Modular high temperature gas cooled reactor safety design. Project hfreu1 this is a new conductioncooled design with double containment for up to. In principle all of these consist of a graphite moderated. They are often the highest temperature point in the process, heat of reaction may be released, and residence times can be long leading to a large inventory of chemicals. The design of a chemical reactor deals with multiple aspects of chemical engineering. High temperature reactors an overview sciencedirect topics. The mhtgr design approach leading to exceptional safety performance also leads to plant operation which is characterized by extremely low radiological emissions even for very low probability accidents. Creep is a time dependent property, which determines the deformation in a given time and at a given temperature by a refractory material under stress. The high graphite inventory provides significant thermal inertia.
Hydrogen production using high temperature reactors techno press. The last reactor to come into service was the tennessee valley authoritys tva watts bar 1 in 1996. Consider an exothermic reaction where the coolant stream enters at the end of the reactor at a temperature t a0, say 300 k. Veryhightemperature reactor vhtr among the 6 candidates of the gen iv nuclear systems in the technical roadmap of gen iv international forum gif, the very high temperature reactor vhtr is primarily dedicated to the cogeneration of electricity and hydrogen, the latter being extracted from water by using thermochemical, electrochemical or hybrid processes. However, there was no urgent or strong commercial demand, although the essential needs. Pdf design options for the advanced hightemperature reactor.
Advantages of very high temperature reactors clear passive safety mechanism 1. Goals, requirements, and design implications for the. A chemical reactor is an enclosed volume in which a chemical reaction takes place. Very high temperature reactor vhtr the very high temperature reactor vhtr is a graphitemoderated, heliumcooled reactor. History and promise of high temperature gas cooled reactors. Pdf the advanced hightemperature reactor ahtr is a new reactor concept under development that uses. Thermal hydraulics of the very high temperature gas cooled. Assume a coolant temperature at the entrance x 0, v 0 to the reactor t a2 340 k. There is currently one nuclear reactor under construction that is projected to come into service by 20 which is the watts bar 2 reactor in tennessee 1. Htr physics, including quantities to be determined and optimized in the design of nuclear reactors. The basecase design with prismatic fuel blocks is described.
In 2014, the generation iv international forum confirmed the very high temperature reactor vhtr as one of 6 promising reactor technologies that should be pursued in order to develop advanced reactors suitable for deployment in the 2030s. The practical guide on what to do right when biological influences cause a sequencing batch reactor to go wrong. The thorium high temperature reactor in germany operated for 4 years, and japans high temperature engineering test reactor demonstrated 850c outlet temperatures. Consequently, a detailed design of a fluidized bed reactor that would allow flexible operation at high temperature and high pressure at several gas velocities will be conducted in order to serve for the future development of new hydrodynamic models. The term typically refers to the next step in the evolutionary development of hightemperature gascooled reactors htgrs.
Next generation nuclear plant system requirements manual, idaho national. Thermophysical properties of a generation iv very high temperature reactor material pages. This plant design utilizes basic high temperature gascooled reactor htgr features of ceramic fuel, helium coolant, and a graphite moderator. Materials in generationiv very high temperature reactors. These tennis ballsized pebbles are made of pyrolytic graphite which acts as. Several reactors have been built or being constructed. In which hexagonal graphite blocks are stacked to fit in a cylindrical. The primary challenges of the vhtr are enumerated below. The crp will investigate and make proposals on modular high temperature gas cooled reactor htgr safety design criteria. For all irreversible reactions of greater than zero order, the volume of the reactor approaches. Still others are being developed at various stages, including. Lecture 9 reactor sizing chemical kinetics is the study of chemical reaction rates and reaction mechanisms. The very hightemperature reactor vhtr design descriptions, technology.
The moltensaltcooled advanced hightemperature reactor ahtr is a new reactor concept designed to provide very high temperature 750 to ec heat to enable efficient lowcost 1 thermochemical production of hydrogen h2 or 2 production of electricity. Moltensaltcooled advanced hightemperature reactor for. The high operating temperatures in a vhtr cause helium impurities to be aggravated. In many ways this book is a unique source of past experience, and hopefully, it will serve as an important part. A small modular nuclear reactor to replace coal plants could be on the market within 5 years. The high temperature reactor and process applications.
Reactors require much attention to safety details in the design process due to the hazards they impose. Futterer eu presented by frank carre france on behalf of the gif vhtr system steering committee michael. There are various iterations on this concept, most notably the vhtr very high temperature reactor, an iaea proposed generation iv design, the pebble bed reactor or the httr in all cases they share a number of common characteristics, so i shall group them under the umbrella of high temperature gas reactors htgrs. The inherent properties of the veryhightemperature reactor vhtr facilitate the design of the vhtr with high degree of passive safe performances, compared to other type of reactors.
Air ingress phenomena in a depressurization accident of. Comprised of 16 chapters, this book begins with a general description of the htr core as well as its performance limitations. An educational model of a small compact 4 th generation nuclear reactor is presented for use as an educational model in universities. The reactor design will be a graphite moderated, thermal neutron spectrum reactor that will produce electricity and hydrogen in a highly efficient manner. The status of hightemperature gascooled reactor development and design in the united states and other countries important benefits are foreseen from smaller, modular systems by l. Plutonium, thorium, including deep burn cycles with lwr spent fuel. It will supply heat with high core outlet temperatures which will enable applications such as hydrogen production and.
The construction began in december 2012 and the operation is expected in 2017. Modular high temperature gas reactor russia general atomics design 290 mwe prismatic core excess weapons plutonium burner in design phase in russia direct cycle start of construction depends on us gov funding maybe never. The veryhightemperature reactor vhtr, or hightemperature gascooled reactor htgr, is a generation iv reactor concept that uses a graphitemoderated nuclear reactor with a oncethrough uranium fuel cycle. High temperature process steam and process heat capability offer cogeneration opportunities now. The study of chemical reaction engineering cre combines the study of chemical kinetics with the reactors in which the reactions occur. Reactor design lectures notes university of technology, iraq. Development of hightemperature gascooled reactor htgr, also known as very hightemperature gascooled reactor vhtr for its generation iv designs, has continued for over half a century. Ceramics in nuclear applications ceramic engineering and. This richly illustrated, straightforward guide carries forth the legacy established by previous editions in the wiley wastewater microbiology series by focusing attention on the mixed gathering of organisms cohabitating within a sequencing. The present book is composed of chapters recalling the concept of the htr module.
Very high temperature reactor system inpro dialogue forum vienna, 14 april 2016 michael a. Layout of a high temperature reactor and strategy of introducing nuclear process heat. The safety goals are to equal or surpass those of the modular hightemperature gascooled reactor with a beyonddesignbasis accident capability to withstand large system and structural failures vessel failure, etc. The hightemperature gascooled reactor htgr is similar in concept to the. For the fullscale power reactor of 10 mwe, a monte carlo. Manual or computer automated image analysis is performed to measure the minimum. Technology assessments introduction high temperature reactor htr systems i. Volume stability, expansion, and shrinkage at high temperatures. Physics of hightemperature reactors 1st edition elsevier.
The basic design of pebblebed reactors features spherical fuel elements called pebbles. Water gas shift reactor design linkedin slideshare. This paper provides an initial description and technical analysis of its key features. No radial variation in reaction rate concentration and the reactor is.
Ssr21, vienna, 2012, and the deterministic and riskinformed safety design standards under. The physics of high temperature reactors, ebook isbn 9781483280288. It covers land based and marine based watercooled reactors, high temperature gas cooled reactors, liquid metal, sodium and gascooled fast neutron spectrum reactors and molten salt reactors. Once the kinetics is known, the reactor design can be made based on material balance. In any manufacturing process where there is a chemical change. In chemical engineering, it is generally understood to be a process vessel used to carry out a chemical reaction, which is one of the classic unit operations in chemical process analysis. It is expected that these criteria would refer to light water reactor safety standards e. Troubleshooting the sequencing batch reactor wiley. Module 9 operating experience corrosion studies, ope issues, remote handling, longterm storage module 10 safety analysis and design requirements msr events, accident sequences, hazards analysis, distributed source terms.
Yan, in handbook of generation iv nuclear reactors, 2016. The present very high temperature reactor vhtr, operating at 7500c. Draft preapplication safety evaluation report for the modular hightemperature gascooled reactor nureg38 was written in early 1989. It is a type of veryhightemperature reactor vhtr, one of the six classes of nuclear reactors in the generation iv initiative. A very important aspect of the design of a high temperature gas cooled reactor htr is to predict the neutronics of the reactor, as this determines the fission heat release. Laser melting of spark plasma sintered zirconium carbide. Development of very high temperature reactors for process heat supply. Significant efforts are underway in several member states to develop high temperature gas cooled reactors htgr based on either pebble bed or prismatic designs. Advances in small modular reactor technology developments. Graphite also has a high thermal conductivity, which facilitates the transfer of heat to the reflector, and it can withstand high temperatures. For an ideal cstr reactor, the residence time required for the reaction is given by.
S department of energy doe is conducting research on the very high temperature reactor vhtr design concept for the next generation nuclear plant ngnp project. The contraction or expansion of the refractories can take place during service life. Ingersoll, in handbook of small modular nuclear reactors, 2015. High temperature gas reactors an overview sciencedirect topics. Hightemperature reactors are very safe compared with other reactor systems, and a secondary shutdown system is not always.
Very high temperature reactor vhtr energy independence. The term typically refers to the next step in the evolutionary development of high temperature gascooled reactors htgrs. Trufueled very high temperature reactors for applications requiring an extended operation with minimized control and no refueling. The pebblebed reactor pbr is a design for a graphitemoderated, gascooled nuclear reactor. Gascooled reactors have had a long and varied history dating back to the very early days of nuclear energy development. The book chemical reactor design and control is based on the experience of author william. Key parameters and a representative graphic for the htrpm design are given in figure 2. Types there are two types of veryhightemperature reactors. In the mid1980s, doe turned to a smaller modular design a modular htgr with an annular core and steel rpv, and a conceptual design was completed in 1987. The very high temperature reactor the term very high temperature reactor vhtr loosely covers any reactor design with a coolant outlet temperature of c or above. Reactors jordan university of science and technology. The pebble bed reactor pbr design consists of fuel in the form of pebbles, stacked together in a cylindrical pressure vessel, like a gumball machine. Basic objectives in design of a reactor in chemical engineering physical operations such as fluid flow, heat transfer, mass transfer and separation processes play a very large part.
Although not a vhtr by coolant temperature, the twinunit 2. An ebook reader can be a software application for use on a computer such as microsofts free reader application, or a booksized computer that is used solely as a reading device such as nuvomedias rocket ebook. High temperature gas cooled reactor fuels and materials. Purchase physics of hightemperature reactors 1st edition. The high temperature gascooled reactor jrc publications.