India designs worlds first thorium based nuclear reactor. Pdf gascooled thorium reactor with fuel block of the. An abundant metal with vast energy potential could quickly wean the world off oil, if only western political leaders would muster the will to do it, a uk newspaper says today. Thoriumfueled reactors, on the other hand, are fuelefficient, almost perfectly so, but that comes at the end of a threephase process, with the first phase shared by thorium and uranium fuel.
Thorium reactors are the latest big thing in nuclear spin. Heres a post i wrote for a coursera course i was taing. Some reactors are designed to run on alternative thorium fuel cycle, which offers significantly reduced longterm waste radiotoxicity compared to uranium cycle. Molten salt reactors msrs papers, books, and reports. Although thorium reactors have a high initial startup cost, those costs can be reduced with proper manufacturing techniques. The liquidfluoride thorium reactor lftr design by flibe energy is a graphitemoderated, thermalspectrum reactor with solutions of liquid fluoride salts containing both fissile and fertile materials.
Introduction of thorium in the nuclear fuel cycle nuclear science 2015 232 90 nea short to longterm considerations introduction of thorium in the nuclear fuel cycle. Andrew yang loves thorium nuclear reactors, but what are they. Flibe energy is a usbased company established to design, construct and operate small modular reactors based on liquid fluoride thorium reactor lftr technology a type of molten salt reactor. On the cover left to right are the molten salt reactor during core assembly a magnified view of. Their waste burner design, for example, is small enough that it can fit inside a standard shipping container. Main purpose of the nuclear reactor is to initiate and control a sustained nuclear chain reaction. C, and this liquid serves as both heat transfer fluid and. Vijayan reactor engineering division, bhabha atomic research centre, trombay, mumbai400085,india email of corresponding author. Reactors that use thorium are operating on whats called the thoriumuranium thu fuel cycle. Current development in thorium fueled reactors shows that they can be designed to operate in the fast or thermal spectrum. Dr john harries is a physicist with extensive experience on the physics of nuclear. Additionally, there is the persistent perception that thorium reactors are intrinsically proliferationresistant.
The name flibe comes from flibe, a fluoride salt of lithium and beryllium, used in lftrs. It is the latest indian design for a nextgeneration nuclear reactor that will burn thorium as its fuel ore. Second, as we pointed out last year in a long read on thoriumsalt reactors, designs that call for using it in a liquid form are, essentially, selfregulating and failsafe. In the reactor, 232 th is transmuted into the fissile artificial uranium isotope 233 u which is the nuclear fuel.
It is fueled by the uranium233 isotope that is taken from the element thorium. Thoriumbased nuclear power generation is fueled primarily by the nuclear fission of the isotope uranium233 produced from the fertile element thorium. Nuclear power will be used continuously as lowcarbon energy for a sustainable society. Interest in liquidfluoride reactors with dissolved nuclear fuel is also present at the industrial level with the formation of flibe energy in 2011. Worldwide, 1 smr units are in operation in 26 member states, with a capacity of 59 gwe. Thats because the united states, india, japan, and russia pdf are among the countries now working on thorium reactors. Thorium salt reactor experiments resume after 40 years. One of the biggest challenges in developing a thorium reactor is finding a way. Thorium reactors are according to the proponents of this technique so also much safer than current reactors. These reactors are still at the design stage but are likely to be very well suited for using thorium as a fuel. Small modular reactors smrs are a type of nuclear fission reactor which are smaller than conventional reactors.
Pdf the case for the thorium molten salt reactor researchgate. The initial enthusiasm on thorium fuels and fuel cycles was not sustained among the developing countries later, due to new discovery of uranium deposits and their improved availability. By utilizing thorium fuel in a thermal neutron spectrum, the reactor is able to utilize the energy. This molten salt is also used as a refrigerant and as fuel. Is thorium the fuel of the future to revitalize nuclear. October 8, 2018, marks the fiftieth anniversary of the operation of the moltensalt reactor experiment msre using uranium233 as a fuel.
Copenhagen atomics believes that thorium reactors could be produced on an assembly line. There are no thorium reactors running today, but flibe energy inc. Most common nuclear reactors are light water reactors lwr, that are based on the uranium fuel cycle and use an enriched uranium fuel 4% of u235 as a. A comprehensive study from the us energy department in 2014 found that waste from thoriumuranium fuel cycles has similar radioactivity at 100 years to uraniumplutonium fuel cycles, and actually has higher waste radioactivity at 100,000 years.
Flibe energy is pursuing a design called a liquidfluoride thorium reactor lftr, which is a modern variant of the work initiated at oak ridge during their research into moltensalt reactors. Thorium power has a protactinium problem bulletin of the. Criteria for the reactor safety systems of research reactors 15. Thorium energy conference 2015 thec15 october 1922, 2015, mumbai, india conceptual design of loopintank type indian molten salt breeder reactor concept abhishek basak, i.
Thorium fuel cycle is an attractive way to produce long term nuclear energy with low radiotoxicity waste. Some of the points may be slightly debatable or not applicable to all msrlftr designs, but i hope it paints a clear picture as to the difficulty in msrs. Thorium nuclear reactors quite a bad idea really exposing. The waste from thorium reactors would be easier to deal with than waste from todays uranium reactors. If thorium lftr reactors are so awesome, why hasnt. Conceptual design of thorium based epithermal spectrum. In general, a nuclear reactor is a key device of nuclear power plants, nuclear research facilities or nuclear propelled ships. Whats the difference between thorium and uranium nuclear. That much thorium can be found in about any cubic meter of rock on earth, moon or mars.
Mining of rare earths typically yields abundant thorium as a byproduct a free fuel. Most thorium fueled designs are breeder reactors, meaning they produce more fissile material than they consume. The tpc thorium reactor can be built on a modular basis as small as 10mw in size with the option to upscale a facility to 100mw by linking the modular reactors together. Thorium fueled reactors, on the other hand, are fuelefficient, almost perfectly so, but that comes at the end of a threephase process, with the first phase shared by thorium and uranium fuel. It is found that thorium fuel can be utilized in molten salt reactors through many configurations and designs. Nuclear power corporation of india the kalpakkam fast breeder reactor, near tamil nadu. The design of worlds first thorium based nuclear reactor is ready. Fire protection program criteria for research reactors. India today online brings you the first look of design and prototype of the advanced heavy water reactor, also termed as ahwr. Thorium fuel cycle potential benefits and challenges. Worldwide, 1 smr units are in operation in 26 member states, with a.
Gascooled thorium reactor with fuel block of the unified design article pdf available in advances in materials science and engineering 20151 august 2015 with 173 reads how we measure reads. In addition, thorium reactors have an inherently safe design that shuts down if the reaction goes out of control, and the radioactive waste products from thorium are relatively short lived. Modular reactors allow for less onsite construction, increased containment efficiency, and enhanced safety due to passive safety features. A convenient way to differentiate between them is by core type. No enrichmentenergy wasted 232 th is just a metal common in rareearth ores.
And here is one place the thorium uranium fuel cycle differs from the uraniumplutonium fuel cycle. So proven designs for thoriumbased reactors exist and need but for some support. The best way to explain the design choices behind the ca waste burner is to understand what it would take to power more than twothirds of the entire global population with energy at 200 gj per capita per year. According to their enthusiastic proponents, these reactors will be smaller, safer, cheaper, cleaner, will take over the energy market in great numbers, and. But does thorium really represent nuclear innovation. Thermal power generated from nuclear fission would drive electrical generation in a closedcycle gas turbine power conversion system.
Unlike natural uranium, natural thorium contains only trace amounts of fissile material such as 231 th, which are insufficient to initiate a nuclear chain reaction. Andrew yang, an entrepreneur and democratic candidate for the 2020 presidential election, promises to make thorium molten salt reactors as part of his climate plan for achieving netzero emissions by 2050. Doe has a 3200ton stockpile enough for years of all us energy needs without mining. This allows them to be manufactured at a plant and brought to a site to be assembled. Reactors that use thorium are operating on whats called the thorium uranium thu fuel cycle.
Design of the fuel elements for the hightemperature gascooled. Sep 12, 2019 plus, used fuel from thorium reactors contains minimal amounts of very longlived radioactive materials compared to current uranium fuel, so disposing of waste is easier. Pedersen, in molten salt reactors and thorium energy, 2017. Reactor vhtr, msrmolten salt reactor, or lftr liquid fluoride thorium reactor refer. A thorium reactor is a form of nuclear energy, proposed for use as a molten salt reactor. U233 is a superior nuclear fuel, producing enough neutrons through its fission.
Feb 16, 2012 so proven designs for thorium based reactors exist and need but for some support. General design description design philosophy the objective of the liquidfluoride thorium reactor lftr design proposed by flibe energy is to develop a nuclear power plant that will produce electrical energy at low cost. In addition, the transition to thorium could be done through the. To a limited group of technophiles and nuclear technology enthusiasts, thorium has become a unicorn. Thorium reactors are the latest flavour in nuclear power hype. The unique fluid fuel can incorporate thorium and uranium u233 andor u235 fluorides as part of a salt mixture that melts in the range 400700. The vast majority of existing or proposed nuclear reactors, however, use enriched uranium u235 or reprocessed plutonium pu239 as fuel in the uraniumplutonium cycle, and only a handful have used thorium. Since the fuel salt is liquid, it can be both the fuel producing the heat and the coolant transporting the heat to the power plant. The most likely nearterm application of thorium in the united states is in currently operating light water reactors lwrs. Molten salt reactors offer potential improvements in reactor safety. A thoriumsalt reactor has fired up for the first time in. Safety and regulatory issues of the thorium fuel cycle.
Some of the following points can be valid for one reactor design and another point can be invalid for another thoriumbased reactor. All thorium is consumed no spent fuel 90% of bwrpwr uranium is unused. High efficiency nuclear power plants using liquid fluoride thorium. Important thorium reactor configurations include molten salt, candu, and triso. Thorium based nuclear power generation is fueled primarily by the nuclear fission of the isotope uranium233 produced from the fertile element thorium. According to proponents, a thorium fuel cycle offers several potential advantages over a uranium fuel cycleincluding much greater abundance of thorium on earth, superior physical and nuclear fuel properties, and reduced nuclear waste production. And the breeding capability of thorium is confirmed by providing caption to fission reaction rate. Advantage and disadvantages of thorium reactors pros and cons.
Most thoriumfueled designs are breeder reactors, meaning they produce more fissile material than they consume. Back in the 1950s and 1960s, the scientists at oak ridge national laboratory in the usa developed the molten salt reactor design a liquid salt fueled and cooled nuclear reactor system. It is very difficult to explain the possible advantages and disadvantages. It is the latest indian design for a nextgeneration. Into this dynamic comes a resurgence in nuclear technology. The thoriumuranium fuel cycle converts fertile thorium232 into fissile. In particular conceptual designs for an advanced 1 gwe power plant with turbine reheat and. Thorium fuel cycle iaea scientific and technical publications. Design objectives for and monitoring of systems controlling research reactor effluents 15. Smrs have been proposed as a way to bypass financial and. On the other hand, prime attention is inclined to thorium moltensalt reactor msr in recent years due to necessity for radioactive waste disposal, nuclear.
Aug 06, 2018 molten salt reactors offer potential improvements in reactor safety. Molten salt reactors msrs are nuclear reactors that use a fluid fuel in the form of very hot fluoride or chloride salt rather than the solid fuel used in most reactors. Abundant thorium as an alternative nuclear fuel mit. The thorium uranium fuel cycle converts fertile thorium 232 into fissile. Jan 14, 2015 thorium reactors are according to the proponents of this technique so also much safer than current reactors. Thorium is a relatively abundant, slightly radioactive element that at one time looked like the future of nuclear power. For example, in a liquid fluoride thorium reactor lftr the fuel is not processed as a solid but is dissolved in a molten fluoride salt. The head of the mumbai reactor design and development group, ratan kumar sinha, spoke to ieee spectrums seema singh in july about the challenges of and prospects for this new thorium reactor. If thorium lftr reactors are so awesome, why hasnt anyone. Employing molten salt in place of water to transfer heat from the fuel allows a reactor to operate at a higher temperature and at lower pressure, which means it doesnt. The name flibe comes from flibe, a f luoride salt of li thium and be ryllium, used in lftrs.
Therefore, be careful when you argue for or against thorium reactors. When hit with a neutron, 232th transforms into 233th, then goes. A lftr is a type of molten salt reactor, significantly safer than a typical. Second, as we pointed out last year in a long read on thorium salt reactors, designs that call for using it in a liquid form are, essentially, selfregulating and failsafe. It is concluded that the epithermal spectrum reactor may be possible to design by changing design parameters from the conventional reactors and it make it provide enhanced breeding capability when combined with thorium fuel. Ix latin american symposium on nuclear physics and applications. Development of tiny thorium reactors could wean the world. This talk will examine the history of thorium reactors. Introduction of thorium in the nuclear fuel cycle nuclear energy. Thorium is weakly radioactive, has a high melting point, and is available with more abundance than uranium as an element. And here is one place the thoriumuranium fuel cycle differs from the uraniumplutonium fuel cycle. The thorium fuel cycle is a nuclear fuel cycle that uses an isotope of thorium, 232 th, as the fertile material. Advantage and disadvantages of thorium reactors pros and.