combines features of the existing candu pressurised heavy water reactors phwr with features of lightwater cooled pressurized water reactors pwr. In preceding chapters nuclear chain reaction, the classification of states of a reactor according to the effective multiplication factor k eff was introduced. All structured data from the file and property namespaces is available under the creative commons cc0 license. The soviets developed it, by themselves, from early models which had been first used to generate plutonium for weapons, and to produce heat for district heating. Reactor assembly the candu 6 reactor assembly, shown in the figure opposite, includes the fuel channels contained in and supported by a horizontal cylindrical tank known as the calandria. Candu reactors have two independent shutdown systems that can be actuated by the incore reactor protection system and that are able to effect a rapid reactor shutdown. The candu reactor has a modular core, made up of fuel channels. Zircaloy 2 and ni free zircaloy 2 recent manufacture. Overview of candu pressurized heavy water reactor phwr. Pg 2 codes and standards requirements for candu design.
Candu reactor the candu short for canada deuterium uranium reactor is a canadiandeveloped, pressurized heavy water reactor used for generating electric power. The directions and technical development of the candu reactor are. Most countries can manufacture the relatively inexpensive fuel. Introduction to reactor physics candu owners group. Use of natural uranium widens the source of supply and makes fuel fabrication easier. Modular horizontal fuel channel fuel bundle design low temperature, low pressure heavy water moderator onpower fueling passive shutdown systems in low pressure moderator. The mean flight path length of a neutron between collisions the mean free path gives an. Candu energy says its new nuclear technology, which is able to use spent fuel from other reactors, has cleared a hurdle in china. Heavy water cooled and moderated the only design of heavy water moderated reactor in commercial use is the candu, designed in canada and subsequently exported to several countries. The candu, for canada deuterium uranium, is a canadiandeveloped, pressurized heavy water reactor used to generate electric power. Issued by a government body, the standards council of canada.
The advanced fuel candu reactor afcr is a generation iii advanced fuelefficient 740 mweclass pressurized heavy water reactor developed by candu energy, a member of the snclavalin group and china national nuclear corporation. The candu reactor uses either light or heavy water for its coolant. The calandria tubes are made of nickel free zircaloy2 and are attached to the. Nuclear power nuclear power plant types of reactors candu heavy water reactor. The second method is atomic deuterium, generated by corrosion, entering the pressure tube through the martensitic 403 stainless steel end fitting. A free powerpoint ppt presentation displayed as a flash slide show on id. The fuelling operations for these stations begin with the semimanual loading of new fuel. Molten salt reactors the next generation of nuclear power duration.
Vault candu nuclear power plant schematic the condenser turns the steam back into water which is then returned to the steam generators through the feedwater system. Chapter 1 introduction to nuclear reactors pdf 700kb by dr. Regulatory policies, standards, guides developed and applied by canadian nuclear safety commission formerly aecb canadian codes and standards. Based on over 60 years of proven operational excellence of the candu reactor fleet and experience. Overview ofnegative pressure containment output700 mwe, operate at 10 mpa, 312 c outlet header, may be 24% reactor outletheader quality in service dates. Files are available under licenses specified on their description page. Subscribers can get the latest information on specific topic areas for selected candu and industry activities. The acronym refers tae its deuterium oxide hivy watter moderator and its use o originally, natural uranium fuel. This manual also lists the corrective actions to be taken. The design and development of fuel for the candu type reactors have been. Candu reactors were first developed in the late 1950s and 1960s by a partnership between atomic energy of canada limited aecl. The candu reactor design or phwr pressurized heavy water reactor has been developed since the 1950s in canada, and more recently also in india. Chernobyl a canadian perspective candu owners group. The heavy water coolant is pumped through the reactor cores tubes in a closed loop.
From reactors that burn lowenriched fuel, with some pretreatment, yes. Advanced candu reactor acr700 builds on candu 6 design, project and operational experience retained traditional candu features. Nuclear reactors are used as research tools, as systems for producing radioactive isotope s, and most prominently as energy sources for nuclear power plants. Check the cogonline calendar or the downloadable at a glance pdf on cogonline under events to get involved. In normal candu operations with natural uranium fuel, more than half of the energy is provided by fissioning plutonium produced in the fuel as the reactor operates. The effective multiplication factor k eff is a measure of the change in the fission neutron population from one neutron.
The essential candu a textbook on the candu nuclear power plant technology. The results indicated that the dry storage costs for the candu system were. Candu reactor is a type of nuclear reactor which was developed in canada, and is currently used in nuclear power plants for electrical generation in various countries around the world. Pdf performance of pressure tubes in candu reactors. State why reactor power first drops rapidly following a large negative reactivity insertion and then continues to decrease more slowly. The calandria is closed and supported by end shields at each end. Schematic diagram of the pressurised heavy water cooled version of a candu canada deuteriumuranium nuclear reactor. For a reactor at low power, compare the change in reactor power following a very small positive reactivity insertion with a much larger insertion but one that is too small to cause prompt criticality.
The candu, for canada deuterium uranium, is a canadian pressurized heavywater reactor design used tae generate electric pouer. A pressurised heavy water reactor is a nuclear power reactor that uses unenriched natural uranium as nuclear fuel and heavy. Dry storage costs for spent fuel from a candu reactor design have been compared to those for a typical pressurized light water reactor both normalized to a gross power of mwe 3. The essential candu is brought to you by unene with administrative and sponsorship support from cog. Probably that preretreatment is more expensive than new regular candu fuel. Candu reactors are currently operated by several canadian and foreign utilities. The pressurized heavy water phw cooled version was the first type to be developed and is by far the most widely used.
This candu textbook is suitable for students, educators, trainers and working professionals at a target level of senior undergraduate year university engineering and science. Candu fuel cycle advantages operational reactors nue candu reactor inherent safety features new build reactors afcr future with water coolant dr. Candu fundamentals i table of contents 1 objectives 1 1. All canadian nuclear reactors are of the candu type but the. The first is from aqueous corrosion of the inside surface of the main body of the pressure tube.
The calandria is filled with non pressurized heavy water acting as moderator. Shutdown system number one sds1 consists of cadmium absorbers. During reactor operation, pressure tube material is subject to high pressure up to 11. Under candu reactor operating conditions, pressure tubes absorb deuterium through 2 main sources. Candu reactors were first developed in the late 1950s an 1960s bi a partnership between atomic energy of canada limited aecl, the. Candu stands for canada deuterium uranium, which reflects the key role of deuterium, or heavy water, which acts as the reactors neutron moderator, a unique trait of the candu. The candu 6 design as implemented at sites in canada has been chosen as the reference because it is the most widely deployed candu design worldwide. The acronym refers to its deuterium oxide heavy water moderator and its use of originally, natural uranium fuel. Characteristics of acr700 and candu 6 coreaveraged 20. Each end shield comprises an inner and an outer tubesheet joined by lattice tubes at. The objective is to familiarize you with the basic concepts and ideas, definitions and quantities which are important in the understanding of reactor physics. The mean flight path length of a neutron between collisions the mean free path gives an indication of the degree of inhomogeneity of any reactor assembly consisting of fuel elements. The company said thursday that a chinese expert panel has given a. Canducanada deutrium uranium it is a canadianinvented,heavy water reactor.
As a result, adding plutonium to the initial fuel would represent a smaller change in the physics of. Rouben mcmaster university nuclear reactor analysis ep 4d036d03 2012 janapr 2012 september outline a quick look at the. Atomic energy of canada limited aecl developed the candu reactor technology starting in the 1950s. From candu, it takes the heavy water moderator, which gives the design an. This reflector also has an important effect on reactor dynamics because of its very long diffusion length. The 20,000 peoples lifetime leftover bwr fuel seen here will not work until those very tough c. Written by canadian standards association csa local codes and standards, as agreed by. Inspection of candu reactor pressure tubes using ultrasonics. Intro to materials scienceguided inquiry uva 21,999 views.
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