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Sample records for alternative thorium fuel

  1. Alternative Thorium fuel cycle for LWRS

    International Nuclear Information System (INIS)

    In the paper, different thorium nuclear fuel cycles are examined and compared under light water reactor conditions, especially VVER-440. Two investigated thorium based fuels include one solely plutonium-thorium based fuel and the second one plutonium-thorium based fuel with initial uranium U-233 content. Both of them are used to carry and burn or transmute plutonium created in the classical UOX cycle. Different thorium fuel distribution in fuel assemblies is modeled - homogeneous and heterogenous. The article shows main features of VVER-440 reactor, analysed fuel assemblies and fuel cycles. Fuel cycles and fissile content in the fuel are tuned to fulfil operating conditions of VVER-440 reactor. The conclusion is concentrated on the rate of Pu transmutation and Pu with minor actinides cumulation in the spent thorium fuel and its comparison to UOX open fuel cycle. (authors)

  2. Abundant thorium as an alternative nuclear fuel

    International Nuclear Information System (INIS)

    It has long been known that thorium-232 is a fertile radioactive material that can produce energy in nuclear reactors for conversion to electricity. Thorium-232 is well suited to a variety of reactor types including molten fluoride salt designs, heavy water CANDU configurations, and helium-cooled TRISO-fueled systems. Among contentious commercial nuclear power issues are the questions of what to do with long-lived radioactive waste and how to minimize weapon proliferation dangers. The substitution of thorium for uranium as fuel in nuclear reactors has significant potential for minimizing both problems. Thorium is three times more abundant in nature than uranium. Whereas uranium has to be imported, there is enough thorium in the United States alone to provide adequate grid power for many centuries. A well-designed thorium reactor could produce electricity less expensively than a next-generation coal-fired plant or a current-generation uranium-fueled nuclear reactor. Importantly, thorium reactors produce substantially less long-lived radioactive waste than uranium reactors. Thorium-fueled reactors with molten salt configurations and very high temperature thorium-based TRISO-fueled reactors are both recommended for priority Generation IV funding in the 2030 time frame. - Highlights: • Thorium is an abundant nuclear fuel that is well suited to three advanced reactor configurations. • Important thorium reactor configurations include molten salt, CANDU, and TRISO systems. • Thorium has important nuclear waste disposal advantages relative to pressurized water reactors. • Thorium as a nuclear fuel has important advantages relative to weapon non-proliferation

  3. The use of thorium as an alternative nuclear fuel

    International Nuclear Information System (INIS)

    The use of thorium as an alternative or supplementary nuclear fuel is examined and compared with uranium. A description of various reactor types and their suitability to thorium fuel, and a description of various aspects of the fuel cycle from mining to waste disposal, are included. Comments are made on the safety and economics of each aspect of the fuel cycle and the extension of the lifetime of nuclear fuel

  4. A Preliminary Study on the Conceptual Design of Thorium/Uranium Mixed Nuclear Fuel for the Alternative of Burnable Poison in Commercial Pressurized Water Reactor

    International Nuclear Information System (INIS)

    Thorium has higher neutron absorption cross section than that of U-238. Thus, the thorium mixed uranium oxide nuclear fuel can reduce the initial excessive reactivity and the long-live radio-wastes with increasing the fuel utilization efficiency. In this study, a preliminary study on the application of the thorium/uranium mixed fuel is performed for the alternative of the PLUS7 fuel assembly which includes burnable poison. A conceptual design without geometrical change is proposed and the reactor characteristics are analyzed. In this study, a fuel assembly using the uranium/thorium mixed fuel was designed to substitute the assembly which includes burnable poison. The reactor characteristics, which are kinf, power distribution and plutonium production rate, were evaluated and the results are compared with the E1 assembly which is used in the OPR1000 reactor. The results show that the proposed design can efficiently reduce the excessive reactivity, peak power, and plutonium production with increasing the fuel utilization period

  5. Alternate Fuel Cycle Technologies/Thorium Fuel Cycle Technology Programs. Quarterly report for period 1 April--30 June 1978

    Energy Technology Data Exchange (ETDEWEB)

    Vondra, B.L.

    1978-08-01

    Voloxidation and dissolution studies: rotary-kiln heat-transfer tests are under way using a small rotary kiln along with the development of a mathematical model to determine kiln-heat-flux profiles necessary to maintain a desired temperature gradient. The erosion/corrosion test for evaluating materials of construction is operational. Fuel from a BWR (Big Rock Point) yielded more fine solid residue on dissolution than in previous tests with PWR fuel. Two additional parametric voloxidation tests with H.B. Robinson fuel compared air vs pure oxygen atmospheres at 550{sup 0}C; overall tritium release and subsequent fuel dissolution were equivalent. Thorium dissolution studies: the dissolution rate of thoria in fluoride-catalyzed 8 to 14 M HNO{sub 3} (100{sup 0}C) was max between 0.04 to 0.06 M HF; at higher fluoride concentrations, ThF{sub 4}.5H{sub 2}O precipitated. The rate of zircaloy dissolution continued to increase with increasing fluoride concentration. Stainless-steel-clad (Th,U)0{sub 2} fuel rods irradiated in the NRX reactor were sheared, voloxidized, and dissolved. {le}10% of the tritium was released during voloxidation in air at 600{sup 0}C. Carbon-14 removal from off-gas and fixation: carbon dioxide removal with Linde 13X molecular sieves to less than 100 ppB was experimentally verified using 300 ppM CO in air. Decontamination factors from 3000 to 7500 were obtained for CO{sub 2} removal in the gas-slurry stirred-tank reactor with CA(OH){sub 2}.or Ba(0H){sub 2}/sup .8H2O./. With Ba(OH){sub 2}.H{sub 2}0{sup 2} in a fixed-bed column, decontamination factors of about 30,000 were obtained.

  6. Thorium nuclear fuel cycle technology

    Energy Technology Data Exchange (ETDEWEB)

    Eom, Tae Yoon; Do, Jae Bum; Choi, Yoon Dong; Park, Kyoung Kyum; Choi, In Kyu; Lee, Jae Won; Song, Woong Sup; Kim, Heong Woo

    1998-03-01

    Since thorium produces relatively small amount of TRU elements after irradiation in the reactor, it is considered one of possible media to mix with the elements to be transmuted. Both solid and molten-salt thorium fuel cycles were investigated. Transmutation concepts being studied involved fast breeder reactor, accelerator-driven subcritical reactor, and energy amplifier with thorium. Long-lived radionuclides, especially TRU elements, could be separated from spent fuel by a pyrochemical process which is evaluated to be proliferation resistance. Pyrochemical processes of IFR, MSRE and ATW were reviewed and evaluated in detail, regarding technological feasibility, compatibility of thorium with TRU, proliferation resistance, their economy and safety. (author). 26 refs., 22 figs

  7. Research and development of thorium fuel cycle

    International Nuclear Information System (INIS)

    Nuclear properties of thorium are summarized and present status of research and development of the use of thorium as nuclear fuel is reviewed. Thorium may be used for nuclear fuel in forms of metal, oxide, carbide and nitride independently, alloy with uranium or plutonium or mixture of the compound. Their use in reactors is described. The reprocessing of the spent oxide fuel in thorium fuel cycle is called the thorex process and similar to the purex process. A concept of a molten salt fuel reactor and chemical processing of the molten salt fuel are explained. The required future research on thorium fuel cycle is commented briefly. (T.H.)

  8. Thorium fuel cycles in CANDU

    International Nuclear Information System (INIS)

    In recent years, Atomic Energy of Canada Limited has been examining in detail the implications of using thorium-based fuels tn the CANDU reactor. Various cycles initiated and enriched either with fissile plutonium or with enriched uranium, and with effective conversion ratios ranging up to 1.0, have been evaluated. We have concluded that: 1. Substantial quantities of uranium can be saved by adoption of the thorium fuel cycle, and the long-term security of fissile supply both for the domestic and overseas market can be considerably enhanced. The amount saved will depend on the details of the fuel cycle and the anticipated growth of nuclear power in Canada. 2. The fuel cycle can be introduced into the basic CANDU design without major modifications and without compromising current safety standards. 3. The economic conditions that make thorium competitive with the once-through natural uranium cycle depend a the price of uranium and on the costs both to fabricate α and γ-emitting fuels and to either enrich uranium or to extract fissile material from spent fuel. While timing is difficult to predict, we believe that competitive economic conditions will prevail toward the end of this century. 4. A twenty-year technological development program will be required to establish commercial confidence in the fuel cycle. (author)

  9. The economics of thorium fuel cycles

    International Nuclear Information System (INIS)

    The individual cost components and the total fuel cycle costs for natural uranium and thorium fuel cycles are discussed. The thorium cycles are initiated by using either enriched uranium or plutonium. Subsequent thorium cycles utilize recycled uranium-233 and, where necessary, either uranium-235 or plutonium as topping. A calculation is performed to establish the economic conditions under which thorium cycles are economically attractive. (auth)

  10. Material requirements for a thorium based nuclear fuel

    OpenAIRE

    Galiana Gonzalez, Bernat

    2010-01-01

    The increase in the energy consumption and the expected growth in the nuclear capacity make it necessary to look for alternative fuels to replace uranium. The fuel chosen, which was also considered in the early stages of nuclear energy, is thorium. Thorium has some characteristics that make it valuable as a fuel, like its abundance, the low radiotoxicity of the waste generated, the higher economy regarding its larger absorption cross-section and higher burnups and the prolifera...

  11. Thorium fuel cycle - Potential benefits and challenges

    International Nuclear Information System (INIS)

    There has been significant interest among Member States in developing advanced and innovative technologies for safe, proliferation resistant and economically efficient nuclear fuel cycles, while minimizing waste and environmental impacts. This publication provides an insight into the reasons for renewed interest in the thorium fuel cycle, different implementation scenarios and options for the thorium cycle and an update of the information base on thorium fuels and fuel cycles. The present TECDOC focuses on the upcoming thorium based reactors, current information base, front and back end issues, including manufacturing and reprocessing of thorium fuels and waste management, proliferation-resistance and economic issues. The concluding chapter summarizes future prospects and recommendations pertaining to thorium fuels and fuel cycles

  12. Thorium and the Third Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Dukert, Joseph M.

    1970-01-01

    This booklet discusses energy sources for nuclear power plants. Uranium-235 by itself will not be able to handle the energy needs. The two man-made supplements that can be used for nuclear power plants energy sources are plutonium and uranium-233. Uranium-233 is an isotope that appears as a result of radioactive decay after neutrons have been absorbed in thorium-232. This uranium-233 is called the third fuel.

  13. Implementation strategy of thorium fuel cycle - 005

    International Nuclear Information System (INIS)

    Nuclear power is called again as a countermeasure of climate change recently. Nuclear power does not emit carbon dioxide (CO2) when it generates electricity. However there are still existing concerns such as the nuclear proliferation, long-term radioactive waste. Nuclear power was not included as a technical method of CDM (clean development mechanism) of Kyoto protocol. The use of the thorium is expected to overcome these concerns. Even though thorium utilization was known in the very early stage of nuclear application in 1940's, thorium was not used as primary source due to its lack of fissile material. Plenty amount of plutonium stock in the spent nuclear fuel from more than 50 years operation of the uranium fuel cycle can be used as starter of thorium fuel cycle. Declaration of the 'world without nuclear weapon' by the president Obama will also help to use weapon grade plutonium for starting thorium fuel cycle. In this paper, I will discuss how much amount of thorium cycle can be implemented triggered by the plutonium stock in spent nuclear fuel and by the weapon grade plutonium. Several implementation scenarios of thorium fuel cycle will be considered. Several types of molten-salt reactor were candidates of thorium nuclear power plant. The capacity of the thorium fuel cycle is estimated to be 450 GWe around at 2050. Some additional discussions on reducing carbon dioxide emission will be carried on rare-earth mining and electric vehicle in view of thorium utilization. (author)

  14. Thorium based fuel for AHWR

    International Nuclear Information System (INIS)

    Advanced Heavy Water Reactor (AHWR) is a 300 MWe, thoria fuel based, vertical pressure tube type reactor designed at BARC. It is heavy water moderated and boiling light water cooled reactor that has been designed for hundred years of plant life. The reactor design has evolved from the presently operating PHWRs and BWRs in India. AHWR has extensive deployment of passive safety features for its operation and accident mitigation at par with the present international standards and provides a robust design against external as well as internal threats. The physics design ensures inherent safety characteristics of the reactor. Heat removal from the core under both normal full power operating condition as well as shutdown condition is by natural circulation of water coolant. The physical characteristics of Thoria based fuel offer potential for high performance in reactor and slower fuel deterioration. With inherent feature of fuel cycle flexibility, a variety of fuel-types could be used in AHWR for generating power efficiently. AHWR-Pu version makes use of (Th-Pu) MOX and (Th-233U) MOX fuel in the closed fuel cycle mode. The adoption of the closed thorium fuel cycle on an industrial scale is for the first time and is important in view of very little global experience. The experience generated on the various fuel cycle activities will be useful in utilisation of the large thoria reserves as envisaged in India's three-stage nuclear power programme. This paper provides an overview of the various design aspects of the thorium based fuel for AHWR and its associated developmental activities. (author)

  15. Pressurized water reactor thorium fuel cycle studies

    International Nuclear Information System (INIS)

    The use of a thorium fuel cycle in a PWR is studied. The thorium has no fissile isotope and a fissile nuclide must be added to the thorium fuel. This nuclide can be uranium 235, plutonium 239 or uranium 233. In this work we have kept the fuel assembly geometry and the control rod system of an usual PWR. Cell calculations showed that the moderation ratio of an usual PWR can be used with uranium 235 and plutonium 239 fuels. But this moderation ratio must be decreased and accordingly the pumping power must be increased in the case of a uranium 233 fuel. The three fuels can be controlled with soluble boron. The power distribution inside an assembly agrees with the safety rules and the worth of the control rods is sufficient. To be interesting the thorium fuels must be recycled. Because the activity and the residual power are higher for a thorium fuel than for a uranium fuel the shielding of the shipping casks and storage pools must be increased. The Uranium 235-Thorium fuel is the best even if it needs expensive enrichment work. With this type of fuel more natural uranium is saved. The thorium fuel would become very interesting if we observe again in the future an increase of the uranium cost

  16. A review on the status of development in thorium-based nuclear fuels

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Young Woo; Na, S. H.; Lee, Y. W.; Kim, H. S.; Kim, S. H.; Joung, C.Y

    2000-02-01

    Thorium as an alternative nuclear energy source had been widely investigated in the 1950s-1960s because it is more abundant than uranium, but the studies of thorium nuclear fuel cycle were discontinued by political and economic reasons in the 1970s. Recently, however, renewed interest was vested in thorium-based nuclear fuel cycle because it may generate less long-lived minor actinides and has a lower radiotoxicity of high level wastes after reprocessing compared with the thorium fuel cycle. In this state-of the art report, thorium-based nuclear cycle. In this state-of the art report, thorium-based nuclear fuel cycle and fuel fabrication processes developed so far with different reactor types are reviewed and analyzed to establish basic technologies of thorium fuel fabrication which could meet our situation. (author)

  17. A review on the status of development in thorium-based nuclear fuels

    International Nuclear Information System (INIS)

    Thorium as an alternative nuclear energy source had been widely investigated in the 1950s-1960s because it is more abundant than uranium, but the studies of thorium nuclear fuel cycle were discontinued by political and economic reasons in the 1970s. Recently, however, renewed interest was vested in thorium-based nuclear fuel cycle because it may generate less long-lived minor actinides and has a lower radiotoxicity of high level wastes after reprocessing compared with the thorium fuel cycle. In this state-of the art report, thorium-based nuclear cycle. In this state-of the art report, thorium-based nuclear fuel cycle and fuel fabrication processes developed so far with different reactor types are reviewed and analyzed to establish basic technologies of thorium fuel fabrication which could meet our situation. (author)

  18. Thorium as a nuclear fuel. Chapter 10

    International Nuclear Information System (INIS)

    Thorium-based nuclear power, despite several decades of research and development, has yet to be fully commercialized. In recent years, renewed interest in the potential advantages of thorium-based nuclear power has spurred research and development on several concepts for advanced reactors using thorium fuels, including high-temperature gas-cooled reactors, molten salt reactors, Canada Deuterium Uranium-type reactors, advanced heavy water reactors, fast breeder reactors, and pressurized heavy water reactors. If demand for thorium increases due to favorable reactor designs, then thorium can be supplied through byproduct recovery from deposits mined for other valuable mineral resources. As prominent examples, thorium-bearing monazite ((rare earth elements, Th) PO4) is an accessory mineral in many deposits of rare earth elements and heavy-mineral sands. (author)

  19. Moving towards sustainable thorium fuel cycles

    International Nuclear Information System (INIS)

    The CANDU reactor has an unsurpassed degree of fuel-cycle flexibility as a consequence of its fuel-channel design, excellent neutron economy, on-power refueling, and simple fuel bundle design. These features facilitate the introduction and full exploitation of thorium fuel cycles in CANDU reactors in an evolutionary fashion. Thoria (ThO2) based fuel offers both fuel performance and safety advantages over urania (UO2) based fuel, due its higher thermal conductivity which results in lower fuel-operating temperatures at similar linear element powers. Thoria fuel has demonstrated lower fission gas release than UO2 under similar operating powers during test irradiations. In addition, thoria has a higher melting point than urania and is far less reactive in hypothetical accident scenarios owing to the fact that it has only one oxidation state. This paper examines one possible strategy for the introduction of thorium fuel cycles into CANDU reactors. In the short term, the initial fissile material would be provided in a heterogeneous bundle of low-enriched uranium and thorium. The medium term scenario uses homogeneous Pu/Th bundles in the CANDU reactor, further increasing the energy derived from the thorium. In the long term, the full energy potential from thorium would be realized through the recycle of the U-233 in the used fuel. With U-233 recycle in CANDU reactors, plutonium would then only be required to top up the fissile content to achieve the desired burnup. (author)

  20. Practical introduction of thorium fuel cycles

    International Nuclear Information System (INIS)

    The pracitcal introduction of throrium fuel cycles implies that thorium fuel cycles compete economically with uranium fuel cycles in economic nuclear power plants. In this study the reactor types under consideration are light water reactors (LWRs), heavy water reactors (HWRs), high-temperature gas-cooled reactors (HTGRs), and fast breeder reactors (FBRs). On the basis that once-through fuel cycles will be used almost exclusively for the next 20 or 25 years, introduction of economic thorium fuel cycles appears best accomplished by commercial introduction of HTGRs. As the price of natural uranium increases, along with commercialization of fuel recycle, there will be increasing incentive to utilize thorium fuel cycles in heavy water reactors and light water reactors as well as in HTGRs. After FBRs and fuel recycle are commercialized, use of thorium fuel cycles in the blanket of FBRs appears advantageous when fast breeder reactors and thermal reactors operate in a symbiosis mode (i.e., where 233U bred in the blanket of a fast breeder reactor is utilized as fissile fuel in thermal converter reactors)

  1. Thorium fuel cycle study for PWR applications

    International Nuclear Information System (INIS)

    A nuclear design feasibility of thorium fueled high converting PWR was investigated. Two kinds of fuel design option were tested for the comparison with conventional UO2 fuel. The first one was an application of MHTGR pyro-carbon coated particle fuels. The other design was an application of MOX fuels as a ThO2-PuO2 ceramic pellet. In the case of carbon-coated particle fuels, there was no benefit in nuclear design aspect because enrichment of U-235 was required over 5 w/o in order to match with the K-infinite of Ulchin-3/4 fuels. However, the use of thorium based plutonium fuels in PWR gave favorable aspects in nuclear design such as flatter K-infinite curve, lower M. T. C. and lower F. T. C. than that of UO2 fuel. (author). 6 refs., 3 tabs., 6 figs

  2. Thorium fuel cycle study for PWR applications

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Jae Yong; Kim, Myung Hyun [Kyung Hee Univ., Seoul (Korea, Republic of)

    1997-12-31

    A nuclear design feasibility of thorium fueled high converting PWR was investigated. Two kinds of fuel design option were tested for the comparison with conventional UO{sub 2} fuel. The first one was an application of MHTGR pyro-carbon coated particle fuels. The other design was an application of MOX fuels as a ThO{sub 2}-PuO{sub 2} ceramic pellet. In the case of carbon-coated particle fuels, there was no benefit in nuclear design aspect because enrichment of U-235 was required over 5 w/o in order to match with the K-infinite of Ulchin-3/4 fuels. However, the use of thorium based plutonium fuels in PWR gave favorable aspects in nuclear design such as flatter K-infinite curve, lower M. T. C. and lower F. T. C. than that of UO{sub 2} fuel. (author). 6 refs., 3 tabs., 6 figs.

  3. Experience of thorium fuel development in India

    International Nuclear Information System (INIS)

    India has one of the largest resources of thorium in the beach sands of Southern India. Generation of nuclear power through utilization of thorium is the ultimate goal of India's three stage nuclear power strategy. Bhabha Atomic Research Centre (BARC) is actively pursuing research, development, fabrication, characterization and irradiating testing of ThO2, ThO2-PuO2, ThO2-UO2 fuels in test and power reactors. Work related to developing the fuel fabrication technology including automation and remotization needed for 233U based fuels is in progress. Use of ThO2 fuel bundles for initial flux flattening in our PHWRs; recent criticality of KAMINI - a small neutron source reactor, with 233U-Al alloy fuel; introduction of ThO2 as axial and radial blankets in our Fast Breeder Test Reactor (FBTR) at Kalpakkam; proposed ThO2-PuO2 and ThO2-233UO2 fuel for Advanced Heavy Water Reactor (AHWR) are some of the steps taken by us towards utilization of Thorium in India. The paper summarizes the present status of thorium fuel development in India. (author)

  4. Reprocessing in the thorium fuel cycle

    International Nuclear Information System (INIS)

    An overview of the authors personal view is presented on open questions in regard to still required research and development work for the thorium fuel cycle before its application in a technical-industrial scale may be tackled. For a better understanding, all stations of the back-end of the thorium fuel cycle are briefly illustrated and their special features discussed. They include storage and transportation measures, all steps of reprocessing, as well as the entire radioactive waste treatment. Knowledge gaps are, as far as they are obvious, identified and proposals put forward for additional worthwile investigations. (orig.)

  5. Candu reactors with thorium fuel cycles

    International Nuclear Information System (INIS)

    Over the last decade and a half AECL has established a strong record of delivering CANDU 6 nuclear power plants on time and at budget. Inherently flexible features of the CANDU type reactors, such as on-power fuelling, high neutron economy, fuel channel based heat transport system, simple fuel bundle configuration, two independent shut down systems, a cool moderator and a defence-in-depth based safety philosophy provides an evolutionary path to further improvements in design. The immediate milestone on this path is the Advanced CANDU ReactorTM** (ACRTM**), in the form of the ACR-1000TM**. This effort is being followed by the Super Critical Water Reactor (SCWR) design that will allow water-cooled reactors to attain high efficiencies by increasing the coolant temperature above 5500C. Adaptability of the CANDU design to different fuel cycles is another technology advantage that offers an additional avenue for design evolution. Thorium is one of the potential fuels for future reactors due to relative abundance, neutronics advantage as a fertile material in thermal reactors and proliferation resistance. The Thorium fuel cycle is also of interest to China, India, and Turkey due to local abundance that can ensure sustainable energy independence over the long term. AECL has performed an assessment of both CANDU 6 and ACR-1000 designs to identify systems, components, safety features and operational processes that may need to be modified to replace the NU or SEU fuel cycles with one based on Thorium. The paper reviews some of these requirements and the associated practical design solutions. These modifications can either be incorporated into the design prior to construction or, for currently operational reactors, during a refurbishment outage. In parallel with reactor modifications, various Thorium fuel cycles, either based on mixed bundles (homogeneous) or mixed channels (heterogeneous) have been assessed for technical and economic viability. Potential applications of a

  6. Comparison of the radiological hazard of thorium and uranium spent fuels from VVER-1000 reactor

    International Nuclear Information System (INIS)

    Thorium fuel is considered as a viable alternative to the uranium fuel used in the current generation of nuclear power plants. Switch from uranium to thorium means a complete change of composition of the spent nuclear fuel produced as a result of the fuel depletion during operation of a reactor. If the Th–U fuel cycle is implemented, production of minor actinides in the spent fuel is negligible. This is favourable for the spent fuel disposal. On the other hand, thorium fuel utilisation is connected with production of 232U, which decays via several alpha decays into a strong gamma emitter 208Tl. Presence of this nuclide might complicate manipulations with the irradiated thorium fuel. Monte-Carlo computation code MCNPX can be used to simulate thorium fuel depletion in a VVER-1000 reactor. The calculated actinide composition will be analysed and dose rate from produced gamma radiation will be calculated. The results will be compared to the reference uranium fuel. Dependence of the dose rate on time of decay after the end of irradiation in the reactor will be analysed. This study will compare the radiological hazard of the spent thorium and uranium fuel handling. - Highlights: • Spent thorium and uranium fuel composition in VVER-1000 was calculated by MCNPX. • Important nuclide 208Tl is not included in the thorium spent fuel composition. • There are large differences in activity of actinides between spent Th and U fuels. • Dose rate from spent thorium fuel is increasing during 50 years of decay. • 208Tl in spent thorium fuel increased the dose rate by several percent

  7. Thorium fuel cycle concept for KAERI's accelerator driven system project

    International Nuclear Information System (INIS)

    Korea Atomic Energy Research Institute (KAERI) has been carrying out accelerator driven system related research and development called HYPER for transmutation and energy production. HYPER program is aiming to develop the elemental technologies for the subcritical system by 2001 and build a small bench scale test facility (∼5MW(th)) by the year 2006. Some major features of HYPER have been developed and employed, which are on-power fueling concepts, a hollow cylinder-type metal fuel, and Pb-Bi as a coolant and spallation target material. Another fuel cycle concept for HYPER has been also studied to utilize thorium as a molten salt form to produce electricity as well as to transmute TRU elements. At the early stage of the fuel cycle, fissile plutonium isotopes in TRU will be incinerated to produce energy and to breed 233U from thorium. Preliminary calculation showed that periodic removal of fission products and small amount of TRU addition could maintain the criticality without separation of 233Pa. At the end of the fuel cycle, the composition of fissile plutonium isotopes in TRU was significantly reduced from about 60% to 18%, which is not attractive any more for the diversion of plutonium. Thorium molten salt fuel cycle may be one of the alternative fuel cycles for the transmutation of TRU. The TRU remained at the end of fuel cycle can be incinerated in HYPER having fast neutron spectrums. (author)

  8. A Commercial Thorium-based Fuel for LWRs

    International Nuclear Information System (INIS)

    fuel which undergoes such extensive isotopic degradation as to not warrant further recycle steps. - Capturing the U233 energy content of spent 'TOP' fuel can be deferred for many years since its fissile quality does not diminish with time. The introduction of MOX fuel has paved the way for TOP fuel, both from a technical viewpoint and in terms of its licensing. It is foreseen that any reactor that can be licensed for MOX fuel would also be able to operate with TOP fuel in a straight-forward manner. The technique for manufacture of fresh TOP fuel will not differ significantly from that used for making MOX fuel. In summary, Thor Energy is taking the first steps towards introducing thorium-based fuel for the current generation of LWRs by establishing a competitive alternative to the MOX fuels of today. (authors)

  9. Evaluation of thorium based nuclear fuel. Chemical aspects

    International Nuclear Information System (INIS)

    This report describes the chemical aspects of a thorium-based fuel cycle. It is part of a series devoted to the study of thorium-based fuel as a means to achieve a considerable reduction of the radiotoxicity of the waste from nuclear power production. Therefore special emphasis is placed on fuel (re-)fabrication and fuel reprocessing in the present work. (orig.)

  10. Comparison of the radiological hazard of thorium and uranium spent fuels from VVER-1000 reactor

    Science.gov (United States)

    Frybort, Jan

    2014-11-01

    Thorium fuel is considered as a viable alternative to the uranium fuel used in the current generation of nuclear power plants. Switch from uranium to thorium means a complete change of composition of the spent nuclear fuel produced as a result of the fuel depletion during operation of a reactor. If the Th-U fuel cycle is implemented, production of minor actinides in the spent fuel is negligible. This is favourable for the spent fuel disposal. On the other hand, thorium fuel utilisation is connected with production of 232U, which decays via several alpha decays into a strong gamma emitter 208Tl. Presence of this nuclide might complicate manipulations with the irradiated thorium fuel. Monte-Carlo computation code MCNPX can be used to simulate thorium fuel depletion in a VVER-1000 reactor. The calculated actinide composition will be analysed and dose rate from produced gamma radiation will be calculated. The results will be compared to the reference uranium fuel. Dependence of the dose rate on time of decay after the end of irradiation in the reactor will be analysed. This study will compare the radiological hazard of the spent thorium and uranium fuel handling.

  11. Thorium fuel-cycle studies for CANDU reactors

    International Nuclear Information System (INIS)

    The high neutron economy of the CANDU reactor, its ability to be refuelled while operating at full power, its fuel channel design, and its simple fuel bundle provide an evolutionary path for allowing full exploitation of the energy potential of thorium fuel cycles in existing reactors. AECL has done considerable work on many aspects of thorium fuel cycles, including fuel-cycle analysis, reactor physics measurements and analysis, fuel fabrication, irradiation and PIE studies, and waste management studies. Use of the thorium fuel cycle in CANDU reactors ensures long-term supplies of nuclear fuel, using a proven, reliable reactor technology. (author)

  12. Towards the thorium fuel cycle with molten salt fast reactors

    International Nuclear Information System (INIS)

    Highlights: • Neutronic calculations for fast spectrum molten salt reactor. • Evaluation of the fissile matter to be used in such reactor as initial fissile load. • Capabilities to transmute transuranic elements. • Deployment scenarios of the Thorium fuel cycle. • Waste management optimization with molten salt fast reactor. - Abstract: There is currently a renewed interest in molten salt reactors, due to recent conceptual developments on fast neutron spectrum molten salt reactors (MSFRs) using fluoride salts. It has been recognized as a long term alternative to solid-fueled fast neutron systems with a unique potential (large negative temperature and void coefficients, lower fissile inventory, no initial criticality reserve, simplified fuel cycle, wastes reduction etc.) and is thus one of the reference reactors of the Generation IV International Forum. In the MSFR, the liquid fuel processing is part of the reactor where a small side stream of the molten salt is processed for fission product removal and then returned to the reactor. Because of this characteristic, the MSFR can operate with widely varying fuel compositions, so that the MSFR concept may use as initial fissile load, 233U or enriched uranium or also the transuranic elements currently produced by light water reactors. This paper addresses the characteristics of these different launching modes of the MSFR and the Thorium fuel cycle, in terms of safety, proliferation, breeding, and deployment capacities of these reactor configurations. To illustrate the deployment capacities of the MSFR concept, a French nuclear deployment scenario is finally presented, demonstrating that launching the Thorium fuel cycle is easily feasible while closing the current fuel cycle and optimizing the long-term waste management via stockpile incineration in MSRs

  13. Strategy for the practical utilization of thorium fuel cycles

    International Nuclear Information System (INIS)

    There has been increasing interest in the utilization of thorium fuel cycles in nuclear power reactors for the past few years. This is due to a number of factors, the chief being the recent emphasis given to increasing the proliferation resistance of reactor fuel cycles and the thorium cycle characteristic that bred 233U can be denatured with 238U (further, a high radioactivity is associated with recycle 233U, which increases fuel diversion resistance). Another important factor influencing interest in thorium fuel cycles is the increasing cost of U3O8 ores leading to more emphasis being placed on obtaining higher fuel conversion ratios in thermal reactor systems, and the fact that thorium fuel cycles have higher fuel conversion ratios in thermal reactors than do uranium fuel cycles. Finally, there is increasing information which indicates that fast breeder reactors have significantly higher capital costs than do thermal reactors, such that there is an economic advantage in the long term to have combinations of fast breeder reactors and high-conversion thermal reactors operating together. Overall, it appears that the practical, early utilization of thorium fuel cycles in power reactors requires commercialization of HTGRs operating first on stowaway fuel cycles, followed by thorium fuel recycle. In the longer term, thorium utilization involves use of thorium blankets in fast breeder reactors, in combination with recycling the bred 233U to HTGRs (preferably), or to other thermal reactors

  14. Performance of Energy Multiplier Module (EM2) with long-burn thorium fuel cycle

    International Nuclear Information System (INIS)

    Energy Multiplier Module (EM2) is a helium-cooled fast reactor being developed by General Atomics for the 21st century grid. It is designed as a modular plant with a net electric output of 265 MWe with an evaporative heat sink and 240 MWe with an air-cooled heat sink. EM2 core performance is examined for the baseline loading of low-enriched uranium (LEU) as fissile material with depleted uranium (DU) as fertile material and compared to the alternate LEU with thorium loading. The latter has two options: a heterogeneous loading of thorium fuel in the place of DU that produces a longer fuel cycle, and homogeneously mixed thorium-uranium fuel loading. Compared to the baseline LEU/DU core, the cycle length of both thorium options is reduced due to higher neutron absorptions by thorium. However, for both, heterogeneous and homogenous thorium loading options, the fuel cycle length is over 24 years without refueling or reshuffling of fuel assemblies. The physics properties of the EM2 thorium core are close to those of the baseline core which constitute low excess reactivity, negative fuel temperature coefficient, and very small void reactivity. However, unlike the case of baseline EM2, the homogeneous thorium fuel loading provides additional advantage in reducing the power peaking of the core, which in turn reduces the cladding material neutron damage rate by 23%. It is interpreted that the relatively slow 233U buildup as compared to 239Pu for baseline core retards reactivity increase without the need for a complicated fuel loading pattern of the heterogeneous fuel loading, while maintaining the peak power density low. Therefore both the heterogeneous and homogeneous thorium loading options will be feasible in the EM2

  15. Potential synergy: the thorium fuel cycle and rare earths processing

    International Nuclear Information System (INIS)

    The use of thorium in nuclear power programs has been evaluated on a recurring basis. A concern often raised is the lack of 'thorium infrastructure'; however, for at least a part of a potential thorium fuel cycle, this may less of a problem than previously thought. Thorium is frequently encountered in association with rare earth elements and, since the U.S. last systematically evaluated the large-scale use of thorium (the 1970's,) the use of rare earth elements has increased ten-fold to approximately 200,000 metric tons per year. Integration of thorium extraction with rare earth processing has been previously described and top-level estimates have been done on thorium resource availability; however, since ores and mining operations differ markedly, what is needed is process flowsheet analysis to determine whether a specific mining operation can feasibly produce thorium as a by-product. Also, the collocation of thorium with rare earths means that, even if a thorium product stream is not developed, its presence in mining waste streams needs to be addressed and there are previous instances where this has caused issues. This study analyzes several operational mines, estimates the mines' ability to produce a thorium by-product stream, and discusses some waste management implications of recovering thorium. (authors)

  16. An assessment of once-through homogeneous thorium fuel economics for light water reactors

    International Nuclear Information System (INIS)

    The fuel economics of an once-through homogeneous thorium fuel concept for PWR was assessed by doing a detailed core analysis. In addition to this, the fuel economics assessment was also performed for two other ways enhancing the economic potential of thorium fuel; thorium utilization in the mixed core with uranium fuel assembly and Duplex thorium fuel concepts. As a results of fuel economics assessment, the thorium fuel cycle does not show any economic incentives in preference to uranium fuel cycle under the 18-months fuel cycle for PWR. However, the utilization of thorium is the mixed core with uranium fuel assembly and Duplex thorium fuel cycle and show superior fuel economics to uranium fuel under the longer fuel cycle scheme. The economic potential of once-through thorium fuel cycle is expected to be increased further by utilizing the Duplex thorium fuel in the mixed core with uranium fuel assembly

  17. Dynamic Analysis of the Thorium Fuel Cycle in CANDU Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Chang Joon; Park, Chang Je

    2006-02-15

    The thorium fuel recycle scenarios through the Canada deuterium uranium (CANDU) reactor have been analyzed for two types of thorium fuel: homogeneous ThO{sub 2}UO{sub 2} and ThO{sub 2}UO{sub 2}-DUPIC fuels. The recycling is performed through the dry process fuel technology which has a proliferation resistance. For the once-through fuel cycle model, the existing nuclear power plant construction plan was considered up to 2016, while the nuclear demand growth rate from the year 2016 was assumed to be 0%. After setting up the once-through fuel cycle model, the thorium fuel CANDU reactor was modeled to investigate the fuel cycle parameters. In this analysis, the spent fuel inventory as well as the amount of plutonium, minor actinides and fission products of the multiple recycling fuel cycle were estimated and compared to those of the once-through fuel cycle. From the analysis results, it was found that the closed or partially closed thorium fuel cycle can be constructed through the dry process technology. Also, it is known that both the homogeneous and heterogeneous thorium fuel cycles can reduce the SF accumulation and save the natural uranium resource compared with the once-through cycle. From the material balance view point, the heterogeneous thorium fuel cycle seems to be more feasible. It is recommended, however, the economic analysis should be performed in future.

  18. IRIS reactor core with thorium fuel

    International Nuclear Information System (INIS)

    This work is aimed at running the first IRIS reactor core with mixed thorium dioxide fuel (ThO2-UO2 and ThO2-PuO2). Calculations are performed by using Dragon 4.0.4 and Citation codes. The results show the multiplication factor(Keff) for central and peripheral assemblies as a function of burnup. To ensure the proliferation resistance,the value of 235U enrichment is ≤ 20%. The Keff is calculated using Dragon 4.0.4 for a single fuel rod and the model developed to fuel assembly, while the whole core was calculated using Citation code. For a fuel burnup, the use of increased enrichment fuel in the IRIS core leads to high reserve of reactivity, which is compensated with an integral fuel burnable absorber. The self-shielding of boron is in an IRIS reactor fuel. The effect of increased enrichment to the burn-up rates, and burnable poison distribution on the reactor performance, are evaluated. The equipment used in traditional light water reactors is evaluated for designing a small unit IRIS reactor. (authors)

  19. Thorium-based nuclear fuel: current status and perspectives

    International Nuclear Information System (INIS)

    Until the present time considerable efforts have already been made in the area of fabrication, utilization and reprocessing of Th-based fuels for different types of reactors, namely: by FRG and USA - for HTRs; FRG and Brazil, Italy - for LWRs; India - for HWRs and FBRs. Basic research of thorium fuels and thorium fuel cycles are also being undertaken by Australia, Canada, China, France, FRG, Romania, USSR and other countries. Main emphasis has been given to the utilization of thorium fuels in once-through nuclear fuel cycles, but in some projects closed thorium-uranium or thorium-plutonium fuel cycles are also considered. The purpose of the Technical Committee on the Utilization of Thorium-Based Nuclear Fuel: Current Status and Perspective was to review the world thorium resources, incentives for further exploration, obtained experience in the utilization of Th-based fuels in different types of reactors, basic research, fabrication and reprocessing of Th-based fuels. As a result of the panel discussion the recommendations on future Agency activities and list of major worldwide activities in the area of Th-based fuel were developed. A separate abstract was prepared for each of the 9 papers in this proceedings series

  20. Assessment of thorium fuel cycles in pressurized water reactors. Final report

    International Nuclear Information System (INIS)

    Alternate thorium fuel cycles were evaluated on a consistent basis in a Combustion Engineering Standard System 80 plant to provide a base-line for comparison of resource utilization with the conventional uranium cycle and with more advanced concepts. The economic motivation and the technical feasibility of employing thorium-based fuels in present PWRs were also determined. In order to achieve a significant increase in generating capacity for a given uranium ore resource, thorium utilization must be widespread. This necessitates the use of thorium cycles employing highly-enriched uranium; increases in the energy generated per mined ton of ore on the order of 18 to 34 percent can be realized in the long term with these fuel cycles. Increases in energy generation for the highly-enriched uranium/thorium fuel cycles are obtained, however, at the expense of higher separative work requirements (about 25 percent) and higher uranium ore requirements during the early cycles. As a consequence, greater 30-year levelized fuel cycle costs are obtained for these fuel cycles. Cycles employing plutonium enrichment have a more limited long term impact on uranium ore utilization because of the large fraction of the nuclear generating capacity which must be operated on the conventional uranium cycle to provide start-up and makeup plutonium inventories. However, about 20 percent more energy can be generated per kilogram of plutonium consumed in the thorium cycle than in the uranium cycle, and hence the thorium-based cycle represents a superior way of utilizing existing plutonium stockpiles. Comparison of the characteristics of uranium- and thorium-based cores indicates that thorium fueling is feasible, and modifications to PWRs designed to accommodate plutonium recycle do not appear to be required

  1. Preliminary Neutronics Analysis Of Fuel Pebble With Thorium Fuel Cycle

    International Nuclear Information System (INIS)

    A new fuel pebble was designed based on Thorium fuel cycle. 231Pa has been added into fuel pebble for obtaining the minimum reactivity swing. The results show that the new designed pebble fuel with 7.0 % 233U enrichment adding 3.2% 231Pa, the keff is to be controlled up to 65 GWd/t; the other design with 8.0 % 233U enrichment requires 3.9% 231Pa, the keff therefore is remain up to 80 GWd/t. About 95% of loaded 231Pa in fuel pebble is depleted after 120 GWd/t. The results imply that it is optimistic to design the fuel pebble with 233U, 231Pa and 232Th; but some effects such as fuel temperature effect, distribution of TRISO particle in pebble fuel, etc. are required to investigate. (author)

  2. An evaluation of once-through homogeneous thorium fuel cycle for light water reactors

    International Nuclear Information System (INIS)

    The other ways enhancing the economic potential of thorium fuel has been assessed ; the utilization of lower enriched uranium in thorium-uranium fuel, duplex thorium fuel concept, thorium utilization in the mixed core with uranium fuel assembly and thorium blanket utilization in the uranium core. The fuel economics of the proposed ways of thorium fuel increased compared to the previous homogeneous thorium fuel cycle. Compared to uranium fuel cycle, however, they do not show any economic incentives. From the view of proliferation resistance potential, thorium fuel option has the advantage to reduce the inventory of plutonium production. Any of proposed thorium options are less economical than uranium fuel option, the thorium fuel option has the potential to be utilized in the future for the sake of the effective consumption of excessive plutonium and the preparation against the using up of uranium resource

  3. Thorium fuel cycle studies: fuel fabrication process and cost estimation

    International Nuclear Information System (INIS)

    Early in 1976 a study was made to assess the relative economics and fuel utilization of thorium and uranium fuel cycles in various types of reactors. It was to be completed in approximately two months, so all component parts had to be developed in a short time with a high degree of dependence on existing information. One of the components required for the study was a consistent set of relatively accurate fuel fabrication costs for the various reactor-fuel combinations. A report documents the rationale used in generating these cost estimates and presents in some detail the basis and methodology employed. Since three types of thermal flux reactors (LWR, HWR, and HTGR) and two types of fast flux reactors (liquid metal and gas cooled) together with three fuel forms (oxides, carbides, and metal) were included in the study with various combinations of the fissionable metals U, Th, and Pu, it was necessary to define a methodology that would permit a rapid relative estimate for each case. Existing cost studies were chosen for a Light-Water Reactor with low-enriched uranium fuel and for a High-Temperature Gas-Cooled Reactor with highly enriched uranium and thorium fuel as the reference cases which could be compared with other reactor-fuel combinations

  4. Thorium fuel cycle studies: fuel fabrication process and cost estimation

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, A.R.

    1979-09-01

    Early in 1976 a study was made to assess the relative economics and fuel utilization of thorium and uranium fuel cycles in various types of reactors. It was to be completed in approximately two months, so all component parts had to be developed in a short time with a high degree of dependence on existing information. One of the components required for the study was a consistent set of relatively accurate fuel fabrication costs for the various reactor-fuel combinations. A report documents the rationale used in generating these cost estimates and presents in some detail the basis and methodology employed. Since three types of thermal flux reactors (LWR, HWR, and HTGR) and two types of fast flux reactors (liquid metal and gas cooled) together with three fuel forms (oxides, carbides, and metal) were included in the study with various combinations of the fissionable metals U, Th, and Pu, it was necessary to define a methodology that would permit a rapid relative estimate for each case. Existing cost studies were chosen for a Light-Water Reactor with low-enriched uranium fuel and for a High-Temperature Gas-Cooled Reactor with highly enriched uranium and thorium fuel as the reference cases which could be compared with other reactor-fuel combinations.

  5. Some research and development of thorium fuel cycle in Russia

    International Nuclear Information System (INIS)

    There has recently been increasing interest in implementation of thorium into nuclear power. Among the new areas of that interest research in the field of nuclear fuel resources, safety improvement of nuclear reactors and their ecological acceptability should be mentioned. Many specialists consider the proliferation resistance to be the main advantage of thorium fuel cycle. In particular, this advantage leads to some proposals to use thorium-plutonium-based reactor fuel for plutonium utilization. This paper presents an overview of investigation, which are under way at the State Scientific Center - Institute of Physics and Power Engineering in Obninsk, Russia. (author)

  6. Evaluation of thorium based nuclear fuel. Extended summary

    International Nuclear Information System (INIS)

    Application of thorium based nuclear fuels has been evaluated with emphasis on possible reduction of the actinide waste. As a result three ECN-reports are published, discussing in detail: - The reactor physics aspects, by comparing the operation characteristics of the cores of Pressurized Water Reactors and Heavy Water Reactors with different fuel types, including equilibrium thorium/uranium free, once-through uranium fuel and equilibrium uranium/plutonium fuel, - the chemical aspects of thorium based fuel cycles with emphasis on fuel (re)fabrication and fuel reprocessing, - the possible reduction in actinide waste as analysed for Heavy Water Reactors with various types of thorium based fuels in once-through operation and with reprocessing. These results are summarized in this report together with a short discussion on non-proliferation and uranium resource utilization. It has been concluded that a substantial reduction of actinide radiotoxicity of the disposed waste may be achieved by using thorium based fuels, if very efficient partitioning and multiple recycling of uranium and thorium can be realized. This will, however, require large efforts to develop the technology to the necessary industrial scale of operation. (orig.)

  7. Future perspective of thorium based nuclear fuels and thorium potential of Turkey

    International Nuclear Information System (INIS)

    Today's nuclear technology has principally been based on the use of fissile U-235 and Pu-239. The existence of thorium in the nature and its potential use in the nuclear technology were not unfortunately into account with a sufficient importance. The global distributions of thorium and uranium reserves indicate that in general some developed countries such as the USA, Canada, Australia, France have considerable uranium reserves, and contrarily only some developing countries such as Turkey, Brazil, India, Egypt have considerable thorium reserves. The studies carried out on the thorium during the last 50 years have clearly showed that the thorium based nuclear fuels have the potential easily use in most of reactor types actually operated with the classical uranium based nuclear fuels without any considerable modification. In the case of the use of thorium based nuclear fuels in future nuclear energy production systems, the serious problems such as the excess of Pu-239, the proliferation potential of nuclear weapons, and also the anxious of nuclear terrorism will probably be resolved, and sustainable nuclear energy production will be realized in the next new century. (authors)

  8. Integral benchmarks with reference to thorium fuel cycle

    International Nuclear Information System (INIS)

    This is a power point presentation about the Indian participation in the CRP 'Evaluated Data for the Thorium-Uranium fuel cycle'. The plans and scope of the Indian participation are to provide selected integral experimental benchmarks for nuclear data validation, including Indian Thorium burn up benchmarks, post-irradiation examination studies, comparison of basic evaluated data files and analysis of selected benchmarks for Th-U fuel cycle

  9. Irradiation of thorium based fuels at research reactors of Trombay

    International Nuclear Information System (INIS)

    Utilization of large thorium reserve of our country for power production had been a prime goal from the inception of our three stage nuclear power programme. This long term policy is well reflected in irradiation programme of Thoria and Thorium rods at research reactors Cirus and Dhruva, located at Trombay. The first batch of Thorium/Thoria rods were loaded in Cirus reactor on August 28, 1960, immediately after attaining first criticality on July 10, 1960 which reflects the priority the Thorium utilization programme received from our planners. The programme was aimed for gaining sufficient experience with Thorium fuel cycle by the time our first stage of nuclear power programme attained maturity. In Cirus, these rods are irradiated in the annular gap, called J-rod annulus, between the two graphite reflectors around the pile. About 200 Thorium/Thoria rods had been irradiated in Cirus before the reactor was shut down permanently on 31st December 2010. A few Thoria assemblies have also been irradiated in fuel positions of Dhruva reactor. Apart from these, a few fuel assemblies made of ThO2, PuO2 and UO2 were irradiated in Pressurized Water Loop of Cirus to study fuel and clad behavior under high temperature and pressure, before their induction in power programme. Presently, fuel cluster with AHWR type Th-Pu and Th-LEU MOX fuel pins are being irradiated in a regular fuel position of Dhruva for obtaining vital information and experience related to Thorium based MOX fuel cycle. This paper highlights the experience gained in irradiation of Thoria/Thorium rods, expected yield of 233U, contamination level of 232U and handling of these assemblies at research reactors Cirus and Dhruva. (author)

  10. Thorium fueled high temperature gas cooled reactors. An assessment

    International Nuclear Information System (INIS)

    The use of thorium as a fertile fuel for the High Temperature Gas Cooled Reactor (HTR) instead of uranium has been reviewed. It has been concluded that the use of thorium might be beneficial to reduce the actinide waste production. To achieve a real advancement, the uranium of the spent fuel has to be recycled and the requested make-up fissile material for the fresh fuel has to be used in the form of highly-enriched uranium. A self-sustaining fuel cycle may be possible in the HTR of large core size, but this could reduce the inherent safety features of the design. (orig.)

  11. Ultra-long cycle SMART core design using thorium fuel

    International Nuclear Information System (INIS)

    A ultra-long cycle(5 years) SMART core design is examined using the thorium fuel. Most of design configurations of SMART core such as fuel loading pattern, control rod management strategy, and burnable absorber material remain unchanged but uranium fuel which is replaced with a homogeneous mixture of 20% enriched uranium and thorium. The number of burnable absorber pins of the thorium loaded SMART core was adjusted to control the excess reactivity during the cycle burnup. It was shown that mixing ratio of 40:60 of uranium fuel and thorium fuel is necessary to achieve a 5 year cycle length of SMART core. The results also show that the ultra-longer cycle SMART core satisfying all design constraints such as Fq less than 2.5, axial offset less than 0.3, keff less than 0.95 when refueling shutdown margin of 1% with most reactive control rod stuck, and ejected rod worth less than 250 pcm, are possible by using thorium fuel and absorber materials effectively

  12. Comparison for thorium fuel cycle facilities of two different capacities for implementation of safeguards

    International Nuclear Information System (INIS)

    Highlights: • Facilities for implementation of safeguards for thorium fuel cycle have been compared. • Two concepts have been compared. • In one concept, the facilities are designed in hub and spoke concept. • In second concept the facilities are designed as self-contained concept. • The comparison is done on a number of factors, which affect safeguardability and proliferation resistance. -- Abstract: Thorium based nuclear fuel cycle has many attractive features, its inherent proliferation resistance being one of them. This is due to the presence of high energy gamma emitting daughter products of U232 associated with U233. This high energy gamma radiation also poses challenges in nuclear material accounting. A typical thorium fuel cycle facility has a number of plants including a fuel fabrication plant for initial and equilibrium core, a reprocessed U233 fuel fabrication plant, a reprocessing plant, a fuel assembly/disassembly plant and associated waste handling and management plants. A thorium fuel cycle facility can be set up to serve reactors at a site. Alternatively, one can follow a hub and spoke approach with a large thorium fuel cycle facility acting as a hub, catering to the requirements of reactors at several sites as spokes. These two concepts have their respective merits and shortcomings in terms of engineering and economics. The present paper is aimed at comparing the merits and challenges for implementation of safeguards on the two concepts viz. a large fuel cycle hub catering to reactors at several sites versus a small fuel cycle facility dedicated to reactors at a single site

  13. Thorium based fuel options for the generation of electricity: Developments in the 1990s

    International Nuclear Information System (INIS)

    The IAEA has maintained an interest in the thorium fuel cycle and its worldwide utilization within its framework of activities. Periodic reviews have assessed the current status of this fuel cycle, worldwide applications, economic benefits, and perceived advantages with respect to other nuclear fuel cycles. Since 1994, the IAEA convened a number of technical meetings on the thorium fuel cycle and related issues. Between 1995 and 1997 individual contributions on the thorium fuel cycle were elicited from experts from France, Germany, India, Japan, the Russian Federation and the USA. These contributions included evaluations of the status of the thorium fuel cycle worldwide; the new incentives to use thorium due to large stockpiles of plutonium produced in nuclear reactors; new reactor concepts utilizing thorium; strategies for thorium use; and an evaluation of toxicity of the thorium fuel cycle waste compared to that from other fuel cycles. The results of this updated evaluation are summarized in this publication

  14. Transmutation of minor actinide using thorium fueled BWR core

    International Nuclear Information System (INIS)

    One of the methods to conduct transmutation of minor actinide is the use of BWR with thorium fuel. Thorium fuel has a specific behaviour of producing a little secondary minor actinides. Transmutation of minor actinide is done by loading it in the BWR with thorium fuel through two methods, namely close recycle and accumulation recycle. The calculation of minor actinide composition produced, weigh of minor actinide transmuted, and percentage of reminder transmutation was carried SRAC. The calculations were done to equivalent cell modeling from one fuel rod of BWR. The results show that minor actinide transmutation is more effective using thorium fuel than uranium fuel, through both close recycle and accumulation recycle. Minor actinide transmutation weight show that the same value for those recycle for 5th recycle. And most of all minor actinide produced from 5 unit BWR uranium fuel can transmuted in the 6th of close recycle. And, the minimal value of excess reactivity of the core is 12,15 % Δk/k, that is possible value for core operation

  15. Thorium-Based Fuel Cycles in the Modular High Temperature Reactor

    Institute of Scientific and Technical Information of China (English)

    CHANG Hong; YANG Yongwei; JING Xingqing; XU Yunlin

    2006-01-01

    Large stockpiles of civil-grade as well as weapons-grade plutonium have been accumulated in the world from nuclear power or other programs of different countries. One alternative for the management of the plutonium is to incinerate it in the high temperature reactor (HTR). The thorium-based fuel cycle was studied in the modular HTR to reduce weapons-grade plutonium stockpiles, while producing no additional plutonium or other transuranic elements. Three thorium-uranium fuel cycles were also investigated. The thorium absorption cross sections of the resolved and unresolved resonances were generated using the ZUT-DGL code based on existing resonance data. The equilibrium core of the modular HTR was calculated and analyzed by means of the code VSOP'94. The results show that the modular HTR can incinerate most of the initially loaded plutonium amounting to about 95.3% net 239Pu for weapons-grade plutonium and can effectively utilize the uranium and thorium in the thorium-uranium fuel cycles.

  16. Uranium thorium dioxide fuel-cycle and economic analysis

    International Nuclear Information System (INIS)

    The fuel division of Framatome ANP (Advanced Nuclear Power) is performing a fuel-cycle analysis for uranium-thorium dioxide (U/Th) reactor fuel as part of a U.S. Department of Energy Nuclear Energy Research Initiative project titled, ''Advanced Proliferation Resistant, Lower Cost, Uranium-Thorium Dioxide Fuels for Light Water Reactor'', (DE-FC03-99SF21916). The objective is to evaluate the economic viability of the U/Th fuel cycle in commercial nuclear reactors operating in the U.S. This analysis includes formulating the evaluation methodology, validating the methodology via benchmark calculations, and performing a fuel-cycle analysis and corresponding economic evaluation. The APOLLO2-F computer program of Framatome ANP SCIENCE package was modified to incorporate the thorium decay chains and provide cross sections for the SCIENCE fuel-cycle analysis. A comparison and economic evaluation was made between UO2 and UO2/ThO2 fuel cycles in a typical 193-fuel assembly pressurized water reactor using reload batch sizes corresponding to batch average discharge burnups of 50, 70, and 90 GWd/mtHM. Results show an increase in front-end costs for the UO2/ThO2 cycles due primarily to the higher cost in separative work units for enriching the uranium to 19.5 wt% 235U. (author)

  17. Thorium Energy Futures

    OpenAIRE

    Peggs, S.; Horak, W.; Roser, T.; Ashley, V.B.; Ashworth, R.F.; Barlow, Roger; Cywinski, R.; Seviour, Rebecca; Biarrotte, J.-L.; Henderson, S.; Hutton, A; Kelly, J; Lindroos, M.; McIntyre, P. M.; Norlin, A.

    2012-01-01

    The potential for thorium as an alternative or supplement to uranium in fission power generation has long been recognised, and several reactors, of various types, have already operated using thorium-based fuels. Accelerator Driven Subcritical (ADS) systems have benefits and drawbacks when compared to conventional critical thorium reactors, for both solid and molten salt fuels. None of the four options – liquid or solid, with or without an accelerator – can yet be rated as better or worse than...

  18. Analysis of alternative light water reactor (LWR) fuel cycles

    International Nuclear Information System (INIS)

    Nine alternative LWR fuel cycles are analyzed in terms of the isotopic content of the fuel material, the relative amounts of primary and recycled material, the uranium and thorium requirements, the fuel cycle costs and the fraction of energy which must be generated at secured sites. The fuel materials include low-enriched uranium (LEU), plutonium-uranium (MOX), highly-enriched uranium-thorium (HEU-Th), denatured uranium-thorium (DU-Th) and plutonium-thorium (Pu-Th). The analysis is based on tracing the material requirements of a generic pressurized water reactor (PWR) for a 30-year period at constant annual energy output. During this time period all the created fissile material is recycled unless its reactivity worth is less than 0.2% uranium enrichment plant tails

  19. Recent advances in thorium fuel cycles for CANDU reactors

    International Nuclear Information System (INIS)

    The once-through thorium fuel cycle in CANDU reactors provides an evolutionary approach to exploiting the energy potential of thorium. In the 'mixed bundle' strategy, the central 8 elements in a CANFLEX fuel bundle contain thoria, while the outermost 35 elements contain slightly enriched uranium (SEU). Detailed full-core fuel-management simulations have shown that this approach can be successfully implemented in existing CANDU reactors. Uranium requirements are lower than for the natural uranium fuel cycle. Further energy can be derived from the thorium by recycling the irradiated thoria fuel elements, containing 233U, as-is without any processing, into the center of a new mixed bundle. There are several examples of such 'demountable' bundles. Recycle of the central 8 thoria elements results in an additional burnup of 20 MW·d/kgHE from the thoria elements, for each recycle. The reactivity of these thoria elements remains remarkably constant over irradiation for each recycle. The natural uranium requirements for the mixed bundle (which includes the natural uranium feed required for the outer SEU fuel elements), without recycle, is about 10% lower than for the natural uranium fuel cycle. After the first recycle, the uranium requirements are -35% lower than for the natural uranium cycle, and remain fairly constant with further recycling (the total uranium requirement averaged over a number of cycles is 30% lower than a natural uranium fuelled CANDU reactor). This thorium cycle strategy is a cost-effective means of reducing uranium requirements, while producing a stockpile of valuable 233U, safeguarded in the spent fuel, that can be recovered in the future when predicated by economic or resource considerations. (author)

  20. Preliminary economic evaluation of thorium based fuels in PWRs

    OpenAIRE

    Du Toit, M.H.; Cilliers, A.C.

    2014-01-01

    Many studies have proven that thorium-based fuel cycles are more expensive than current uranium fuel cycles, which is confirmed in this paper as well. This research, however, goes beyond the conventional nuclear plant refueling cycle, aiming to optimize the refueling cycle in line with specific advantages realized from the thoriumbased refueling cycle. These benefits are the good thermal neutronic characteristics of fertile 232Th and fissile 233U, resulting in longer r...

  1. Status of the Norwegian thorium light water reactor (LWR) fuel development and irradiation test program

    International Nuclear Information System (INIS)

    Thorium based fuels offer several benefits compared to uranium based fuels and should thus be an attractive alternative to conventional fuel types. In order for thorium based fuel to be licensed for use in current LWRs, material properties must be well known for fresh as well as irradiated fuel, and accurate prediction of fuel behavior must be possible to make for both normal operation and transient scenarios. Important parameters are known for fresh material but the behaviour of the fuel under irradiation is unknown particularly for low Th content. The irradiation campaign aims to widen the experience base to irradiated (Th,Pu)O2 fuel and (Th,U)O2 with low Th content and to confirm existing data for fresh fuel. The assumptions with respect to improved in-core fuel performance are confirmed by our preliminary irradiation test results, and our fuel manufacture trials so far indicate that both (Th,U)O2 and (Th,Pu)O2 fuels can be fabricated with existing technologies, which are possible to upscale to commercial volumes

  2. Thorium fuel studies for CANDU reactors

    International Nuclear Information System (INIS)

    Applying the once-through Thorium (OTT) cycle in existing and advanced CANDU reactors might be seen as an evolved concept for the sustainable development both from the economic and waste management points of view. Using the Canadian proposed scheme - loading mixed ThO2-SEU CANFLEX bundles in CANDU 6 reactors - simulated at lattice cell level led to promising conclusions on higher burnup, lesser actinide inventory and proliferation resistance. The calculations were performed using the lattice codes WIMS and DRAGON (together with the corresponding nuclear data library based on ENDF/B-VII). (authors)

  3. Study and suggestions on development of the thorium fuel cycle in China

    International Nuclear Information System (INIS)

    The features of thorium fuel cycle are analyzed and an overview of development of the thorium fuel cycle is carried out. On the basis of detailed analyses on potentials of utilizing thorium resources in all kinds of reactors, suggestions on development of the thorium fuel cycle in our country are put forward following the outlook of sustainable development of nuclear energy: (1) current reactors can't make full use of thorium resources from industrial viewpoints other than HTRs; (2) an advanced synergic fuel cycle of fast reactors and thermal reactors is suggested to utilize thorium resources; (3) more R and D efforts should be devoted on advanced and immature reactor technologies instead of the thorium utilization of these reactors; (4) currently much fundamental research work on the thorium utilization should be done. (authors)

  4. Introduction of Thorium in the Nuclear Fuel Cycle. Short- to long-term considerations

    International Nuclear Information System (INIS)

    Since the beginning of the nuclear era, significant scientific attention has been given to thorium's potential as a nuclear fuel. Although the thorium fuel cycle has never been fully developed, the opportunities and challenges that might arise from the use of thorium in the nuclear fuel cycle are still being studied in many countries and in the context of diverse international programmes around the world. This report provides a scientific assessment of thorium's potential role in nuclear energy both in the short to longer term, addressing diverse options, potential drivers and current impediments to be considered if thorium fuel cycles are to be pursued. (authors)

  5. Review of Brazilian activities related to the thorium fuel cycle and production of thorium compounds at IPEN-CNEN/SP

    International Nuclear Information System (INIS)

    The Brazilian's interest in the nuclear utilization of thorium has started in the 50's as a consequence of the abundant occurrence of monazite sands. Since the sixties, IPEN-CNEN/SP has performed some developments related to the thorium fuel cycle. The production and purification of thorium compounds was carried out at IPEN for about 18 years and the main product was the thorium nitrate with high purity, having been produced over 170 metric tons of this material in the period, obtained through solvent extraction. The thorium nitrate was supplied to the domestic industry and used for gas portable lamps (Welsbach mantle). Although the thorium compounds produced have not been employed in the nuclear area, several studies were conducted. Therefore, those activities and the accumulated experience are of strategic importance, on one hand due to huge Brazilian thorium reserves, on the other hand by the resurgence of the interest of thorium for the Generation IV Advanced Reactors. This paper presents a review of the Brazilian research and development activities related to thorium technology. (author)

  6. Thorium-based fuel cycles: reassessment of fuel economics andproliferation risk

    OpenAIRE

    Serfontein, Dawid E.; Mulder, Eben J.

    2014-01-01

    At current consumption and current prices, the proven reserves for natural uranium will last only about 100 years. However, the more abundant thorium, burned in breeder reactors, such as large High Temperature Gas-Cooled Reactors, and followed by chemical reprocessing of the spent fuel, could stretch the 100 years for uranium supply to 15,000 years. Thorium-based fuel cycles are also viewed as more proliferation resistant compared to uranium. However, several barriers to entry caused all coun...

  7. Part 4. Safety implications of alternative fuel types

    International Nuclear Information System (INIS)

    This report provides an assessment of safety implications associated with alternatives relative to the reference (U,Pu) oxide fuel in fast breeder reactors. The alternatives considered include thorium- and uranium-based oxide, carbide and metal fuel types for the LMFBR and oxide fuel types for the GCFR. Major emphasis is put on low probability, but potentially large-consequence accidents, e.g., core-disruptive accidents

  8. Treatment of uranium-thorium fuel at its production stage

    International Nuclear Information System (INIS)

    The possibility of removing 232U at the stage of obtaining 233U for the convenience of processing and reducing radiation dose has been analyzed in the paper. This problem is solved by the technology of obtaining 233U in extracted neutron beams in cold channels of a reactor. This technology will allow the acceleration of the implementation of the uranium-thorium fuel cycle in the current reactor technologies

  9. Alternative fuel information sources

    Energy Technology Data Exchange (ETDEWEB)

    1994-06-01

    This short document contains a list of more than 200 US sources of information (Name, address, phone number, and sometimes contact) related to the use of alternative fuels in automobiles and trucks. Electric-powered cars are also included.

  10. Design analysis of a thorium fueled reactor with seed-blanket assembly configuration

    International Nuclear Information System (INIS)

    Recently, thorium is receiving increasing attention as an important fertile material for the expanding nuclear power programs around the world. The superior nuclear and physical properties of thorium-based fuels could lead to very low fuel cycle cost and make thorium reactors economically attractive. In addition, the use of thorium in reactors would permit more efficient utilization of low cost uranium reserves and reduction of nuclear wastes. In this work, the nuclear characteristics of a new type of thorium fueled reactor (Radkowsky Thorium Reactor) consisting of seed-blanket assemblies are addressed and compared with those of typical assemblies of a PWR (CE type). Also, an assessment on several advantages of thorium fueled reactors is provided. All these results are based on the HELIOS code calculation

  11. Thorium

    Science.gov (United States)

    Wickleder, Mathias S.; Fourest, Blandine; Dorhout, Peter K.

    In 1815 Berzelius analyzed a rare mineral from the Falun district. He assumed that the mineral contained a new element, which he named thorium after the ancient Scandinavian god of thunder and weather, Thor (Weeks and Leicester, 1968).

  12. Thorium is an ultimate source of energy

    OpenAIRE

    Kim, HungGeun; Lee, Sangcheol

    2013-01-01

    This article is written for readers to help the understanding of thorium as an alternative source of nuclear energy. Thorium (Thorium) can be applied for reactor fuels and thorium energy development such as ADSR; Accelerator Driven Subcritical Reactor. This particle explains the thorium as a possible choice to replace of uranium to supply enormous energy could be the energy source. A Korean article published in "Science Times" in South Korea. The article is based on an interview ...

  13. 3.4. Research and Development of Thorium in Nuclear Fuel -European Commission

    OpenAIRE

    Tsige-Tamirat, Haileyesus

    2012-01-01

    Thorium fuel cycles (ThFCs) have been investigated with varying intensity for many different reactor types in the past.This was motivated by the vast abundance of thorium and its ability to be used as a fertile material in most reactor types. Thorium oxide fuel possesses favorable neutronic, thermal and chemical properties that could enable higher fuel utilization, lower minor actinide production, and improved proliferation resistance. Past studies in the European Union indicated that Th...

  14. Thorium fuel cycle technology for molten salt reactor systems

    International Nuclear Information System (INIS)

    Molten Salt Reactor (MSR) is classified as the non-classical nuclear type based on the specific featured coming out from the use of liquid fuel circulating in the MSR primary circuit. Other uniqueness of the reactor type is based on the fact that the primary or fuel circuit of the reactor in operation for a long run. MSR is the only reactor system, which can be operated with thorium fuel within the pure 232Th - 233U fuel cycle with the breeding factor significantly higher than one. It can bring several advantages, mainly in the radioactive waste management, thanks to minimized production higher actinides. With respects to all these facts and features, the fuel cycle aspects of MSR system are quite complicated, especially if the technology shall guarantee all possible advantages of MSR system concurrently with good economy, technological safety and reliability and inevitable proliferation resistance

  15. Radiotoxicity Characterization of Multi-Recycled Thorium Fuel - 12394

    International Nuclear Information System (INIS)

    As described in companion papers, Westinghouse is proposing the implementation of a thorium based fuel cycle to burn the transuranic (TRU) contained in the used nuclear fuel. The potential of thorium as a TRU burner is described in another paper presented at this conference. This paper analyzes the long-term impact of thorium on the front-end and backend of the fuel cycle. This is accomplished by an assessment of the isotopic make-up of Th in a closed cycle and its impact on representative metrics, such as radiotoxicity, decay heat and gamma heat. The behavior in both thermal and fast neutron energy ranges has been investigated. Irradiation in a Th fuel PWR has been assumed as representative of the thermal range, while a Th fuel fast reactor (FR) has been employed to characterize the behavior in the high-energy range. A comparison with a U-fuel closed-cycle FR has been undertaken in an attempt of a more comprehensive evaluation of each cycle's long-term potential. As the Th fuel undergoes multiple cycles of irradiation, the isotopic composition of the recycled fuel changes. Minor Th isotopes are produced; U-232 and Pa-231 build up; the U vector gradually shifts towards increasing amounts of U-234, U-235 etc., eventually leading to the production of non negligible amounts of TRU isotopes, especially Pu-238. The impact of the recycled fuel isotopic makeup on the in-core behavior is mild, and for some aspects beneficial, i.e. the reactivity swing during irradiation is reduced as the fertile characteristics of the fuel increase. On the other hand, the front and the back-end of the fuel cycle are negatively affected due to the presence of Th-228 and U-232 and the build-up of higher actinides (Pu-238 etc.). The presence of U-232 can also be seen as advantageous as it represents an obstacle to potential proliferators. Notwithstanding the increase in the short-term radiotoxicity and decay heat in the multi-recycled fuel, the Th closed cycle has some potentially substantial

  16. Spent fuel characteristics analysis for thorium-uranium breeding recycle in PWRs

    International Nuclear Information System (INIS)

    Spent fuel characteristics analyses of thorium-based fuel were investigated using ORIGEN-S code compared with uranium-based fuel. Such parameters as radio- activity, radiotoxicity, decay heat, and gamma ray were considered. Relative results in this work could provide some reference information for storage, reprocessing and disposal of thorium-based spent fuel. Four type fuels, thorium-based fuel U3ThOX (mixed reactor grade 233U-thorium oxide), PuThOX (mixed reactor grade plutonium-thorium oxide), uranium-based fuel UOX (uranium oxide) and MOX (mixed reactor grade plutonium-uranium oxide), on the basis of core designs for thorium-uranium breeding recycle in PWRs were investigated. The calculated results show that: 1) Due to extremely low content of transuranic nuclides, the radiotoxicity of U3ThOX is dramatically lower than that of three other types of spent fuel in 1000 years after discharge; 2) In thorium-based spent fuel the intensity of gamma ray near 2.6 MeV mainly generated by 208Tl in 232U decay chain is much stronger than that in uranium-based fuel. The intensity of γ ray near 2.6 MeV reaches a local peak in about 10 years after discharge when the reprocessing should not be performed for thorium-based spent fuel. (authors)

  17. Thorium

    International Nuclear Information System (INIS)

    General mineralogical-geochemical and analytical characteristics of thorium are presented. It is stressed that the main trend in the development of analytical methods for determining Th in mineral raw material is the use of physical methods of the analysis. To separate Th from RE, Zr, U being its permanent companions, precipitation, extraction and ion exchange are used. Principal methods of geologic samples dissolution are considered. Some techniques of radiometric, emanation, (by thoron), neutron activation, fluorescence X-ray spectral, spectrographic, gravimetric, photometric (with arsenazo 3) thorium determinations are described

  18. Study of an ADS Loaded with Thorium and Reprocessed Fuel

    Directory of Open Access Journals (Sweden)

    Graiciany de Paula Barros

    2012-01-01

    Full Text Available Accelerator-driven systems (ADSs are investigated for long-lived fission product transmutation and fuel regeneration. The aim of this paper is to investigate the nuclear fuel evolution and the neutronic parameters of a lead-cooled accelerator-driven system used for fuel breeding. The fuel used in some fuel rods was T232hO2 for U233 production. In the other fuel rods was used a mixture based upon Pu-MA, removed from PWR-spent fuel, reprocessed by GANEX, and finally spiked with thorium or depleted uranium. The use of reprocessed fuel ensured the use of T232hO2 without the initial requirement of U233 enrichment. In this paper was used the Monte Carlo code MCNPX 2.6.0 that presents the depletion/burnup capability, combining an ADS source and kcode-mode (for criticality calculations. The multiplication factor (keff evolution, the neutron energy spectra in the core at BOL, and the nuclear fuel evolution during the burnup were evaluated. The results indicated that the combined use of T232hO2 and reprocessed fuel allowed U233 production without the initial requirement of U233 enrichment.

  19. Alternative Fuels: Research Progress

    Directory of Open Access Journals (Sweden)

    Maher A.R. Sadiq Al-Baghdadi

    2013-01-01

    Full Text Available Chapter 1: Pollutant Emissions and Combustion Characteristics of Biofuels and Biofuel/Diesel Blends in Laminar and Turbulent Gas Jet Flames. R. N. Parthasarathy, S. R. Gollahalli Chapter 2: Sustainable Routes for The Production of Oxygenated High-Energy Density Biofuels from Lignocellulosic Biomass. Juan A. Melero, Jose Iglesias, Gabriel Morales, Marta Paniagua Chapter 3: Optical Investigations of Alternative-Fuel Combustion in an HSDI Diesel Engine. T. Huelser, M. Jakob, G. Gruenefeld, P. Adomeit, S. Pischinger Chapter 4: An Insight into Biodiesel Physico-Chemical Properties and Exhaust Emissions Based on Statistical Elaboration of Experimental Data. Evangelos G. Giakoumis Chapter 5: Biodiesel: A Promising Alternative Energy Resource. A.E. Atabani Chapter 6: Alternative Fuels for Internal Combustion Engines: An Overview of the Current Research. Ahmed A. Taha, Tarek M. Abdel-Salam, Madhu Vellakal Chapter 7: Investigating the Hydrogen-Natural Gas Blends as a Fuel in Internal Combustion Engine. ?lker YILMAZ Chapter 8: Conversion of Bus Diesel Engine into LPG Gaseous Engine; Method and Experiments Validation. M. A. Jemni , G. Kantchev , Z. Driss , R. Saaidia , M. S. Abid Chapter 9: Predicting the Combustion Performance of Different Vegetable Oils-Derived Biodiesel Fuels. Qing Shu, ChangLin Yu Chapter 10: Production of Gasoline, Naphtha, Kerosene, Diesel, and Fuel Oil Range Fuels from Polypropylene and Polystyrene Waste Plastics Mixture by Two-Stage Catalytic Degradation using ZnO. Moinuddin Sarker, Mohammad Mamunor Rashid

  20. Evaluation of U-Zr hydride fuel for a thorium fuel cycle in an RTR concept

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kyung Taek; Cho, Nam Zin [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

    1998-12-31

    In this paper, we performed a design study of a thorium fueled reactor according to the design concept of the Radkowsky Thorium Reactor (RTR) and evaluated its overall performance. To enhance its performance and alleviate its problems, we introduced a new metallic uranium fuel, uranium-zirconium hydride (U-ZrH{sub 1.6}), as a seed fuel. For comparison, typical ABB/CE-type PWR based on SYSTEM 80+and standard RTR-type thorium reactor were also studied. From the results of performance analysis, we could ascertain advantages of RTR-type thorium fueled reactor in proliferation resistance, fuel cycle economics, and back-end fuel cycle. Also, we found that enhancement of proliferation resistance and safer operating conditions may be achieved by using the U-ZrH{sub 1.6} fuel in the seed region without additional penalties in comparison with the standard RTR`s U-Zr fuel. 6 refs., 2 figs., 6 tabs. (Author)

  1. Outlook for alternative transportation fuels

    Energy Technology Data Exchange (ETDEWEB)

    Gushee, D.E. [Univ. of Illinois, Chicago, IL (United States)

    1996-12-31

    This presentation provides a brief review of regulatory issues and Federal programs regarding alternative fuel use in automobiles. A number of U.S. DOE initiatives and studies aimed at increasing alternative fuels are outlined, and tax incentives in effect at the state and Federal levels are discussed. Data on alternative fuel consumption and alternative fuel vehicle use are also presented. Despite mandates, tax incentives, and programs, it is concluded alternative fuels will have minimal market penetration. 7 refs., 5 tabs.

  2. Alternative fuel cycles

    International Nuclear Information System (INIS)

    Uranium resource utilization and economic considerations provide incentives to study alternative fuel cycles as future options to the PHWR natural uranium cycle. Preliminary studies to define the most favourable alternatives and their possible introduction dates are discussed. The important and uncertain components which influence option selection are reviewed, including nuclear capacity growth, uranium availability and demand, economic potential, and required technological developments. Finally, a summary of Ontario Hydro's program to further assess cycle selection and define development needs is given. (auth)

  3. High-quality thorium TRISO fuel performance in HTGRs

    International Nuclear Information System (INIS)

    Thorium as a nuclear fuel has received renewed interest, because of its widespread availability and the good irradiation performance of Th and mixed (Th,U) oxide compounds as fuels in nuclear power systems. Early HTGR development employed thorium together with high-enriched uranium (HEU). After 1980, HTGR fuel systems switched to low-enriched uranium (LEU). After completing fuel development for the AVR and the THTR with BISO coated particles, the German program expanded its efforts utilizing thorium and HEU TRISO coated particles in advanced HTGR concepts for process heat applications (PNP) and direct-cycle electricity production (HHT). The combination of a low-temperature isotropic (LTI) inner and outer pyrocarbon layers surrounding a strong, stable SiC layer greatly improved manufacturing conditions and the subsequent contamination and defective particle fractions in production fuel elements. In addition, this combination provided improved mechanical strength and a higher degree of solid fission product retention, not known previously with high-temperature isotropic (HTI) BISO coatings. The improved performance of the HEU (Th, U)O2 TRISO fuel system was successfully demonstrated in three primary areas of development: manufacturing, irradiation testing under normal operating conditions, and accident simulation testing. In terms of demonstrating performance for advanced HTGR applications, the experimental failure statistic from manufacture and irradiation testing are significantly below the coated particle requirements specified for PNP and HHT designs at the time. Covering a range to 1300 C in normal operations and 1600 C in accidents, with burnups to 13% FIMA and fast fluences to 8 x 1025 n/m2 (E> 16 fJ), the performance results exceed the design limits on manufacturing and operational requirements for the German HTR-Modul concept, which are 6.5 x 10-5 for manufacturing, 2 x 10-4 for normal operating conditions, and 5 x 10-4 for accident conditions. These

  4. High-quality thorium TRISO fuel performance in HTGRs

    Energy Technology Data Exchange (ETDEWEB)

    Verfondern, Karl [Forschungszentrum Juelich GmbH (Germany); Allelein, Hans-Josef [Forschungszentrum Juelich GmbH (Germany); Technische Hochschule Aachen (Germany); Nabielek, Heinz; Kania, Michael J.

    2013-11-01

    Thorium as a nuclear fuel has received renewed interest, because of its widespread availability and the good irradiation performance of Th and mixed (Th,U) oxide compounds as fuels in nuclear power systems. Early HTGR development employed thorium together with high-enriched uranium (HEU). After 1980, HTGR fuel systems switched to low-enriched uranium (LEU). After completing fuel development for the AVR and the THTR with BISO coated particles, the German program expanded its efforts utilizing thorium and HEU TRISO coated particles in advanced HTGR concepts for process heat applications (PNP) and direct-cycle electricity production (HHT). The combination of a low-temperature isotropic (LTI) inner and outer pyrocarbon layers surrounding a strong, stable SiC layer greatly improved manufacturing conditions and the subsequent contamination and defective particle fractions in production fuel elements. In addition, this combination provided improved mechanical strength and a higher degree of solid fission product retention, not known previously with high-temperature isotropic (HTI) BISO coatings. The improved performance of the HEU (Th, U)O{sub 2} TRISO fuel system was successfully demonstrated in three primary areas of development: manufacturing, irradiation testing under normal operating conditions, and accident simulation testing. In terms of demonstrating performance for advanced HTGR applications, the experimental failure statistic from manufacture and irradiation testing are significantly below the coated particle requirements specified for PNP and HHT designs at the time. Covering a range to 1300 C in normal operations and 1600 C in accidents, with burnups to 13% FIMA and fast fluences to 8 x 10{sup 25} n/m{sup 2} (E> 16 fJ), the performance results exceed the design limits on manufacturing and operational requirements for the German HTR-Modul concept, which are 6.5 x 10{sup -5} for manufacturing, 2 x 10{sup -4} for normal operating conditions, and 5 x 10{sup -4

  5. Medium-enriched uranium/thorium fuel cycle parametric studies for the HTGR

    International Nuclear Information System (INIS)

    Operation of HTGRs on proliferation-resistant medium-enriched uranium/thorium fuel cycles is feasible based on the findings of fuel cycle parametric studies conducted for the Department of Energy by General Atomic Company. The analyses performed to evaluate the feasibility and optimization of such fuel cycles are described. Primary variables considered in arriving at optimum designs included cycle length, fuel particle and fuel rod dimensions, the carbon-to-thorium ratio, and the refueling frequency

  6. Introducing advanced thorium-based fuel cycles in SA : an evolutionary approach / Maria Hendrina (Marina) du Toit

    OpenAIRE

    Du Toit, Maria Hendrina

    2013-01-01

    Past experience in several thorium fuelled research- and power reactors provides the basis and history of thorium. The material properties, fertile- and fissile isotope properties as well as the decay chain of thorium are discussed for purposes of evaluating thorium as a source of fuel. The different thorium-based fuel designs for PWR cores are discussed and resulting difficulties and solutions are outlined. The different options for each strategy are compared in terms of ad...

  7. Feasibility study on the thorium fueled boiling water breeder reactor

    International Nuclear Information System (INIS)

    The feasibility of (Th,U)O 2 fueled, boiling water breeder reactor based on conventional BWR technology has been studied. In order to determine the potential use of water cooled thorium reactor as a competitive breeder, this study evaluated criticality, breeding and void reactivity coefficient in response to changes made in MFR and fissile enrichments. The result of the study shows that while using light water as moderator, low moderator to fuel volume ratio (MFR=0.5), it was possible to breed fissile fuel in negative void reactivity condition. However the burnup value was lower than the value of the current LWR. On the other hand, heavy water cooled reactor shows relatively wider feasible breeding region, which lead into possibility of designing a core having better neutronic and economic performance than light water with negative void reactivity coefficient. (authors)

  8. Fuel cycle and waste management. 7. Thorium Nitrate Stockpile Stewardship and Disposition Technical Basis

    International Nuclear Information System (INIS)

    Oak Ridge National Laboratory (ORNL) is performing work for the Defense Logistics Agency (DLA) of the U.S. Department of Defense (DOD) to assist in a future determination of the disposition for thorium nitrate hydrate [Th(NO3)4.5H2O] currently stored at Hammond, Indiana, and Curtis Bay, Maryland. The DLA has ∼3500 tons of ThN contained in 21 000 drums of various configurations. This material has been declared surplus to the needs of the DOD. The ORNL efforts will supply technical input to quantify the potential for use in a thorium fuel cycle and identify characterization requirements and processing requirements consistent with available waste disposition pathways. The Defense National Support Command stores ∼7 million pounds of thorium nitrate crystals (hydrate form) at two depot locations in the United States (75 wt% at the Curtis Bay, Maryland, depot and 25 wt% at the Hammond, Indiana, depot). The managing agency is the DLA. An upgrade evaluation is required to define and control risks and costs associated with long-term management of the thorium nitrate stockpile. Technical studies are underway to determine the most viable options to be compared against continued storage in the present conditions. The generalized alternatives for technical analysis include the following: A. Retain the stockpile in the thorium nitrate form for disposal. B. Retain the stockpile in the thorium nitrate form for long-term storage. C. Process the stockpile to reduce the thorium nitrate to a suitable thorium form for disposal, without preserving chemical purity. D. Process the stockpile to reduce the thorium nitrate to pure thorium oxide for long-term storage. The technical assessment of option results is the focus of this paper. The methodology for analytical characterization is included because strategies are impacted by whether or not the ThN falls into a hazardous waste category. Baseline location and other relevant information are presented, as impact options, from

  9. Some aspects of the thorium fuel cycle in heavy-water-moderated pressure tube reactors

    International Nuclear Information System (INIS)

    The use of thorium fuel cycles in heavy-water-moderated pressure tube (CANDU) reactors will allow much more energy to be extracted from a given amount of fuel than is possible with the present natural uranium cycle. The extent to which various factors affect thorium fuel cycle economics and resource consumption with equilibrium 233U levels in the fuel is considered. Resource consumption in growing nuclear power systems is also considered, and it is shown that considerable savings can be achieved even under conditions of rapid growth. The main elements of the development program necessary to provide the technological base for thorium fuel cycles in CANDU reactors are discussed. (author)

  10. Some aspects of the thorium fuel cycle in heavy-water-moderated pressure tube reactors

    International Nuclear Information System (INIS)

    The use of thorium fuel cycles in heavy-water-moderated pressure tube (CANDU) reactors will allow much more energy to be extracted from a given amount of fuel than is possible with the present natural uranium cycle. The extent to which various factors affect thorium fuel cycle economics and resource consumption with equilibrium 233U levels in the fuel is considered. Resource consumption in growing nuclear power systems is also considered, and it is shown that considerable savings can be achieved even under conditions of rapid growth. The main elements of the development program necessary to provide the technological base for thorium fuel cycles in CANDU reactors are discussed

  11. Investigation of potential utilization for light water reactor spent fuel and thorium fuel in ACR-700

    International Nuclear Information System (INIS)

    The potential utilization of light water reactor (LWR) spent fuel and thorium fuel is a very efficient way for solving spent fuel processing and nuclear fuel shortage problems. Four different mixed fuel types with LWR spent fuel and Th fuel were researched in ACR-700 using SCALE5.1 code system. Compared with the ACR-700 standard fuel, the fuel cycle model 1 and 4 can reach higher burnup. According to the research on the lattice physics of ACR-700 fuel bundle, it is indicated that LWR spent fuel after separation of the fission products is a very prospective fuel in ACR-700 and 232Th can be a preferable fertile isotope if sufficient booster fuel is supplied. (authors)

  12. Simulation on reactor TRIGA Puspati core kinetics fueled with thorium (Th) based fuel element

    Energy Technology Data Exchange (ETDEWEB)

    Mohammed, Abdul Aziz, E-mail: azizM@uniten.edu.my; Rahman, Shaik Mohmmed Haikhal Abdul [Universiti Tenaga Nasional. Jalan Ikram-UNITEN, 43000 Kajang, Selangor (Malaysia); Pauzi, Anas Muhamad, E-mail: anas@uniten.edu.my; Zin, Muhamad Rawi Muhammad; Jamro, Rafhayudi; Idris, Faridah Mohamad [Malaysian Nuclear Agency, Bangi, 43000 Kajang, Selangor (Malaysia)

    2016-01-22

    In confronting global energy requirement and the search for better technologies, there is a real case for widening the range of potential variations in the design of nuclear power plants. Smaller and simpler reactors are attractive, provided they can meet safety and security standards and non-proliferation issues. On fuel cycle aspect, thorium fuel cycles produce much less plutonium and other radioactive transuranic elements than uranium fuel cycles. Although not fissile itself, Th-232 will absorb slow neutrons to produce uranium-233 ({sup 233}U), which is fissile. By introducing Thorium, the numbers of highly enriched uranium fuel element can be reduced while maintaining the core neutronic performance. This paper describes the core kinetic of a small research reactor core like TRIGA fueled with a Th filled fuel element matrix using a general purpose Monte Carlo N-Particle (MCNP) code.

  13. Simulation on reactor TRIGA Puspati core kinetics fueled with thorium (Th) based fuel element

    International Nuclear Information System (INIS)

    In confronting global energy requirement and the search for better technologies, there is a real case for widening the range of potential variations in the design of nuclear power plants. Smaller and simpler reactors are attractive, provided they can meet safety and security standards and non-proliferation issues. On fuel cycle aspect, thorium fuel cycles produce much less plutonium and other radioactive transuranic elements than uranium fuel cycles. Although not fissile itself, Th-232 will absorb slow neutrons to produce uranium-233 (233U), which is fissile. By introducing Thorium, the numbers of highly enriched uranium fuel element can be reduced while maintaining the core neutronic performance. This paper describes the core kinetic of a small research reactor core like TRIGA fueled with a Th filled fuel element matrix using a general purpose Monte Carlo N-Particle (MCNP) code

  14. Simulation on reactor TRIGA Puspati core kinetics fueled with thorium (Th) based fuel element

    Science.gov (United States)

    Mohammed, Abdul Aziz; Pauzi, Anas Muhamad; Rahman, Shaik Mohmmed Haikhal Abdul; Zin, Muhamad Rawi Muhammad; Jamro, Rafhayudi; Idris, Faridah Mohamad

    2016-01-01

    In confronting global energy requirement and the search for better technologies, there is a real case for widening the range of potential variations in the design of nuclear power plants. Smaller and simpler reactors are attractive, provided they can meet safety and security standards and non-proliferation issues. On fuel cycle aspect, thorium fuel cycles produce much less plutonium and other radioactive transuranic elements than uranium fuel cycles. Although not fissile itself, Th-232 will absorb slow neutrons to produce uranium-233 (233U), which is fissile. By introducing Thorium, the numbers of highly enriched uranium fuel element can be reduced while maintaining the core neutronic performance. This paper describes the core kinetic of a small research reactor core like TRIGA fueled with a Th filled fuel element matrix using a general purpose Monte Carlo N-Particle (MCNP) code.

  15. Accelerator molten-salt breeding and thorium fuel cycle

    International Nuclear Information System (INIS)

    The recent efforts at the development of fission energy utilization have not been successful in establishing fully rational technology. A new philosophy should be established on the basis of the following three principles: (1) thorium utilization, (2) molten-salt fuel concept, and (3) separation of fissile-breeding and power-generating functions. Such philosophy is called 'Thorium Molten-Salt Nuclear Energy Synergetics [THORIMS-NES]'. The present report first addresses the establishment of 233U breeding fuel cycle, focusing on major features of the Breeding and Chemical Processing Centers and a small molten-salt power station (called FUJI-II). The development of fissile producing breeders is discussed in relation to accelerator molten-salt breeder (AMSB), impact fusion molten-salt breeder, and inertial-confined fusion hybrid molten-salt breeder. Features of the accelerator molten-salt breeder are described, focusing on technical problems with accelerator breeders (or spallators), design principle of the accelerator molten-salt breeder, selection of molten salt compositions, and nuclear- and reactor-chemical aspects of AMSB. Discussion is also made of further research and development efforts required in the future for AMSB. (N.K.)

  16. Thorium-based fuel cycles: Reassessment of fuel economics and proliferation risk

    International Nuclear Information System (INIS)

    At current consumption and current prices, the proven reserves for natural uranium will last only about 100 years. However, the more abundant thorium, burned in breeder reactors, such as large High Temperature Gas-Cooled Reactors, and followed by chemical reprocessing of the spent fuel, could stretch the 100 years for uranium supply to 15,000 years. Thorium-based fuel cycles are also viewed as more proliferation resistant compared to uranium. However, several barriers to entry caused all countries, except India and Russia, to abandon their short term plans for thorium reactor projects, in favour of uranium/plutonium fuel cycles. In this article, based on the theory of resonance integrals and original analysis of fast fission cross sections, the breeding potential of 232Th is compared to that of 238U. From a review of the literature, the fuel economy of thorium-based fuel cycles is compared to that of natural uranium-based cycles. This is combined with a technical assessment of the proliferation resistance of thorium-based fuel cycles, based on a review of the literature. Natural uranium is currently so cheap that it contributes only about 10% of the cost of nuclear electricity. Chemical reprocessing is also very expensive. Therefore conservation of natural uranium by means of the introduction of thorium into the fuel is not yet cost effective and will only break even once the price of natural uranium were to increase from the current level of about $70/pound yellow cake to above about $200/pound. However, since fuel costs constitutes only a small fraction of the total cost of nuclear electricity, employing reprocessing in a thorium cycle, for the sake of its strategic benefits, may still be a financially viable option. The most important source of the proliferation resistance of 232Th/233U fuel cycles is denaturisation of the 233U in the spent fuel by 232U, for which the highly radioactive decay chain potentially poses a large radiation as well as a detection risk

  17. Thorium-based fuel cycles: Reassessment of fuel economics and proliferation risk

    Energy Technology Data Exchange (ETDEWEB)

    Serfontein, Dawid E., E-mail: Dawid.Serfontein@nwu.ac.za [Senior Lecturer at the School of Mechanical and Nuclear Engineering, North West University (PUK-Campus), PRIVATE BAG X6001, Internal Post Box 360, Potchefstroom 2520 (South Africa); Mulder, Eben J. [Professor at the School of Mechanical and Nuclear Engineering, North West University (South Africa)

    2014-05-01

    At current consumption and current prices, the proven reserves for natural uranium will last only about 100 years. However, the more abundant thorium, burned in breeder reactors, such as large High Temperature Gas-Cooled Reactors, and followed by chemical reprocessing of the spent fuel, could stretch the 100 years for uranium supply to 15,000 years. Thorium-based fuel cycles are also viewed as more proliferation resistant compared to uranium. However, several barriers to entry caused all countries, except India and Russia, to abandon their short term plans for thorium reactor projects, in favour of uranium/plutonium fuel cycles. In this article, based on the theory of resonance integrals and original analysis of fast fission cross sections, the breeding potential of {sup 232}Th is compared to that of {sup 238}U. From a review of the literature, the fuel economy of thorium-based fuel cycles is compared to that of natural uranium-based cycles. This is combined with a technical assessment of the proliferation resistance of thorium-based fuel cycles, based on a review of the literature. Natural uranium is currently so cheap that it contributes only about 10% of the cost of nuclear electricity. Chemical reprocessing is also very expensive. Therefore conservation of natural uranium by means of the introduction of thorium into the fuel is not yet cost effective and will only break even once the price of natural uranium were to increase from the current level of about $70/pound yellow cake to above about $200/pound. However, since fuel costs constitutes only a small fraction of the total cost of nuclear electricity, employing reprocessing in a thorium cycle, for the sake of its strategic benefits, may still be a financially viable option. The most important source of the proliferation resistance of {sup 232}Th/{sup 233}U fuel cycles is denaturisation of the {sup 233}U in the spent fuel by {sup 232}U, for which the highly radioactive decay chain potentially poses a large

  18. Preliminary study on characteristics of equilibrium thorium fuel cycle of BWR

    International Nuclear Information System (INIS)

    One of the main objectives behind the transuranium recycling ideas is not merely to utilize natural resource that is uranium much more efficiently, but to reduce the environmental impact of the radio-toxicity of the nuclear spent fuel. Beside uranium resource, there is thorium which has three times abundance compared to that of uranium which can be utilized as nuclear fuel. On top of that thorium is believed to have less radio-toxicity of spent fuel since its produce smaller amount of higher actinides compared to that of uranium. However, the studies on the thorium utilization in nuclear reactor in particular in light water reactors (LWR) are not performed intensively yet. Therefore, the aim of the present study is to evaluate the characteristics of thorium fuel cycle in LWR, especially boiling water reactor (BWR). To conduct the comprehensive investigations we have employed the equilibrium burnup model (1-3). The equilibrium burnup model is an alternative powerful method since its can handle all possible generated nuclides in any nuclear system. Moreover, this method is a simple time independent method. Hence the equilibrium burnup method could be very useful for evaluating and forecasting the characteristics of any nuclear fuel cycle, even the strange one, e.g. all nuclides are confined in the reactor1). We have employed 1368 nuclides in the equilibrium burnup calculation where 129 of them are heavy metals (HMs). This burnup code then is coupled with SRAC cell calculation code by using PIJ module to compose an equilibrium-cell burnup code. For cell calculation, 26 HMs, 66 fission products (FPs) and one pseudo FP have been utilized. The JENDL 3.2 library has been used in this study. References: 1. A. Waris and H. Sekimoto, 'Characteristics of several equilibrium fuel cycles of PWR', J. Nucl. Sci. Technol., 38, p.517-526, 2001 2. A. Waris, H. Sekimoto, and G. Kastchiev, Influence of Moderator-to-Fuel Volume Ratio on Pu and MA Recycling in Equilibrium Fuel Cycles of

  19. Optimisation Studies of Accelerator Driven Fertile to Fissile Conversion Rates in Thorium Fuel Cycle

    OpenAIRE

    Bungau, Cristian; Barlow, Roger; Cywinski, R.

    2012-01-01

    The need for proliferation-resistance, longer fuel cycles, higher burn up and improvedwaste form characteristics has led to a renewed worldwide interest in thorium-based fuels and fuel cycles. In this paper the GEANT4 Monte Carlo code has been used to simulate the Thorium-Uranium fuel cycle. The accelerator driven fertile to fissile conversion rates have been calculated for various geometries. Several new classes have been added by the authors to the GEANT4 simulation ...

  20. Feasibility assessment of the once-through thorium fuel cycle for the PTVM LWR concept

    International Nuclear Information System (INIS)

    Highlights: • The PTVM LWR is an innovation reactor concept operating in a “breed & burn” mode. • An advanced once-through thorium fuel cycle for the PTVM LWR concept is proposed. • The PTVM LWR concept makes use of a seed-blanket geometry. • A novel fuel management scheme based on two separate fuel flow routes is analyzed. • The analysis indicates a potential for utilizing the fuel in an efficient manner. - Abstract: This paper investigates the feasibility of a once-through thorium fuel cycle for the novel reactor-design concept named the pressure tube light water reactor with variable moderator control (PTVM LWR). The PTVM LWR operates in a “breed & burn” mode, which makes it an attractive system for utilizing thorium fuel in a once-through mode. The “breed & burn” mode can emphasize the in situ generation as well as incineration of 233U, which are the basic foundations of the once-through thorium fuel cycle. The PTVM LWR concept makes use of a seed–blanket geometry, whereby the core is divided into separated regions of thorium-based fuel channel assemblies (blanket) and low-enriched uranium (LEU) based fuel channel assemblies (seed). A novel fuel in-core management scheme based on two separate fuel flow routes (i.e., seed route and blanket route) is proposed and analyzed. Neutronic performance analysis indicates that the proposed novel fuel in-core management scheme has the potential to utilize both LEU- and thorium-based fuel in an efficient manner. The once-through thorium cycle, presented and discussed in this paper, provide interesting research leads and can serve as a bridge between current LEU-based fuel cycles and a thorium fuel cycle based on recycling of 233U

  1. Improving burnup performance of fast sodium cooled reactor by utilizing thorium based fuels

    International Nuclear Information System (INIS)

    To study the improvement of fuel burnup for fast reactors, thorium based fuels are investigated. In order to ensure the projected expansion of nuclear power is achieved in conjunction with reduced risk of nuclear weapons proliferation, new conventional sources of fuel will have to be made available. Thorium fuel cycles have many incentives such as the reduction of plutonium generation and consumption of LWR actinides, the provision of high performance burnup, and the conservation of 235U resources. This work examined the burnup reactivity loss and depletion analysis of thorium versus uranium based metal fuels. When compared the thorium based metallic fuel outperformed uranium based fuel with respect to higher actinide burnup and higher depletion rate of plutonium isotopes. (authors)

  2. INR Recent Contributions to Thorium-Based Fuel Using in CANDU Reactors

    International Nuclear Information System (INIS)

    The paper summarizes INR Pitesti contributions and latest developments to the Thorium-based fuel (TF) using in present CANDU nuclear reactors. Earlier studies performed in INR Pitesti revealed the CANDU design potential to use Recovered Uranium (RU) and Slightly Enriched Uranium (SEU) as alternative fuels in PHWRs. In this paper, we performed both lattice and CANDU core calculations using TF, revealing the main neutron physics parameters of interest: k-infinity, coolant void reactivity (CVR), channel and bundle power distributions over a CANDU 6 reactor core similar to that of Cernavoda, Unit 1. We modelled the so called Once Through Thorium (OTT) fuel cycle, using the 3D finite-differences DIREN code, developed in INR. The INR flexible SEU-43 bundle design was the candidate for TF carrying. Preliminary analysis regarding TF burning in CANDU reactors has been performed using the finite differences 3D code DIREN. TFs showed safety features improvement regarding lower CVRs in the case of fresh fuel use. Improvements added to the INR ELESIMTORIU- 1 computer code give the possibility to fairly simulate irradiation experiments in INR TRIGA research reactor. Efforts are still needed in order to get better accuracy and agreement of simulations to the experimental results. (author)

  3. Role of Thorium to Supplement Fuel Cycles of Future Nuclear Energy Systems

    International Nuclear Information System (INIS)

    The investigation of the thorium fuel cycle (ThFC) is a collaborative INPRO (International Project on Innovative Nuclear Reactors and Fuel Cycles) activity within its main area on global vision on sustainable nuclear energy for the 21st century. The current publication reports on the sustainability of nuclear power by re-examining the potential of thorium-based fuel cycles to support future large scale deployment of nuclear energy systems by increasing the availability of nuclear material. Special attention is paid to the thorium fuel cycle from the point of view of economics and proliferation resistance.

  4. Determination of uranium in thorium matrix- a novel approach to quality control in nuclear fuel cycle

    International Nuclear Information System (INIS)

    In view of potential role of thorium in the future nuclear programme, research and development work in various aspects of thorium fuel cycle has been undertaken. Besides, the recent interest in thorium utilisation in Pressurised Heavy Water Reactors (PHWRs) necessitates monitoring of its purity with respect to a number of metallics which are of significance to its performance. Prominent among these metals and equally difficult to determine at trace level is uranium

  5. Inhalation radiotoxicity of irradiated thorium as a heavy water reactor fuel

    International Nuclear Information System (INIS)

    The online refueling capability of Heavy Water Reactors (HWRs), and their good neutron economy, allows a relatively high amount of neutron absorption in breeding materials to occur during normal fuel irradiation. This characteristic makes HWRs uniquely suited to the extraction of energy from thorium. In Canada, the toxicity and radiological protection methods dealing with personnel exposure to natural uranium (NU) spent fuel (SF) are well-established, but the corresponding methods for irradiated thorium fuel are not well known. This study uses software to compare the activity and toxicity of irradiated thorium fuel ('thorium SF') against those of NU. Thorium elements, contained in the inner eight elements of a heterogeneous high-burnup bundle having LEU (Low-enriched uranium) in the outer 35 elements, achieve a similar burnup to NU SF during its residence in a reactor, and the radiotoxicity due to fission products was found to be similar. However, due to the creation of such inhalation hazards as U-232 and Th-228, the radiotoxicity of thorium SF was almost double that of NU SF after sufficient time has passed for the decay of shorter-lived fission products. Current radio-protection methods for NU SF exposure are likely inadequate to estimate the internal dose to personnel to thorium SF, and an analysis of thorium in fecal samples is recommended to assess the internal dose from exposure to this fuel. (authors)

  6. ALTERNATIVE FUELS FOR DIESEL ENGINES

    Directory of Open Access Journals (Sweden)

    Jacek Caban

    2013-12-01

    Full Text Available This paper presents the development and genesis of the use of alternative fuels in internal combustion ignition engines. Based on the analysis of the literature, this article shows various alternative fuels used in Poland and all over the world. Furthermore, this article describes the research directions for alternative fuels use in road transport powered by diesel engines.

  7. ALTERNATIVE FUELS FOR DIESEL ENGINES

    OpenAIRE

    Jacek Caban; Agata Gniecka; Lukáš Holeša

    2013-01-01

    This paper presents the development and genesis of the use of alternative fuels in internal combustion ignition engines. Based on the analysis of the literature, this article shows various alternative fuels used in Poland and all over the world. Furthermore, this article describes the research directions for alternative fuels use in road transport powered by diesel engines.

  8. Thermal Hydraulic Analysis Of Thorium-Based Annular Fuel Assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Han, Kyu Hyun [Korea Institute of Nuclear Safety, 19, Guseong-dong, Yuseong-gu, Daejeon, 305-338 (Korea, Republic of)

    2008-07-01

    Thermal hydraulic characteristics of thorium-based fuel assemblies loaded with annular seed pins have been analyzed using AMAP combined with MATRA, and compared with those of the existing thorium-based assemblies. MATRA and AMAP showed good agreements for the pressure drops at the internal sub-channels. The pressure drop generally increased in the cases of the assemblies loaded with annular seed pins due to the larger wetted perimeter, but an exception existed. In the inner sub-channels of the seed pins, mass fluxes were high due to the grid form losses in the outer sub-channels. About 43% of the heat generated from the seed pin flowed into the inner sub-channel and the rest into the outer sub-channel, which implies the inner to outer wall heat flux ratio was approximately 1.2. The maximum temperatures of the annular seed pins were slightly above 500 deg. C. The MDNBRs of the assemblies loaded with annular seed pins were higher than those of the existing assemblies. Due to the fact that inter-channel mixing cannot occur in the inner sub-channels, temperatures and enthalpies were higher in the inner sub-channels. (author)

  9. Thermal Hydraulic Analysis Of Thorium-Based Annular Fuel Assemblies

    International Nuclear Information System (INIS)

    Thermal hydraulic characteristics of thorium-based fuel assemblies loaded with annular seed pins have been analyzed using AMAP combined with MATRA, and compared with those of the existing thorium-based assemblies. MATRA and AMAP showed good agreements for the pressure drops at the internal sub-channels. The pressure drop generally increased in the cases of the assemblies loaded with annular seed pins due to the larger wetted perimeter, but an exception existed. In the inner sub-channels of the seed pins, mass fluxes were high due to the grid form losses in the outer sub-channels. About 43% of the heat generated from the seed pin flowed into the inner sub-channel and the rest into the outer sub-channel, which implies the inner to outer wall heat flux ratio was approximately 1.2. The maximum temperatures of the annular seed pins were slightly above 500 deg. C. The MDNBRs of the assemblies loaded with annular seed pins were higher than those of the existing assemblies. Due to the fact that inter-channel mixing cannot occur in the inner sub-channels, temperatures and enthalpies were higher in the inner sub-channels. (author)

  10. A competitive thorium fuel cycle for pressurized water reactors of current technology

    International Nuclear Information System (INIS)

    Two important issues may influence the development and public acceptance of the nuclear power worldwide: a reduction of proliferation potential and spent fuel disposal requirements of the nuclear fuel cycle. Both problems may be addressed effectively by replacement of uranium by thorium fertile part of the fuel. A practical and competitive fuel design to satisfy the described design objectives and constraints may be achieved by seed-blanket core, proposed by A. Radkowsky and implemented in Shippingport reactors. The main idea is to separate spatially the uranium part of the core (seed) from the thorium part of the core (blanket), and thus allow two separate fuel management routes for uranium and thorium parts of the fuel. The uranium part (seed) is optimized to supply neutrons to the subcritical thorium blanket. The blanket is designed to generate and bum insitu 233U. (author)

  11. Alternate fuels; Combustibles alternos

    Energy Technology Data Exchange (ETDEWEB)

    Romero Paredes R, Hernando; Ambriz G, Juan Jose [Universidad Autonoma Metropolitana. Iztapalapa (Mexico)

    2003-07-01

    In the definition and description of alternate fuels we must center ourselves in those technological alternatives that allow to obtain compounds that differ from the traditional ones, in their forms to be obtained. In this article it is tried to give an overview of alternate fuels to the conventional derivatives of petroleum and that allow to have a clear idea on the tendencies of modern investigation and the technological developments that can be implemented in the short term. It is not pretended to include all the tendencies and developments of the present world, but those that can hit in a relatively short term, in accordance with agreed with the average life of conventional fuels. Nevertheless, most of the conversion principles are applicable to the spectrum of carbonaceous or cellulosic materials which are in nature, are cultivated or wastes of organic origin. Thus one will approach them in a successive way, the physical, chemical and biological conversions that can take place in a production process of an alternate fuel or the same direct use of the fuel such as burning the sweepings derived from the forests. [Spanish] En la definicion y descripcion de combustibles alternos nos debemos centrar en aquellas alternativas tecnologicas que permitan obtener compuestos que difieren de los tradicionales, al menos en sus formas de ser obtenidos. En este articulo se pretende dar un panorama de los combustibles alternos a los convencionales derivados del petroleo y que permita tener una idea clara sobre las tendencias de la investigacion moderna y los desarrollos tecnologicos que puedan ser implementados en el corto plazo. No se pretende abarcar todas las tendencias y desarrollos del mundo actual, sino aquellas que pueden impactar en un plazo relativamente corto, acordes con la vida media de los combustibles convencionales. Sin embargo, la mayor parte de los principios de conversion son aplicables al espectro de materiales carbonaceos o celulosicos los cuales se

  12. Design and evaluation of a thorium fueled reactor with seed-blanket assembly configuration

    International Nuclear Information System (INIS)

    Recently, thorium fuel cycle is receiving increasing attention as one of possible ways to solve the problems of existing reactor design. In particular, a competitive thorium fuel cycle for pressurized water reactors of current technology, Radkowsky Thorium Reactor (RTR), was suggested by Radkowsky, et al. Main design concept of RTR is to replace the fuel assemblies of existing reactors with new thorium fueled assemblies with seed-blanket configuration. Except for the use of Seed-Blanket Units (SBUs), RTR has almost the same hardware components with existing PWR technology. With minor modification, RTR concepts may be adopted to PWR. In this thesis, we designed a thorium fueled reactor according to the design features of RTR and carried out the assessment of its overall performance. For numerical estimation, we used the cell code system HELIOS and the 2-group diffusion nodal code system AFEN. The link of these two code systems was done for depletion calculation. To compare its performance with existing PWRs, the ABB/CE type SYSTEM 80+ core was also modeled and calculated. From the preliminary results of performance analysis of an RTR-type thorium reactor, and comparison with the ABB/CE type reactor, we could ascertain some advantages and problems. Although some technical problems still remain, i.e., the need of extensive use of burnable absorbers and other thermo-mechanical problems, we conclude that RTR-type thorium reactor may is one of the effective ways to solve the two main problems of existing nuclear technology, i.e., possible diversion of the spent fuel for weapons and the storage and disposal of the spent fuel (discharged fuel is less in amount and poor in fissile plutonium quality). From RTR-type thorium fuel cycle, we can also achieve economical benefits because it requires much less uranium and thorium than existing PWR to produce the same amount of energy

  13. BIODIESEL – ALTERNATIVE FUEL

    Directory of Open Access Journals (Sweden)

    Darko Kiš

    2006-06-01

    Full Text Available A limited quantity of oil, the purchase of which also involves major expenses has become an important factor for intensive search and use of alternative fuels. Biodiesel is used in diesel engines, and is manufactured from vegetable oils, animal fats and recycled edible oils. The production and use of biodiesel are very important not only because of its economic and strategic connotations but also because of its environmental advantages. Favourable conditions in Croatia give good opportunities for a self-sufficient oil rape production, possibility for its intensification and employment of a number of people in both the agricultural production and biodiesel production plants. This paper presents a survey of the biodiesel fuel production, the characteristics and impacts it has on the biodiesel engine features as well as its impact on the environment.

  14. Critical review of analytical techniques for safeguarding the thorium-uranium fuel cycle

    Energy Technology Data Exchange (ETDEWEB)

    Hakkila, E.A.

    1978-10-01

    Conventional analytical methods applicable to the determination of thorium, uranium, and plutonium in feed, product, and waste streams from reprocessing thorium-based nuclear reactor fuels are reviewed. Separations methods of interest for these analyses are discussed. Recommendations concerning the applicability of various techniques to reprocessing samples are included. 15 tables, 218 references.

  15. Thorium Energy Futures

    Energy Technology Data Exchange (ETDEWEB)

    Peggs, Stephen; Roser, Thomas; Parks, G; Lindroos, Mats; Seviour, Rebecca; Henderson, Stuart; Barlow, R; Cywinski, R; Biarrote, J -L; Norlin, A; Ashley, V; Ashworth, R; Hutton, Andrew; Owen, H; McIntyre, Peter

    2012-07-01

    The potential for thorium as an alternative or supplement to uranium in fission power generation has long been recognised, and several reactors, of various types, have already operated using thorium-based fuels. Accelerator Driven Subcritical (ADS) systems have benefits and drawbacks when compared to conventional critical thorium reactors, for both solid and molten salt fuels. None of the four options - liquid or solid, with or without an accelerator - can yet be rated as better or worse than the other three, given today's knowledge. We outline the research that will be necessary to lead to an informed choice.

  16. Analysis of integral experiment for thorium fuel cycle at Kyoto University Critical Assembly

    International Nuclear Information System (INIS)

    To measure integral neutronics characteristics of thorium loaded core, critical experiments had been carried out at Kyoto University Critical Assembly (KUCA). The critical experiments were performed with various neutron spectra and thorium inventories. The thorium loaded core has two regions which are a test zone and a driver fuel zone. The test zone consists of thorium plates and graphite plates. In order to change the neutron spectrum of the experimental neutron field systematically, the graphite/Th-232 ratio at the test zone had been systematically varied by changing the combination of the thorium plates and the graphite plates in a unit cell. In this study, the criticalities of thorium loaded core were analyzed by MVP2.0 with JENDL-4.0, JENDL-3.3. In addition, sensitivity analyses were performed by SAGEP code and uncertainties of the numerical results were evaluated by using cross section covariance matrix. (author)

  17. NASA Alternative Aviation Fuel Research

    Science.gov (United States)

    Anderson, B. E.; Beyersdorf, A. J.; Thornhill, K. L., II; Moore, R.; Shook, M.; Winstead, E.; Ziemba, L. D.; Crumeyrolle, S.

    2015-12-01

    We present an overview of research conducted by NASA Aeronautics Research Mission Directorate to evaluate the performance and emissions of "drop-in" alternative jet fuels, highlighting experiment design and results from the Alternative Aviation Fuel Experiments (AAFEX-I & -II) and Alternative Fuel-Effects on Contrails and Cruise Emissions flight series (ACCESS-I & II). These projects included almost 100 hours of sampling exhaust emissions from the NASA DC-8 aircraft in both ground and airborne operation and at idle to takeoff thrust settings. Tested fuels included Fischer-Tropsch (FT) synthetic kerosenes manufactured from coal and natural-gas feedstocks; Hydro-treated Esters and Fatty-Acids (HEFA) fuels made from beef-tallow and camelina-plant oil; and 50:50 blends of these alternative fuels with Jet A. Experiments were also conducted with FT and Jet A fuels doped with tetrahydrothiophene to examine the effects of fuel sulfur on volatile aerosol and contrail formation and microphysical properties. Results indicate that although the absence of aromatic compounds in the alternative fuels caused DC-8 fuel-system leaks, the fuels did not compromise engine performance or combustion efficiency. And whereas the alternative fuels produced only slightly different gas-phase emissions, dramatic reductions in non-volatile particulate matter (nvPM) emissions were observed when burning the pure alternative fuels, particularly at low thrust settings where particle number and mass emissions were an order of magnitude lower than measured from standard jet fuel combustion; 50:50 blends of Jet A and alternative fuels typically reduced nvPM emissions by ~50% across all thrust settings. Alternative fuels with the highest hydrogen content produced the greatest nvPM reductions. For Jet A and fuel blends, nvPM emissions were positively correlated with fuel aromatic and naphthalene content. Fuel sulfur content regulated nucleation mode aerosol number and mass concentrations within aging

  18. Neutronic evaluation of thorium and reprocessed fuels by GANEX and UREX+ in ADS

    Energy Technology Data Exchange (ETDEWEB)

    Barros, Graiciany, E-mail: graiciany.barros@cnen.gov.br [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil); Velasquez, Carlos E.; Pereira, Claubia; Veloso, Maria Auxiliadora F.; Costa, Antonella L., E-mail: claubia@nuclear.ufmg.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Escola de Engenharia. Departamento de Engenharia Nuclear

    2015-07-01

    A conceptual design of accelerator driven systems (ADS) that utilize thorium and reprocessed fuel in order to produce {sup 233}U and to transmute high radiotoxicity isotopes in spent nuclear fuel has been proposed. The use of thorium and reprocessed fuel in an ADS is one of the clean, safe, and economical solutions for the problem of nuclear waste. In this study, the aim was to compare the neutronic behavior of the core using spent fuel reprocessed by GANEX (Group ActiNide EXtraction) and UREX+ (Uranium Extraction), both spiked with thorium. The simulated design was a cylinder fuelled with a hexagonal lattice with 156 fuel rods. One of the studied fuels was a mixture based upon Pu-MA, removed from PWR-spent fuel, theoretically reprocessed by GANEX reprocessing and spiked with 82% of thorium. The other fuel was a reprocessed fuel obtained theoretically from UREX+ (Uranium Extraction) process and spiked with 82% of thorium. Monteburns 2.0 (MCNP5/ORIGEN 2.1) code was used to simulate the neutronic aspects of the fuels. The multiplication factors, the neutron spectra, and the nuclear fuel evolution were analyzed during 10 years of burn-up. The results allowed comparing the two reprocessing techniques, the {sup 233}U production and the reduction in the amount of high radiotoxicity isotopes of these fuels. (author)

  19. Neutronic evaluation of thorium and reprocessed fuels by GANEX and UREX+ in ADS

    International Nuclear Information System (INIS)

    A conceptual design of accelerator driven systems (ADS) that utilize thorium and reprocessed fuel in order to produce 233U and to transmute high radiotoxicity isotopes in spent nuclear fuel has been proposed. The use of thorium and reprocessed fuel in an ADS is one of the clean, safe, and economical solutions for the problem of nuclear waste. In this study, the aim was to compare the neutronic behavior of the core using spent fuel reprocessed by GANEX (Group ActiNide EXtraction) and UREX+ (Uranium Extraction), both spiked with thorium. The simulated design was a cylinder fuelled with a hexagonal lattice with 156 fuel rods. One of the studied fuels was a mixture based upon Pu-MA, removed from PWR-spent fuel, theoretically reprocessed by GANEX reprocessing and spiked with 82% of thorium. The other fuel was a reprocessed fuel obtained theoretically from UREX+ (Uranium Extraction) process and spiked with 82% of thorium. Monteburns 2.0 (MCNP5/ORIGEN 2.1) code was used to simulate the neutronic aspects of the fuels. The multiplication factors, the neutron spectra, and the nuclear fuel evolution were analyzed during 10 years of burn-up. The results allowed comparing the two reprocessing techniques, the 233U production and the reduction in the amount of high radiotoxicity isotopes of these fuels. (author)

  20. Spent-fuel-storage alternatives

    International Nuclear Information System (INIS)

    The Spent Fuel Storage Alternatives meeting was a technical forum in which 37 experts from 12 states discussed storage alternatives that are available or are under development. The subject matter was divided into the following five areas: techniques for increasing fuel storage density; dry storage of spent fuel; fuel characterization and conditioning; fuel storage operating experience; and storage and transport economics. Nineteen of the 21 papers which were presented at this meeting are included in this Proceedings. These have been abstracted and indexed

  1. Irradiation performance of thorium oxide based coated particle fuels

    International Nuclear Information System (INIS)

    BISO coated ThO2 particles as fertile fuel and BISO or TRISO coated (Th, U)O2 particles as fissile fuel for a High-temperature Gas-cooled Reactor (HTGR) were irradiated to investigate particle performances in loosely-packed condition of two capsules in JRR-2 and one capsule in JMTR. Irradiation of these coated particles was achieved to a maximum fast neutron fluence of 2.22 x 1021 neutrons/cm2 (E > 0.18 MeV) and a maximum thermal neutron fluence of 1.35 x 1021 neutrons/cm2 at temperatures of 770 to 1225 deg C. And a maximum burnup of fissile particles was 2.42 % FIMA. It was found in the post-irradiation examinations that the coated particles were intact except a little of the BISO coated fissile particles, and the thorium oxide based coated particles performed well under the irradiation conditions. The data were also taken on the fission product behavior released from the fuel kernels during the irradiation. And density of the outer LTIPyC (OPyC) increased as increasing the fluence of fast neutron. As a result of the densification of the OPyC, the crushing strength of the BISO coated particles increased, otherwise the TRISO coated particles decreased. (author)

  2. Alternative Fuels in Cement Production

    DEFF Research Database (Denmark)

    Larsen, Morten Boberg

    The substitution of alternative for fossil fuels in cement production has increased significantly in the last decade. Of these new alternative fuels, solid state fuels presently account for the largest part, and in particular, meat and bone meal, plastics and tyre derived fuels (TDF) accounted for...... the most significant alternative fuel energy contributors in the German cement industry. Solid alternative fuels are typically high in volatile content and they may differ significantly in physical and chemical properties compared to traditional solid fossil fuels. From the process point of view......, considering a modern kiln system for cement production, the use of alternative fuels mainly influences 1) kiln process stability (may accelerate build up of blockages preventing gas and/or solids flow), 2) cement clinker quality, 3) emissions, and 4) decreased production capacity. Kiln process stability in...

  3. Consultancy on 'Implementing thorium in nuclear reactor fuel cycles: Potential benefits and challenges'. Working material

    International Nuclear Information System (INIS)

    The objective of this consultancy (CS) was to bring together experts from the MS to discuss R and D developments in the study of thorium fuel cycles and to identify MS needs in support of national activities in this area. The CS was also meant to define an appropriate IAEA response to these needs, e.g., recommend topics for information exchange and collaborative R andD activities to be implemented in a planned CRP. Presentations were made on past thorium-fuel-cycle activities at IAEA, and on R and D activities in Canada, India and the Russian Federation. Following these presentations and further discussions on topics of importance in thorium based fuel cycles, the CS arrived at a proposal for a new CRP entitled 'The Comparative Assessment of the Fuel-Cycle Aspects of Various Thorium-Based Reactor Concepts'. The CRP should be based on a unified systematic approach for a comparative assessment of the various designs for utilizing thorium fuel, and their potential benefits as compared to uranium-plutonium fuelled systems. The CS recommended a list of fuel-cycle performance parameters to be considered in the CRP for the above purpose. Finally, the CS proposed a plan of action for the initiation of the CRP by the Scientific Secretary. The meeting was very much appreciated by the participants and was a good opportunity to exchange information on research activities and methods, and discuss potential challenges to and solutions for the implementation of thorium fuel cycles. (author)

  4. The evolutionary adoption of thorium beginning with its application in niche LWR fuels

    International Nuclear Information System (INIS)

    Since the inception of nuclear energy, the use of thorium as a nuclear fuel has been envisioned. Thorium boasts benefits, however, drawbacks which are both economic and technical including its the lack of a naturally occurring fissile isotope implies that its utility is inherently more difficult. The implementation of thorium as a nuclear fuel requires that it must provide sound technical advantages in combination with attractive economics as compared to standard uranium fuel. Revolutionary thorium concepts such as molten salt reactors and accelerator driven systems may provide theoretical merit, however, their exotic nature and associated technical challenges label them as long-term solutions at best. A near-to-medium term solution for thorium must be based on an evolutionary approach utilizing light/heavy water reactor platforms. While thorium does not provide a near-to-medium term complete replacement of uranium, it does provide substantial benefit within niche applications. To license and bring to market these niche fuels, Thor Energy and an international consortium of entities (including: Fortum, KAERI, Westinghouse, NNL, ITU, IFE, and a few other minor entities) have initiated a fuel development and irradiation test program to characterize the performance of these thoria-containing fuels. (author)

  5. Innovative once-through thorium fuel cycle for the PTVM LWR concept

    International Nuclear Information System (INIS)

    An advanced once-through thorium fuel cycle for the innovative reactor concept, termed the pressure tube light water reactor with variable moderator control (PTVM LWR), is proposed. The PTVM LWR makes use of a seed-blanket geometry, whereby the core is divided into separated regions of thorium fuel channel assemblies (blanket) and low-enriched uranium fuel channel assemblies (seed). A novel fuel management scheme based on two separate fuel flow routes (i.e., seed route and blanket route) is proposed and analyzed. Neutronic analysis indicates that the novel scheme has the potential to utilize both seed and blanket in an efficient manner. (author)

  6. IAEA activities in the area of thorium based nuclear fuel cycles

    International Nuclear Information System (INIS)

    In the framework of IAEA activities Implementing Thorium in Nuclear Fuel Cycles is one of the challenging topics. Incentives for Th-based fuel cycles (vs. U-Pu cycles) are: 233-U breeding capability due to its higher neutron yields in thermal and epithermal regions in Th-233-U cycle; Large Th deposits in some countries; Potentials for fuel cycle cost reduction, 235-U enrichment reduction, safer reactor operation due to lower excess reactivity requirements, safer and more reliable ThO2 fuel at high burnup, potential benefits for reducing Pu production and higher actinides. Disadvantages for Th-based fuel cycles (vs. U-Pu cycles) are: More difficult fuel handling due to its stronger gamma radiation level (228-Tl: strong gamma emitter) - preferable for nonproliferation, more complicated fuel cycle mechanism, longer spent fuel cooling due to higher residual heat, potential difficulties in down stream spent fuel reprocessing. 'New' potential benefits for reducing Pu production and higher actinides are emerging. Coordinated Research Projects (CRPs) 'Potential of Thorium Based Fuel Cycles to Constrain Plutonium and to Reduce Long Lived Waste Toxicity' and 'Use of Thorium Based Fuel Cycles in Accelerator Driven Systems to Incinerate Plutonium and to Reduce Long-term Waste Toxicities' were completed. The following were published: assessment of thermo physical and thermo- hydraulic characteristics of lead, lead-bismuth, and sodium coolants for fast reactors (IAEA TECDOC-1289); Thorium fuel utilization: Options and trends (IAEA TECDOC-1319); Power Reactor and Sub-critical Blanket Systems with Lead and Lead-Bismuth as Coolant and/or Target Material (IAEA TECDOC-1348) Potential of thorium based fuel cycles to constrain plutonium and reduce long lived waste toxicity (IAEA TECDOC-1349). 35th and 36th TWG-FR Meetings recommended to convene a Consultancy to recommend topics for a CRP at investigating the potential benefits of Thorium fuels

  7. Characterization of radiation sources from the fuel cycle. Applications to the thorium fuel cycle: 232U production in solid fuels

    International Nuclear Information System (INIS)

    The thorium cycle is a good candidate for replacing the current U/Pu cycle since the fissile nucleus of the cycle, 233U, has neutronic properties favourable to a much better regeneration of fissile material in thermal reactors. Moreover, the production of minor actinides is significantly reduced. However, the use of Thorium is only viable if the spent fuel is reprocessed to recover the fissile 233U that does not exist in nature. This reprocessing will involve a heavy industrial infrastructure, particularly since thorium based spent fuel contains small quantities of 232U that is the mother of the hard gamma emitter (208Tl) of 2.6 MeV. The goal of this thesis is, firstly, to study the parameters related to the synthesis of 232U in several kind of fuels and reactors. In a second part, the thesis focuses on the impact on radioprotection of the back end of the fuel in case of switching from the current uranium (U/Pu) cycle to the thorium (Th/U) cycle. For this last purpose, CHARS (Characterization of Radioactive Sources) was developed during this thesis. This code, validated by several benchmarks, handles the calculation of radiation sources in all aspects of the fuel cycle. (author)

  8. Neutronic behavior of Thorium based fuel cycles in a pebble bed reactor

    International Nuclear Information System (INIS)

    Thorium is a potentially valuable energy source since it is about three to four times as abundant as Uranium. It is also a widely distributed natural resource readily accessible in many countries. Therefore, Thorium fuels can complement Uranium fuels and ensure long term sustainability of nuclear power. This paper shows the main advantages of the use of a Pebble Bed critical nuclear reactor using a variety of fuel cycles with Thorium (Th+U233, Th+Pu239 and Th+U). the parameters related to the neutronic behavior like deep burn, nuclear fuel breeding, Minor Actinide stockpile, power density profiles and other are used to compare the fuel cycles. also a thermo mechanical study of the irradiated TRISO fuel particle is presented. (Author)

  9. Accuracy of thorium cross section of JENDL-4.0 library in thorium based fuel core evaluation

    International Nuclear Information System (INIS)

    Highlights: ► Critical experiments on Th core were conducted to verify the accuracy of Th232 cross section of JENDL-4.0 library. ► Calculations are found to overestimate effective multiplication factor about (0.90 ± 0.01–0.99 ± 0.01)%. ► Comparison between measured and calculated Th sample worth reassures Th232 capture underestimation of JENDL-4.0 library. ► Th capture cross section is needed to be adjusted at thermal energy range to provide more reliable evaluation. - Abstract: Considering the importance of thorium data and concerning about the accuracy of Th232 cross section library, a series of experiments on thorium critical core with different neutron spectra has been implemented at Kyoto University Critical Assembly (KUCA). Reactivity worth of control rod and thorium sample was measured after the cores experimentally achieved critical state. In order to verify the accuracy of thorium cross section library, calculations of effective multiplication factor, control rod worth, reactivity worth of Th plates for the same core configurations were done by MVP code (Nagaya et al., 2005) using JENDL-4.0 library (Shibata et al., 2011). From the comparison between the measured and calculated results, the calculations are found to overestimate effective multiplication factor about (0.90 ± 0.01–0.99 ± 0.01)%. By comparing the measured Th sample worth with the calculated one, Th capture underestimation is reassured. Sensitive study on reactivity worth evaluation was conducted and it suggests that Th capture cross section is needed to be adjusted at thermal energy range to provide more reliable evaluation for thorium based fuel core design and safety calculation

  10. Spent-fuel-storage alternatives

    Energy Technology Data Exchange (ETDEWEB)

    1980-01-01

    The Spent Fuel Storage Alternatives meeting was a technical forum in which 37 experts from 12 states discussed storage alternatives that are available or are under development. The subject matter was divided into the following five areas: techniques for increasing fuel storage density; dry storage of spent fuel; fuel characterization and conditioning; fuel storage operating experience; and storage and transport economics. Nineteen of the 21 papers which were presented at this meeting are included in this Proceedings. These have been abstracted and indexed. (ATT)

  11. Feasibility Study on AFR-100 Fuel Conversion from Uranium-based Fuel to Thorium-based Fuel

    International Nuclear Information System (INIS)

    The feasibility study of converting a fast reactor from uranium-based fuel to thorium-based fuel was studied using the 100 MWe Advanced Fast Reactor (AFR-100). Several fuel conversion scenarios were envisioned in this study. The first scenario is a progressive fuel conversion without fissile support. It consists of progressively replacing the burnt uranium-based fuel with pure thorium-based fuel without fissile material addition. This was found to be impractical because the low excess reactivity of the uranium-fuelled AFR-100 core, resulting in an extremely short cycle length even when only a few assemblies are replaced. A second scenario consists in operating the reference LEU fuelled AFR-100 core for 24 years and then replacing one fuel batch out of four every 7.04 years with thorium-based fuel mixed with transuranics. The transuranics weight fraction required during the transition period is identical to that required at equilibrium and is equal to 18.6%. The original uranium-based fuel is discharged with an average burnup of 120 GWd/t and the Th-TRU fuel with an average burnup of 101 GWd/t. The thermal-hydraulic and passive safety performances of this core are similar to those of the reference AFR-100 design. However, Th-TRU fuel fabrication and performance needs to be demonstrated and TRU separation from the LWR used nuclear fuel is necessary. The third scenario proposed consists of replacing the whole AFR-100 core with fuel assemblies made of several thorium and 20% enriched LEU layers. The mode of operation is similar to that of the reference AFR-100 core with the exception of the cycle length which needs to be reduced from 30 to 18 years. The average LEU and thorium discharge burnups are 79 GWd/t and 23 GWd/t, respectively. The major benefit of this approach is the improved inherent safety of the reactor due to the reduced coolant void worth. (author)

  12. Flowchart evaluations of irradiated fuel treatment process of low burnup thorium

    International Nuclear Information System (INIS)

    A literature survey has been carried out, on some versions of the acid-thorex process. Flowsheets of the different parts of the process were evaluated with mixer-settlers experiments. A low burnup thorium fuel (mass ratio Th/U∼100/1), proposed for Brazilian fast breeder reactor initial program, was considered. The behaviour of some fission products was studied by irradiated tracers techniques. Modifications in some of the process parameters were necessary to achieve low losses of 233U and 232U and 232Th. A modified acid-thorex process flowsheet, evaluated in a complete operational cycle, for the treatment of low burnup thorium fuels, is presented. High decontamination factors of thorium in uranium, with reasonable decontamination of uranium in thorium, were achieved. (author)

  13. Resources of thorium toward alternatives power plant in Indonesia: a concept of implementation

    International Nuclear Information System (INIS)

    Indonesia is on the verge of energy crisis. We need at least additional 35 GW(e) new power plant in order to sustain economic growth competitively. There are many problems in realizing this demand, especially lack of infrastructure, building permits, and depletion of primary natural resources for energy etc. One of the option to look at it, is the use of nuclear power plant (NPP). However, NPP is still considered as the last option in the energy mix. Even that, the use of Uranium-based NPP such as Light Water Reactor (LWR) technology requires Uranium enrichment. Indonesia is not in the position of doing the enrichment ourselves. Therefore, option of using LWR type of reactors is not a wise one. Different approach is sought using Thorium-based NPP. Whereas thorium does not require enrichment. Thorium is also abundant in the country. This paper will discuss our approach and strategy to use thorium as an alternative in NPP. The type of reactor being considered is Thorium Molten Salt Reactor (TMSR) type of technology. It looks that thorium approach receives welcome and blessing from the Government and the people of Indonesia. The criteria being set for using thorium based NPP are: cheap, clean, safe, and reliable. Cheap means cheaper than coal. Clean means no polluted emission being produced - green nuclear, safe means no accident could occur based on regular design basis accident (DBA) and beyond of LWR type technology, reliable means high capacity factor. Based upon these criteria would make national energy policy to become sustainable

  14. Transmutation, Burn-Up and Fuel Fabrication Trade-Offs in Reduced-Moderation Water Reactor Thorium Fuel Cycles - 13502

    Energy Technology Data Exchange (ETDEWEB)

    Lindley, Benjamin A.; Parks, Geoffrey T. [University of Cambridge, Cambridge (United Kingdom); Franceschini, Fausto [Westinghouse Electric Company LLC, Cranberry Township, PA (United States)

    2013-07-01

    Multiple recycle of long-lived actinides has the potential to greatly reduce the required storage time for spent nuclear fuel or high level nuclear waste. This is generally thought to require fast reactors as most transuranic (TRU) isotopes have low fission probabilities in thermal reactors. Reduced-moderation LWRs are a potential alternative to fast reactors with reduced time to deployment as they are based on commercially mature LWR technology. Thorium (Th) fuel is neutronically advantageous for TRU multiple recycle in LWRs due to a large improvement in the void coefficient. If Th fuel is used in reduced-moderation LWRs, it appears neutronically feasible to achieve full actinide recycle while burning an external supply of TRU, with related potential improvements in waste management and fuel utilization. In this paper, the fuel cycle of TRU-bearing Th fuel is analysed for reduced-moderation PWRs and BWRs (RMPWRs and RBWRs). RMPWRs have the advantage of relatively rapid implementation and intrinsically low conversion ratios. However, it is challenging to simultaneously satisfy operational and fuel cycle constraints. An RBWR may potentially take longer to implement than an RMPWR due to more extensive changes from current BWR technology. However, the harder neutron spectrum can lead to favourable fuel cycle performance. A two-stage fuel cycle, where the first pass is Th-Pu MOX, is a technically reasonable implementation of either concept. The first stage of the fuel cycle can therefore be implemented at relatively low cost as a Pu disposal option, with a further policy option of full recycle in the medium term. (authors)

  15. Transmutation, Burn-Up and Fuel Fabrication Trade-Offs in Reduced-Moderation Water Reactor Thorium Fuel Cycles - 13502

    International Nuclear Information System (INIS)

    Multiple recycle of long-lived actinides has the potential to greatly reduce the required storage time for spent nuclear fuel or high level nuclear waste. This is generally thought to require fast reactors as most transuranic (TRU) isotopes have low fission probabilities in thermal reactors. Reduced-moderation LWRs are a potential alternative to fast reactors with reduced time to deployment as they are based on commercially mature LWR technology. Thorium (Th) fuel is neutronically advantageous for TRU multiple recycle in LWRs due to a large improvement in the void coefficient. If Th fuel is used in reduced-moderation LWRs, it appears neutronically feasible to achieve full actinide recycle while burning an external supply of TRU, with related potential improvements in waste management and fuel utilization. In this paper, the fuel cycle of TRU-bearing Th fuel is analysed for reduced-moderation PWRs and BWRs (RMPWRs and RBWRs). RMPWRs have the advantage of relatively rapid implementation and intrinsically low conversion ratios. However, it is challenging to simultaneously satisfy operational and fuel cycle constraints. An RBWR may potentially take longer to implement than an RMPWR due to more extensive changes from current BWR technology. However, the harder neutron spectrum can lead to favourable fuel cycle performance. A two-stage fuel cycle, where the first pass is Th-Pu MOX, is a technically reasonable implementation of either concept. The first stage of the fuel cycle can therefore be implemented at relatively low cost as a Pu disposal option, with a further policy option of full recycle in the medium term. (authors)

  16. Thorium fuel for light water reactors - reducing proliferation potential of nuclear power fuel cycle

    International Nuclear Information System (INIS)

    The proliferation potential of the light water reactor fuel cycle may be significantly reduced by utilization of thorium as a fertile component of the nuclear fuel. The main challenge of Th utilization is to design a core and a fuel cycle, which would be proliferation-resistant and economically feasible. This challenge is met by the Radkowsky Thorium Reactor (RTR) concept. So far the concept has been applied to a Russian design of a 1,000 MWe pressurized water reactor, known as a WWER-1000, and designated as VVERT. The following are the main results of the preliminary reference design: * The amount of Pu contained in the RTR spent fuel stockpile is reduced by 80% in comparison with a VVER of a current design. * The isotopic composition of the RTR-Pu greatly increases the probability of pre-initiation and yield degradation of a nuclear explosion. An extremely large Pu-238 content causes correspondingly large heat emission, which would complicate the design of an explosive device based on RTR-Pu. The economic incentive to reprocess and reuse the fissile component of the RTR spent fuel is decreased. The once-through cycle is economically optimal for the RTR core and cycle. To summarize all the items above: the replacement of a standard (U-based) fuel for nuclear reactors of current generation by the RTR fuel will provide an inherent barrier for nuclear weapon proliferation. This inherent barrier, in combination with existing safeguard measures and procedures is adequate to unambiguously disassociate civilian nuclear power from military nuclear power. * The RTR concept is applied to existing power plants to assure its economic feasibility. Reductions in waste disposal requirements, as well as in natural U and fabrication expenses, as compared to a standard WWER fuel, provide approximately 20% reduction in fuel cycle (authors)

  17. Automated refueling simulations of a CANDU for the exploitation of thorium fuels

    Science.gov (United States)

    Holmes, Bradford

    CANDU nuclear reactors are in a unique circumstance where they are able to utilize and exploit a number of different fuel options to provide power as a utility. Thorium, a fertile isotope found naturally, is one option that should be explored. Thorium is more abundant than uranium, which is the typical fuel in the reactor and the availability of thorium makes nuclear energy desirable to more countries. This document contains the culmination of a project that explores, tests, and analyzes the feasibility of using thorium in a CANDU reactor. The project first develops a set of twodimensional lattice and three dimensional control rod simulations using the DRAGON Version 4 nuclear physics codes. This step is repeated for many concentrations of thorium. The data generated in these steps is then used to determine a functional enrichment of thorium. This is done via a procedural elimination and optimization of certain key parameters including but not limited to average exit burnup and reactivity evolution. For the purposes of this project, an enrichment of 1 % thorium was found viable. Full core calculations were done using the DONJON 4 code. CANFUEL, a program which simulates the refueling operations of a CANDU reactor for this fuel type was developed and ran for a simulation period of one hundred days. The program and the fuel selection met all selected requirements for the entirety of the simulation period. CANFUEL requires optimization for fuel selection before it can be used extensively. The fuel selection was further scrutinized when a reactivity insertion event was simulated. The adjuster rod 11 withdrawal from the core was analyzed and compared to classical CANDU results in order to ensure no significant deviations or unwanted evolutions were encountered. For this case, the simulation results were deemed acceptable with no significant deviations from the classical CANDU case.

  18. Comparison of the radiological impacts of thorium and uranium nuclear fuel cycles

    International Nuclear Information System (INIS)

    This report compares the radiological impacts of a fuel cycle in which only uranium is recycled, as presented in the Final Generic Environmental Statement on the Use of Recycle Plutonium in Mixed Oxide Fuel in Light Water Cooled Reactors (GESMO), with those of the light-water breeder reactor (LWBR) thorium/uranium fuel cycle in the Final Environmental Statement, Light Water Breeder Reactor Program. The significant offsite radiological impacts from routine operation of the fuel cycles result from the mining and milling of thorium and uranium ores, reprocessing spent fuel, and reactor operations. The major difference between the impacts from the two fuel cycles is the larger dose commitments associated with current uranium mining and milling operations as compared to thorium mining and milling. Estimated dose commitments from the reprocessing of either fuel type are small and show only moderate variations for specific doses. No significant differences in environmental radiological impact are anticipated for reactors using either of the fuel cycles. Radiological impacts associated with routine releases from the operation of either the thorium or uranium fuel cycles can be held to acceptably low levels by existing regulations

  19. Study of thorium fuel cycles burning plutonium in the Module-HTR

    International Nuclear Information System (INIS)

    The advantages of HTR module pebble bed reactor and thorium fuel cycles are discussed in this paper. In order to reduce plutonium stockpiles, the thorium fuel cycles are used for HTR module, and plutonium is used as fissile material. The equilibrium core is calculated and analysed for the case of the different heavy metal loading and enrichment. For the case of more than 11 g heavy metal per sphere has a negative temperature coefficient, and the maximum temperature of fuel elements under regular operation and loss of coolant accident is lower than 1500 deg. C. Therefore the feasibility of above scheme is studied. (author)

  20. Alternative transportation fuels: Financing issues

    International Nuclear Information System (INIS)

    A multitude of alternative fuels could reduce air pollution and the impact of oil price shocks. Only a few of these fuels are readily available and inexpensive enough to merit serious consideration over the coming five years. In New York City, safety regulations narrow the field still further by eliminating propane. As a result, this study focuses on the three alternative fuels readily available in New York City: compressed natural gas, methanol, and electricity. Each has significant environmental benefits and each has different cost characteristics. With the Clean Air Act and the National Energy Strategy highlighting the country's need to improve urban air quality and move away from dependence on imported fuels, fleets may soon have little choice but to convert to altemative fuels. Given the potential for large infrastructure and vehicle costs, these fleets may have difficulty finding the capital to make that conversion. Ultimately, then, it will be the involvement of the private sector that will determine the success of alternative fuels. Whether it be utilities, fuel distributors or suppliers, private financing partners or others, it is critical that altemative fuels programs be structured and planned to attract their involvement. This report examines financing methods that do not involve government subsidies. It also explores financing methods that are specific to alternative fuels. Bond issues and other mechanisms that are used for conventional vehicles are not touched upon in this report. This report explores ways to spread the high cost of alternative fuels among a number of parties within the private sector. The emphasis is on structuring partnerships that suit methanol, electric, or natural gas vehicle fleets. Through these partnerships, alternative fuels may ultimately compete effectively against conventional vehicle fuels

  1. Parametric analyses of single-zone thorium-fueled molten salt reactor fuel cycle options

    International Nuclear Information System (INIS)

    Analyses of fuel cycle options based on thorium-fueled Molten Salt Reactors (MSRs) have been performed in support of fuel cycle screening and evaluation activities for the United States Department of Energy. The MSR options considered are based on thermal spectrum MSRs with 3 different separations levels: full recycling, limited recycling, and 'once-through' operation without active separations. A single-fluid, single-zone 2250 MWth (1000 MWe) MSR concept consisting of a fuel-bearing molten salt with graphite moderator and reflectors was used as the basis for this study. Radiation transport and isotopic depletion calculations were performed using SCALE 6.1 with ENDF/B-VII nuclear data. New methodology developed at Oak Ridge National Laboratory (ORNL) enables MSR analysis using SCALE, modeling material feed and removal by taking user-specified parameters and performing multiple SCALE/TRITON simulations to determine the resulting equilibrium operating conditions. Parametric analyses examined the sensitivity of the performance of a thorium MSR to variations in the separations efficiency for protactinium and fission products. Results indicate that self-sustained operation is possible with full or limited recycling but once-through operation would require an external neutron source. (authors)

  2. Alternative Fuels in Transportation

    Science.gov (United States)

    Kouroussis, Denis; Karimi, Shahram

    2006-01-01

    The realization of dwindling fossil fuel supplies and their adverse environmental impacts has accelerated research and development activities in the domain of renewable energy sources and technologies. Global energy demand is expected to rise during the next few decades, and the majority of today's energy is based on fossil fuels. Alternative…

  3. Axially heterogeneous thorium fuel designs for transuranic burning in reduced-moderation BWRs

    International Nuclear Information System (INIS)

    Reduced-moderation Boiling Water Reactors (RBWRs) can allow sustained burning of transuranics (TRU), such that full actinide recycle can be achieved. However, the void coefficient (VC) tends to become positive with reduced moderation and high TRU loading, which can severely limit the design feasibility and performance. This motivates use of thorium (Th) as an alternative feed to uranium (U), as this tends to result in a more negative VC, leading to much improved neutronic performance. While axially homogeneous fuel design is preferable for ease of fuel fabrication, it is valuable to evaluate axially heterogeneous fuel designs to see if improved neutronic performance can be realised, which could lead to a reduction in fuel reprocessing and fabrication throughput. Multi-recycled Th-TRU fuel contains Th, U, Pu and MAs, leading to a wide range of possible fuel designs. Axially heterogeneous designs are considered using 3D pincell calculations using the Monte Carlo code Serpent. Radially heterogeneous assembly designs are considered in a companion paper. Spatial separation of Th-TRU and Th-U3 into regions of the order of a few thermal neutron diffusion lengths greatly improves neutronic performance. This can be accomplished radially or axially, but radial separation results in significantly easier fuel fabrication. Axial seed-blanket heterogeneity improves neutron economy at the expense of high power peaking, such that the radially heterogeneous assembly design is preferred. Separation of Th-TRU and Th-U3 into larger regions is not effective, due to increased power density in the Th-TRU region with voiding and with burn-up, leading to a more positive VC. It is therefore concluded that there is no motivation to pursue axially heterogeneous Th-TRU RBWR burner designs. (author)

  4. Characteristics of Modular Fast Reactor SVBR-100 Using Thorium-Uranium (233) Fuel

    International Nuclear Information System (INIS)

    Natural reserves of thorium are three times as much as those of uranium. For that reason, thorium is a very promising raw material for manufacturing an artificial fissionable isotope of uranium-233 that is formed when neutrons are absorbed by thorium. Many countries are investigating characteristics of reactors using thorium-uranium (233) fuel. First, breeding ratio (BR) is of interest because only when BR = 1, the reactor can operate in a closed fuel cycle in a mode of fuel self-providing without makeup by other fissionable isotopes. The report presents the results of calculations of neutron-physical and thermal-hydraulic characteristics of SVBR-100 - lead-bismuth cooled small power modular fast reactor using thorium-uranium (233) fuel. Reactor SVBR-100 has specific properties of inherent self-protection and passive safety. The NPP modular power-units, which power equals to a value divisible by 100 MWe, can be constructed on the basis of reactor modules SVBR-100. (author)

  5. Sustainable thorium nuclear fuel cycles: A comparison of intermediate and fast neutron spectrum systems

    Energy Technology Data Exchange (ETDEWEB)

    Brown, N.R., E-mail: nbrown@bnl.gov [Brookhaven National Laboratory, Upton, NY (United States); Powers, J.J. [Oak Ridge National Laboratory, Oak Ridge, TN (United States); Feng, B.; Heidet, F.; Stauff, N.E.; Zhang, G. [Argonne National Laboratory, Argonne, IL (United States); Todosow, M. [Brookhaven National Laboratory, Upton, NY (United States); Worrall, A.; Gehin, J.C. [Oak Ridge National Laboratory, Oak Ridge, TN (United States); Kim, T.K.; Taiwo, T.A. [Argonne National Laboratory, Argonne, IL (United States)

    2015-08-15

    Highlights: • Comparison of intermediate and fast spectrum thorium-fueled reactors. • Variety of reactor technology options enables self-sustaining thorium fuel cycles. • Fuel cycle analyses indicate similar performance for fast and intermediate systems. • Reproduction factor plays a significant role in breeding and burn-up performance. - Abstract: This paper presents analyses of possible reactor representations of a nuclear fuel cycle with continuous recycling of thorium and produced uranium (mostly U-233) with thorium-only feed. The analysis was performed in the context of a U.S. Department of Energy effort to develop a compendium of informative nuclear fuel cycle performance data. The objective of this paper is to determine whether intermediate spectrum systems, having a majority of fission events occurring with incident neutron energies between 1 eV and 10{sup 5} eV, perform as well as fast spectrum systems in this fuel cycle. The intermediate spectrum options analyzed include tight lattice heavy or light water-cooled reactors, continuously refueled molten salt reactors, and a sodium-cooled reactor with hydride fuel. All options were modeled in reactor physics codes to calculate their lattice physics, spectrum characteristics, and fuel compositions over time. Based on these results, detailed metrics were calculated to compare the fuel cycle performance. These metrics include waste management and resource utilization, and are binned to accommodate uncertainties. The performance of the intermediate systems for this self-sustaining thorium fuel cycle was similar to a representative fast spectrum system. However, the number of fission neutrons emitted per neutron absorbed limits performance in intermediate spectrum systems.

  6. Sustainable thorium nuclear fuel cycles: A comparison of intermediate and fast neutron spectrum systems

    International Nuclear Information System (INIS)

    Highlights: • Comparison of intermediate and fast spectrum thorium-fueled reactors. • Variety of reactor technology options enables self-sustaining thorium fuel cycles. • Fuel cycle analyses indicate similar performance for fast and intermediate systems. • Reproduction factor plays a significant role in breeding and burn-up performance. - Abstract: This paper presents analyses of possible reactor representations of a nuclear fuel cycle with continuous recycling of thorium and produced uranium (mostly U-233) with thorium-only feed. The analysis was performed in the context of a U.S. Department of Energy effort to develop a compendium of informative nuclear fuel cycle performance data. The objective of this paper is to determine whether intermediate spectrum systems, having a majority of fission events occurring with incident neutron energies between 1 eV and 105 eV, perform as well as fast spectrum systems in this fuel cycle. The intermediate spectrum options analyzed include tight lattice heavy or light water-cooled reactors, continuously refueled molten salt reactors, and a sodium-cooled reactor with hydride fuel. All options were modeled in reactor physics codes to calculate their lattice physics, spectrum characteristics, and fuel compositions over time. Based on these results, detailed metrics were calculated to compare the fuel cycle performance. These metrics include waste management and resource utilization, and are binned to accommodate uncertainties. The performance of the intermediate systems for this self-sustaining thorium fuel cycle was similar to a representative fast spectrum system. However, the number of fission neutrons emitted per neutron absorbed limits performance in intermediate spectrum systems

  7. Comparison of radiotoxicity of uranium, plutonium, and thorium spent nuclear fuel at long-term storage

    International Nuclear Information System (INIS)

    Time dependence of radio-toxicity of actinides from spent uranium, MOX-plutonium, and thorium fuel calculated for storage during 1000 years is discussed in the paper. Calculations are based on the nuclear fuel of the VVER-1000 type reactor. Recommendations for uranium and plutonium spent fuel could be done to perform chemical separation of plutonium, americium, curium before long-term controllable storage. Americium should be separated after 50-70 years of storage for sufficient conversion of Pu-241 in Am-241. Cm-244 decays almost completely after 100 years. Extracted americium (possibly, with long-lived curium isotopes) should be directed to transmutation and plutonium should be reused. The separation of actinides is also effective to reduce decay heat power. In thorium spent fuel, the overwhelming share of radio-toxicity is determined by U-232. It is obvious that the repeated use of thorium fuel will be accompanied by accumulation of radio-toxicity. For a one-fold use of thorium fuel with deep U-233 burnup, it is necessary to perform additional deep burn-out (transmutation) of uranium fraction containing both U-233 and U-232. The further reduction of radio-toxicity by several orders can be obtained by extraction and transmutation of plutonium fraction (Pu-238). The transmutation of Th-228 - daughter nuclide of U-232 - is not necessary because Th-228 decays practically completely in 10 years together with its short-lived daughter nuclides

  8. Environmental impact of radioactive releases from recycle of thorium-based fuel using current containment technology

    International Nuclear Information System (INIS)

    The analysis of thorium mining and milling suggests that the resulting doses should be similar to those from uranium operations. An absolute comparison cannot be made at this time, however, due to differences in some assumptions utilized by the various investigators and the lack in some cases of site-specific meteorology and population data at thorium resource sites in the western United States. A distinct difference resulting from the short half-life of 220Rn (T/sub 1/2/ = 55.6 s) in the thorium decay chain compared to that for 222Rn (T/sub 1/2/ = 3.82 d) in uranium decay was noted for emissions following mill shutdown. This effect is to make potential releases following thorium mill shutdown of lesser consequence than in the uranium case. Thorium tailings activity would also decrease relatively rapidly due to the comparatively short half-life (T/sub 1/2 = 5.75 y) of 228Ra. Doses due to airborne releases from thorium-uranium carbide fuel refabrication are significantly less than that due to fuel reprocessing. Tritium is the principal contributor to reprocessing plant doses while carbon-14, 131Cs, and 232U account for most of the remaining dose. A tenfold increase in reprocessing plant CF for tritium reduces both individual and population doses by about 60%. For refabrication operations, a near linear dependence upon dose with 232U content of the fuel was calculated between concentrations of 10 ppM and 5000 ppM. Comparison of (Th, U)C and (U, Pu)C showed little difference in dose commitment, but the presence of 232U in the (Th, U) fuel causes a notable increase in the refabrication plant dose over that previously calculated for (U, Pu) type fuels

  9. Annular seed-blanket thorium fuel core concepts for heavy water moderated reactors

    International Nuclear Information System (INIS)

    New reactor concepts to implement thorium-based fuel cycles have been explored to achieve maximum resource utilization. Pressure tube heavy water reactors (PT-HWR) are highly advantageous for implementing the use of thorium-based fuels because of their high neutron economy and on-line re-fuelling capability. The use of heterogeneous seed-blanket core concepts in a PT-HWR where higher-fissile-content seed fuel bundles are physically separate from lower-fissile-content blanket bundles allows more flexibility and control in fuel management to maximize the fissile utilization and conversion of fertile fuel. The lattice concept chosen is a 35-element bundle made with a homogeneous mixture of reactor grade Pu and Th, and with a central zirconia rod to help reduce coolant void reactivity. Several annular heterogeneous seed-blanket core concepts with plutonium-thorium-based fuels in a 700-MWe-class PT-HWR were analyzed, using a once-through thorium (OTT) cycle. Different combinations of seed and blanket fuel were tested to determine the impact on core-average burnup, fissile utilization, power distributions, and other performance parameters. It was found that the various core concepts can achieve a fissile utilization that is up to 30% higher than is currently achieved in a PT-HWR using conventional natural uranium fuel bundles. Up to 67% of the Pu is consumed; up to 43% of the energy is produced from thorium, and up to 363 kg/year of U-233 is produced. Seed-blanket cores with ∼50% content of low-power blanket bundles may require power de-rating (∼58% to 65%) to avoid exceeding maximum limits for peak channel power, bundle power and linear element ratings. (authors)

  10. Checkerboard seed-blanket thorium fuel core concepts for heavy water moderated reactors

    International Nuclear Information System (INIS)

    New reactor concepts to implement thorium-based fuel cycles have been explored to achieve maximum resource utilization. Pressure tube heavy water reactors (PT-HWR) are highly advantageous for implementing the use of thorium-based fuels because of their high neutron economy and on-line re-fuelling capability. The use of heterogeneous seed-blanket core concepts in a PT-HWR where higher-fissile-content seed fuel bundles are physically separate from lower-fissile-content blanket bundles allows more flexibility and control in fuel management to maximize the fissile utilization and conversion of fertile fuel. The lattice concept chosen was a 35-element bundle made with a homogeneous mixture of reactor grade Pu (about 67 wt% fissile) and Th, and with a central zirconia rod to help reduce coolant void reactivity. Several checkerboard heterogeneous seed-blanket core concepts with plutonium-thorium-based fuels in a 700-MWe-class PT-HWR were analyzed, using a once-through thorium (OTT) cycle. Different combinations of seed and blanket fuel were tested to determine the impact on core-average burnup, fissile utilization, power distributions, and other performance parameters. It was found that various checkerboard core concepts can achieve a fissile utilization that is up to 26% higher than that achieved in a PT-HWR using more conventional natural uranium fuel bundles. Up to 60% of the Pu is consumed; up to 43% of the energy is produced from thorium, and up to 303 kg/year of Pa-233/U-233/U-235 are produced. Checkerboard cores with about 50% of low-power blanket bundles may require power de-rating (65% to 74%) to avoid exceeding maximum limits for channel and bundle powers and linear element ratings. (authors)

  11. Alternative fuels for vehicles; Alternative drivmidler

    Energy Technology Data Exchange (ETDEWEB)

    2012-02-15

    Up until 2020 and onwards the analysis indicates that especially electricity, biogas and natural gas as propellants is economically attractive compared to conventional gasoline and diesel while other fuels have the same or higher costs for petrol and diesel. Especially biogas and electricity will also offer significant reductions in CO{sub 2} emissions, but also hydrogen, methanol, DME and to a lesser extent the second generation bioethanol and most of the other alternative fuels reduce CO{sub 2} emissions. Use of the traditional food-based first generation biofuels involves, at best, only modest climate benefits if land use changes are counted, and at worst, significant negative climate effects. Natural gas as a propellant involves a moderate climate gain, but may play a role for building infrastructure and market for gaseous fuels in large fleets, thereby contributing to the phasing in of biogas for transport. The electric-based automotive fuels are the most effective due to a high efficiency of the engine and an increasing proportion of wind energy in the electricity supply. The methanol track also has a relatively high efficiency. Among the others, the track based on diesel engines (biodiesel) is more effective than the track based on gasoline/Otto engines (gas and ethanol) as a result of the diesel engine's better efficiency. For the heavy vehicles all the selected alternative fuels to varying degrees reduce emissions of CO{sub 2}, particularly DME based on wood. The only exception to this is - as for passenger cars - the propellant synthetic diesel based on coal. (LN).

  12. Conceptual design study of small long-life PWR based on thorium cycle fuel

    Science.gov (United States)

    Subkhi, M. Nurul; Su'ud, Zaki; Waris, Abdul; Permana, Sidik

    2014-09-01

    A neutronic performance of small long-life Pressurized Water Reactor (PWR) using thorium cycle based fuel has been investigated. Thorium cycle which has higer conversion ratio in thermal region compared to uranium cycle produce some significant of 233U during burn up time. The cell-burn up calculations were performed by PIJ SRAC code using nuclear data library based on JENDL 3.3, while the multi-energy-group diffusion calculations were optimized in whole core cylindrical two-dimension R-Z geometry by SRAC-CITATION. this study would be introduced thorium nitride fuel system which ZIRLO is the cladding material. The optimization of 350 MWt small long life PWR result small excess reactivity and reduced power peaking during its operation.

  13. Once-through thorium fuel cycle evaluation for TVA's Browns Ferry-3 Boiling Water Reactor

    International Nuclear Information System (INIS)

    This report documents benchmark evaluations to test thorium lattice predictive methods and neutron cross sections against available data and summarizes specific evaluations of the once-through thorium cycle when applied to the Browns Ferry-3 BWR. It was concluded that appreciable uncertainties in thorium cycle nuclear data cloud the ability to reliably predict the fuel cycle performance and that power reactor irradiations of ThO2 rods in BWRs are desirable to resolve uncertainties. Benchmark evaluations indicated that the ENDF/B-IV data used in the evaluations should cause an underprediction of U-233/ThO2 fuel reactivity, and, therefore, the results of the preliminary evaluations completed under the program should be conservative

  14. Conceptual design study of small long-life PWR based on thorium cycle fuel

    Energy Technology Data Exchange (ETDEWEB)

    Subkhi, M. Nurul [Nuclear Physics and Biophysics Research Group, Faculty of Mathematics and Natural Science, Bandung Institute of Technology (Ganesha 10 Bandung, Indonesia) and Physics Dept., Faculty of Science and Technology, State Islamic University of Sunan Gunung (Indonesia); Su' ud, Zaki; Waris, Abdul; Permana, Sidik [Nuclear Physics and Biophysics Research Group, Faculty of Mathematics and Natural Science, Bandung Institute of Technology (Ganesha 10 Bandung) (Indonesia)

    2014-09-30

    A neutronic performance of small long-life Pressurized Water Reactor (PWR) using thorium cycle based fuel has been investigated. Thorium cycle which has higher conversion ratio in thermal region compared to uranium cycle produce some significant of {sup 233}U during burn up time. The cell-burn up calculations were performed by PIJ SRAC code using nuclear data library based on JENDL 3.3, while the multi-energy-group diffusion calculations were optimized in whole core cylindrical two-dimension R-Z geometry by SRAC-CITATION. this study would be introduced thorium nitride fuel system which ZIRLO is the cladding material. The optimization of 350 MWt small long life PWR result small excess reactivity and reduced power peaking during its operation.

  15. Production of 232U from irradiation of standard and thorium-based fuels in PWR reactors

    International Nuclear Information System (INIS)

    The production of small quantities of 232U can induce radiation protection issues in the back end of the fuel cycle, particularly for thorium-based fuels. This is due to its relatively short half life (69 years) and the emission of a high energy gamma ray of 2.6 MeV at the end of its decay chain. With the depletion code MURE, we determine the different reactions pathways, and their proportions, leading to the synthesis of 232U in UO2 and (Th,Pu)O2 fuels irradiated in a PWR. Moreover, the impact, on the 232U production, of cycle times such as time separating the fabrication of the fuel and its irradiation as well as influence of the fissile content has been investigated for UO2 fuel. The impact of the thorium ore provenance and of the plutonium quality has been studied for the (Th,Pu)O2 case. (author)

  16. Alternatives for nuclear fuel disposal

    International Nuclear Information System (INIS)

    The spent fuel is one of the most important issues in the nuclear industry, currently spent fuel management is been cause of great amount of research, investments in the construction of repositories or constructing the necessary facilities to reprocess the fuel, and later to recycle the plutonium recovered in thermal reactors. What is the best solution? or, What is the best technology for a specific solution? Many countries have deferred the decision on selecting an option, while other works actively constructing repositories and others implementing the reprocessing facilities to recycle the plutonium obtained from nuclear spent fuel. In Mexico the nuclear power is limited to two reactors BWR type and medium size. So the nuclear spent fuel discharged has been accommodated at reactor's spent fuel pools. Originally these pools have enough capacity to accommodate spent fuel for the 40 years of designed plant operation. However, currently is under process an extended power up rate to 20% of their original power and also there are plans to extend operational life for 20 more years. Under these conditions there will not be enough room for spent fuel in the pools. So this work describes some different alternatives that have been studied in Mexico to define which will be the best alternative to follow. (Author)

  17. Thorium Fuel Options for Sustained Transuranic Burning in Pressurized Water Reactors - 12381

    International Nuclear Information System (INIS)

    As described in companion papers, Westinghouse is proposing the adoption of a thorium-based fuel cycle to burn the transuranics (TRU) contained in the current Used Nuclear Fuel (UNF) and transition towards a less radio-toxic high level waste. A combination of both light water reactors (LWR) and fast reactors (FR) is envisaged for the task, with the emphasis initially posed on their TRU burning capability and eventually to their self-sufficiency. Given the many technical challenges and development times related to the deployment of TRU burners fast reactors, an interim solution making best use of the current resources to initiate burning the legacy TRU inventory while developing and testing some technologies of later use is desirable. In this perspective, a portion of the LWR fleet can be used to start burning the legacy TRUs using Th-based fuels compatible with the current plants and operational features. This analysis focuses on a typical 4-loop PWR, with 17x17 fuel assembly design and TRUs (or Pu) admixed with Th (similar to U-MOX fuel, but with Th instead of U). Global calculations of the core were represented with unit assembly simulations using the Linear Reactivity Model (LRM). Several assembly configurations have been developed to offer two options that can be attractive during the TRU transmutation campaign: maximization of the TRU transmutation rate and capability for TRU multi-recycling, to extend the option of TRU recycling in LWR until the FR is available. Homogeneous as well as heterogeneous assembly configurations have been developed with various recycling schemes (Pu recycle, TRU recycle, TRU and in-bred U recycle etc.). Oxide as well as nitride fuels have been examined. This enabled an assessment of the potential for burning and multi-recycling TRU in a Th-based fuel PWR to compare against other more typical alternatives (U-MOX and variations thereof). Results will be shown indicating that Th-based PWR fuel is a promising option to multi-recycle and

  18. Production and fabrication of thorium fuels at BARC

    International Nuclear Information System (INIS)

    Thorium oxide can be consolidated by conventional powder metallurgy technique of compaction and sintering. Thorium oxide is a difficult material to sinter and even at a sintering temperature of 2000degC, the density achievable is not > 80% T.D. Hence, activated sintering with the use of additives is resorted to for achieving densities > 90% T.D. Sinterability of thoria powders obtained from different compounds such as hydroxide, hydrocarbonate, tannate, oxalate etc. has been thoroughly investigated. The effect of different additives such as CaO, CaF2, MgO, Nb2O5 on the sinterability of thoria has been extensively studied. With the addition of 0.25% Nb2O5, sintering temperature can be brought down to as low as 1150deg-1200degC. High density thoria pellets have been fabricated for use in CIRUS, DHRUVA, FBTR, PHWRs and Experimental Fission/Fusion Hybrid Systems. (author). 6 refs., 8 figs

  19. Axially homogeneous thorium fuel designs for transuranic burning in reduced-moderation BWRs

    International Nuclear Information System (INIS)

    Reduced-moderation Boiling Water Reactors (RBWRs) can allow sustained burning of transuranics (TRU), such that full actinide recycle can be achieved. However, the void coefficient (VC) tends to become positive with reduced moderation and high TRU loading, which can severely limit the design feasibility and performance. This motivates use of thorium (Th) as an alternative feed to uranium (U), as this tends to result in a more negative VC. Using coupled neutronic-thermal-hydraulic core calculations, Th-fuelled RBWRs are shown to be capable of achieving high discharge burn-ups, while incinerating an external supply of TRU. This gives them some flexibility to incinerate TRU with different isotope vectors. Spatial separation of Th-TRU and Th-U3 into regions of the order of a few thermal neutron diffusion lengths greatly improves neutronic performance. This can be accomplished radially or axially, but radial separation results in significantly easier fuel fabrication. A companion paper considers axially heterogeneous fuel designs, which are not found to deliver improved performance. A radially heterogeneous RBWR core design, can achieve 135 kg/GWthyr waste incineration rate, and at least 70–80 GWd/t discharge burn-up, depending on the TRU cooling time, and whether a single pass through a conventional PWR is used as an initial step before full recycle in an RBWR. Alternatively, a micro-heterogeneous assembly design with Th-Pu and Th-U3-MA pins can reduce fuel fabrication costs, although this limits the TRU incineration rate to ∼100 kg/GWthyr. ∼200 cm and ∼120 cm core heights are considered, with the former being generally preferred due to the possibility to match both the rating and pressure vessel size of an ABWR. (author)

  20. Thorium utilization in fast breeder reactors and in cross-progeny fuel cycles

    International Nuclear Information System (INIS)

    Thorium fuel cycles have to be closed since the benefit is obtained only when the 233U is used. India is the only country in the world, which has extensive facilities for reprocessing of irradiated Uranium and Thorium-based fuels, thermal reactors moderated by light and heavy water and 500 MWe LMFBRs. The cross-progeny fuel cycles would be a natural vision to pursue for India. This paper was written in 1982 and presented at the U.S. Japan Seminar on Thorium fuel cycle held in October 1982. The calculations performed and the results quoted in this paper are of that vintage. However, the cross section data for Th and other materials has not changed significantly since that time. The same holds for the methodologies in computer codes, diffusion theory and the other methodologies employed in this paper, versus those in computer codes currently in use. This paper is being submitted to remind the community that with the introduction of GEN IV LMFBRs, other possibilities for thorium utilization could spring forth and should be studied further and in more depth

  1. Thorium fuel cycle development activities in India (a decade of progress: 1981-1990)

    International Nuclear Information System (INIS)

    The report comprises of 72 papers on various aspects of thorium fuel cycle. These papers report the research work carried out at the Bhabha Atomic Research Centre, Bombay and other units of the Department of Atomic Energy during the decade 1981-1990. figs., tabs

  2. A preliminary assessment of thorium as a fuel for thermal reactors

    International Nuclear Information System (INIS)

    This report presents a preliminary survey of the contributing factors to total fuel cost, for a variety of potentially economic fuel cycles. U238 and Th232 are considered as fertile materials with enrichments of U235, U233 and plutonium. The total fuel cost comprises: (a) a fuel supply cost which is derived from a manufacturing cost and the fuel burnup, (b) as spent fuel credit, and (c) inventory charges. The interrelation of these three factors and their dependence on reactor flux, fuel burnup, the heat rating of the fuel and the interest rate are considered for each combination of fertile and fissile material. Results show inventory charges, spent fuel credit (hence processing costs) and fabrication costs have an important effect on the fuelling cost. In addition, using highly rated thorium-based fuels will affect reactor capital costs. Further, more detailed studies of reactor design, fuel design and fuel management schemes are now required to verify the attraction of using thorium as a reactor fuel. (author)

  3. Some peculiarities of thorium dioxide-base fuel production at NSC KIPT

    International Nuclear Information System (INIS)

    The paper describes the status of work on pyrocarbon-binder spherical fuel elements with thorium dioxide-base fuel for HTGR. Basic flow charts of manufacturing fuel microspheres, coated particles and spherical fuel elements are described. Results of investigations into the main characteristics of fuel elements and their constituents, including their operation under reactor irradiation conditions, are discussed. Some special features of the technology of pyrocarbon-bound (U,Th)O2 - base spherical FE are presented and reports the results from studies of their main characteristics. (author)

  4. Thorium utilization program quarterly progress report for the period ending February 29, 1976. [HTGR Fuel Recycle

    Energy Technology Data Exchange (ETDEWEB)

    1976-03-31

    This publication presents results of work performed under the National HTGR Fuel Recycle Program Thorium Utilization Program. The work reported includes the development of unit processes and equipment for reprocessing of HTGR fuel and the design and development of an integrated line to demonstrate the head end of HTGR reprocessing using unirradiated fuel materials. Work is also described on the development of the conceptual design of recycle facilities to identify the requirements of large-scale recycle of HTGR fuels and to incorporate the results of these studies in guidance of development activities for HTGR fuel recycle.

  5. A preliminary study of thorium and transuranic advanced fuel cycle utilization in PWR

    International Nuclear Information System (INIS)

    A typical PWR fuel element considering (TRU-Th) cycle was simulated. The study analyzed the behaviour of the thorium insertion spiked with reprocessed fuel considering different enrichments that varied from 5.5% to 7.0%. The reprocessed fuels were obtained using the ORIGEN 2.1 code from a burned PWR standard fuel (33,000 MWd/tHM burned), with 3.1% of initial enrichment, which was remained in the cooling pool for five years. The Kerf, hardening spectrum, and the fuel evolution during the burnup were evaluated. This study was performed using the SCALE 6.0. (author)

  6. A Review of Thorium Utilization as an option for Advanced Fuel Cycle-Potential Option for Brazil in the Future

    International Nuclear Information System (INIS)

    Since the beginning of Nuclear Energy Development, Thorium was considered as a potential fuel, mainly due to the potential to produce fissile uranium 233. Several Th/U fuel cycles, using thermal and fast reactors were proposed, such as the Radkwoski once through fuel cycle for PWR and VVER, the thorium fuel cycles for CANDU Reactors, the utilization in Molten Salt Reactors, the utilization of thorium in thermal (AHWR), and fast reactors (FBTR) in India, and more recently in innovative reactors, mainly Accelerator Driven System, in a double strata fuel cycle. All these concepts besides the increase in natural nuclear resources are justified by non proliferation issues (plutonium constrain) and the waste radiological toxicity reduction. The paper intended to summarize these developments, with an emphasis in the Th/U double strata fuel cycle using ADS. Brazil has one of the biggest natural reserves of thorium, estimated in 1.2 millions of tons of ThO2, as will be reviewed in this paper, and therefore RandD programs would be of strategically national interest. In fact, in the past there was some projects to utilize Thorium in Reactors, as the ''Instinto/Toruna'' Project, in cooperation with France, to utilize Thorium in Pressurized Heavy Water Reactor, in the mid of sixties to mid of seventies, and the thorium utilization in PWR, in cooperation with German, from 1979-1988. The paper will review these initiatives in Brazil, and will propose to continue in Brazil activities related with Th/U fuel cycle

  7. Safety Aspects of Thorium Fuel in Sodium-Cooled Fast Reactors

    International Nuclear Information System (INIS)

    Conclusions: ● Thorium fuel significantly reduces void positive reactivity insertion − ~2$ reduction for the ARR burner design (oxide fuel); − ~6$ reduction for the ARR breakeven design (nitride Th vs. U metal). ● ~ 1m$/K more negative Doppler for the Th breakeven design. ● Effects on transients need to be assessed (underway). ● Larger blankets, higher fuel manufacturing/reprocessing and larger reactivity swing in Th-breakeven. ● Comparable long-term capability to withstand double-fault accidents. → Thorium can be appealing for TRU burning and/or decreasing void reactivity keeping a simple design (e.g. axially homogeneous). ● Very high sources requiring remote fuel manufacturing for all cases (U and Th). ● Long term options with substantial developments/additional costs when full actinide recycle is pursued in U and for all cases in Th

  8. Preliminary fabrication studies of alternative LMFBR carbide fuels

    International Nuclear Information System (INIS)

    Preliminary fabrication studies were made of various compositions of thorium-uranium carbide and thorium-plutonium carbide fuel pellets that were prepared using the carbothermic reduction process. Temperatures of 1750 and 20000C were used during the reduction cycle. Sintering temperatures of 1800 and 20000C were used to prepare fuel pellets of low (87%) and high (> 94%) theoretical densities

  9. Fabrication of Thorium and Thorium Dioxide

    OpenAIRE

    Balakrishna Palanki

    2015-01-01

    Thorium based nuclear fuel is of immense interest to India by virtue of the abundance of Thorium and relative shortage of Uranium. Thorium metal tubes were being cold drawn using copper as cladding to prevent die seizure. After cold drawing, the copper was removed by dissolution in nitric acid. Thorium does not dissolve being passivated by nitric acid. Initially the copper cladding was carried out by inserting copper tubes inside and outside the thorium metal tube. In an innovative developmen...

  10. Study of Thorium-Plutonium Fuel for Possible Operating Cycle Extension in PWRs

    OpenAIRE

    Klara Insulander Björk; Cheuk Wah Lau; Henrik Nylén; Urban Sandberg

    2013-01-01

    Computer simulations have been carried out to investigate the possibility of extending operating cycle length in the Pressurised Water Reactor Ringhals 3 by the use of thorium-plutonium oxide fuel. The calculations have been carried out using tools and methods that are normally employed for reload design and safety evaluation in Ringhals 3. The 3-batch reload scheme and the power level have been kept unchanged, and a normal uranium oxide fuel assembly designed for a 12-month operating cycle i...

  11. A thorium-based fuel cycle for VVERs a non proliferative solution to renew nuclear power

    International Nuclear Information System (INIS)

    For several reasons such as waste disposal, expenses, proliferation and safety, global growth of the commercial nuclear power production has been effectively stagnated, since the early 1970's. A new reactor fuel cycle has been proposed which removes the concerns about proliferation and disposal of nuclear wastes that are the major obstructions in development of nuclear power production. This innovation is known as the Radkowsky Thorium Fuel(RTF)

  12. Metallography of plutonium, uranium and thorium fuels: two decades of experience in Radiometallurgy Division

    International Nuclear Information System (INIS)

    Ever since the inception of Radiometallurgy Laboratory (RML) in its early seventies optical metallography has played a key role in development and fabrication of plutonium, uranium and thorium bearing nuclear fuels. In this report, an album of photomicrographs depicts the different types of metallic, ceramic and dispersion fuels and welded section that have been evaluated in RML during the last two decades. (author). 14 refs., 1 tab

  13. Launching the Thorium fuel cycle with the molten salt fast reactor

    International Nuclear Information System (INIS)

    Starting from the Molten Salt Breeder Reactor project of Oak-Ridge, an innovative concept called Molten Salt Fast Reactor or MSFR based on a fast neutron spectrum has been proposed, resulting from extensive parametric studies in which various core arrangements, reprocessing performances and salt compositions were investigated to adapt the reactor in the framework of the deployment of a thorium based reactor fleet on a worldwide scale. In the MSFR, the liquid fuel processing is part of the reactor where a small side stream of the molten salt is processed for fission product removal and then returned to the reactor. Because of this characteristic, the MSFR can operate with widely varying fuel compositions. Thanks to this fuel composition flexibility, the MSFR concept may use as initial fissile load, 233U or uranium or also the transuranic elements currently produced by light water reactors. This paper addresses the characteristics of these different launching modes of the MSFR and the Thorium fuel cycle, in terms of safety, proliferation, breeding, and deployment capacities of these reactor configurations. To illustrate the deployment capacities of the MSFR concept, a French nuclear deployment scenario is finally presented, demonstrating that launching the Thorium fuel cycle is easily feasible while closing the current fuel cycle and optimizing the long-term waste management. (authors)

  14. Analysis of Uranium and Thorium in Radioactive Wastes from Nuclear Fuel Cycle Process

    International Nuclear Information System (INIS)

    The assessment of analysis method for uranium and thorium in radioactive wastes generated from nuclear fuel cycle process have been carried out. The uranium and thorium analysis methods in the assessment are consist of Titrimetry, UV-VIS Spectrophotometry, Fluorimetry, HPLC, Polarography, Emission Spectrograph, XRF, AAS, Alpha Spectrometry and Mass Spectrometry methods. From the assessment can be concluded that the analysis methods of uranium and thorium content in radioactive waste for low concentration level using UV-VIS Spectrometry is better than Titrimetry method. While for very low concentration level in part per billion (ppb) can be used by Neutron Activation Analysis (NAA), Alpha Spectrometry and Mass Spectrometry. Laser Fluorimetry is the best method of uranium analysis for very low concentration level. Alpha Spectrometry and ICP-MS (Inductively Coupled Plasma Mass Spectrometry) methods for isotopic analysis are favourable in the precision and accuracy aspects. Comparison of the ICP-MS and Alpha Spectrometry methods shows that the both of methods have capability to determining of uranium and thorium isotopes content in the waste samples with results comparable very well, but the time of its analysis using ICP-MS method is faster than the Alpha Spectrometry, and also the cost of analysis for ICP-MS method is cheaper. NAA method can also be used to analyze the uranium and thorium isotopes, but this method needs the reactor facility and also the time of its analysis is very long. (author)

  15. Biomedical and environmental aspects of the thorium fuel cycle: a selected, annotated bibliography

    International Nuclear Information System (INIS)

    This bibliography was compiled to assist in the evaluation of the health and environmental consequences of high specific activity thorium and related nuclides which could be released to the environment by activities related to the Thorium Fuel Cycle. The general scope covers studies regarding potential releases, environmental transport, metabolism, dosimetry, dose assessment, and overall risk assessment for radionuclides specific to the NASAP project. This publication of 740 abstracted references highlights the biological and medical aspects of thorium 228 and thorium 232 in man and animals. Similar studies on related nuclides such as radium 224, radium 226, radium 228, and thorium 230 are also emphasized. Additional categories relevant to these radionuclides are included as follows: chemical analysis; ecological aspects; energy; geological aspects; instrumentation; legal and political aspects; monitoring, measurement and analysis; physical aspects; production; radiation safety and control; and waste disposal and management. Environmental assessment and sources categories were used for entries which contain a multiple use of categories. Leading authors appear alphabetically within each category. Indexes are provided for : author(s), geographic location, keywords, title, and publication description. The bibliography contains literature dating from December 1925 to February 1978

  16. Biomedical and environmental aspects of the thorium fuel cycle: a selected, annotated bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Faust, R.A.; Fore, C.S.; Cone, M.V.; Meyer, H.R.; Till, J.E.

    1979-07-01

    This bibliography was compiled to assist in the evaluation of the health and environmental consequences of high specific activity thorium and related nuclides which could be released to the environment by activities related to the Thorium Fuel Cycle. The general scope covers studies regarding potential releases, environmental transport, metabolism, dosimetry, dose assessment, and overall risk assessment for radionuclides specific to the NASAP project. This publication of 740 abstracted references highlights the biological and medical aspects of thorium 228 and thorium 232 in man and animals. Similar studies on related nuclides such as radium 224, radium 226, radium 228, and thorium 230 are also emphasized. Additional categories relevant to these radionuclides are included as follows: chemical analysis; ecological aspects; energy; geological aspects; instrumentation; legal and political aspects; monitoring, measurement and analysis; physical aspects; production; radiation safety and control; and waste disposal and management. Environmental assessment and sources categories were used for entries which contain a multiple use of categories. Leading authors appear alphabetically within each category. Indexes are provided for : author(s), geographic location, keywords, title, and publication description. The bibliography contains literature dating from December 1925 to February 1978.

  17. The verification of Helios-1.4 for MOX, thorium and inert matrix fuels

    International Nuclear Information System (INIS)

    Helios' capability to predict the neutron behavior for plutonium-fueled and thorium-fueled cores has been verified against critical experiments and numerical benchmark problems: B and W, NEA WPPR phase 1 and 2, ESADA, TCA, PNL30-35, SAXTON, and VIP-PWR for MOX benchmarks, BNL, B and W, and IAEA thorium CRP problem for thorium benchmark, and NEA Inert Matrix Fuel (IMF) phase 1 and 2 benchmark problems for IMF. The neutron multiplication factor was adopted as a key parameter to evaluate Helios' capability, and some experiments and benchmark problem. Based on the results of Helios-1.4 verification, the conclusion so far is as followings; Helios predicts the neutron multiplication factor within the range of 1% Δk error bound and overestimates it for the core with higher moderator-to fuel ratio. Helios underestimates k at the beginning of irradiation, but predicts similar k at the end of irradiation in comparison with MCNP and the other codes. The rod power distribution calculated with Helios shows good agreement with measured one for inner region of core except the periphery near core-reflector boundary. For the depletion calculation of thorium fuel, the k calculated with Helios was rapidly decreased at the beginning of irradiation. It was concluded that Helios predicts neutron physic well for any kinds of fuel and geometry and can be used as an assembly lattice code for versatile fuel type. The extension of calculation modeling from unit lattice to 2-dimensional core, the verification of Helios-1.5, the effect of group-condensed library, and the extension of Helios verification including VIPEX experiments will be performed further. (Author). 23 refs., 88 tabs., 43 figs

  18. A study of pulse columns for thorium fuel reprocessing

    International Nuclear Information System (INIS)

    Two 5 m pulse columns with the same cartridge geometries are installed to investigate the performance. The characteristic differences of the aqueous continous and the organic continuous columns were investigated experimentally. A ternary system of 30% TBP in dodecane-acetic acid-water was adopted for the mass-transfer study. It was concluded that the overall mass-transfer coefficient was independent of whether the mass-transfer is from the dispersed to the continuous phase or from the continuous to the dispersed phase. Thorium nitrate was extracted and reextracted using both modes of operation. Both HETS and HTU were obtained. The aqueous continuous column gave much shorter HTU than the organic continuous column. In reextraction the organic continuous column gave shorter HTU. The Thorex-processes for uranium and thorium co-extraction, co-stripping, and partitioning were studied. Both acid feed solution and acid deficiend feed solution were investigated. The concentration profiles along the column height were obtained. The data were analysed with McCABE-THIELE diagrams to evaluate HETS. (orig./HP)

  19. Safety Aspects of Thorium Fuel in Sodium-Cooled Fast Reactors

    International Nuclear Information System (INIS)

    While detrimental to the breeding performance, use of thorium (Th) in Fast Reactors (FRs) has certain positive aspects: in principle, it has better thermal properties and irradiation performance than uranium (U)-based fuels, and it increases the potential burning rate of legacy transuranic waste for a burner design. The impact of thorium on the top-level operational and safety characteristics of a sodium-cooled transuranic-burner FR design is the focus of this paper. Different fuel cycle burning schemes are considered, including the development of a breakeven design to cover the long-term transition to a self-sufficient cycle. For completeness, a comparison with the counterpart U-based cores is also given. Reactivity feedback coefficients and other parameters are employed to predict the impact on the reactor passive-safety features of the various fuel cycle options. Reactivity decomposition techniques are employed to show the key contributors to the reactivity effects of the different fuels. The results show significant safety improvements fostered by implementing thorium fuel, with notable reductions in the reactivity insertion in case of core voiding, ~2$ for the burner designs and ~6$ for the breakeven design (which shows overall negative voids), while preserving a relatively simple core configuration. (author)

  20. Alternatives to traditional transportation fuels: An overview

    Energy Technology Data Exchange (ETDEWEB)

    1994-06-01

    This report presents the first compilation by the Energy Information Administration (EIA) of information on alternatives to gasoline and diesel fuel. The purpose of the report is: (1) to provide background information on alternative transportation fuels and replacement fuels compared with gasoline and diesel fuel, and (2) to furnish preliminary estimates of alternative transportation fuels and alternative fueled vehicles as required by the Energy Policy Act of 1992 (EPACT), Title V, Section 503, ``Replacement Fuel Demand Estimates and Supply Information.`` Specifically, Section 503 requires the EIA to report annually on: (1) the number and type of alternative fueled vehicles in existence the previous year and expected to be in use the following year, (2) the geographic distribution of these vehicles, (3) the amounts and types of replacement fuels consumed, and (4) the greenhouse gas emissions likely to result from replacement fuel use. Alternative fueled vehicles are defined in this report as motorized vehicles licensed for on-road use, which may consume alternative transportation fuels. (Alternative fueled vehicles may use either an alternative transportation fuel or a replacement fuel.) The intended audience for the first section of this report includes the Secretary of Energy, the Congress, Federal and State agencies, the automobile manufacturing industry, the transportation fuel manufacturing and distribution industries, and the general public. The second section is designed primarily for persons desiring a more technical explanation of and background for the issues surrounding alternative transportation fuels.

  1. HFIR spent fuel management alternatives

    International Nuclear Information System (INIS)

    The High Flux Isotope Reactor (HFIR) at Martin Marietta Energy Systems' Oak Ridge National Laboratory (ORNL) has been unable to ship its spent fuel to Savannah River Site (SRS) for reprocessing since 1985. The HFIR storage pools are expected to fill up in the February 1994 to February 1995 time frame. If a management altemative to existing HFIR pool storage is not identified and implemented before the HFIR pools are full, the HFIR will be forced to shut down. This study investigated several alternatives for managing the HFIR spent fuel, attempting to identify options that could be implemented before the HFIR pools are full. The options investigated were: installing a dedicated dry cask storage facility at ORNL, increasing HFIR pool storage capacity by clearing the HFIR pools of debris and either close-packing or stacking the spent fuel elements, storing the spent fuel at another ORNL pool, storing the spent fuel in one or more hot cells at ORNL, and shipping the spent fuel offsite for reprocessing or storage elsewhere

  2. Radiotoxicity and decay heat power of spent uranium-plutonium and thorium fuel at long-term storage

    International Nuclear Information System (INIS)

    Changes of radiotoxicity and decay heat power of actinides from spent uranium- plutonium and thorium nuclear fuel of WWER-1000 type reactors at storage during 300 years are investigated in report. (author)

  3. Alternate-fuel reactor studies

    International Nuclear Information System (INIS)

    A number of studies related to improvements and/or greater understanding of alternate-fueled reactors is presented. These studies cover the areas of non-Maxwellian distributions, materials and lifetime analysis, a 3He-breeding blanket, tritium-rich startup effects, high field magnet support, and reactor operation spanning the range from full D-T operation to operation with no tritium breeding

  4. Gas-Cooled Thorium Reactor with Fuel Block of the Unified Design

    Directory of Open Access Journals (Sweden)

    Igor Shamanin

    2015-01-01

    Full Text Available Scientific researches of new technological platform realization carried out in Russia are based on ideas of nuclear fuel breeding in closed fuel cycle and physical principles of fast neutron reactors. Innovative projects of low-power reactor systems correspond to the new technological platform. High-temperature gas-cooled thorium reactors with good transportability properties, small installation time, and operation without overloading for a long time are considered perspective. Such small modular reactor systems at good commercial, competitive level are capable of creating the basis of the regional power industry of the Russian Federation. The analysis of information about application of thorium as fuel in reactor systems and its perspective use is presented in the work. The results of the first stage of neutron-physical researches of a 3D model of the high-temperature gas-cooled thorium reactor based on the fuel block of the unified design are given. The calculation 3D model for the program code of MCU-5 series was developed. According to the comparison results of neutron-physical characteristics, several optimum reactor core compositions were chosen. The results of calculations of the reactivity margins, neutron flux distribution, and power density in the reactor core for the chosen core compositions are presented in the work.

  5. An inventory analysis of thermal-spectrum thorium-fueled molten salt reactor concepts

    International Nuclear Information System (INIS)

    Inventory analyses of thermal-spectrum, thorium-fueled molten salt reactors (MSRs) have been performed to support US Department of Energy fuel cycle screening and evaluation activities within the. A single-fluid, single-zone 2250 MWth (1000 MWe) MSR concept with a fuel-bearing molten fluoride salt moderated by graphite was used as the basis for this work. Depletion calculations were performed using SCALE 6.1.1 with ENDF/B-VII.0 nuclear data. Equilibrium conditions were evaluated for several design parameter sets using a methodology developed at Oak Ridge National Laboratory (ORNL) that enables MSR analysis by performing multiple SCALE/TRITON depletion calculations with material flow modeling calculations between time steps. Adequate modeling approximations were identified by comparing results obtained from calculations that used different modeling choices and levels of fidelity. Parametric analyses examined the performance sensitivity of a thorium MSR to different separations approaches and elemental removal efficiencies. Finally, an inventory analysis for a thorium-fueled MSR with full recycling demonstrated how these insights can be applied and showed that such a system appears feasible from a mass flow and reactivity basis. (author)

  6. Study of Thorium-Plutonium Fuel for Possible Operating Cycle Extension in PWRs

    Directory of Open Access Journals (Sweden)

    Klara Insulander Björk

    2013-01-01

    Full Text Available Computer simulations have been carried out to investigate the possibility of extending operating cycle length in the Pressurised Water Reactor Ringhals 3 by the use of thorium-plutonium oxide fuel. The calculations have been carried out using tools and methods that are normally employed for reload design and safety evaluation in Ringhals 3. The 3-batch reload scheme and the power level have been kept unchanged, and a normal uranium oxide fuel assembly designed for a 12-month operating cycle in this reactor is used as a reference. The use of plutonium as the fissile component reduces the worth of control rods and soluble boron, which makes it necessary to modify the control systems. The delayed neutron fraction is low compared with the reference, but simulations and qualitative assessments of relevant transients indicate that the reactor could still be operated safely. Differences in reactivity coefficients are mainly beneficial for the outcome of transient simulations for the thorium based fuel. A 50% extension of the current 12-month operating cycle length should be possible with thorium-plutonium mixed oxide fuel, given an upgrade of the control systems. More detailed simulations have to be carried out for some transients in order to confirm the qualitative reasoning presented.

  7. Transient and stability analysis of a BWR core with thorium-uranium fuel

    Energy Technology Data Exchange (ETDEWEB)

    Nunez-Carrera, Alejandro [Comision Nacional de Seguridad Nuclear y Salvaguardias, Dr. Barragan 779 Col. Narvarte, 03020 Mexico, DF (Mexico); Espinosa-Paredes, Gilberto [Division de Ciencias Basicas e Ingenieria, Universidad Autonoma Metropolitana, Av. San Rafael Atlixco 186, Col. Vicentina, 09340 Mexico, DF (Mexico)], E-mail: gepe@xanum.uam.mx; Francois, Juan-Luis [Departamento de Sistemas Energeticos, Facultad de Ingenieria, Universidad Nacional Autonoma de Mexico, Paseo Cuauhnahuac 8532, 62550 Jiutepec Mor. (Mexico)

    2008-08-15

    The kinetic response of a boiling water reactor (BWR) equilibrium core using thorium as a nuclear material, in an integrated blanket-seed assembly, is presented in this work. Additionally an in-house code was developed to evaluate this core under steady state and transient conditions including a stability analysis. The code has two modules: (a) the time domain module for transient analysis and (b) the frequency domain module for stability analysis. The thermal-hydraulic process is modeled by a set of five equations, considering no homogeneous flow with drift-flux approximation and non-equilibrium thermodynamic. The neutronic process is calculated with a point kinetics model. Typical BWR reactivity effects are considered: void fraction, fuel temperature, moderator temperature and control rod density. Collapsed parameters were included in the code to represent the core using an average fuel channel. For the stability analysis, in the frequency domain, the transfer function is determined by applying Laplace-transforming to the calculated pressure drop perturbations in each of the considered regions where a constant total pressure drop was considered. The transfer function was used to study the system response in the frequency domain when an inlet flow perturbation is applied. The results show that the neutronic behavior of the core with thorium uranium fuel is similar to a UO{sub 2} core, even during transient conditions. The stability and transient analysis show that the thorium-uranium fuel can be operated safely in current BWRs.

  8. Neutronic behavior of thorium fuel cycles in a very high temperature hybrid system

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Garcia, Lorena; Milian Perez, Daniel; Garcia Hernandez, Carlos; Milian Lorenzo, Daniel, E-mail: dperez@instec.cu, E-mail: cgh@instec.cu, E-mail: dmilian@instec.cu [Higher Institute of Technologies and Applied Sciences, Havana (Cuba); Velasco, Abanades, E-mail: abanades@etsii.upm.es [Department of Simulation of Thermo Energy Systems, Polytechnic University of Madrid (Spain)

    2013-07-01

    Nuclear energy needs to guarantee four important issues to be successful as a sustainable energy source: nuclear safety, economic competitiveness, proliferation resistance and a minimal production of radioactive waste. Pebble bed reactors (PBR), which are very high temperature systems together with fuel cycles based in Thorium, they could offer the opportunity to meet the sustainability demands. Thorium is a potentially valuable energy source since it is about three to four times as abundant as Uranium. It is also a widely distributed natural resource readily accessible in many countries. This paper shows the main advantages of the use of a hybrid system formed by a Pebble Bed critical nuclear reactor and two Pebble Bed Accelerator Driven Systems (ADSs) using a variety of fuel cycles with Thorium (Th+U{sup 233}, Th+Pu{sup 239} and Th+U). The parameters related to the neutronic behavior like deep burn, nuclear fuel breeding, Minor Actinide stockpile, power density profiles and other are used to compare the fuel cycles using the well-known MCNPX computational code. (author)

  9. Neutronic behavior of thorium fuel cycles in a very high temperature hybrid system

    International Nuclear Information System (INIS)

    Nuclear energy needs to guarantee four important issues to be successful as a sustainable energy source: nuclear safety, economic competitiveness, proliferation resistance and a minimal production of radioactive waste. Pebble bed reactors (PBR), which are very high temperature systems together with fuel cycles based in Thorium, they could offer the opportunity to meet the sustainability demands. Thorium is a potentially valuable energy source since it is about three to four times as abundant as Uranium. It is also a widely distributed natural resource readily accessible in many countries. This paper shows the main advantages of the use of a hybrid system formed by a Pebble Bed critical nuclear reactor and two Pebble Bed Accelerator Driven Systems (ADSs) using a variety of fuel cycles with Thorium (Th+U233, Th+Pu239 and Th+U). The parameters related to the neutronic behavior like deep burn, nuclear fuel breeding, Minor Actinide stockpile, power density profiles and other are used to compare the fuel cycles using the well-known MCNPX computational code. (author)

  10. Thorium-Based Fuels Preliminary Lattice Cell Studies for Candu Reactors

    International Nuclear Information System (INIS)

    The choice of nuclear power as a major contributor to the future global energy needs must take into account acceptable risks of nuclear weapon proliferation, in addition to economic competitiveness, acceptable safety standards, and acceptable waste disposal options. Candu reactors offer a proven technology, safe and reliable reactor technology, with an interesting evolutionary potential for proliferation resistance, their versatility for various fuel cycles creating premises for a better utilization of global fuel resources. Candu reactors impressive degree of fuel cycle flexibility is a consequence of its channel design, excellent neutron economy, on-power refueling, and simple fuel bundle. These features facilitate the introduction and exploitation of various fuel cycles in Candu reactors in an evolutionary fashion. The main reasons for our interest in Thorium-based fuel cycles have been, globally, to extend the energy obtainable from natural Uranium and, locally, to provide a greater degree of energy self-reliance. Applying the once through Thorium (OTT) cycle in existing and advanced Candu reactors might be seen as an evaluative concept for the sustainable development both from the economic and waste management points of view. Two Candu fuel bundles project will be used for the proposed analysis, namely the Candu standard fuel bundle with 37 fuel elements and the CANFLEX fuel bundle with 43 fuel elements. Using the Canadian proposed scheme - loading mixed ThO2-SEU CANFLEX bundles in Candu 6 reactors - simulated at lattice cell level led to promising conclusions on operation at higher fuel burnups, reduction of the fissile content to the end of the cycle, minor actinide content reduction in the spent fuel, reduction of the spent fuel radiotoxicity, presence of radionuclides emitting strong gamma radiation for proliferation resistance benefit. The calculations were performed using the lattice codes WIMS and Dragon (together with the corresponding nuclear data

  11. Study of CANDU thorium-based fuel cycles by deterministic and Monte Carlo methods

    International Nuclear Information System (INIS)

    In the framework of the Generation IV forum, there is a renewal of interest in self-sustainable thorium fuel cycles applied to various concepts such as Molten Salt Reactors [1, 2] or High Temperature Reactors [3, 4]. Precise evaluations of the U-233 production potential relying on existing reactors such as PWRs [5] or CANDUs [6] are hence necessary. As a consequence of its design (online refueling and D2O moderator in a thermal spectrum), the CANDU reactor has moreover an excellent neutron economy and consequently a high fissile conversion ratio [7]. For these reasons, we try here, with a shorter term view, to re-evaluate the economic competitiveness of once-through thorium-based fuel cycles in CANDU [8]. Two simulation tools are used: the deterministic Canadian cell code DRAGON [9] and MURE [10], a C++ tool for reactor evolution calculations based on the Monte Carlo code MCNP [11]. (authors)

  12. Operative experience in first campaign for reprocessing of uranium-thorium Elk-River fuel elements

    International Nuclear Information System (INIS)

    The main characteristics which differentiates the ITREC pilot plant from the other reprocessing plants are summarized. The report describes: a brief history of the Uranium-Thorium Cycle Program developed in Italy since 1960; the results obtained during the cold tests in the Remote Refabrication Cell until 1974, year in which these activities have been stopped; the operating experience in the Campaign for reprocessing of 20 Uranium-Thorium Elk-River irradiated fuel elements. In particular the results of the following operations are described: dismantling fuel elements and pool water treatment, chopping, dissolution, extraction in a Thorex acid-deficient flow-sheet. Some works of maintenance and modification during hot operations (dismantling machine, replacement of the high level waste evaporators) are also presented. The planned utilization of the ITREC plant is indicated. (author)

  13. Depletion Analysis of Modular High Temperature Gas-cooled Reactor Loaded with LEU/Thorium Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Sonat Sen; Gilles Youinou

    2013-02-01

    Thorium based fuel has been considered as an option to uranium-based fuel, based on considerations of resource utilization (Thorium is more widely available when compared to Uranium). The fertile isotope of Thorium (Th-232) can be converted to fissile isotope U-233 by neutron capture during the operation of a suitable nuclear reactor such as High Temperature Gas-cooled Reactor (HTGR). However, the fertile Thorium needs a fissile supporter to start and maintain the conversion process such as U-235 or Pu-239. This report presents the results of a study that analyzed the thorium utilization in a prismatic HTGR, namely Modular High Temperature Gas-Cooled Reactor (MHTGR) that was designed by General Atomics (GA). The collected for the modeling of this design come from Chapter 4 of MHTGR Preliminary Safety Information Document that GA sent to Department of Energy (DOE) on 1995. Both full core and unit cell models were used to perform this analysis using SCALE 6.1 and Serpent 1.1.18. Because of the long mean free paths (and migration lengths) of neutrons in HTRs, using a unit cell to represent a whole core can be non-trivial. The sizes of these cells were set to match the spectral index between unit cell and full core domains. It was found that for the purposes of this study an adjusted unit cell model is adequate. Discharge isotopics and one-group cross-sections were delivered to the transmutation analysis team. This report provides documentation for these calculations

  14. Thorium utilisation in a small long-life HTR. Part III: Composite-rod fuel blocks

    International Nuclear Information System (INIS)

    Highlights: • Composite-rod fuel blocks are proposed for a small block-type HTR. • An axial separation of fuel compacts is the most important feature. • Three patterns are presented to analyse the effects of the spatial distribution. • The spatial distribution has a large influence on the neutron spectrum. • Composite-rod fuel blocks reach a reactivity swing less than 4%. - Abstract: The U-Battery is a small long-life high temperature gas-cooled reactor (HTR) with power of 20 MWth. In order to increase its lifetime and diminish its reactivity swing, the concept of composite-rod fuel blocks with uranium and thorium was investigated. Composite-rod fuel blocks feature a specific axial separation between UO2 and ThO2 compacts in fuel rods. The design parameters, investigated by SCALE 6, include the number and spatial distribution of fuel compacts within the rods, the enrichment of uranium, the radii of fuel kernels and fuel compacts, and the packing fractions of uranium and thorium TRISO particles. The analysis shows that a lower moderation ratio and a larger inventory of heavy metals results in a lower reactivity swing. The optimal atomic carbon-to-heavy metal ratio depends on the mass fraction of U-235 and is commonly in the 160–200 range. The spatial distribution of the fuel compacts within the fuel rods has a large influence on the energy spectrum in each fuel compact and thus on the beginning-of-life reactivity and the reactivity swing. At end-of-life, the differences caused by the spatial distribution of the fuel compacts are smaller due to the fissions of U-233 in the ThO2 fuel compacts. This phenomenon enables to design fuel blocks with a very low reactivity swing, down to less than 4% in a 10-year lifetime. Among three types of thorium fuelled U-Battery blocks, the composite-rod fuel block achieves the highest end-of-life reactivity and the lowest reactivity swing

  15. Reprocessed and combined thorium fuel cycles in a PER system with a micro heterogeneous approaches

    Energy Technology Data Exchange (ETDEWEB)

    Monteiro, Fabiana B.A.; Castro, Victor F.; Faria, Rochkhudson B. de; Pereira, Claubia; Fortini, Angela, E-mail: fabianabeghini@yahoo.com.br, E-mail: victorfariacastro@gmail.com, E-mail: rochkdefaria@yahoo.com.br, E-mail: claubia@nuclear.ufmg.br, E-mail: fortini@nuclear.ufmg.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Engenharia Nuclear

    2015-07-01

    A micro heterogeneous approaches were used to study the behavior of reprocessed fuel spiked with thorium in a PWR fuel element considering (TRU-Th) cycle. The goal is to achieve a higher burnup using three different configurations to model the fuel element using SCALE 6.0. The reprocessed fuels were obtained using the ORIGEN 2.1 code from a spent PWR standard fuel (33,000 MWd/tHM burned), with 3.1% of initial enrichment. The spent fuel remained in the cooling pool for five years and then reprocessed using the UREX+ technique. Three configurations of micro heterogeneous approaches were analyzed, and the k{sub inf} and plutonium evolution during the burnup were evaluated. The preliminary results show that the behavior of advanced fuel based on transuranic elements spiked with thorium, and micro heterogeneous approach are satisfactory in PWRs, and the configuration that use a combination of Th and TRU (configuration 1) seems to be the most promising once has higher values for k{sub inf} during the burnup, compared with other configurations. (author)

  16. Transuranic Waste Burning Potential of Thorium Fuel in a Fast Reactor - 12423

    International Nuclear Information System (INIS)

    Westinghouse Electric Company (referred to as 'Westinghouse' in the rest of this paper) is proposing a 'back-to-front' approach to overcome the stalemate on nuclear waste management in the US. In this approach, requirements to further the societal acceptance of nuclear waste are such that the ultimate health hazard resulting from the waste package is 'as low as reasonably achievable'. Societal acceptability of nuclear waste can be enhanced by reducing the long-term radiotoxicity of the waste, which is currently driven primarily by the protracted radiotoxicity of the transuranic (TRU) isotopes. Therefore, a transition to a more benign radioactive waste can be accomplished by a fuel cycle capable of consuming the stockpile of TRU 'legacy' waste contained in the LWR Used Nuclear Fuel (UNF) while generating waste which is significantly less radio-toxic than that produced by the current open U-based fuel cycle (once through and variations thereof). Investigation of a fast reactor (FR) operating on a thorium-based fuel cycle, as opposed to the traditional uranium-based is performed. Due to a combination between its neutronic properties and its low position in the actinide chain, thorium not only burns the legacy TRU waste, but it does so with a minimal production of 'new' TRUs. The effectiveness of a thorium-based fast reactor to burn legacy TRU and its flexibility to incorporate various fuels and recycle schemes according to the evolving needs of the transmutation scenario have been investigated. Specifically, the potential for a high TRU burning rate, high U-233 generation rate if so desired and low concurrent production of TRU have been used as metrics for the examined cycles. Core physics simulations of a fast reactor core running on thorium-based fuels and burning an external TRU feed supply have been carried out over multiple cycles of irradiation, separation and reprocessing. The TRU burning capability as well as the core isotopic content have been characterized

  17. Performance of the fissionTPC and the Potential to Advance the Thorium Fuel Cycle

    Science.gov (United States)

    Towell, Rusty; Niffte Collaboration

    2014-09-01

    The NIFFTE fission Time Projection Chamber (fissionTPC) is a powerful tool that is being developed to take precision measurements of neutron-induced fission cross sections of transuranic elements. During the last run at the Los Alamos Neutron Science Center (LANSCE) the fully instrumented TPC took data for the first time. The exquisite tracking capabilities of this device allow the full reconstruction of charged particles produced by neutron beam induced fissions from a thin central target. The wealth of information gained from this approach will allow cross section systematics to be controlled at the level of 1%. The fissionTPC performance from this run will be shared. These results are critical to the development of advanced uranium-fueled reactors. However, there are clear advantages to developing thorium-fueled reactors including the abundance of thorium verses uranium, minimizing radioactive waste, improved reactor safety, and enhanced proliferation resistance. The potential for using the fissionTPC to measure needed cross sections important to the development of thorium fueled nuclear reactors will also be discussed.

  18. Comparative analysis of thorium and uranium fuel for transuranic recycle in a sodium cooled Fast Reactor

    International Nuclear Information System (INIS)

    Highlights: • Thorium as support fertile material for TRU transmutation in Fast Reactors. • Comparative analysis of Th and U based breakeven and burner Fast Reactors. • Thorium fosters significant advantages in terms of safety parameters. • Inherent safety is investigated through quasi-static reactivity and energy balances. • Th use in low-CR Fast Reactors does not reduce fuel decay heat and neutron sources. - Abstract: The present paper compares the reactor physics and transmutation performance of sodium-cooled Fast Reactors (FRs) for TRansUranic (TRU) burning with thorium (Th) or uranium (U) as fertile materials. The 1000 MWt Toshiba-Westinghouse Advanced Recycling Reactor (ARR) conceptual core has been used as benchmark for the comparison. Both burner and breakeven configurations sustained or started with a TRU supply, and assuming full actinide homogeneous recycle strategy, have been developed. State-of-the-art core physics tools have been employed to establish fuel inventory and reactor physics performances for equilibrium and transition cycles. Results show that Th fosters large improvements in the reactivity coefficients associated with coolant expansion and voiding, which enhances safety margins and, for a burner design, can be traded for maximizing the TRU burning rate. A trade-off of Th compared to U is the significantly larger fuel inventory required to achieve a breakeven design, which entails additional blankets at the detriment of core compactness as well as fuel manufacturing and separation requirements. The gamma field generated by the progeny of U-232 in the U bred from Th challenges fuel handling and manufacturing, but in case of full recycle, the high contents of Am and Cm in the transmutation fuel impose remote fuel operations regardless of the presence of U-232

  19. Loss of Power to Recirculation Pumps in the VVER-1000 Reactor with Thorium Power, Ltd. Thorium Seed and Blanket Fuel Assemblies

    International Nuclear Information System (INIS)

    The Thorium Power, Ltd. seed and blanket fuel assembly design for VVER-1000 reactors was analyzed against three accident conditions. The three scenarios considered were loss of power to all four main circulating coolants pumps; loss of power to one main coolant pump and loss of power to a coolant pump with a seized rotor. The analysis was performed using the TIGR-1 point kinetics code developed by OKBM, the Russian experimental mechanical engineering design bureau that develops certified fuel assembly designs for the VVER-1000 reactor, in collaboration with the Russian Research Centre 'Kurchatov Institute'. In all cases, the Thorium Power seed and blanket fuel assembly met or exceeded all requisite VVER-1000 regulatory safety limits. (authors)

  20. Loss of Power to Recirculation Pumps in the VVER-1000 Reactor with Thorium Power, Ltd. Thorium Seed and Blanket Fuel Assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Morozov, Alexei; Montgomery, Michael; Mushakov, Andrey [Thorium Power, Ltd, 1600 Tysons Blvd Suite 550, McLean, Va 22102 (United States)

    2009-06-15

    The Thorium Power, Ltd. seed and blanket fuel assembly design for VVER-1000 reactors was analyzed against three accident conditions. The three scenarios considered were loss of power to all four main circulating coolants pumps; loss of power to one main coolant pump and loss of power to a coolant pump with a seized rotor. The analysis was performed using the TIGR-1 point kinetics code developed by OKBM, the Russian experimental mechanical engineering design bureau that develops certified fuel assembly designs for the VVER-1000 reactor, in collaboration with the Russian Research Centre 'Kurchatov Institute'. In all cases, the Thorium Power seed and blanket fuel assembly met or exceeded all requisite VVER-1000 regulatory safety limits. (authors)

  1. Philosophy of future ready thorium reactor designs

    International Nuclear Information System (INIS)

    Due to modest uranium reserves and abundant thorium resources, thorium fuel cycle and thorium based reactors are very important to India. Over a period of time India has developed expertise in all aspects of thorium utilisation starting from mining, metal extraction, fuel fabrication, irradiation in reactors, reprocessing, and recycling the recovered 233U. In-line with the maturing of these technologies, development of innovative and advanced reactors is being pursued. India is developing technologies for thorium based reactors in many configurations, from light water cooled designs to high temperature liquid metal and molten salt cooled options. A research reactor, KAMINI, based on 233U was commissioned at Indira Gandhi Centre for Atomic Research (IGCAR) in Kalpakkam in 1996. This is the only reactor in the world currently operating with 233U based fuel. Advanced Heavy Water Reactor (AHWR) aims at technology development for industrial scale thorium utilisation. Thorium is also planned to be used in the High Temperature Reactors, which hold promise of producing hydrogen as an alternate energy carrier for transport applications, thus ensuring long term energy security. For long-term sustainability, it is envisaged to take full advantage of the unique characteristics of 233U - thorium fuel cycle, through development and deployment of advanced nuclear energy systems, such as molten salt breeder reactors and accelerator-driven sub-critical systems

  2. Feasibility of Thorium Fuel Cycles in a Very High Temperature Pebble-Bed Hybrid System

    Directory of Open Access Journals (Sweden)

    L.P. Rodriguez

    2015-08-01

    Full Text Available Nuclear energy presents key challenges to be successful as a sustainable energy source. Currently, the viability of the use thorium-based fuel cycles in an innovative nuclear energy generation system is being investigated in order to solve these key challenges. In this work, the feasibility of three thorium-based fuel cycles (232Th-233U, 232Th-239Pu, and 232Th-U in a hybrid system formed by a Very High Temperature Pebble-Bed Reactor (VHTR and two Pebble-Bed Accelerator Driven Systems (ADSs was evaluated using parameters related to the neutronic behavior such as nuclear fuel breeding, minor actinide stockpile, the energetic contribution of each fissile isotope, and the radiotoxicity of the long lived wastes. These parameters were used to compare the fuel cycles using the well-known MCNPX ver. 2.6e computational code. The results obtained confirm that the 232Th-233U fuel cycle is the best cycle for minimizing the production of plutonium isotopes and minor actinides. Moreover, the inclusion of the second stage in the ADSs demonstrated the possibility of extending the burnup cycle duration and reducing the radiotoxicity of the discharged fuel from the VHTR.

  3. Introduction of thorium-based fuels in high conversion pressurized water reactors

    International Nuclear Information System (INIS)

    Pressurized water reactors (PWRs) are likely to produce the major portion of nuclear electricity during the 21. century. Nevertheless, even with the recycling of plutonium within MOX fuel, the utilization rate of uranium is very low and can be improved. Indeed, it grows significantly with the conversion ratio (CR) above the value of 0.8. The CR measures the competition between the production and the consumption rate of fissile isotopes as a function of the burnup. Thus, a CR higher than unity corresponds to a breeder reactor. The CR is the key factor that must be improved to allow a better use of natural uranium resources. A way to improve the CR would be to use thorium instead of uranium as a fertile material through the excellent qualities of its daughter, 233U. Consequently, the aim of this paper is to investigate the use of thorium in high conversion pressurized water reactors (HCPWR) with a reduced moderator-to-fuel volume ratio using a high plutonium content in a hexagonal lattice. This study focuses on two heterogeneous concepts that fulfill the following criteria: a large production of 233U, the respect of safety aspects, and a cycle length higher or equal to 300 equivalent full-power days. The first core, named M-ThPu, has 21% of fertile fuel assemblies composed of depleted uranium and 79% of MOX fuel assemblies containing ThPuO2 fuel, whereas the second core, named FA-Th, has ThO2 fertile assemblies and U-depleted-PuO2 fuel assemblies, including axial layers of depleted uranium only. For each concept, the recycling of 233U with thorium in order to decrease the plutonium content in core has also been discussed. The conclusion for both concepts is that ∼25% of the PWR (with UOX fuel) could be replaced by HCPWR if 233U is reintroduced directly in each core concept. Therefore, this transition study shows no penalty in terms of natural uranium economy in moving toward a thorium fuel cycle in combination with the existing uranium cycle. (authors)

  4. Thorium: Issues and prospects in Malaysia

    Energy Technology Data Exchange (ETDEWEB)

    AL-Areqi, Wadeeah M.; Majid, Amran Ab.; Sarmani, Sukiman; Bahri, Che Nor Aniza Che Zainul [Nuclear Science Programme, School of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Malaysia. walareqi@yahoo.com (Malaysia)

    2015-04-29

    In Malaysia, thorium exists in minerals and rare earth elements production residue. The average range of thorium content in Malaysian monazite and xenotime minerals was found about 70,000 and 15,000 ppm respectively. About 2,636 tonnes of Malaysian monazite was produced for a period of 5 years (2006-2010) and based on the above data, it can be estimated that Malaysian monazite contains about 184.5 tonnes of thorium. Although thorium can become a major radiological problem to our environment, but with the significant deposit of thorium in Malaysian monazite, it has a prospect as a future alternative fuel in nuclear technology. This paper will discuss the thorium issues in Malaysia especially its long term radiological risks to public health and environment at storage and disposal stages, the prospect of exploring and producing high purity thorium from our rare earth elements minerals for future thorium based reactor. This paper also highlights the holistic approach in thorium recovery from Malaysian rare earth element production residue to reduce its radioactivity and extraction of thorium and rare earth elements from the minerals with minimum radiological impact to health and environment.

  5. Thorium: Issues and prospects in Malaysia

    Science.gov (United States)

    AL-Areqi, Wadeeah M.; Majid, Amran Ab.; Sarmani, Sukiman; Bahri, Che Nor Aniza Che Zainul

    2015-04-01

    In Malaysia, thorium exists in minerals and rare earth elements production residue. The average range of thorium content in Malaysian monazite and xenotime minerals was found about 70,000 and 15,000 ppm respectively. About 2,636 tonnes of Malaysian monazite was produced for a period of 5 years (2006-2010) and based on the above data, it can be estimated that Malaysian monazite contains about 184.5 tonnes of thorium. Although thorium can become a major radiological problem to our environment, but with the significant deposit of thorium in Malaysian monazite, it has a prospect as a future alternative fuel in nuclear technology. This paper will discuss the thorium issues in Malaysia especially its long term radiological risks to public health and environment at storage and disposal stages, the prospect of exploring and producing high purity thorium from our rare earth elements minerals for future thorium based reactor. This paper also highlights the holistic approach in thorium recovery from Malaysian rare earth element production residue to reduce its radioactivity and extraction of thorium and rare earth elements from the minerals with minimum radiological impact to health and environment.

  6. Thorium utilization program. Quarterly progress report for the period ending November 30, 1976. [HTGR fuel recycle

    Energy Technology Data Exchange (ETDEWEB)

    1976-12-01

    This publication continues the quarterly series presenting results of work performed under the National HTGR Fuel Recycle Program (also known as the Thorium Utilization Program). Results of work on this program prior to June 1974 were included in a quarterly series on the HTGR Base Program. The work reported includes the development of unit processes and equipment for reprocessing of HTGR fuel, the design and development of an integrated pilot line to demonstrate the head end of HTGR reprocessing using unirradiated fuel materials, and design work in support of Hot Engineering Tests (HET). Work is also described on trade-off studies concerning the required design of facilities and equipment for the large-scale recycle of HTGR fuels in order to guide the development activities for HTGR fuel recycle.

  7. Measurements of Fission Cross Sections for the Isotopes relevant to the Thorium Fuel Cycle

    CERN Multimedia

    2002-01-01

    The present concern about a sustainable energy supply is characterised by a considerable uncertainty: the green house effect and foreseeable limits in fossil fuel resources on the one hand, the concern about the environmental impact of nuclear fission energy and the long term fusion research on the other hand, have led to the consideration of a variety of advanced strategies for the nuclear fuel cycle and related nuclear energy systems. The present research directories concern such strategies as the extension of the life span of presently operating reactors, the increase of the fuel burn-up, the plutonium recycling, and in particular the incineration of actinides and long-Lived fission products, the accelerator driven systems (ADS), like the "Energy Amplifier" (EA) concept of C. Rubbia, and the possible use of the Thorium fuel cycle. The detailed feasibility study and safety assessment of these strategies requires the accurate knowledge of neutron nuclear reaction data. Both, higher fuel burn-up and especiall...

  8. Optimization of thorium-uranium content in a 54-element fuel bundle for use in a CANDU-SCWR

    International Nuclear Information System (INIS)

    A new 54-element fuel bundle design has been proposed for use in a pressure-tube supercritical water-cooled reactor, a pre-conceptual evolution of existing CANDU reactors. Pursuant to the goals of the Generation IV International Forum regarding advancement in nuclear fuel cycles, optimization of the thorium and uranium content in each ring of fuel elements has been studied with the objectives of maximizing the achievable fuel utilization (burnup) and total thorium content within the bundle, while simultaneously minimizing the linear element ratings and coolant void reactivity. The bundle was modeled within a reactor lattice cell using WIMS-AECL, and the uranium and thorium content in each ring of fuel elements was optimized using a weighted merit function of the aforementioned criteria and a metaheuristic search algorithm. (author)

  9. Comprehensive study of lattice cell calculations for thorium based fuel cycle in light water reactors using SRAC code

    International Nuclear Information System (INIS)

    The designers of the innovative reactors have proposed a number of approaches to increasing resource efficiency. Adding thorium, a fertile material, to the fuel is considered in this report. Under this approach, a large portion of the reactor output is produced by fissioning of the 233U resulting from neutron capture by thorium, which results in reduced requirements for naturally-occurring fissile uranium (235U). The proliferation potential of the light water reactor fuel cycle may be significantly reduced by utilization of thorium as a fertile component of the nuclear fuel. The concept of using Th-233U as fuel has been applied to an existing LWR design as compare with another fuel cycles (UO2 and MOX). SRAC code is extensive used to investigate the lattice cell problem. (author)

  10. Alternate-Fueled Flight: Halophytes, Algae, Bio-, and Synthetic Fuels

    Science.gov (United States)

    Hendricks, R. C.

    2012-01-01

    Synthetic and biomass fueling are now considered to be near-term aviation alternate fueling. The major impediment is a secure sustainable supply of these fuels at reasonable cost. However, biomass fueling raises major concerns related to uses of common food crops and grasses (some also called "weeds") for processing into aviation fuels. These issues are addressed, and then halophytes and algae are shown to be better suited as sources of aerospace fuels and transportation fueling in general. Some of the history related to alternate fuels use is provided as a guideline for current and planned alternate fuels testing (ground and flight) with emphasis on biofuel blends. It is also noted that lessons learned from terrestrial fueling are applicable to space missions. These materials represent an update (to 2009) and additions to the Workshop on Alternate Fueling Sustainable Supply and Halophyte Summit at Twinsburg, Ohio, October 17 to 18, 2007.

  11. Alternative fuels: a Brazilian outlook

    International Nuclear Information System (INIS)

    This paper focuses on studies and information related to the use of alternative fuels in Brazil. The first part of this paper deals with the economics of different biomass technologies. The analysis consists of a careful costing of all operations involved. The study deals with wood, sugar cane and cassava, since these crops are exploited for commercial purposes in Brazil. Corn, although a useful raw material for producing ethanol in the United States, is not used for this purpose in Brazil. The second part deals with the industrial technologies used to convert biomass into energy. We consider several forms of energy derived from biomass and evaluate the economics of the processes. When opportune, we compare costs with those of the North American market. Market analysis and displacement of conventional energy are the subject of the third part of the paper. While the cost of each product is evaluated in most cases; in others the current market price is used. Finally, we raise the issues of institutional problems and planning and offer some conclusions on the future of biomass as an alternative energy source. The technological discussion in this paper is based on the Brazilian experience in producing ethanol and other fuels from biomass. It is possible to extrapolate the Brazilian experience to other developing countries. The observations made in this chapter are based on the conditions prevalent in the Brazilian south-central agricultural region, specifically the state of Sao Paulo. (author). 91 refs., 16 figs., 11 tabs

  12. Alternative fuel cycle options: performance characteristics and impact on nuclear power growth potential

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Y. I.; Till, C. E.; Rudolph, R. R.; Deen, J. R.; King, M. J.

    1977-09-01

    The fuel utilization characteristics for LWR, SSCR, CANDU and LMFBR reactor concepts are quantified for various fuel cycle options, including once-through cycles, thorium cycles, and denatured cycles. The implications of various alternative reactor deployment strategies on the long-term nuclear power growth potential are then quantified in terms of the maximum nuclear capacity that can be achieved and the growth pattern over time, subject to the constraint of a fixed uranium-resource base. The overall objective of this study is to shed light on any large differences in the long-term potential that exist between various alternative reactor/fuel cycle deployment strategies.

  13. Neutronic analysis of the PBMR-400 full core using thorium fuel mixed with plutonium or minor actinides

    International Nuclear Information System (INIS)

    Highlights: ► Neutronic calculations for PBMR 400 were conducted with the computer codes MCNP and MONTEBURNS 2.0. ► The criticality and burnup were investigated for reactor grade plutonium and minor actinides. ► We found that the use of these new fuels in PBMRs would reduce the nuclear waste repository significantly. -- Abstract: Time evolution of criticality and burnup grades of the PBMR were investigated for reactor grade plutonium and minor actinides in the spent fuel of light water reactors (LWRs) mixed with thoria. The calculations were performed by employing the computer codes MCNP and MONTEBURNS 2.0 and using the ENDF/B-V nuclear data library. Firstly, the plutonium–thorium and minor actinides–thorium ratio was determined by using the initial keff value of the original uranium fuel design. After the selection of the plutonium/minor actinides–thorium mixture ratio, the time-dependent neutronic behavior of the reactor grade plutonium and minor actinides and original fuels in a PBMR-400 reactor was calculated by using the MCNP code. Finally, keff, burnup and operation time values of the fuels were compared. The core effective multiplication factor (keff) for the original fuel which has 9.6 wt.% enriched uranium was computed as 1.2395. Corresponding to this keff value the reactor grade plutonium/thorium and minor actinide/thorium oxide mixtures were found to be 30%/70% and 50%/50%, respectively. The core lives for the original, the reactor grade plutonium/thorium and the minor actinide/thorium fuels were calculated as ∼3.2, ∼6.5 and ∼5.5 years, whereas, the corresponding burnups came out to be 99,000, ∼190,000 and ∼166,000 MWD/T, respectively, for an end of life keff set equal to 1.02.

  14. Model for the behaviour of thorium and uranium fuels at pelletization

    International Nuclear Information System (INIS)

    In this work, a model for the behaviour of thorium-uranium-mixed oxide microspheres in the pelletizing process is presented. This model was developed in a program whose objective was to demonstrate the viability of producing fissile material through the utilization of thorium in pressurized water reactors. This is important because it allows the saving of the strategic uranium reserves, and makes it possible the nuclear utilization of the large brazilian thorium reserves. The objective was to develop a model for optimizing physical properties of the microspheres, such as density, fracture strength and specific surface, so as to produce fuel pellets with microstructure, density, open porosity and impurity content, in accordance with the fuel specification. And, therefore, to adjust the sol-gel processing parameters in order to obtain these properties, and produce pellets with an optimized microstructure, adequate to a stable behaviour under irradiation. The model made it clear that to achieve this objective, it is necessary to produce microspheres with density and specific surface as small as possible. By changing the sol-gel processing parameters, microspheres with the desired properties were produced, and the model was experimentally verified by manufacturing fuel pellets with optimized microstructures, density, open porosity and impurity content, meeting the specifications for this new nuclear fuel for pressurized water reactors. Furthermore it was possible to obtain mathematical expressions that enables to calculate from the microspheres properties and the utilized compaction pressure, the sinter density that will be obtained in the sintered pellet and the necessary compaction pressure to reach the sintered density specified for the fuel. (author)

  15. Operation of CANDU power reactor in thorium self-sufficient fuel cycle

    Indian Academy of Sciences (India)

    B R Bergelson; A S Gerasimov; G V Tikhomirov

    2007-02-01

    This paper presents the results of calculations for CANDU reactor operation in thorium fuel cycle. Calculations are performed to estimate the feasibility of operation of heavy-water thermal neutron power reactor in self-sufficient thorium cycle. Parameters of active core and scheme of fuel reloading were considered to be the same as for standard operation in uranium cycle. Two modes of operations are discussed in the paper: mode of preliminary accumulation of 233U and mode of operation in self-sufficient cycle. For the mode of accumulation of 233U it was assumed for calculations that plutonium can be used as additional fissile material to provide neutrons for 233U production. Plutonium was placed in fuel channels, while 232Th was located in target channels. Maximum content of 233U in target channels was estimated to be ∼ 13 kg/t of ThO2. This was achieved by irradiation for six years. The start of the reactor operation in the self-sufficient mode requires 233U content to be not less than 12 kg/t. For the mode of operation in self-sufficient cycle, it was assumed that all channels were loaded with identical fuel assemblies containing ThO2 and certain amount of 233U. It is shown that nonuniform distribution of 233U in fuel assembly is preferable.

  16. Transmutation Strategy Using Thorium-Reprocessed Fuel ADS for Future Reactors in Vietnam

    Directory of Open Access Journals (Sweden)

    Thanh Mai Vu

    2013-01-01

    Full Text Available Nuclear power is believed to be a key to the energy security for a developing country like Vietnam where the power demanding increases rapidly every year. Nevertheless, spent nuclear fuel from nuclear power plants is the source of radiotoxic and proliferation risk. A conceptual design of ADS utilizing thorium fuel as a based fuel and reprocessed fuel as a seed for nuclear waste transmutation and energy production is proposed as one of the clean, safe, and economical solutions for the problem. In the design, 96 seed assemblies and 84 blanket assemblies were inserted into the core to make a heterogeneous subcritical core configuration. Introducing thorium fuel into the core offers an effective way to transmute plutonium and minor actinide (MA and gain energy from this process. Transmutation rate as a function of burnup is estimated using MCNPX 2.7.0 code. Results show that by using the seed-blanket designed ADS, at 40 GWd/t burnup, 192 kg of plutonium and 156 kg of MA can be eliminated. Equivalently, 1  ADS can be able to transmute the transuranic (TRU waste from 2  LWRs. 14 units of ADS would be required to eliminate TRUs from the future reactors to be constructed in Vietnam.

  17. The mode of operation of CANDU power reactor in thorium self-sufficient fuel cycle

    Directory of Open Access Journals (Sweden)

    Bergelson Boris R.

    2008-01-01

    Full Text Available This paper presents the results of calculations for CANDU reactor operation in the thorium fuel cycle. The calculations were performed to estimate feasibility of operation of a heavy-water thermal neutron power reactor in the self-sufficient thorium cycle. The parameters of the active core and the scheme of fuel reloading were considered to be the same as for the standard operation in the uranium cycle. Two modes of operation are discussed in the paper: the mode of preliminary accumulation of 233U and the mode of operation in the self-sufficient cycle. For calculations for the mode of accumulation of 233U, it was assumed that plutonium was used as the additional fissile material to provide neutrons for 233U production. Plutonium was placed in fuel channels, while 232Th was located in target channels. The maximum content of 233U in the target channels was about 13 kg/t of ThO2. This was achieved by six year irradiation. The start of reactor operation in the self-sufficient mode requires content of 233U not less than 12 kg/t. For the mode of operation in the self-sufficient cycle, it was assumed that all the channels were loaded with the identical fuel assemblies containing ThO2 and a certain amount of 233U. It was shown that the non-uniform distribution of 233U in a fuel assembly is preferable.

  18. Chemical analysis used in nuclear fuels reprocessing of uranium and thorium

    International Nuclear Information System (INIS)

    An overall review of the analytical chemistry in nuclear fuel reprocessing is done. In Purex and Thorex process flowsheets, the analyses required to the control of the process, balance and accountability of fissile and fertile materials, and final product specification are pointed out. Some analytical methods applied to the determination of uranium, plutonium, thorium, nitric acid, tributylphosphate and fission products are described. Specific features of the analytical laboratories are presented. The radioactivity level of the samples requires facilities as shielded cells and glove boxes, and handling by remote control. Finally it is reported an application of one analytical method to evaluate thorium content in organic and aqueous solutions, in cold tests of Thorex process. These tests were performed at CDTN/NUCLEBRAS. (author)

  19. Optimization of small long-life PWR based on thorium fuel

    Science.gov (United States)

    Subkhi, Moh Nurul; Suud, Zaki; Waris, Abdul; Permana, Sidik

    2015-09-01

    A conceptual design of small long-life Pressurized Water Reactor (PWR) using thorium fuel has been investigated in neutronic aspect. The cell-burn up calculations were performed by PIJ SRAC code using nuclear data library based on JENDL 3.2, while the multi-energy-group diffusion calculations were optimized in three-dimension X-Y-Z geometry of core by COREBN. The excess reactivity of thorium nitride with ZIRLO cladding is considered during 5 years of burnup without refueling. Optimization of 350 MWe long life PWR based on 5% 233U & 2.8% 231Pa, 6% 233U & 2.8% 231Pa and 7% 233U & 6% 231Pa give low excess reactivity.

  20. Thorium base fuels reprocessing at the L.P.R. (Radiochemical Processes Laboratory) experimental plant

    International Nuclear Information System (INIS)

    The availability of the LPR (Radiochemical Processes Laboratory) plant offers the possibility to demonstrate and create the necessary technological basis for thorium fuels reprocessing. To this purpose, the solvents extraction technique is used, employing TBP (at 30%) as solvent. The process is named THOREX, a one-cycle acid, which permits an adequate separation of Th232 and U233 components and fission products. For thorium oxide elements dissolution, the 'chopp-leach' process (installed at LPR) is used, employing a NO3 H 13N, 0.05M FH and 0.1M Al (NO3)3, as solvent. To adapt the pilot plant to the flow-sheet requirements proposed, minor modifications must be carried out in the interconnection of the existing decanting mixers. The input of the plant has been calculated by Origin Code modified for irradiations in reactors of the HWR type. (Author)

  1. Optimization of small long-life PWR based on thorium fuel

    Energy Technology Data Exchange (ETDEWEB)

    Subkhi, Moh Nurul, E-mail: nsubkhi@students.itb.ac.id [Nuclear Physics and Biophysics Research Group, Faculty of Mathematics and Natural Science, Bandung Institute of Technology. Jalan Ganesha 10, Bandung (Indonesia); Physics Dept., Faculty of Science and Technology, State Islamic University of Sunan Gunung Djati Bandung Jalan A.H Nasution 105 Bandung (Indonesia); Suud, Zaki, E-mail: szaki@fi.itb.ac.id; Waris, Abdul; Permana, Sidik [Nuclear Physics and Biophysics Research Group, Faculty of Mathematics and Natural Science, Bandung Institute of Technology. Jalan Ganesha 10, Bandung (Indonesia)

    2015-09-30

    A conceptual design of small long-life Pressurized Water Reactor (PWR) using thorium fuel has been investigated in neutronic aspect. The cell-burn up calculations were performed by PIJ SRAC code using nuclear data library based on JENDL 3.2, while the multi-energy-group diffusion calculations were optimized in three-dimension X-Y-Z geometry of core by COREBN. The excess reactivity of thorium nitride with ZIRLO cladding is considered during 5 years of burnup without refueling. Optimization of 350 MWe long life PWR based on 5% {sup 233}U & 2.8% {sup 231}Pa, 6% {sup 233}U & 2.8% {sup 231}Pa and 7% {sup 233}U & 6% {sup 231}Pa give low excess reactivity.

  2. Optimization of small long-life PWR based on thorium fuel

    International Nuclear Information System (INIS)

    A conceptual design of small long-life Pressurized Water Reactor (PWR) using thorium fuel has been investigated in neutronic aspect. The cell-burn up calculations were performed by PIJ SRAC code using nuclear data library based on JENDL 3.2, while the multi-energy-group diffusion calculations were optimized in three-dimension X-Y-Z geometry of core by COREBN. The excess reactivity of thorium nitride with ZIRLO cladding is considered during 5 years of burnup without refueling. Optimization of 350 MWe long life PWR based on 5% 233U & 2.8% 231Pa, 6% 233U & 2.8% 231Pa and 7% 233U & 6% 231Pa give low excess reactivity

  3. Nuclear fuel cycle based on thorium and uranium-233

    International Nuclear Information System (INIS)

    The analysis of activities carried out in this country and abroad on a complex solution of principal problems of nuclear power advance. Demonstration of the potentiality of the above problems solution on the basis of conventional reactor plant development (light water cooled reactors and BN-type fast reactors) within the framework of nuclear fuel cycle using uranium-235, plutonium and uranium-233. 28 refs.; 1 fig.; 8 tabs

  4. Thorium utilization in a small long-life HTR. Part I: Th/U MOX fuel blocks

    International Nuclear Information System (INIS)

    Highlights: • We propose thorium MOX (TMOX) fuel blocks for a small block-type HTR. • The TMOX fuel blocks with low-enriched uranium are recommended. • More thorium decreases the reactivity swing of the TMOX fuel blocks. • Thorium reduces the negative temperature coefficient of the TMOX fuel blocks. • Thorium increases the conversion ratio of the TMOX fuel blocks. - Abstract: The U-Battery is a small, long-life and transportable high temperature gas-cooled reactor (HTR). The neutronic features of a typical fuel block with uranium and thorium have been investigated for a application of the U-Battery, by parametrically analyzing the composition and geometric parameters. The type of fuel block is defined as Th/U MOX fuel block because uranium and thorium are assumed to be mixed in each fuel kernel as a form of (Th,U)O2. If the initially loaded mass of U-235 is mostly consumed in the early period of the lifetime of Th/U MOX fuel block, low-enriched uranium (LEU) as ignited fuel will not largely reduce the neutronic performance of the Th/U MOX fuel block, compared with high-enriched uranium. The radii of fuel kernels and fuel compacts and packing fraction of TRISO particles determine the atomic ratio of the carbon to heavy metal. When the ratio is smaller than 400, the difference among them due to double heterogeneous effects can be neglected for the Th/U MOX fuel block. In the range between 200 and 400, the reactivity swing of the Th/U MOX fuel block during 10 years is sufficiently small. The magnitude of the negative reactivity temperature coefficients of the Th/U MOX fuel block decreases by 20–45%, which is positive to reduce temperature defect of the Th/U MOX fuel block. The conversion ratio (CR) of the fuel increases from 0.48 (typical CR of the LEU-fueled U-Battery) to 0.78. The larger conversion ratio of the Th/U MOX fuel block reduces the reactivity swing during 10 years for the U-Battery

  5. The utilisation of thorium fuel in a generation 4 light water reactor design

    International Nuclear Information System (INIS)

    During the last several years the Department of Energy has sponsored research at Purdue University on advanced reactor designs under the Nuclear Energy Research Initiative (NERI) programme. This work has involved research in 'Generation IV' advanced reactor designs such as a high conversion boiling water reactor, as well research in advanced fuel designs such a metal matrix 'dispersion' fuel. The unifying theme of this research has been to take advantage of the numerous benefits of the thorium fuel cycle. The Purdue research has been performed in collaboration with Argonne and Brookhaven National Laboratories for the dispersion fuel research and the high conversion reactor research, respectively. The primary contribution to both research efforts from Purdue has been on neutronics design and analysis. This paper will focus on the neutronics design and analysis of the high conversion boiling water reactor. (author)

  6. Implications of using alternate fuel cycles to meet Ontario's nuclear power demand

    International Nuclear Information System (INIS)

    The use of alternate fuel cycles to meet an assumed nuclear capacity growth rate in Ontario is examined. Two criteria are used: the ability of the alternate fuel cycles to lessen the uranium demand; and the ease of commercialization. The nuclear strategies considered assume the use of the natural uranium cycle and, starting in the year 2000, the gradual introduction of an alternate fuel cycle. The alternate fuel cycles reviewed are enriched uranium, mixed oxides, and a variety of thorium cycles. The cumulative uranium requirement to the year 2070, and the growth and size of the reprocessing and fuel fabrication industries are discussed in detail. Sensitivity analyses on nuclear capacity growth rate, recycling loss and delay time are also described. (auth)

  7. Used oil as a fuel oil alternative

    Energy Technology Data Exchange (ETDEWEB)

    Karaosmanoglu, F.; Beker, U.G. [Istanbul Technical Univ. (Turkey). Chemical Engineering Dept.

    1996-09-01

    In this study, the possibility of using used frying oil as a fuel oil alternative has been investigated. The fuel oil analysis tests applied to the reference fuel oil, used frying oil and its blends with fuel oil, were done according to standard test methods. The experimental results indicated that used frying oil and its blends with fuel oil can be proposed as a possible substitute for fuel oil.

  8. Romanian irradiation experiment on AHWR type fuel elements containing mixed oxide of thorium and uranium pellets

    International Nuclear Information System (INIS)

    One of the main objectives of the Institute for Nuclear Research (ICN) - Nuclear Fuel R and D Program is the development of new types of fuel based on: Slightly Enriched Uranium (SEU), Recycled Uranium (RU) and Thorium. Two experimental fuel elements (A23 and A24) were irradiated in TRIGA Research Reactor of ICN-Romania (C1 device) in a power ramp conditions. Element A23, contained mixed oxide of thorium and uranium pellets, achieved a maximum linear power of 51 KW/m and has reached a discharge burn-up around 189.2 MWh/KgHE; element A24, contained dioxide of uranium pellets, achieved a maximum linear power of 63 kW/m and has reached a discharge burn-up of around 207.8 MWh/KgHE. The experiments simulation has been performed using an improved version of ROFEM Code, version developed through the efforts of researchers from ICN - Nuclear Fuel Performance Department. The simulation results are in good agreement with experimental data. (author)

  9. Design study of Thorium-232 and Protactinium-231 based fuel for long life BWR

    Science.gov (United States)

    Trianti, N.; Su'ud, Z.; Riyana, E. S.

    2012-06-01

    A preliminary design study for the utilization of thorium added with 231Pa based fuel on BWR type reactor has been performed. In the previous research utilization of fuel based Thorium-232 and Uranium-233 show 10 years operation time with maximum excess-reactivity about 4.075% dk/k. To increase reactor operation time and reduce excess-reactivity below 1% dk/k, Protactinium (Pa-231) is used as Burnable Poison. Protactinium-231 has very interesting neutronic properties, which enable the core to reduce initial excess-reactivity and simultaneously increase production of 233U to 231Pa in burn-up process. Optimizations of the content of 231Pa in the core enables the BWR core to sustain long period of operation time with reasonable burn-up reactivity swing. Based on the optimization of fuel element composition (Th and Pa) in various moderation ratio we can get reactor core with longer operation time, 20 ˜ 30 years operation without fuel shuffling or refuelling, with average power densities maximum of about 35 watt/cc, and maximum excess-reactivity 0.56% dk/k.

  10. Optimization of the self-sufficient thorium fuel cycle for CANDU power reactors

    Directory of Open Access Journals (Sweden)

    Bergelson Boris R.

    2008-01-01

    Full Text Available The results of optimization calculations for CANDU reactors operating in the thorium cycle are presented in this paper. Calculations were performed to validate the feasibility of operating a heavy-water thermal neutron power reactor in a self-sufficient thorium cycle. Two modes of operation were considered in the paper: the mode of preliminary accumulation of 233U in the reactor itself and the mode of operation in a self-sufficient cycle. For the mode of accumulation of 233U, it was assumed that enriched uranium or plutonium was used as additional fissile material to provide neutrons for 233U production. In the self-sufficient mode of operation, the mass and isotopic composition of heavy nuclei unloaded from the reactor should provide (after the removal of fission products the value of the multiplication factor of the cell in the following cycle K>1. Additionally, the task was to determine the geometry and composition of the cell for an acceptable burn up of 233U. The results obtained demonstrate that the realization of a self-sufficient thorium mode for a CANDU reactor is possible without using new technologies. The main features of the reactor ensuring a self-sufficient mode of operation are a good neutron balance and moving of fuel through the active core.

  11. Fuel-cycle costs for alternative fuels

    International Nuclear Information System (INIS)

    This paper compares the fuel cycle cost and fresh fuel requirements for a range of nuclear reactor systems including the present day LWR without fuel recycle, an LWR modified to obtain a higher fuel burnup, an LWR using recycle uranium and plutonium fuel, an LWR using a proliferation resistant 233U-Th cycle, a heavy water reactor, a couple of HTGRs, a GCFR, and several LMFBRs. These reactor systems were selected from a set of 26 developed for the NASAP study and represent a wide range of fuel cycle requirements

  12. The radiological risks associated with the thorium fuelled HTGR fuel cycle. A comparative risk evaluation

    International Nuclear Information System (INIS)

    This report presents the results of task B.3 of the 'Technology Assessment of the High Temperature Reactor' project. The objective of task B.3 was to evaluate the radiological risks to the general public associated with the sustainable HTGR cycle. Since the technologies to be used at several stages of this fuel cycle are still in the design phase and since a detailed specification of this fuel cycle has not yet been developed, the emphasis was on obtaining a global impression of the risk associated with a generic thorium-based HTGR fuel cycle. This impression was obtained by performing a comparative risk analysis on the basis of data given in the literature. As reference for the comparison a generic uranium fuelled LWR cycle was used. The major benefit with respect to the radiological rsiks of basing the fuel cycle around modular HTGR technology instead of the LWR technology is the increase in reactor safety. The design of the modular HTGR is expected to prevent the release of a significant amount of radioactive material to the environment, and hence early deaths in the surrounding population, during accident conditions. This implies that there is no group risk as defined in the Dutch risk management policy. The major benefit of thorium based fuel cycles over uranium based fuel cycles is the reduction in the radiological risks from unraium mining and milling. The other stages of the nuclear fuel cycle which make a significant contribution to the radiological risks are electricity generation, reprocessing and final disposal. The risks associated with the electricity generation stage are dominated by the risks from fission products, activated corrosion products and the activation products tritium and carbon-14. The risks associated with the reprocessing stage are determined by fission and activation products (including actinides). (orig./WL)

  13. Alternatives to traditional transportation fuels 1993

    Energy Technology Data Exchange (ETDEWEB)

    1995-01-01

    In recent years, gasoline and diesel fuel have accounted for about 80 percent of total transportation fuel and nearly all of the fuel used in on-road vehicles. Growing concerns about the environmental effects of fossil fuel use and the Nation`s high level of dependence on foreign oil are providing impetus for the development of replacements or alternatives for these traditional transportation fuels. (The Energy Policy Act of 1992 definitions of {open_quotes}replacement{close_quotes} and {open_quotes}alternative{close_quotes} fuels are presented in the following box.) The Alternative Motor Fuels Act of 1988, the Clean Air Act Amendments of 1990 (CAAA90) and the Energy Policy Act of 1992 (EPACT) are significant legislative forces behind the growth of replacement fuel use. Alternatives to Traditional Transportation Fuels 1993 provides the number of on-road alternative fueled vehicles in use in the United States, alternative and replacement fuel consumption, and information on greenhouse gas emissions resulting from the production, delivery, and use of replacement fuels for 1992, 1993, and 1995.

  14. Complex reactor physics investigations of thorium containing liquid fuel

    International Nuclear Information System (INIS)

    The great progress in the development of new accelerators has substantially contributed to a new possibility of a practical solution of nuclear waste issue on the basis of transmutation. For an adoption of the given region of problems and a start of an own contribution to its solution in specific conditions of Czech nuclear power program, the first stage of investigation was performed in the Nuclear Research Institute Rez plc., the Nuclear Physics Institute of the Academy of Sciences of the Czech Republic and Research and Development Basis of the SKODA, Nuclear Machinery Ltd. with an assistance of the Czech Power Generating Board during the years 1994 -1996. Two special conferences were organized by their initiative in June 1994 and September 1995 which made an inventory of abilities and interests of Czech scientific, research and industrial institutions to take share in the solution of this problem. The construction of a nuclear power plant - transmuter, where the possibility to reach critical state is excluded and, simultaneously, the continuous separation of short-lived as well as of long-lived isotopes (including actinides) from the primary fuel-coolant circuit is made possible, is the goal. The key part of such a system will be, besides an accelerator and devices of a mechanical and chemical reprocessing, a subcritical reactor system containing a variety of fuel materials among them even Th containing components on which we have been focusing our work from the point of view of new proliferation resistant technologies. In the framework of the Czech national project of a transmuter called LA-0, there is a close collaboration assumed with a series of leading foreign laboratories with whom a very fruitful contacts have already been established. (author)

  15. Thorium fuel cycle in VBER reactor for floating nuclear power plants

    International Nuclear Information System (INIS)

    Construction of Floating Nuclear Power Plants, FNPPs, is currently under way for supplying power in remote regions in the coastal zone, power-generating units as components of nuclear water desalination complexes and for supplying power for marine oil drilling platforms, etc. In this paper the innovative small sized VBER-150 reactor plant, based on the experience in design and operation of marine modular reactors and NPPs with reactors of the VVER type, is reviewed and their neutron-physical characteristics for Thorium based fuel cycles are calculated with the well-known MCNP computational code. (Author)

  16. Alternate-Fueled Combustor-Sector Emissions

    Science.gov (United States)

    Saxena, Nikita T.; Thomas, Anna E.; Shouse, Dale T.; Neuroth, Craig; Hendricks, Robert C.; Lynch, Amy; Frayne, Charles W.; Stutrud, Jeffrey S.; Corporan, Edwin; Hankins, Terry

    2013-01-01

    In order to meet rapidly growing demand for fuel, as well as address environmental concerns, the aviation industry has been testing alternate fuels for performance and technical usability in commercial and military aircraft. In order to make alternate fuels (and blends) a viable option for aviation, the fuel must be able to perform at a similar or higher level than traditional petroleum fuel. They also attempt to curb harmful emissions, and therefore a truly effective alternate fuel would emit at or under the level of currently used fuel. This report analyzes data from gaseous and particulate emissions of an aircraft combustor sector. The data were evaluated at various inlet conditions, including variation in pressure and temperature, fuel-to-air ratios, and percent composition of alternate fuel. Traditional JP-8+100 data were taken as a baseline, and blends of JP-8+100 with synthetic-paraffinic-kerosene (SPK) fuel (Fischer-Tropsch (FT)) were used for comparison. Gaseous and particulate emissions, as well as flame luminosity, were assessed for differences between FT composition of 0, 50, and 100 percent. The data show that SPK fuel (an FT-derived fuel) had slightly lower harmful gaseous emissions, and smoke number information corroborated the hypothesis that SPK-FT fuels are cleaner burning fuels.

  17. Safety analysis of thorium-based fuels in the General Electric Standard BWR

    International Nuclear Information System (INIS)

    A denatured (U-233/Th)O2 fuel assembly has been designed which is energy equivalent to and hardware interchangeable with a modern boiling water reactor (BWR) reference reload assembly. Relative to the reference UO2 fuel, the thorium fuel design shows better performance during normal and transient reactor operation for the BWR/6 product line and will meet or exceed current safety and licensing criteria. Power distributions are flattened and thermal operating margins are increased by reduced steam void reactivity coefficients caused by U-233. However, a (U-233/Th)O2-fueled BWR will likely have reduced operating flexibility. A (U-235/Th)O2-fueled BWR should perform similar to a UO2-fueled BWR under all operating conditions. A (Pu/Th)O2-fueled BWR may have reduced thermal margins and similar accident response and be less stable than a UO2-fueled BWR. The assessment is based on comparisions of point model and infinite lattice predictions of various nuclear reactivity parameters, including void reactivity coefficients, Doppler reactivity coefficients, and control blade worths

  18. Commercial thorium fuel manufacture and irradiation: Testing (Th, Pu)O2 and (Th, U)O2 in the “Seven-Thirty” program

    International Nuclear Information System (INIS)

    Highlights: • Three different thorium containing fuel types are test irradiated. • Fuel temperatures, cladding elongation and rod pressures are monitored online. • Addition of 7% thorium to the uranium matrix lowers fuel temperatures. • Measurements also indicate lowered temperatures of thorium–plutonium MOX fuel. - Abstract: Thorium based fuels are being tested in the Halden Research Reactor in Norway with the aim of producing the data necessary for licensing of these fuels in today’s light water reactors. The fuel types currently under irradiation are thorium oxide fuel with plutonium as the fissile component, and uranium fuel with thorium as an additive for enhancement of thermo-mechanical and neutronic fuel properties. Fuel temperatures, rod pressures and dimensional changes are monitored on-line for quantification of thermo-mechanical behavior and fission gas release. Preliminary irradiation results show benefits in terms of lower fuel temperatures, mainly caused by improved thermal conductivity of the thorium fuels. In parallel with the irradiation, a manufacturing procedure for thorium–plutonium mixed oxide fuel is developed with the aim to manufacture industrially relevant high-quality fuel pellets for the next phase of the irradiation campaign

  19. Thermodynamic studies of thorium carbide fuel preparation and fuel/clad compatibility

    International Nuclear Information System (INIS)

    The carbothermic reduction of thorium and uranium-thorium dioxide to monocarbide has been assessed. Equilibrium calculations have yielded Th-C-O and U-Th-C-O phase equilibria and CO pressures generated during reduction. The CO pressures were found to be at least five orders of magnitude greater than any of the other 15 gaseous species considered. This confirms that the monocarbide can successfully be prepared by carbothermic reduction. The chemical compatibility of thorium carbides with the Cr-Fe-Ni content of clad alloys has been thermodynamically evaluated. Solid solutions of 5> and 5> and of 7C3> and 7C3> were the principal reaction products. The Cr-Fe-Ni content of 316 stainless steel showed much less reaction product than that of any of the other six alloys considered. (author)

  20. Thorium fuel utilization: Options and trends. Proceedings of three IAEA meetings held in Vienna in 1997, 1998 and 1999

    International Nuclear Information System (INIS)

    A series of three IAEA meetings on utilization of thorium fuel were held in Vienna over a period of three years, 1997-1999. The purpose of the meetings was to access the advantages, shortcomings and options of the thorium fuel under current conditions, with the aim of identifying new research areas and fields of possible co-operation within the framework of the IAEA Programme on Emerging Energy Systems. Apart from current commercial reactors, the scope of the meetings covered all types of evolutionary and innovative nuclear reactors, including molten salt reactors and hybrid systems. This document contains individual presentations delivered at the meetings. Each of the presentations was indexed separately

  1. Hybrid fusion-fission reactor with a thorium blanket: Its potential in the fuel cycle of nuclear reactors

    Science.gov (United States)

    Shmelev, A. N.; Kulikov, G. G.; Kurnaev, V. A.; Salahutdinov, G. H.; Kulikov, E. G.; Apse, V. A.

    2015-12-01

    Discussions are currently going on as to whether it is suitable to employ thorium in the nuclear fuel cycle. This work demonstrates that the 231Pa-232U-233U-Th composition to be produced in the thorium blanket of a hybrid thermonuclear reactor (HTR) as a fuel for light-water reactors opens up the possibility of achieving high, up to 30% of heavy metals (HM), or even ultrahigh fuel burnup. This is because the above fuel composition is able to stabilize its neutron-multiplying properties in the process of high fuel burnup. In addition, it allows the nuclear fuel cycle (NFC) to be better protected against unauthorized proliferation of fissile materials owing to an unprecedentedly large fraction of 232U (several percent!) in the uranium bred from the Th blanket, which will substantially hamper the use of fissile materials in a closed NFC for purposes other than power production.

  2. Hybrid fusion–fission reactor with a thorium blanket: Its potential in the fuel cycle of nuclear reactors

    International Nuclear Information System (INIS)

    Discussions are currently going on as to whether it is suitable to employ thorium in the nuclear fuel cycle. This work demonstrates that the 231Pa–232U–233U–Th composition to be produced in the thorium blanket of a hybrid thermonuclear reactor (HTR) as a fuel for light-water reactors opens up the possibility of achieving high, up to 30% of heavy metals (HM), or even ultrahigh fuel burnup. This is because the above fuel composition is able to stabilize its neutron-multiplying properties in the process of high fuel burnup. In addition, it allows the nuclear fuel cycle (NFC) to be better protected against unauthorized proliferation of fissile materials owing to an unprecedentedly large fraction of 232U (several percent!) in the uranium bred from the Th blanket, which will substantially hamper the use of fissile materials in a closed NFC for purposes other than power production

  3. Hybrid fusion–fission reactor with a thorium blanket: Its potential in the fuel cycle of nuclear reactors

    Energy Technology Data Exchange (ETDEWEB)

    Shmelev, A. N., E-mail: shmelan@mail.ru; Kulikov, G. G., E-mail: ggkulikov@mephi.ru; Kurnaev, V. A., E-mail: kurnaev@yandex.ru; Salahutdinov, G. H., E-mail: saip07@mail.ru; Kulikov, E. G., E-mail: egkulikov@mephi.ru; Apse, V. A., E-mail: apseva@mail.ru [National Research Nuclear University MEPhI (Moscow Engineering Physics Institute) (Russian Federation)

    2015-12-15

    Discussions are currently going on as to whether it is suitable to employ thorium in the nuclear fuel cycle. This work demonstrates that the {sup 231}Pa–{sup 232}U–{sup 233}U–Th composition to be produced in the thorium blanket of a hybrid thermonuclear reactor (HTR) as a fuel for light-water reactors opens up the possibility of achieving high, up to 30% of heavy metals (HM), or even ultrahigh fuel burnup. This is because the above fuel composition is able to stabilize its neutron-multiplying properties in the process of high fuel burnup. In addition, it allows the nuclear fuel cycle (NFC) to be better protected against unauthorized proliferation of fissile materials owing to an unprecedentedly large fraction of {sup 232}U (several percent!) in the uranium bred from the Th blanket, which will substantially hamper the use of fissile materials in a closed NFC for purposes other than power production.

  4. Irradiation performance and integrity of thorium oxide based coated particle fuels at high burnups

    International Nuclear Information System (INIS)

    In order to utilize thorium in a high temperature gas-cooled reactor (HTGR), a series of the irradiation experiments of thorium oxide based coated particle fuels have been conducted. This experiment is concerned with irradiation of the bonded TRISO- and BISO- coated (Th, U)O2 particles as fissile fuel in several variations of the Th/U ratios, U-235 enrichments, etc., and the bonded BISO- coated ThO2 particles as fertile fuel to investigate their integrity and irradiation behavior with three capsules in JMTR. Irradiation of these coated particles was achieved to a maximum neutron fluence of 2.22x1021n/cm2 (E>0.18MeV) at temperature of 1390degC, where the maximum burnup of the fissile particles was 7.3% FIMA. Both the fissile and fertile particles was 7.3% FIMA. Both the fissile and fertile particles were intact and performed well without coating failure, amoeba effect, and corrosion of the SiC layer by a fission product palladium. The data were also taken on irradiation-induced dimensional changes of the fuel compacts, failure fractions of the coated particles in these compacts measured by a newly developed acid leaching method, and on behavior of the irradiated coated fuel particles at extremely high temperatures (up to 2300degC) by an out-of-pile heating. Besides, the typical aspects of the amoeba effect were discussed on the coated particles which were irradiated in loosely-packed condition to compare irradiation performance with that for the bonded particles. (author)

  5. A Consistent Comparative Study of Advanced Sodium-cooled Fast Burner Cores loaded with Thorium and Uranium-based Metallic Fuels

    International Nuclear Information System (INIS)

    We considered uranium-based metallic fuel of TRU-U-10Zr for driver fuel and thorium was considered as blanket because thorium blanket produces less amount of TRU than uranium blanket and use of thorium blanket leads to smaller sodium void worth than the use of uranium blanket due to the fact that the η-value increases much less with energy for 233U than for 239Pu and 232Th is less fissile than 238U. However, these cores using thorium blanket still have a large amount of TRU production from the driver fuels because the driver fuels contain a large amount of depleted uranium which leads to the production of TRU through neutron capture. The objective of this work is to consistently compare the neutronic performances of advanced sodium cooled fast reactor cores loaded with thorium and uraniumbased metallic fuels as driver fuel for TRU burning. Our main emphasis is given on the analyses of the differences in the core performance parameters. For consistent comparison, we used the same core configuration and all the same design parameters except for the fact that depleted uranium in uraniumbased fuel is replaced with thorium. We considered the cores having no thorium blanket and the cores having thorium blanket that were designed in our previous works

  6. Sulphur release from alternative fuel firing

    DEFF Research Database (Denmark)

    Cortada Mut, Maria del Mar; Nørskov, Linda Kaare; Glarborg, Peter;

    2014-01-01

    The cement industry has long been dependent on the use of fossil fuels, although a recent trend in replacing fossil fuels with alternative fuels has arisen. 1, 2 However, when unconverted or partly converted alternative fuels are admitted directly in the rotary kiln inlet, the volatiles released...... from the fuels may react with sulphates present in the hot meal to form SO 2 . Here Maria del Mar Cortada Mut and associates describe pilot and industrial scale experiments focusing on the factors that affect SO 2 release in the cement kiln inlet....

  7. Standardization of Alternative Fuels. Phase 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-08-15

    There are different interpretations of the term 'alternative fuels', depending on the part of the world in which the definition is used. In this report, alternative fuels mainly stand for fuels that can replace gasoline and diesel oil and at the same time contribute to lowered emissions with impact on health, environment and climate. The use of alternative vehicle fuels has increased during the last 30 years. However, the increase has developed slowly and today the use is very limited, compared to the use of conventional fuels. Although, the use in some special applications, often in rather small geographical areas, can be somewhat larger. The main interest for alternative fuels has for a long time been driven by supply security issues and the possibility to reduce emissions with a negative impact on health and environment. However, the development of reformulated gasoline and low sulphur diesel oil has contributed to substantially decreased emissions from these fuels without using any alternative fuel. This has reduced the environmental impact driving force for the introduction of alternative fuels. In line with the increased interest for climate effects and the connections between these effects and the emission of greenhouse gases, and then primarily carbon dioxide, the interest for biomass based alternative fuels has increased during the 1990s. Even though one of the driving forces for alternative fuels is small today, alternative fuels are more commonly accepted than ever before. The European Commission has for example in May 2003 agreed on a directive for the promotion of the use of bio fuels. In the directive there are goals for the coming 7 years that will increase the use of alternative fuels in Europe rather dramatically, from below 1 percent now up to almost 6 percent of the total vehicle fuel consumption in 2010. The increased use of alternative fuels in Europe and the rest of the world will create a need for a common interpretation of what we

  8. Core loading pattern optimization of thorium fueled heavy water breeder reactor using genetic algorithm

    International Nuclear Information System (INIS)

    In this work genetic algorithm was proposed to solve fuel loading pattern optimization problem in thorium fueled heavy water reactor. The objective function of optimization was to maximize the conversion ratio and minimize power peaking factor. Those objectives were simultaneously optimized using non-dominated Pareto-based population ranking optimal method. Members of non-dominated population were assigned selection probabilities based on their rankings in a manner similar to Baker's single criterion ranking selection procedure. A selected non-dominated member was bred through simple mutation or one-point crossover process to produce a new member. The genetic algorithm program was developed in FORTRAN 90 while neutronic calculation and analysis was done by COREBN code, a module of core burn-up calculation for SRAC. (authors)

  9. Utilisation of thorium in reactors

    Science.gov (United States)

    Anantharaman, K.; Shivakumar, V.; Saha, D.

    2008-12-01

    India's nuclear programme envisages a large-scale utilisation of thorium, as it has limited deposits of uranium but vast deposits of thorium. The large-scale utilisation of thorium requires the adoption of closed fuel cycle. The stable nature of thoria and the radiological issues associated with thoria poses challenges in the adoption of a closed fuel cycle. A thorium fuel based Advanced Heavy Water Reactor (AHWR) is being planned to provide impetus to development of technologies for the closed thorium fuel cycle. Thoria fuel has been loaded in Indian reactors and test irradiations have been carried out with (Th-Pu) MOX fuel. Irradiated thorium assemblies have been reprocessed and the separated 233U fuel has been used for test reactor KAMINI. The paper highlights the Indian experience with the use of thorium and brings out various issues associated with the thorium cycle.

  10. Chemistry in the front end and back end of thorium fuel cycle

    International Nuclear Information System (INIS)

    Microsphere impregnation technique has been developed for fabrication of Thoria based fuels in Fuel Chemistry Division. The process optimization was carried out to get homogeneous distribution of uranium in thoria. A simple and fast method for the dissolution of sintered ThO2 and (UxTh1-x)O2 (sintered at 1600-1700°C and with approx. 94% of the theoretical density) and separation of thorium and uranium from the solution was developed by reacting the oxides with ammonium nitrate at 360°C. Analytical method was developed for determination of relative amounts of U and Th in MOX by using TXRF method. Extensive studies on phase diagram and thermophysical properties of thoria based fuels were carried out in a wide composition and temperature range. For reprocessing studies, a large number of amides (12 nos.) was evaluated for their extraction behavior with respect to U/Th separation and it was concluded that branched alkyl chain amide, di-2-ethylhexyl isobutyramide (D2EHIBA), is a promising candidate for the selective separation of 233U from irradiated Th. Thermal and thermodynamic stability of Phosphate based inert matrix was also studied for its application for waste immobilization of thoria based fuels. With respect to molten salt reactor system, thermal behavior, thermodynamic properties and phase diagrams of Th-F, U-F, Th-U-F, Th-O-F systems were investigated. A high temperature and hydroflourination facility has been set up for preparation and purification of thorium based fluoride salts. This lecture will address some of the developments in the above field of research carried out in Radiochemistry and Isotope Group of BARC

  11. Optimization of Heterogeneous Fuel Designs for Utilization of Thorium In PWRs To Enhance Proliferation Resistance and Reduce Waste

    International Nuclear Information System (INIS)

    This paper presents a summary of the first stage of the project aimed to examine heterogeneous core design options for the implementation of the thorium-233U fuel cycle in pressurized water reactors (PWRs) and to identify the core design and fuel management strategies that will maximize the benefits from inclusion of thorium in the fuel. The project is carried out within a framework of Nuclear Energy Research Initiative (NERI) supported by the US Department of Energy (1). Principal investigators are M. Todosow from Brookhaven National Laboratory and M. Kazimi from Massachusetts Institute of Technology with contributions from Kurchatov Institute (Russia) and Ben-Gurion University of the Negev (Israel). The fuel cycle assessment concentrates on key measures of performance in several important areas including proliferation characteristics of the spent fuel, reliability, safety, cost, environmental impact, and licensing issues

  12. Analysis on specific nuclear data for reactors physics computations applied to CANDU reactors using thorium-based fuels

    International Nuclear Information System (INIS)

    The purpose of this work is to analyze the evaluated nuclear data from ENDF libraries IAEA69 (69 energy groups library) and IAEA172 (172 energy groups library), respectively, in WIMS library format and to represent neutron fission yield, absorption and fission cross-section dependence for 233Uranium, 232Thorium isotopes and some actinides of interest on the incident energy. Our interest for these two isotopes is mainly based on the importance of 233Uranium as 'fissile nucleus' in Thorium-Uranium fuel cycle. Nowadays, nuclear data evaluation for the actinides generated in Thorium-Uranium fuel cycle is seen as a world-wide priority. The fissile nucleus, 233Uranium 'plays' the same function in Thorium-Uranium fuel cycle as the 235Uranium in 'the classic' Uranium-Plutonium fuel cycle. As opposed to natural Uranium which contains 0.7 % of the fissile isotope 235Uranium, natural Thorium doesn't contain fissile isotopes, being composed entirely by the fertile isotope 232Thorium. Graphical evolutions of interest parameters versus the incident energy are presented. Our interest was also to observe the behavior of these nuclear data for fast, resonance and thermal energy groups, respectively. The ENDF nuclear data libraries are constantly up-dated, so that we can observe an improvement of the IAEA172 library, which disposes of evaluated nuclear data at higher energies (about 20 MeV), as opposed to IAEA69 library (which includes evaluated nuclear data below 10 MeV). Based on our graphical representation, a good agreement between the considered libraries has been observed, sustaining nuclear data validity. (authors)

  13. Impact of thorium based molten salt reactor on the closure of the nuclear fuel cycle

    Science.gov (United States)

    Jaradat, Safwan Qasim Mohammad

    Molten salt reactor (MSR) is one of six reactors selected by the Generation IV International Forum (GIF). The liquid fluoride thorium reactor (LFTR) is a MSR concept based on thorium fuel cycle. LFTR uses liquid fluoride salts as a nuclear fuel. It uses 232Th and 233U as the fertile and fissile materials, respectively. Fluoride salt of these nuclides is dissolved in a mixed carrier salt of lithium and beryllium (FLiBe). The objective of this research was to complete feasibility studies of a small commercial thermal LFTR. The focus was on neutronic calculations in order to prescribe core design parameter such as core size, fuel block pitch (p), fuel channel radius, fuel path, reflector thickness, fuel salt composition, and power. In order to achieve this objective, the applicability of Monte Carlo N-Particle Transport Code (MCNP) to MSR modeling was verified. Then, a prescription for conceptual small thermal reactor LFTR and relevant calculations were performed using MCNP to determine the main neutronic parameters of the core reactor. The MCNP code was used to study the reactor physics characteristics for the FUJI-U3 reactor. The results were then compared with the results obtained from the original FUJI-U3 using the reactor physics code SRAC95 and the burnup analysis code ORIPHY2. The results were comparable with each other. Based on the results, MCNP was found to be a reliable code to model a small thermal LFTR and study all the related reactor physics characteristics. The results of this study were promising and successful in demonstrating a prefatory small commercial LFTR design. The outcome of using a small core reactor with a diameter/height of 280/260 cm that would operate for more than five years at a power level of 150 MWth was studied. The fuel system 7LiF - BeF2 - ThF4 - UF4 with a (233U/ 232Th) = 2.01 % was the candidate fuel for this reactor core.

  14. Implementation barriers of alternative transport fuels

    Energy Technology Data Exchange (ETDEWEB)

    Troelstra, W.P. [Innas, Breda (Netherlands); Smith, A. [AEA Technology, London (United Kingdom); Bol, M. [Sypher Mueller International, Morristown, New Jersey (United Kingdom)

    1999-02-01

    The study on the title subject aims to present an overview of the practical barriers associated with the introduction of alternative fuels for transport applications in IEA countries. The aim is to provide an information source to which potential users can refer when deciding whether to introduce an alternative fuel. The report will highlight potential problems so that users can either select the alternative fuel best suited to their needs, or implement possible solutions to the problems. The study covers natural gas (both compressed (CNG) and liquefied (LNG)), LPG (liquefied petroleum gas), ethanol (mainly bio-ethanol), methanol, bio-diesel, hydrogen, DME(dimethyl ether), and electricity. 48 refs.

  15. Implementation barriers of alternative transport fuels

    International Nuclear Information System (INIS)

    The study on the title subject aims to present an overview of the practical barriers associated with the introduction of alternative fuels for transport applications in IEA countries. The aim is to provide an information source to which potential users can refer when deciding whether to introduce an alternative fuel. The report will highlight potential problems so that users can either select the alternative fuel best suited to their needs, or implement possible solutions to the problems. The study covers natural gas (both compressed (CNG) and liquefied (LNG)), LPG (liquefied petroleum gas), ethanol (mainly bio-ethanol), methanol, bio-diesel, hydrogen, DME(dimethyl ether), and electricity. 48 refs

  16. Thermal hydraulic analysis of thorium fuel assemblies loaded with annular seed pins

    International Nuclear Information System (INIS)

    Thermal hydraulic characteristics of thorium-based fuel assemblies loaded with annular seed pins have been analyzed using MATRAA combined with MATRA, and compared with those of the existing thorium-based assemblies. MATRA and MATRAA showed good agreements for the pressure drops at the internal subchannels. The pressure drop generally increased in the cases of the assemblies loaded with annular seed pins due to the larger wetted perimeter, but an exception existed. In the inner subchannels of the seed pins, mass fluxes were high due to the grid form losses in the outer subchannels. About 43% of the heat generated from the seed pin flowed into the inner subchannel and the rest into the outer subchannel, which implies the inner to outer wall heat flux ratio was approximately 1.2. The maximum temperatures of the annular seed pins were slightly above 500 qC. The MDNBRs of the assemblies loaded with annular seed pins were higher than those of the existing assemblies. Due to the fact that interchannel mixing cannot occur in the inner subchannels, temperatures and enthalpies were higher in the inner subchannels

  17. Online fuel failure detection and damage severity analysis for thorium based AHWR fuel matrix - an empirical analysis

    International Nuclear Information System (INIS)

    A clad failure, results in the escape of fission products from the fuel to coolant. Continued operation of the reactor with the presence of failed fuel would cause excessive radioactive contamination of the Main Heat Transport (MHT) system and its associated components. Therefore online detection and precise location of failed fuel in the core is necessary for the safe and healthy operation of the reactor and to reduce the man-rem exposure. For the development of online system for iodine and gaseous fission product monitoring for AHWR, an empirical analysis was carried out to compute these fission product release rate data for thorium based AHWR mix-oxide fuel consisting of (Th-233U)O2 and (Th-Pu)O2. The release rate and activity concentration rates in the coolant were calculated for various types of fuel failures and a feasibility study was carried out for online gaseous fission product and iodine monitoring using HPGe detector and high resolution gamma ray spectrometer system. Further, this paper also discusses the different methodologies for identifying severity of fuel damage. (author)

  18. Emerging trends in alternative aviation fuels

    Science.gov (United States)

    Corbett, Cody

    The days of petroleum-based aviation fuels are numbered. New regulations to be set in place in the coming years will force current fuels to be phased out in favor of cleaner fuels with less toxic emissions. The alternative fuel industry has already taken its foothold in other modes of transportation, and aviation will soon follow suit. Many companies have cropped up over the last decade, and a few have been around longer, that work hard to develop the alternative aviation fuels of the future. It is important, however, for the aviation community to know what to expect and when to expect it concerning alternative fuels. This study investigates where various companies in the alternative aviation fuel industry currently stand in their development and production processes, and how their products will affect aircraft owners and operators. By interviewing representatives from these companies and analyzing their responses to identify trends, an educated prediction can be made about where the industry is headed and when the aviation community can expect these fuel to be available. The findings of this study indicate that many companies are still in their developmental stages, with a few notable outliers, and that most of these companies expect to see production of their product by 2017. Also, the fuel manufacturers are dealing with all the legal hurdles regarding alternative fuels, so little to no effort will be required on the part of the consumer. These findings, along with their analysis, will enable the aviation community to make educated decisions concerning fuel and their aircraft, as well and do their part to help these beneficial fuels get to market.

  19. Proceedings of the 1993 Windsor Workshop on Alternative Fuels

    Energy Technology Data Exchange (ETDEWEB)

    1993-10-01

    This report contains viewgraph papers on the following topics on alternative fuels: availability of alternative fueled engines and vehicles; emerging technologies; overcoming barriers to alternative fuels commercialization; infrastructure issues; and new initiatives in research and development.

  20. Global Energy Issues and Alternate Fueling

    Science.gov (United States)

    Hendricks, Robert C.

    2007-01-01

    This viewgraph presentation describes world energy issues and alternate fueling effects on aircraft design. The contents include: 1) US Uses about 100 Quad/year (1 Q = 10(exp 15) Btu) World Energy Use: about 433 Q/yr; 2) US Renewable Energy about 6%; 3) Nuclear Could Grow: Has Legacy Problems; 4) Energy Sources Primarily NonRenewable Hydrocarbon; 5) Notes; 6) Alternate Fuels Effect Aircraft Design; 7) Conventional-Biomass Issue - Food or Fuel; 8) Alternate fuels must be environmentally benign; 9) World Carbon (CO2) Emissions Problem; 10) Jim Hansen s Global Warming Warnings; 11) Gas Hydrates (Clathrates), Solar & Biomass Locations; 12) Global Energy Sector Response; 13) Alternative Renewables; 14) Stratospheric Sulfur Injection Global Cooling Switch; 15) Potential Global Energy Sector Response; and 16) New Sealing and Fluid Flow Challenges.

  1. Alternative motor fuels today and tomorrow

    Energy Technology Data Exchange (ETDEWEB)

    Bensaid, B

    2004-07-01

    Today, petroleum products account for 97% of the energy consumed in road transport. The purpose of replacing these products with alternative energies is to reduce oil dependence as well as greenhouse gas emissions. The high price of oil has promoted the use of 'conventional' alternative motor fuels (biofuels, LPG, NGV) and also renewed interest in syn-fuels (GTL, CTL, BTL) that have already given rise to industrial and pilot projects. (author)

  2. Alternative motor fuels today and tomorrow

    International Nuclear Information System (INIS)

    Today, petroleum products account for 97% of the energy consumed in road transport. The purpose of replacing these products with alternative energies is to reduce oil dependence as well as greenhouse gas emissions. The high price of oil has promoted the use of 'conventional' alternative motor fuels (biofuels, LPG, NGV) and also renewed interest in syn-fuels (GTL, CTL, BTL) that have already given rise to industrial and pilot projects. (author)

  3. Analysis of Burnup and Economic Potential of Alternative Fuel Materials in Thermal Reactors

    International Nuclear Information System (INIS)

    A strategy is proposed for the assessment of nuclear fuel material economic potential use in future light water reactors (LWRs). In this methodology, both the required enrichment and the fuel performance limits are considered. In order to select the best fuel candidate, the optimal burnup that produces the lowest annual fuel cost within the burnup potential for a given fuel material and smear density ratio is determined.Several nuclear materials are presented as examples of the application of the methodology proposed in this paper. The alternative fuels considered include uranium dioxide (UO2), uranium carbide (UC), uranium nitride (UN), metallic uranium (U-Zr alloy), combined thorium and uranium oxides (ThO2/UO2), and combined thorium and uranium metals (U/Th). For these examples, a typical LWR lattice geometry in a zirconium-based cladding was assumed. The uncertainties in the results presented are large due to the scarcity of experimental data regarding the behavior of the considered materials at high burnups. Also, chemical compatibility issues are to be considered separately.The same methodology can be applied in the future to evaluate the economic potential of other nuclear fuel materials including different cladding designs, dispersions of ceramics into ceramics, dispersions of ceramics into metals, and also for geometries other than the traditional circular fuel pin

  4. The feasibility study of small long-life gas cooled fast reactor with mixed natural Uranium/Thorium as fuel cycle input

    Science.gov (United States)

    Ariani, Menik; Su'ud, Zaki; Waris, Abdul; Khairurrijal, Monado, Fiber; Sekimoto, Hiroshi

    2012-06-01

    A conceptual design study of Gas Cooled Fast Reactors with Modified CANDLE burn-up scheme has been performed. In this study, design GCFR with Helium coolant which can be continuously operated by supplying mixed Natural Uranium/Thorium without fuel enrichment plant or fuel reprocessing plant. The active reactor cores are divided into two region, Thorium fuel region and Uranium fuel region. Each fuel core regions are subdivided into ten parts (region-1 until region-10) with the same volume in the axial direction. The fresh Natural Uranium and Thorium is initially put in region-1, after one cycle of 10 years of burn-up it is shifted to region-2 and the each region-1 is filled by fresh natural Uranium/Thorium fuel. This concept is basically applied to all regions in both cores area, i.e. shifted the core of ith region into i+1 region after the end of 10 years burn-up cycle. For the next cycles, we will add only Natural Uranium and Thorium on each region-1. The calculation results show the reactivity reached by mixed Natural Uranium/Thorium with volume ratio is 4.7:1. This reactor can results power thermal 550 MWth. After reactor start-up the operation, furthermore reactor only needs Natural Uranium/Thorium supply for continue operation along 100 years.

  5. A methodology for assessing the market benefits of alternative motor fuels: The Alternative Fuels Trade Model

    Energy Technology Data Exchange (ETDEWEB)

    Leiby, P.N.

    1993-09-01

    This report describes a modeling methodology for examining the prospective economic benefits of displacing motor gasoline use by alternative fuels. The approach is based on the Alternative Fuels Trade Model (AFTM). AFTM development was undertaken by the US Department of Energy (DOE) as part of a longer term study of alternative fuels issues. The AFTM is intended to assist with evaluating how alternative fuels may be promoted effectively, and what the consequences of substantial alternative fuels use might be. Such an evaluation of policies and consequences of an alternative fuels program is being undertaken by DOE as required by Section 502(b) of the Energy Policy Act of 1992. Interest in alternative fuels is based on the prospective economic, environmental and energy security benefits from the substitution of these fuels for conventional transportation fuels. The transportation sector is heavily dependent on oil. Increased oil use implies increased petroleum imports, with much of the increase coming from OPEC countries. Conversely, displacement of gasoline has the potential to reduce US petroleum imports, thereby reducing reliance on OPEC oil and possibly weakening OPEC`s ability to extract monopoly profits. The magnitude of US petroleum import reduction, the attendant fuel price changes, and the resulting US benefits, depend upon the nature of oil-gas substitution and the supply and demand behavior of other world regions. The methodology applies an integrated model of fuel market interactions to characterize these effects.

  6. Alternative Fuels and Chemicals from Synthesis Gas

    Energy Technology Data Exchange (ETDEWEB)

    Peter Tijrn

    2003-01-02

    The overall objectives of this program are to investigate potential technologies for the conversion of synthesis gas to oxygenated and hydrocarbon fuels and industrial chemicals, and to demonstrate the most promising technologies at DOE's LaPorte, Texas, Slurry Phase Alternative Fuels Development Unit (AFDU). The program will involve a continuation of the work performed under the Alternative Fuels from Coal-Derived Synthesis Gas Program and will draw upon information and technologies generated in parallel current and future DOE-funded contracts.

  7. ALTERNATIVE FUELS AND CHEMICALS FROM SYNTHESIS GAS

    Energy Technology Data Exchange (ETDEWEB)

    Peter Tijrn

    2003-02-03

    The overall objectives of this program are to investigate potential technologies for the conversion of synthesis gas to oxygenated and hydrocarbon fuels and industrial chemicals, and to demonstrate the most promising technologies at DOE's LaPorte, Texas, Slurry Phase Alternative Fuels Development Unit (AFDU). The program will involve a continuation of the work performed under the Alternative Fuels from Coal-Derived Synthesis Gas Program and will draw upon information and technologies generated in parallel current and future DOE-funded contracts.

  8. Alternative fuels and chemicals from synthesis gas

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    1998-08-01

    The overall objectives of this program are to investigate potential technologies for the conversion of synthesis gas to oxygenated and hydrocarbon fuels and industrial chemicals, and to demonstrate the most promising technologies at DOE's LaPorte, Texas, Slurry Phase Alternative Fuels Development Unit (AFDU). The program will involve a continuation of the work performed under the Alternative Fuels from Coal-Derived Synthesis Gas Program and will draw upon information and technologies generated in parallel current and future DOE-funded contracts.

  9. ALTERNATIVE FUELS AND CHEMICALS FROM SYNTHESIS GAS

    Energy Technology Data Exchange (ETDEWEB)

    Peter J. Tijrn

    2000-09-30

    The overall objectives of this program are to investigate potential technologies for the conversion of synthesis gas to oxygenated and hydrocarbon fuels and industrial chemicals, and to demonstrate the most promising technologies at DOE's LaPorte, Texas, Slurry Phase Alternative Fuels Development Unit (AFDU). The program will involve a continuation of the work performed under the Alternative Fuels from Coal-Derived Synthesis Gas Program and will draw upon information and technologies generated in parallel current and future DOE-funded contracts.

  10. ALTERNATIVE FUELS AND CHEMICALS FROM SYNTHESIS GAS

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    2001-03-31

    The overall objectives of this program are to investigate potential technologies for the conversion of synthesis gas to oxygenated and hydrocarbon fuels and industrial chemicals, and to demonstrate the most promising technologies at DOE's LaPorte, Texas, Slurry Phase Alternative Fuels Development Unit (AFDU). The program will involve a continuation of the work performed under the Alternative Fuels from Coal-Derived Synthesis Gas Program and will draw upon information and technologies generated in parallel current and future DOE-funded contracts.

  11. ALTERNATIVE FUELS AND CHEMICALS FROM SYNTHESIS GAS

    Energy Technology Data Exchange (ETDEWEB)

    Peter J. Tijrn

    2000-06-30

    The overall objectives of this program are to investigate potential technologies for the conversion of synthesis gas to oxygenated and hydrocarbon fuels and industrial chemicals, and to demonstrate the most promising technologies at DOE's LaPorte, Texas, Slurry Phase Alternative Fuels Development Unit (AFDU). The program will involve a continuation of the work performed under the Alternative Fuels from Coal-Derived Synthesis Gas Program and will draw upon information and technologies generated in parallel current and future DOE-funded contracts.

  12. ALTERNATIVE FUELS AND CHEMICALS FROM SYNTHESIS GAS

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-10-01

    The overall objectives of this program are to investigate potential technologies for the conversion of synthesis gas to oxygenated and hydrocarbon fuels and industrial chemicals, and to demonstrate the most promising technologies at DOE's LaPorte, Texas, Slurry Phase Alternative Fuels Development Unit (AFDU). The program will involve a continuation of the work performed under the Alternative Fuels from Coal-Derived Synthesis Gas Program and will draw upon information and technologies generated in parallel current and future DOE-funded contracts.

  13. ALTERNATIVE FUELS AND CHEMICALS FROM SYNTHESIS GAS

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    1999-07-01

    The overall objectives of this program are to investigate potential technologies for the conversion of synthesis gas to oxygenated and hydrocarbon fuels and industrial chemicals, and to demonstrate the most promising technologies at DOE's LaPorte, Texas, Slurry Phase Alternative Fuels Development Unit (AFDU). The program will involve a continuation of the work performed under the Alternative Fuels from Coal-Derived Synthesis Gas Program and will draw upon information and technologies generated in parallel current and future DOE-funded contracts.

  14. ALTERNATIVE FUELS AND CHEMICALS FROM SYNTHESIS GAS

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    2002-07-01

    The overall objectives of this program are to investigate potential technologies for the conversion of synthesis gas to oxygenated and hydrocarbon fuels and industrial chemicals, and to demonstrate the most promising technologies at DOE's LaPorte, Texas, Slurry Phase Alternative Fuels Development Unit (AFDU). The program will involve a continuation of the work performed under the Alternative Fuels from Coal-Derived Synthesis Gas Program and will draw upon information and technologies generated in parallel current and future DOE-funded contracts.

  15. ALTERNATIVE FUELS AND CHEMICALS FROM SYNTHESIS GAS

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    1999-04-01

    The overall objectives of this program are to investigate potential technologies for the conversion of synthesis gas to oxygenated and hydrocarbon fuels and industrial chemicals, and to demonstrate the most promising technologies at DOE's LaPorte, Texas, Slurry Phase Alternative Fuels Development Unit (AFDU). The program will involve a continuation of the work performed under the Alternative Fuels from Coal-Derived Synthesis Gas Program and will draw upon information and technologies generated in parallel current and future DOE-funded contracts.

  16. ALTERNATIVE FUELS AND CHEMICALS FROM SYNTHESIS GAS

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    2000-10-01

    The overall objectives of this program are to investigate potential technologies for the conversion of synthesis gas to oxygenated and hydrocarbon fuels and industrial chemicals, and to demonstrate the most promising technologies at DOE's LaPorte, Texas, Slurry Phase Alternative Fuels Development Unit (AFDU). The program will involve a continuation of the work performed under the Alternative Fuels from Coal-Derived Synthesis Gas Program and will draw upon information and technologies generated in parallel current and future DOE-funded contracts.

  17. ALTERNATIVE FUELS AND CHEMICALS FROM SYNTHESIS GAS

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    1998-01-01

    The overall objectives of this program are to investigate potential technologies for the conversion of synthesis gas to oxygenated and hydrocarbon fuels and industrial chemicals, and to demonstrate the most promising technologies at DOE's LaPorte, Texas, Slurry Phase Alternative Fuels Development Unit (AFDU). The program will involve a continuation of the work performed under the Alternative Fuels from Coal-Derived Synthesis Gas Program and will draw upon information and technologies generated in parallel current and future DOE-funded contracts.

  18. ALTERNATIVE FUELS AND CHEMICALS FROM SYNTHESIS GAS

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    1999-01-01

    The overall objectives of this program are to investigate potential technologies for the conversion of synthesis gas to oxygenated and hydrocarbon fuels and industrial chemicals, and to demonstrate the most promising technologies at DOE's LaPorte, Texas, Slurry Phase Alternative Fuels Development Unit (AFDU). The program will involve a continuation of the work performed under the Alternative Fuels from Coal-Derived Synthesis Gas Program and will draw upon information and technologies generated in parallel current and future DOE-funded contracts.

  19. Alternative Fuels and Chemicals From Synthesis Gas

    Energy Technology Data Exchange (ETDEWEB)

    none

    1998-07-01

    The overall objectives of this program are to investigate potential technologies for the conversion of synthesis gas to oxygenated and hydrocarbon fuels and industrial chemicals, and to demonstrate the most promising technologies at DOE's LaPorte, Texas, Slurry Phase Alternative Fuels Development Unit (AFDU). The program will involve a continuation of the work performed under the Alternative Fuels from Coal-Derived Synthesis Gas Program and will draw upon information and technologies generated in parallel current and future DOE-funded contracts.

  20. Thorium and its future importance for nuclear energy generation

    Energy Technology Data Exchange (ETDEWEB)

    Lainetti, Paulo E.O., E-mail: lainetti@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    Thorium was discovered in 1828 by the Swedish chemist Jons J. Berzelius. Despite some advantages over uranium for use in nuclear reactors, its main use, in the almost two centuries since its discovery, the use of thorium was restricted to use for gas mantles, especially in the early twentieth century. In the beginning of the Nuclear Era, many countries had interested on thorium, particularly during the 1950-1970 period. There are about 435 nuclear reactors in the world nowadays. They need more than 65.000 tons of uranium yearly. The future world energy needs will increase and, even if we assumed a conservative contribution of nuclear generation, it will be occur a significant increasing in the uranium prices, taking into account that uranium, as used in the present thermal reactors, is a finite resource. Thorium is nearly three times more abundant than uranium in the Earth's crust. Despite thorium is not a fissile material, {sup 232}Th can be converted to {sup 233}U (fissile) more efficiently than {sup 238}U to {sup 239}Pu. Besides this, since it is possible to convert thorium waste into nonradioactive elements, thorium is an environment-friendly alternative energy source. Thorium fuel cycle is also inherently resistant to proliferation. Some papers evaluate the thorium resources in Brazil over 1.200.000 metric t. Then, the thorium alternative must be seriously considered in Brazil for strategic reasons. In this paper a brief history of thorium is presented, besides a review of the world thorium utilization and a discussion about advantages and restrictions of thorium use. (author)

  1. Alternative Fuels and Sustainable Development

    DEFF Research Database (Denmark)

    Jørgensen, Kaj; Nielsen, Lars Henrik

    1996-01-01

    The main report of the project on Transportation Fuels based on Renewable Energy. The report contains a review of potential technologies for electric, hybrid and hydrogen propulsion in the Danish transport sector, including an assessment of their development status. In addition, the energy and...

  2. Burn-up calculation of different thorium-based fuel matrixes in a thermal research reactor using MCNPX 2.6 code

    Directory of Open Access Journals (Sweden)

    Gholamzadeh Zohreh

    2014-12-01

    Full Text Available Decrease of the economically accessible uranium resources and the inherent proliferation resistance of thorium fuel motivate its application in nuclear power systems. Estimation of the nuclear reactor’s neutronic parameters during different operational situations is of key importance for the safe operation of nuclear reactors. In the present research, thorium oxide fuel burn-up calculations for a demonstrative model of a heavy water- -cooled reactor have been performed using MCNPX 2.6 code. Neutronic parameters for three different thorium fuel matrices loaded separately in the modelled thermal core have been investigated. 233U, 235U and 239Pu isotopes have been used as fissile element in the thorium oxide fuel, separately. Burn-up of three different fuels has been calculated at 1 MW constant power. 135X and 149Sm concentration variations have been studied in the modelled core during 165 days burn-up. Burn-up of thorium oxide enriched with 233U resulted in the least 149Sm and 135Xe productions and net fissile production of 233U after 165 days. The negative fuel, coolant and void reactivity of the used fuel assures safe operation of the modelled thermal core containing (233U-Th O2 matrix. Furthermore, utilisation of thorium breeder fuel demonstrates several advantages, such as good neutronic economy, 233U production and less production of long-lived α emitter high radiotoxic wastes in biological internal exposure point of view

  3. Outlook for alternative energy sources. [aviation fuels

    Science.gov (United States)

    Card, M. E.

    1980-01-01

    Predictions are made concerning the development of alternative energy sources in the light of the present national energy situation. Particular emphasis is given to the impact of alternative fuels development on aviation fuels. The future outlook for aircraft fuels is that for the near term, there possibly will be no major fuel changes, but minor specification changes may be possible if supplies decrease. In the midterm, a broad cut fuel may be used if current development efforts are successful. As synfuel production levels increase beyond the 1990's there may be some mixtures of petroleum-based and synfuel products with the possibility of some shale distillate and indirect coal liquefaction products near the year 2000.

  4. Outlook on Standardization of Alternative Vehicle Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Rehnlund, B. [Atrax Energi AB (Sweden)

    2008-10-15

    The use of fossil but in first hand biobased alternative fuels in transportation has increased over the last decades. This change is primarily driven by concerns about climate change that is caused by emissions of fossil carbon dioxide and other greenhouse gases, but also by the impact on health and environment, caused by emissions of regulated as well as non-regulated emissions from the transport sector. Most alternative fuels will help to reduce the emissions of regulated and non-regulated emissions, while alternative fuels based on biomass also will contribute to reduced net emissions of carbon dioxide. Since the mid 1990s, the use of biomass based fuels such as ethanol and biodiesel has reached levels high enough in for example Europe, Brazil and the U.S. to motivate national or regional specifications/standards. Especially from the vehicle/engine manufacturer's point of view standards are of high importance. From early 2000 onwards, the international trade of biofuels (for example from Brazil to the U.S. and Europe) has grown, and this has created a need for common international specifications/standards. This report presents information about national and regional standards for alternative fuels, but also, when existing and reported, standards on a global level are described and discussed. Ongoing work concerning new or revised standards on alternative fuels on national, regional or global level is also discussed. In this report we have covered standards on all kind of alternative fuels, exemplified below. However, the focus is on liquid biofuels for diesel engines and Otto engines. 1) Liquid fuels for diesel engines (compression ignition engines), such as Fatty Acid Methyl Esters (FAME), Fatty Acid Ethyl Esters (FAEE), alcohols, alcohol derivates and synthetic diesel fuels. 2) Liquid fuels for Otto engines (spark ignition engines), such as alcohols, ethers and synthetic gasoline. 3) Liquefied fossil petroleum gas (LPG). 4) Di-Methyl Ether (DME). 5

  5. Review of nuclear fuel cycle alternatives including certain features pertaining to weapon proliferation

    International Nuclear Information System (INIS)

    Largely as a result of concerns over nuclear weapon proliferation, the U.S. program to develop and commercialize the plutonium-fueled breeder reactor has been slowed down; interest in alternative fuel cycles has increased. The report offers an informal review of the various nuclear fuel cycle options including some aspects relevant to weapon proliferation, although no complete review of the latter subject is attempted. Basic principles governing breeding, reactor safety, and efficient utilization of fission energy resources (thorium and uranium) are discussed. The controversial problems of weapon proliferation and its relation to fuel reprocessing (which is essential for efficient fuel cycles) are reviewed and a number of proposed approaches to reducing proliferation risks are noted. Some representative specific reactor concepts are described, with emphasis on their development status, their potentials for resource utilization, and their implications for proliferation

  6. An organization of the thorium fuel cycle start on the basis of fast reactors with spherical fuel elements of the small size

    International Nuclear Information System (INIS)

    The possibility of the organization of thorium fuel cycle start by means of conversion of high background plutonium into isotopically pure Uranium 233 into the highly stressed breeders with the fuel in the form of spherical fuel elements has been studied. A high efficiency of usage of compact plutonium fuel in the form of spherical fuel elements for its transmutation into low background Uranium 233 has been shown as a result of the revealed temporary regularities in the main characteristic behaviour of the reactors of such a type. (authors). 7 refs., 2 figs., 1 tab

  7. Alternatives to traditional transportation fuels 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-01

    This report provides information on transportation fuels other than gasoline and diesel, and the vehicles that use these fuels. The Energy Information Administration (EIA) provides this information to support the U.S. Department of Energy`s reporting obligations under Section 503 of the Energy Policy Act of 1992 (EPACT). The principal information contained in this report includes historical and year-ahead estimates of the following: (1) the number and type of alterative-fueled vehicles (AFV`s) in use; (2) the consumption of alternative transportation fuels and {open_quotes}replacement fuels{close_quotes}; and (3) the number and type of alterative-fueled vehicles made available in the current and following years. In addition, the report contains some material on special topics. The appendices include a discussion of the methodology used to develop the estimates (Appendix A), a map defining geographic regions used, and a list of AFV suppliers.

  8. Burn-up calculation of different thorium-based fuel matrixes in a thermal research reactor using MCNPX 2.6 code

    OpenAIRE

    Gholamzadeh Zohreh; Hossein Feghhi Seyed Amir; Soltani Leila; Rezazadeh Marzieh; Tenreiro Claudio; Joharifard Mahdi

    2014-01-01

    Decrease of the economically accessible uranium resources and the inherent proliferation resistance of thorium fuel motivate its application in nuclear power systems. Estimation of the nuclear reactor’s neutronic parameters during different operational situations is of key importance for the safe operation of nuclear reactors. In the present research, thorium oxide fuel burn-up calculations for a demonstrative model of a heavy water- -cooled reactor have been performed using MCNPX 2.6 code. N...

  9. Parametric study of thorium fuel cycles in a 100MWth pebble bed high temperature reactor / F. Panday

    OpenAIRE

    Panday, Farisha

    2011-01-01

    The current project was conducted in order to select an optimized open Thorium/Uranium fuel cycle for the Pebble Bed Modular Reactor (PBMR) concept in motivation for the 100MWth PBMR Power Plant. A sensitivity study on the heavy metal loading of the fuel sphere was performed to accomplish this task. The effect on various parameters was evaluated to determine the influence of varying the Heavy Metal (HM) from 6 gHM/sphere to 20 gHM/sphere and at different feed fuel enrichment...

  10. Alternative fuels: how real? how soon?

    International Nuclear Information System (INIS)

    Nations of the Organization for Economic Cooperation and Development (OECD) are looking for politically stable sources of oil in response to the ever growing demand for fuel. World oil consumption has reached 76.5 MMB/d and demand is expected to be 80 MMB/d by 2005. More restrictive environmental policies are resulting in improved conversion efficiency of oil dependent supply chains and the switching to alternative fuels. The adoption of new fuels however, depends on many factors such as the economic advantage, technological superiority, and convenience. The dominant electrical supply chains at the moment are nuclear, coal, hydropower, hydrocarbons, and renewable energy alternatives such as wind, solar and hydrogen fuels. The paper presented graphs illustrating adoption patterns for various fuels over the past century and presented a potential adoption pattern for fuel cell vehicles. Also included in this presentation were graphs depicting how price can drive supply chain demand and allow other fuels to gain market share. The impact of fuel substitution, efficiency and price effects was mentioned along with the impact of recent policy changes on vehicle fuel efficiency and carbon dioxide emissions. The role of government incentives to promote alternative fuel sales was also discussed along with a broad assessment of renewable supply chains. It was noted that most new fuels are linked to hydrocarbons. For example, hydrogen generation through water electrolysis requires petroleum generated electricity or the steam reforming of natural gas. Ethanol processes also require hydrocarbon consumption indirectly. It was noted that the average efficiencies of coal and natural gas plants has increased in the past decade and the incumbent price trends in electricity in the United States have decreased for fuels such as oil, gas, coal and nuclear energy. With ongoing innovation in the internal combustion engine in the past 30 years, the incumbents have also improved with

  11. Fossil Fuels, Alternative Energy and Economic Growth

    OpenAIRE

    Raul Barreto

    2013-01-01

    We present a theoretical framework that incorporates energy within an endogenous growth model. The model explicitly allows for the interaction and substitution between fossil fuels, defined as a non-renewable resource derived from some fixed initial stock, and alternative energy, defined as renewable resource whose production requires capital input. The dynamics of the model depict a unique balance growth to a saddle point. The consumption path temporarily peaks, when fossil fuels are plentif...

  12. Review of alternative fuels data bases

    Science.gov (United States)

    Harsha, P. T.; Edelman, R. B.

    1983-01-01

    Based on an analysis of the interaction of fuel physical and chemical properties with combustion characteristics and indicators, a ranking of the importance of various fuel properties with respect to the combustion process was established. This ranking was used to define a suite of specific experiments whose objective is the development of an alternative fuels design data base. Combustion characteristics and indicators examined include droplet and spray formation, droplet vaporization and burning, ignition and flame stabilization, flame temperature, laminar flame speed, combustion completion, soot emissions, NOx and SOx emissions, and the fuels' thermal and oxidative stability and fouling and corrosion characteristics. Key fuel property data is found to include composition, thermochemical data, chemical kinetic rate information, and certain physical properties.

  13. Design of a boiling water reactor equilibrium core using thorium-uranium fuel

    Energy Technology Data Exchange (ETDEWEB)

    Francois, J-L.; Nunez-Carrera, A.; Espinosa-Paredes, G.; Martin-del-Campo, C.

    2004-10-06

    In this paper the design of a Boiling Water Reactor (BWR) equilibrium core using thorium is presented; a heterogeneous blanket-seed core arrangement concept was adopted. The design was developed in three steps: in the first step two different assemblies were designed based on the integrated blanket-seed concept, they are the blanket-dummy assembly and the blanket-seed assembly. The integrated blanketseed concept comes from the fact that the blanket and the seed rods are located in the same assembly, and are burned-out in a once-through cycle. In the second step, a core design was developed to achieve an equilibrium cycle of 365 effective full power days in a standard BWR with a reload of 104 fuel assemblies designed with an average 235U enrichment of 7.5 w/o in the seed sub-lattice. The main operating parameters, like power, linear heat generation rate and void distributions were obtained as well as the shutdown margin. It was observed that the analyzed parameters behave like those obtained in a standard BWR. The shutdown margin design criterion was fulfilled by addition of a burnable poison region in the assembly. In the third step an in-house code was developed to evaluate the thorium equilibrium core under transient conditions. A stability analysis was also performed. Regarding the stability analysis, five operational states were analyzed; four of them define the traditional instability region corner of the power-flow map and the fifth one is the operational state for the full power condition. The frequency and the boiling length were calculated for each operational state. The frequency of the analyzed operational states was similar to that reported for BWRs; these are close to the unstable region that occurs due to the density wave oscillation phenomena in some nuclear power plants. Four transient analyses were also performed: manual SCRAM, recirculation pumps trip, main steam isolation valves closure and loss of feed water. The results of these transients are

  14. Design of a boiling water reactor equilibrium core using thorium-uranium fuel

    International Nuclear Information System (INIS)

    In this paper the design of a Boiling Water Reactor (BWR) equilibrium core using thorium is presented; a heterogeneous blanket-seed core arrangement concept was adopted. The design was developed in three steps: in the first step two different assemblies were designed based on the integrated blanket-seed concept, they are the blanket-dummy assembly and the blanket-seed assembly. The integrated blanketseed concept comes from the fact that the blanket and the seed rods are located in the same assembly, and are burned-out in a once-through cycle. In the second step, a core design was developed to achieve an equilibrium cycle of 365 effective full power days in a standard BWR with a reload of 104 fuel assemblies designed with an average 235U enrichment of 7.5 w/o in the seed sub-lattice. The main operating parameters, like power, linear heat generation rate and void distributions were obtained as well as the shutdown margin. It was observed that the analyzed parameters behave like those obtained in a standard BWR. The shutdown margin design criterion was fulfilled by addition of a burnable poison region in the assembly. In the third step an in-house code was developed to evaluate the thorium equilibrium core under transient conditions. A stability analysis was also performed. Regarding the stability analysis, five operational states were analyzed; four of them define the traditional instability region corner of the power-flow map and the fifth one is the operational state for the full power condition. The frequency and the boiling length were calculated for each operational state. The frequency of the analyzed operational states was similar to that reported for BWRs; these are close to the unstable region that occurs due to the density wave oscillation phenomena in some nuclear power plants. Four transient analyses were also performed: manual SCRAM, recirculation pumps trip, main steam isolation valves closure and loss of feed water. The results of these transients are

  15. Proliferation resistance and energy security advantages of a thorium-uranium dioxide once-through fuel cycle for light water reactors

    International Nuclear Information System (INIS)

    This study analyzes whether spent light reactor (LWR) thorium-uranium dioxide fuel poses a significantly lower risk for nuclear weapon proliferation than spent uranium-dioxide fuel, based on the isotopic composition of the contained uranium and plutonium. Mixed Th/U fuel with an initial enrichment of 19.5% U235 can achieve an average burnup of 70,000 MWd/tHM in a PWR using 30% UO2 and 70% ThO2. To get the equivalent burnup, LEU fuel requires an initial enrichment of 8.0% U235. Two computer codes, MCNP and ORIGEN2, are used to perform the depletion calculation. The spent mixed thorium-uranium dioxide fuel discharged from a pressurized-water reactor has a plutonium isotopic composition and higher decay heat production per kilogram of plutonium more proliferation resistant than spent low enriched uranium dioxide fuel, while significantly reducing the quantity of plutonium produced. The U233 + U235 mixture in spent thorium-uranium fuel is low enriched and contaminated with gamma-emitting U232. With respect to energy security, the introduction of a thorium-uranium fuel cycle could reduce concern over uranium fuel supply of a resource-poor nation since thorium reserve is much larger, compared to fuel cycles using 4.5% LEU, while its uranium saving is almost equivalent to plutonium recycling. Overall, spent thorium-uranium fuel appears significantly more proliferation resistant in terms of the weapons-usability of the contained fissile material than spent low enriched uranium fuel, although use of 19.5% enriched uranium in fresh fuel would facilitate production of weapons-grade uranium at a higher rate in countries with clandestine enrichment facilities. (S.Y.)

  16. A Pressurized Water Reactor Plutonium Incinerator Based on Thorium Fuel and Seed-Blanket Assembly Geometry

    International Nuclear Information System (INIS)

    A pressurized water reactor (PWR) fuel cycle is proposed, whose purpose is the elimination and degradation of weapons-grade plutonium. This Radkowsky thorium-fuel Pu incinerator (RTPI) cycle is based on a core and assemblies retrofittable to a Westinghouse-type PWR. The RTPI assembly, however, is a seed-blanket unit. The seed is supercritical, loaded with Pu-Zr alloy as fuel in a high moderator-to-fuel ratio configuration. The blanket is subcritical, loaded mainly with ThO2, generating and burning 233U in situ. Blankets are loaded once every 6 yr. The seed fuel management scheme is based on three batches, with one-third of the seed modules replaced every year. The core generates 1100 MW(electric). Equilibrium conditions are achieved with the second seed loading. For equilibrium conditions, the annual average of disposed (loaded) Pu is 1210 kg, of which 702 kg are completely eliminated, and 508 kg are discharged, but with significantly degraded isotopics (i.e., with a high percentage of even mass isotopes). Spontaneous fissions per second in a gram of this degraded Pu are ∼500, resulting in significantly increased proliferation resistance.Every 6 yr the blanket discharge contains 780 kg of 233U (including 233Pa) and 36 kg of 235U. However, the blankets are initially loaded with an amount of natural uranium selected such that these U fissile isotopes constitute only 12% of the total U discharge, a percentage equivalent to 20% 235U enrichment; hence, both the discharged uranium isotopics satisfy proliferation-resistant criteria.The RTPI control variables, namely, the moderator temperature coefficient, the reactivity per ppm boron, and the control rods worth, are about equal to those of a PWR. The RTPI spent-fuel stockpile ingestion toxicity over a period of ten million years is about the same as the counterpart toxicities of a regular, or a mixed-oxide (MOX), PWR. Compared with known PWR MOX variants, the RTPI is, per 1000 MW(electric) and per annum, a significantly

  17. Alternative transportation fuels and air quality

    International Nuclear Information System (INIS)

    The paper discusses the air quality impact of the following alternative fuels: reformulated gasoline, methanol, ethanol, diesel, compressed natural gas, liquid petroleum gases, hydrogen, and electric power. Emissions of NOx, CO, and toxic compounds, as well as global climatic change impacts are described

  18. Spent Nuclear Fuel Alternative Technology Decision Analysis

    International Nuclear Information System (INIS)

    The Westinghouse Savannah River Company (WSRC) made a FY98 commitment to the Department of Energy (DOE) to recommend a technology for the disposal of aluminum-based spent nuclear fuel (SNF) at the Savannah River Site (SRS). The two technologies being considered, direct co-disposal and melt and dilute, had been previously selected from a group of eleven potential SNF management technologies by the Research Reactor Spent Nuclear Fuel Task Team chartered by the DOE''s Office of Spent Fuel Management. To meet this commitment, WSRC organized the SNF Alternative Technology Program to further develop the direct co-disposal and melt and dilute technologies and ultimately provide a WSRC recommendation to DOE on a preferred SNF alternative management technology

  19. Spent Nuclear Fuel Alternative Technology Decision Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Shedrow, C.B.

    1999-11-29

    The Westinghouse Savannah River Company (WSRC) made a FY98 commitment to the Department of Energy (DOE) to recommend a technology for the disposal of aluminum-based spent nuclear fuel (SNF) at the Savannah River Site (SRS). The two technologies being considered, direct co-disposal and melt and dilute, had been previously selected from a group of eleven potential SNF management technologies by the Research Reactor Spent Nuclear Fuel Task Team chartered by the DOE''s Office of Spent Fuel Management. To meet this commitment, WSRC organized the SNF Alternative Technology Program to further develop the direct co-disposal and melt and dilute technologies and ultimately provide a WSRC recommendation to DOE on a preferred SNF alternative management technology.

  20. Production of jet fuel from alternative source

    Energy Technology Data Exchange (ETDEWEB)

    Eller, Zoltan; Papp, Anita; Hancsok, Jenoe [Pannonia Univ., Veszprem (Hungary). MOL Dept. of Hydrocarbon and Coal Processing

    2013-06-01

    Recent demands for low aromatic content jet fuels have shown significant increase in the last 20 years. This was generated by the growing of aviation. Furthermore, the quality requirements have become more aggravated for jet fuels. Nowadays reduced aromatic hydrocarbon fractions are necessary for the production of jet fuels with good burning properties, which contribute to less harmful material emission. In the recent past the properties of gasolines and diesel gas oils were continuously severed, and the properties of jet fuels will be more severe, too. Furthermore, it can become obligatory to blend alternative components into jet fuels. With the aromatic content reduction there is a possibility to produce high energy content jet fuels with the desirable properties. One of the possibilities is the blending of biocomponents from catalytic hydrogenation of triglycerides. Our aim was to study the possibilities of producing low sulphur and aromatic content jet fuels in a catalytic way. On a CoMo/Al{sub 2}O{sub 3} catalyst we studied the possibilities of quality improving of a kerosene fraction and coconut oil mixture depending on the change of the process parameters (temperature, pressure, liquid hourly space velocity, volume ratio). Based on the quality parameters of the liquid products we found that we made from the feedstock in the adequate technological conditions products which have a high smoke point (> 35 mm) and which have reduced aromatic content and high paraffin content (90%), so these are excellent jet fuels, and their stack gases damage the environment less. (orig.)

  1. Preliminary design study of small long life boiling water reactor (BWR) with tight lattice thorium nitride fuel

    Science.gov (United States)

    Trianti, Nuri; Su'ud, Zaki; Arif, Idam; Riyana, EkaSapta

    2014-09-01

    Neutronic performance of small long-life boiling water reactors (BWR) with thorium nitride based fuel has been performed. A recent study conducted on BWR in tight lattice environments (with a lower moderator percentage) produces small power reactor which has some specifications, i.e. 10 years operation time, power density of 19.1 watt/cc and maximum excess reactivity of about 4%. This excess reactivity value is smaller than standard reactivity of conventional BWR. The use of hexagonal geometry on the fuel cell of BWR provides a substantial effect on the criticality of the reactor to obtain a longer operating time. Supported by a tight concept lattice where the volume fraction of the fuel is greater than the moderator and fuel, Thorium Nitride give good results for fuel cell design on small long life BWR. The excess reactivity of the reactor can be reduced with the addition of gadolinium as burnable poisons. Therefore the hexagonal tight lattice fuel cell design of small long life BWR that has a criticality more than 20 years of operating time has been obtained.

  2. Preliminary design study of small long life boiling water reactor (BWR) with tight lattice thorium nitride fuel

    International Nuclear Information System (INIS)

    Neutronic performance of small long-life boiling water reactors (BWR) with thorium nitride based fuel has been performed. A recent study conducted on BWR in tight lattice environments (with a lower moderator percentage) produces small power reactor which has some specifications, i.e. 10 years operation time, power density of 19.1 watt/cc and maximum excess reactivity of about 4%. This excess reactivity value is smaller than standard reactivity of conventional BWR. The use of hexagonal geometry on the fuel cell of BWR provides a substantial effect on the criticality of the reactor to obtain a longer operating time. Supported by a tight concept lattice where the volume fraction of the fuel is greater than the moderator and fuel, Thorium Nitride give good results for fuel cell design on small long life BWR. The excess reactivity of the reactor can be reduced with the addition of gadolinium as burnable poisons. Therefore the hexagonal tight lattice fuel cell design of small long life BWR that has a criticality more than 20 years of operating time has been obtained

  3. Design of an equilibrium nucleus of a BWR type reactor based in a Thorium-Uranium fuel

    International Nuclear Information System (INIS)

    In this work the design of the reactor nucleus of boiling water using fuel of thorium-uranium is presented. Starting from an integral concept based in a type cover-seed assemble is carried out the design of an equilibrium reload for the nucleus of a reactor like that of the Laguna Verde Central and its are analyzed some of the main design variables like the cycle length, the reload fraction, the burnt fuel, the vacuum distribution, the generation of lineal heat, the margin of shutdown, as well as a first estimation of the fuel cost. The results show that it is feasible to obtain an equilibrium reload, comparable to those that are carried out in the Laguna Verde reactors, with a good behavior of those analyzed variables. The cost of the equilibrium reload designed with the thorium-uranium fuel is approximately 2% high that the uranium reload producing the same energy. It is concluded that it is convenient to include burnable poisons, type gadolinium, in the fuel with the end of improving the reload design, the fuel costs and the margin of shutdown. (Author)

  4. Alternative Fuel for Portland Cement Processing

    Energy Technology Data Exchange (ETDEWEB)

    Schindler, Anton K; Duke, Steve R; Burch, Thomas E; Davis, Edward W; Zee, Ralph H; Bransby, David I; Hopkins, Carla; Thompson, Rutherford L; Duan, Jingran; ; Venkatasubramanian, Vignesh; Stephen, Giles

    2012-06-30

    The production of cement involves a combination of numerous raw materials, strictly monitored system processes, and temperatures on the order of 1500 °C. Immense quantities of fuel are required for the production of cement. Traditionally, energy from fossil fuels was solely relied upon for the production of cement. The overarching project objective is to evaluate the use of alternative fuels to lessen the dependence on non-renewable resources to produce portland cement. The key objective of using alternative fuels is to continue to produce high-quality cement while decreasing the use of non-renewable fuels and minimizing the impact on the environment. Burn characteristics and thermodynamic parameters were evaluated with a laboratory burn simulator under conditions that mimic those in the preheater where the fuels are brought into a cement plant. A drop-tube furnace and visualization method were developed that show potential for evaluating time- and space-resolved temperature distributions for fuel solid particles and liquid droplets undergoing combustion in various combustion atmospheres. Downdraft gasification has been explored as a means to extract chemical energy from poultry litter while limiting the throughput of potentially deleterious components with regards to use in firing a cement kiln. Results have shown that the clinkering is temperature independent, at least within the controllable temperature range. Limestone also had only a slight effect on the fusion when used to coat the pellets. However, limestone addition did display some promise in regards to chlorine capture, as ash analyses showed chlorine concentrations of more than four times greater in the limestone infused ash as compared to raw poultry litter. A reliable and convenient sampling procedure was developed to estimate the combustion quality of broiler litter that is the best compromise between convenience and reliability by means of statistical analysis. Multi-day trial burns were conducted

  5. Model for the analysis of transitories and stability of a BWR reactor with fuel of thorium

    International Nuclear Information System (INIS)

    In this work it is described the thermo hydraulic and neutronic pattern used to simulate the behavior of a nucleus of thorium-uranium under different conditions of operation. The analysed nucleus was designed with base to assemblies that operate under the cover-seed concept. The pattern was proven to conditions of stationary state and transitory state. Here it is only presented the simulation of the one SCRAM manual and it is compared in the behavior of a nucleus with UO2. Additionally one carries out an analysis of stability taking into account the four corners that define the area of stability of the map flow-power and to conditions of 100% of flow and 100% of power. The module of stability is based on the pattern of Lahey and Podowsky to estimate the drops of pressure during a perturbation. It is concludes that the behavior of this nucleus is not very different to the one shown by the nuclei loaded with the fuel of UO2. (Author)

  6. Fuel cycle modelling of open cycle thorium-fuelled nuclear energy systems

    International Nuclear Information System (INIS)

    in incorporating thorium into nuclear energy systems operating with open nuclear fuel cycles

  7. Use of alternative fuels in solid oxide fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-05-15

    A future sustainable energy system will certainly be based on a variety of environmentally benign energy production technologies. Fuel cells can be a key element in this scenario. One of the fuel cells types the solid oxide fuel cell (SOFC) has a number of advantages that places them in a favorable position: high efficiency, parallel production of electricity and high value heat, prevention of NOx emission, flexibility regarding usable fuels, and certain tolerance towards impurities. It is thus a natural option, to combine such a highly efficient energy conversion tool with a sustainable fuel supply. In the present contribution, the use of alternative compared to conventional fuels in SOFCs was evaluated. Regarding carbon containing, biomass derived fuels, SOFCs showed excellent power output and stability behavior during long-term testing under technologically relevant conditions. Moreover, ammonia can be used directly as fuel. The chemical and structural properties of the SOFC anode makes it even possible, to combine a chemical conversion of the fuel, for example methane into synthesis gas via steam reforming and decomposition of ammonia into hydrogen and nitrogen, with the electrochemical production of electricity in one step. (au)

  8. The Tasse concept (thorium based accelerator driven system with simplified fuel cycle for long term energy production)

    Energy Technology Data Exchange (ETDEWEB)

    Berthou, V. [CEA Cadarache, 13 - Saint Paul lez Durance (France); Slessarev, I.; Salvatores, M. [IRI, TU Delft (Netherlands)

    2001-07-01

    Within the framework of the nuclear waste management studies, the ''one-component''. concept has to be considered as an attractive option in the long-term perspective. This paper proposes a new system called TASSE (''Thorium based Accelerator driven System with Simplified fuel cycle for long term Energy production''.), destined to the current French park renewal. The main idea of the TASSE concept is to simplify both the front and the back end of the fuel cycle, and his major goals are to provide electricity with low waste production, and with an economical competitiveness. (author)

  9. The Tasse concept (thorium based accelerator driven system with simplified fuel cycle for long term energy production)

    International Nuclear Information System (INIS)

    Within the framework of the nuclear waste management studies, the ''one-component''. concept has to be considered as an attractive option in the long-term perspective. This paper proposes a new system called TASSE (''Thorium based Accelerator driven System with Simplified fuel cycle for long term Energy production''.), destined to the current French park renewal. The main idea of the TASSE concept is to simplify both the front and the back end of the fuel cycle, and his major goals are to provide electricity with low waste production, and with an economical competitiveness. (author)

  10. Hydrogen as alternative clean fuel: Economic analysis

    International Nuclear Information System (INIS)

    In analogy to biofuel production from biomasses, the electrolytic conversion of other renewable energies into hydrogen as an alternative clean fuel is considered. This solution allows the intermittent renewable energy sources, as photovoltaics and wind energy, to enhance their development and enlarge the role into conventional fuel market. A rough economic analysis of hydrogen production line shows the costs, added by electrolysis and storage stages, can be recovered by properly accounting for social and environmental costs due to whole cycle of conventional fuels, from production to use. So, in a perspective of attaining the economic competitiveness of renewable energy, the hydrogen, arising from intermittent renewable energy sources, will be able to compete in the energy market with conventional fuels, making sure that their substitution will occur in a significant amount and the corresponding environment

  11. Thorium utilization in power reactors

    International Nuclear Information System (INIS)

    In this work the recent (prior to Aug, 1976) literature on thorium utilization is reviewed briefly and the available information is updated. After reviewing the nuclear properties relevant to the thorium fuel cycle we describe briefly the reactor systems that have been proposed using thorium as a fertile material. (author)

  12. Systems impacts of spent fuel disassembly alternatives

    International Nuclear Information System (INIS)

    Three studies were completed to evaluate four alternatives to the disposal of intact spent fuel assemblies in a geologic repository. A preferred spent fuel waste form for disposal was recommended on consideration of (1) package design and fuel/package interaction, (2) long-term, in-repository performance of the waste form, and (3) overall process performance and costs for packaging, handling, and emplacement. The four basic alternative waste forms considered were (1) end fitting removal, (2) fission gas venting, (3) disassembly and close packing, and (4) shearing/immobilization. None of the findings ruled out any alternative on the basis of waste package considerations or long-term performance of the waste form. The third alternative offers flexibility in loading that may prove attractive in the various geologic media under consideration, greatly reduces the number of packages, and has the lowest unit cost. These studies were completed in October, 1981. Since then Westinghouse Electric Corporation and the Office of Nuclear Waste Isolation have completed studies in related fields. This report is now being published to provide publicly the background material that is contained within. 47 references, 28 figures, 31 tables

  13. Systems impacts of spent fuel disassembly alternatives

    Energy Technology Data Exchange (ETDEWEB)

    1984-07-01

    Three studies were completed to evaluate four alternatives to the disposal of intact spent fuel assemblies in a geologic repository. A preferred spent fuel waste form for disposal was recommended on consideration of (1) package design and fuel/package interaction, (2) long-term, in-repository performance of the waste form, and (3) overall process performance and costs for packaging, handling, and emplacement. The four basic alternative waste forms considered were (1) end fitting removal, (2) fission gas venting, (3) disassembly and close packing, and (4) shearing/immobilization. None of the findings ruled out any alternative on the basis of waste package considerations or long-term performance of the waste form. The third alternative offers flexibility in loading that may prove attractive in the various geologic media under consideration, greatly reduces the number of packages, and has the lowest unit cost. These studies were completed in October, 1981. Since then Westinghouse Electric Corporation and the Office of Nuclear Waste Isolation have completed studies in related fields. This report is now being published to provide publicly the background material that is contained within. 47 references, 28 figures, 31 tables.

  14. The Potential Role of the Thorium Fuel Cycle in Reducing the Radiotoxicity of Long-Lived Waste - 13477

    International Nuclear Information System (INIS)

    The thorium (or more accurately the Th-232/U-233) fuel cycle is attracting growing interest world wide and one reason for this is the reduced radiotoxicity of long-lived waste, with the Th- 232/U-233 fuel cycle often being justified partly on the grounds of low radiotoxicity for long cooling times. This paper considers the evolution of heavy metal radiotoxicity in a Molten Salt Fast Reactor (MSFR) operating a closed Th-232/U-233 cycle during different operational phases. The paper shows that even in the MSFR core, the equilibrium radiotoxicity of the thorium fuel cycle is only reached after almost 100 years of operation. MSFR was chosen because it has many theoretical advantages that favour the Th-232/U-233 fuel cycle. Conventional solid fuel systems would be expected to behave similarly, but with even longer timescales and therefore the MSFR cycle can be used to define the limits of what is practically achievable. The results are used to argue the case that a fair approach to justifying the Th-232/U-233 breeder cycle should not quote the long term equilibrium radiotoxicity, but rather the somewhat less favourable radiotoxicity that could be achieved within the operational lifetime of the first generation of Th-232/U-233 breeder reactors. (authors)

  15. Solid Oxide Fuel Cells Operating on Alternative and Renewable Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiaoxing; Quan, Wenying; Xiao, Jing; Peduzzi, Emanuela; Fujii, Mamoru; Sun, Funxia; Shalaby, Cigdem; Li, Yan; Xie, Chao; Ma, Xiaoliang; Johnson, David; Lee, Jeong; Fedkin, Mark; LaBarbera, Mark; Das, Debanjan; Thompson, David; Lvov, Serguei; Song, Chunshan

    2014-09-30

    This DOE project at the Pennsylvania State University (Penn State) initially involved Siemens Energy, Inc. to (1) develop new fuel processing approaches for using selected alternative and renewable fuels – anaerobic digester gas (ADG) and commercial diesel fuel (with 15 ppm sulfur) – in solid oxide fuel cell (SOFC) power generation systems; and (2) conduct integrated fuel processor – SOFC system tests to evaluate the performance of the fuel processors and overall systems. Siemens Energy Inc. was to provide SOFC system to Penn State for testing. The Siemens work was carried out at Siemens Energy Inc. in Pittsburgh, PA. The unexpected restructuring in Siemens organization, however, led to the elimination of the Siemens Stationary Fuel Cell Division within the company. Unfortunately, this led to the Siemens subcontract with Penn State ending on September 23rd, 2010. SOFC system was never delivered to Penn State. With the assistance of NETL project manager, the Penn State team has since developed a collaborative research with Delphi as the new subcontractor and this work involved the testing of a stack of planar solid oxide fuel cells from Delphi.

  16. LWR Thorium-Based Equilibrium-TRU (TRU-sustainable) Fuel Cycle: From 2D Fuel Lattice Model to the Full 3D Core Level Model

    International Nuclear Information System (INIS)

    A study was performed in the BNL to investigate LWR thorium-based equilibrium-TRU (TRU-sustainable) fuel cycle. In such a self-sustainable fuel cycle, only TRU lost by the fuel separation activities passes to the repository. The equilibrium transuranics inventory is recycled into each subsequent reload. Results of the study demonstrate the neutronic feasibility of a fuel cycle with ''zero-TRU'' discharge. A limitation of this study is the fact that a 2D fuel lattice model was used, specifically, the linear reactivity model, applied to the results of assembly calculations, assumes a single fuel type for all three batches. Thus, the end result of this work is a confirmation of the possibility of establishing equilibrium TRU fuel cycle via the full 3D core level calculational model

  17. Thermal-mechanical performance modeling of thorium-plutonium oxide fuel and comparison with on-line irradiation data

    Science.gov (United States)

    Insulander Björk, Klara; Kekkonen, Laura

    2015-12-01

    Thorium-plutonium Mixed OXide (Th-MOX) fuel is considered for use in light water reactors fuel due to some inherent benefits over conventional fuel types in terms of neutronic properties. The good material properties of ThO2 also suggest benefits in terms of thermal-mechanical fuel performance, but the use of Th-MOX fuel for commercial power production demands that its thermal-mechanical behavior can be accurately predicted using a well validated fuel performance code. Given the scant operational experience with Th-MOX fuel, no such code is available today. This article describes the first phase of the development of such a code, based on the well-established code FRAPCON 3.4, and in particular the correlations reviewed and chosen for the fuel material properties. The results of fuel temperature calculations with the code in its current state of development are shown and compared with data from a Th-MOX test irradiation campaign which is underway in the Halden research reactor. The results are good for fresh fuel, whereas experimental complications make it difficult to judge the adequacy of the code for simulations of irradiated fuel.

  18. 76 FR 67287 - Alternative Fuel Transportation Program; Alternative Fueled Vehicle Credit Program (Subpart F...

    Science.gov (United States)

    2011-10-31

    ... and Plug-In Hybrid Electric Vehicles C. Investments 1. Alternative Fuel Infrastructure 2. Alternative... plug-in hybrid electric vehicles (PHEV) are commercialized (see Part IV.B.2 below). Except in those... EPAct 1992, as amended, as ``an electric, hybrid electric, or plug-in hybrid electric vehicle with...

  19. Alternate fuel cycles for fast breeder reactors

    International Nuclear Information System (INIS)

    In this contribution to the syllabus for Subgroup 5D, a full range of alternate breeder fuel cycle options is developed and explored as to energy supply capability, resource utilizations, performance characteristics and technical features that pertain to proliferation resistance. Breeding performance information is presented for designs based on Pu/U, Pu/Th, 233 U/U, etc. with oxide, carbide or metal fuel; with lesser emphasis, heterogeneous and homogeneous concepts are presented. A potential proliferation resistance advantage of a symbiotic system of a Pu/U core, Th blanket breeder producing 233 U for utilization in dispersed LWR's is identified. LWR support ratios for various reactor and fuel types and the increase in uranium consumption with higher support ratios are identified

  20. Adapting the deep burn in-core fuel management strategy for the gas turbine - modular helium reactor to a uranium-thorium fuel

    Energy Technology Data Exchange (ETDEWEB)

    Talamo, Alberto [Department of Nuclear and Reactor Physics, Royal Institute of Technology, Roslagstullsbacken 21, S-10691, Stockholm (Sweden)]. E-mail: alby@neutron.kth.se; Gudowski, Waclaw [Department of Nuclear and Reactor Physics, Royal Institute of Technology, Roslagstullsbacken 21, S-10691, Stockholm (Sweden)

    2005-11-15

    In 1966, Philadelphia Electric has put into operation the Peach Bottom I nuclear reactor, it was the first high temperature gas reactor (HTGR); the pioneering of the helium-cooled and graphite-moderated power reactors continued with the Fort St. Vrain and THTR reactors, which operated until 1989. The experience on HTGRs lead General Atomics to design the gas turbine - modular helium reactor (GT-MHR), which adapts the previous HTGRs to the generation IV of nuclear reactors. One of the major benefits of the GT-MHR is the ability to work on the most different types of fuels: light water reactors waste, military plutonium, MOX and thorium. In this work, we focused on the last type of fuel and we propose a mixture of 40% thorium and 60% uranium. In a uranium-thorium fuel, three fissile isotopes mainly sustain the criticality of the reactor: {sup 235}U, which represents the 20% of the fresh uranium, {sup 233}U, which is produced by the transmutation of fertile {sup 232}Th, and {sup 239}Pu, which is produced by the transmutation of fertile {sup 238}U. In order to compensate the depletion of {sup 235}U with the breeding of {sup 233}U and {sup 239}Pu, the quantity of fertile nuclides must be much larger than that one of {sup 235}U because of the small capture cross-section of the fertile nuclides, in the thermal neutron energy range, compared to that one of {sup 235}U. At the same time, the amount of {sup 235}U must be large enough to set the criticality condition of the reactor. The simultaneous satisfaction of the two above constrains induces the necessity to load the reactor with a huge mass of fuel; that is accomplished by equipping the fuel pins with the JAERI TRISO particles. We start the operation of the reactor with loading fresh fuel into all the three rings of the GT-MHR and after 810 days we initiate a refueling and shuffling schedule that, in 9 irradiation periods, approaches the equilibrium of the fuel composition. The analysis of the k {sub eff} and mass

  1. Adapting the deep burn in-core fuel management strategy for the gas turbine - modular helium reactor to a uranium-thorium fuel

    International Nuclear Information System (INIS)

    In 1966, Philadelphia Electric has put into operation the Peach Bottom I nuclear reactor, it was the first high temperature gas reactor (HTGR); the pioneering of the helium-cooled and graphite-moderated power reactors continued with the Fort St. Vrain and THTR reactors, which operated until 1989. The experience on HTGRs lead General Atomics to design the gas turbine - modular helium reactor (GT-MHR), which adapts the previous HTGRs to the generation IV of nuclear reactors. One of the major benefits of the GT-MHR is the ability to work on the most different types of fuels: light water reactors waste, military plutonium, MOX and thorium. In this work, we focused on the last type of fuel and we propose a mixture of 40% thorium and 60% uranium. In a uranium-thorium fuel, three fissile isotopes mainly sustain the criticality of the reactor: 235U, which represents the 20% of the fresh uranium, 233U, which is produced by the transmutation of fertile 232Th, and 239Pu, which is produced by the transmutation of fertile 238U. In order to compensate the depletion of 235U with the breeding of 233U and 239Pu, the quantity of fertile nuclides must be much larger than that one of 235U because of the small capture cross-section of the fertile nuclides, in the thermal neutron energy range, compared to that one of 235U. At the same time, the amount of 235U must be large enough to set the criticality condition of the reactor. The simultaneous satisfaction of the two above constrains induces the necessity to load the reactor with a huge mass of fuel; that is accomplished by equipping the fuel pins with the JAERI TRISO particles. We start the operation of the reactor with loading fresh fuel into all the three rings of the GT-MHR and after 810 days we initiate a refueling and shuffling schedule that, in 9 irradiation periods, approaches the equilibrium of the fuel composition. The analysis of the k eff and mass evolution, reaction rates, neutron flux and spectrum at the equilibrium of

  2. Effect of alternative fuel properties on NOx reduction

    OpenAIRE

    Axelsen, Ernst Petter; Tokheim, Lars-André; Bjerketvedt, Dag

    2002-01-01

    Today we see a substantial increase in the use of alternative fuels in the cement industry. The prospect of reduction in fuel costs and the environmental benefits of waste to energy conversion are the driving forces. For several years Norcem have steadily increased their use of alternative fuels such as refuse derived fuel (RDF), liquid hazardous waste (LHW), solid hazardous waste (SHW), animal meal (AM) and waste oil (WO). Alternative fuels behave differently compared to e.g. coa...

  3. Proceedings of the 1996 Windsor workshop on alternative fuels

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-10-01

    This document contains information which was presented at the 1996 Windsor Workshop on Alternative Fuels. Topics include: international links; industry topics and infrastructure issues; propane; engine developments; the cleanliness of alternative fuels; heavy duty alternative fuel engines; California zev commercialization efforts; and in-use experience.

  4. 18 CFR 281.304 - Computation of alternative fuel volume.

    Science.gov (United States)

    2010-04-01

    ... alternative fuel volume. 281.304 Section 281.304 Conservation of Power and Water Resources FEDERAL ENERGY... Determination § 281.304 Computation of alternative fuel volume. (a) General rule. For purposes of § 281.208(b)(1)(i)(B), and § 281.305: (1) Alternative fuel volume of an essential agricultural user is equal to...

  5. Potential advantages and drawbacks of the thorium fuel cycle in relation to current practice: A BNFL view

    International Nuclear Information System (INIS)

    Thorium could extend the availability of nuclear fuel beyond the necessarily finite reserves of uranium ore, particularly if used in a thermal breeder system with the uranium-233 formed by transmutation serving as fissile content. The cycle produces virtually no plutonium, nor the other transuranic elements that contribute substantially to anxieties about the disposal of nuclear waste. Thorium-based fuels have therefore been proposed as a substitute for uranium, both in existing power reactors and in advanced systems such as the 'energy amplified,' with a sub-critical assembly of fissile and fertile material driven by an independent neutron source. The benefits and drawbacks of thorium need careful evaluation. A self-sustaining, breeding cycle should be possible with good neutron economy, but whether existing modern reactor types meet that condition is questionable, particularly at high fuel ratings where parasitic absorption by 233Pa tends to pre-empt decay to 233U. Radiation from thallium-208, formed in the decay of by-product 232U and 228Th, complicates storage and refabrication. Public perception would favour the cycles producing no transuranic elements and its particular capacity for consuming those already stocked; however, although they contribute largely to the long-lived content of nuclear waste, fission products also do likewise, and since the amounts of these are not greatly changed, any resulting improvement to long-term safety would by no means be decisive. BNFL has recently assessed the outstanding development requirements of the Thorex process. Commercial realisation would require a huge investment with no certainty of success. So far, the potential advantages do not seem likely to justify the risk, but the position is being kept under review in case the balance should be seen to shift. (author)

  6. Light water reactor fuel element suitable for thorium employment in a discrete seed and blanket configuration with the aim to attain conversion ratios above the range of one

    International Nuclear Information System (INIS)

    The thorium resources in the world are relatively large. According to the IAEA-NEA-publication ''Red Book'' they amount to 4.5 10E6 metric tons and are about 4 times greater than the resources of Uranium. The fuel element described in this paper could be used in light water reactor (LWR) preferably in pressurized water reactor (PWR). The seed (feed) rods contain uranium 235 as fissionable material and the blanket (breed) rods contain thorium and uranium. The thorium in the blanket rods is converted to fissionable U-233 by irradiation with thermal neutrons. The U-233 produced is a valuable fissionable material and is characterized by high revalues, where t is defined as the number of fission neutrons per absorption in fissile materials. By optimized configuration and loading of the seed- and blanket rods the thorium is converted to U-233 and the U-238 is converted to fissionable Plutonium isotopes. Consequently more fissionable material is generated than is used. The fuel cycle is also flexible. Thus U-235, Pu-239 or weapons-grade Plutonium can be used.Based on knowledge obtained in the development of fuel elements for material test reactors (MTR), high temperature reactors (HTR) and light water reactors (LWR), a new design of fuel element suitable for thorium employment in PWR is described.

  7. Neutronic and Isotopic Simulation of a Thorium-TRU's fuel Closed Cycle in a Lead Cooled ADS

    International Nuclear Information System (INIS)

    The FACET group at CIEMAT is studying the properties and potentialities of several lead-cooled ADS designs for actinide and fission product transmutation. The main characteristics of these systems are the use of lead as primary coolant and moderator and fuels made by transuranics inside a thorium oxide matrix. The strategy assumed in this simulation implies that every discharge of the ADS will be reprocessed and would produce four waste streams: fission and activation products, remaining ''232 Th, produced ''233 U and remaining TRU's. The ''233 U is separated for other purposes; the remaining TRU are recovered altogether and mixed with the adequate amount of ''232 Th and fresh TRUs coming from LWR spent fuel. The simulations performed in this study have been focused primarily in the evolution of the fuel isotopic composition during and after each ADS burn-up cycle. (Author) 10 refs

  8. A Computational Analysis of Thorium Dioxide and Th(1-x)UxO2 Systems

    OpenAIRE

    A. E. Shields

    2015-01-01

    Nuclear power generation is an important way to satisfy rising global energy needs without increasing dependence on coal and petroleum. However, conventional nuclear fuels, such as uranium and plutonium dioxides, raise several safety concerns. Many countries have shown a renewed interest in thorium-based fuels as a potentially safer alternative. Thorium dioxide requires small amounts of a neutron source, such as uranium or plutonium, to generate a sustainable fission reaction. Due to the haza...

  9. TRISO Fuel Performance: Modeling, Integration into Mainstream Design Studies, and Application to a Thorium-fueled Fusion-Fission Hybrid Blanket

    Energy Technology Data Exchange (ETDEWEB)

    Powers, Jeffrey James [Univ. of California, Berkeley, CA (United States)

    2011-11-30

    This study focused on creating a new tristructural isotropic (TRISO) coated particle fuel performance model and demonstrating the integration of this model into an existing system of neutronics and heat transfer codes, creating a user-friendly option for including fuel performance analysis within system design optimization and system-level trade-off studies. The end product enables both a deeper understanding and better overall system performance of nuclear energy systems limited or greatly impacted by TRISO fuel performance. A thorium-fueled hybrid fusion-fission Laser Inertial Fusion Energy (LIFE) blanket design was used for illustrating the application of this new capability and demonstrated both the importance of integrating fuel performance calculations into mainstream design studies and the impact that this new integrated analysis had on system-level design decisions. A new TRISO fuel performance model named TRIUNE was developed and verified and validated during this work with a novel methodology established for simulating the actual lifetime of a TRISO particle during repeated passes through a pebble bed. In addition, integrated self-consistent calculations were performed for neutronics depletion analysis, heat transfer calculations, and then fuel performance modeling for a full parametric study that encompassed over 80 different design options that went through all three phases of analysis. Lastly, side studies were performed that included a comparison of thorium and depleted uranium (DU) LIFE blankets as well as some uncertainty quantification work to help guide future experimental work by assessing what material properties in TRISO fuel performance modeling are most in need of improvement. A recommended thorium-fueled hybrid LIFE engine design was identified with an initial fuel load of 20MT of thorium, 15% TRISO packing within the graphite fuel pebbles, and a 20cm neutron multiplier layer with beryllium pebbles in flibe molten salt coolant. It operated

  10. Overview of alternate-fuel fusion

    International Nuclear Information System (INIS)

    Alternate fuels (AFs) such as Cat-D, D-3He and p-11B offer the potential advantages of elimination of tritium breeding and reduced energy release in neutrons. An adequate energy balance appears exceedingly difficult to achieve with proton-based fuels such as p-11B. Thus Cat-D, which can ignite at temperatures in the range of 30 to 40 keV, represents the logical near-term candidate. An attractive variation which adds flexibility would be to develop semi-catalyzed-D plants for synfuel production with simultaneous generation of 3He for use in D-3He satellite electrical power plants. These approaches and problems are discussed

  11. Preliminary ecotoxicity assessment of new generation alternative fuels in seawater.

    Science.gov (United States)

    Rosen, Gunther; Dolecal, Renee E; Colvin, Marienne A; George, Robert D

    2014-06-01

    The United States Navy (USN) is currently demonstrating the viability of environmentally sustainable alternative fuels to power its fleet comprised of aircraft and ships. As with any fuel used in a maritime setting, there is potential for introduction into the environment through transport, storage, and spills. However, while alternative fuels are often presumed to be eco-friendly relative to conventional petroleum-based fuels, their environmental fate and effects on marine environments are essentially unknown. Here, standard laboratory-based toxicity experiments were conducted for two alternative fuels, jet fuel derived from Camelina sativa (wild flax) seeds (HRJ5) and diesel fuel derived from algae (HRD76), and two conventional counterparts, jet fuel (JP5) and ship diesel (F76). Initial toxicity tests performed on water-accommodated fractions (WAF) from neat fuels partitioned into seawater, using four standard marine species in acute and chronic/sublethal tests, indicate that the alternative fuels are significantly less toxic to marine organisms. PMID:24315182

  12. California's experience with alternative fuel vehicles

    International Nuclear Information System (INIS)

    California is often referred to as a nation-state, and in many aspects fits that description. The state represents the seventh largest economy in the world. Most of California does not have to worry about fuel to heat homes in the winter. What we do worry about is fuel for our motor vehicles, approximately 24 million of them. In fact, California accounts for ten percent of new vehicle sales in the United States each year, much of it used in the transportation sector. The state is the third largest consumer of gasoline in the world, only exceeded by the United States as a whole and the former Soviet Union. California is also a leader in air pollution. Of the nine worst ozone areas in the country cited in the 1990 Clean Air Act Amendments, two areas the Los Angeles Basin and San Diego are located in California. Five of California's cities made the top 20 smoggiest cities in the United States. In reality, all of California's major metropolitan areas have air quality problems. This paper will discuss the beginnings of California's investigations of alternative fuels use in vehicles; the results of the state's demonstration programs; and future plans to improve California's air quality and energy security in the mobile sector

  13. Analysis of thorium and uranium fuel cycles in an iso-breeder lead fast reactor using extended-EQL3D procedure

    International Nuclear Information System (INIS)

    Highlights: ► Extension of EQL3D procedure to calculate radio-toxicity and decay heat. ► Characterization of uranium- and thorium-fueled LFR from BOL to equilibrium. ► Safety improvements for a LFR in a closed thorium cycle. ► Advantages of thorium-fueled LFR in terms of decay heat and radio-toxicity generation. ► Safety, decay heat and radio-toxicity concerns for a Th–Pu beginning-of-life core. - Abstract: Use of thorium in fast reactors has typically been considered as a secondary option, mainly thanks to a possible self-sustaining thorium cycle already in thermal reactors and due to the limited breeding capabilities compared to U–Pu in the fast neutron energy range. In recent years nuclear waste management has become more important, and the thorium option has been reconsidered for the claimed potential to burn transuranic waste and the lower build-up of hazardous isotopes in a closed cycle. To ascertain these claims and their limitations, the fuel cycle isotopic inventory, and associated waste radio-toxicity and decay heat, should be quantified and compared to the case of the uranium cycle using realistic core configurations, with complete recycle of all the actinides. Since the transition from uranium to thorium fuel cycles will likely involve a transuranic burning phase, this transition and the challenges that the evolving fuel actinide composition presents, for instance on reactor feedback parameters, should also be analyzed. In the present paper, these issues are investigated based on core physics analysis of the Lead-cooled Fast Reactor ELSY, performed with the fast reactor ERANOS code and the EQL3D procedure allowing full-core characterization of the equilibrium cycle and the transition cycles. In order to compute radio-toxicity and decay heat, EQL3D has been extended by developing a new module, which has been assessed against ORIGEN-S and is presented here. The capability of the EQL3D procedure to treat full-core 3D geometries allowed to

  14. Maintenance and operation of the US Alternative Fuel Center

    Energy Technology Data Exchange (ETDEWEB)

    Erwin, J.; Ferrill, J.L.; Hetrick, D.L. [Southwest Research Inst., San Antonio, TX (United States)

    1994-08-01

    The Alternative Fuels Utilization Program (AFUP) of the Office of Energy Efficiency and Renewable Energy has investigated the possibilities and limitations of expanded scope of fuel alternatives and replacement means for transportation fuels from alternative sources. Under the AFUP, the Alternative Fuel Center (AFC) was created to solve problems in the DOE programs that were grappling with the utilization of shale oil and coal liquids for transportation fuels. This report covers the first year at the 3-year contract. The principal objective was to assist the AFUP in accomplishing its general goals with two new fuel initiatives selected for tasks in the project year: (1) Production of low-sulfur, low-olefin catalytically cracked gasoline blendstock; and (2) production of low-reactivity/low-emission gasoline. Supporting goals included maintaining equipment in good working order, performing reformulated gasoline tests, and meeting the needs of other government agencies and industries for fuel research involving custom processing, blending, or analysis of experimental fuels.

  15. Standardization of Alternative Fuels. Phase 2

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-08-15

    March 2003 the Executive Committee of the International Energy Agency's Implementing Agreement on Advanced Motor fuels (IEA/AMF) decided to continue annex XXVII 'Standardization of alternative fuels' with a second phase. The purpose of the second phase was to go further in the contacts with the International Organization for Standardization (ISO) as well as the European Committee for Standardization (CEN) and their technical committees, to better understand their needs and to investigate how IEA/AMF could contribute to their work. It was also scheduled to put forward proposals on how IEA/AMF could cooperate with CEN and ISO and their technical committees (TC: s), primarily ISO/TC 28 'Petroleum Products and Lubricants' and CEN/TC 19 'Petroleum Products, Lubricants and Related Products'. The main part of the work in IEA/AMF annex XXVII phase two has focused on personal contacts within CEN/TC 19 and ISO/TC 28, but also on data and information collection from websites and written information. Together with the analysis of this information, the internal organization of a cooperation between IEA/AMF and ISO/TC 28 and of a cooperation between IEA/AMF and CEN/TC 19 have also been discussed and analysed.

  16. Self-Sustaining Thorium Boiling Water Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Greenspan, Ehud [Univ. of California, Berkeley, CA (United States); Gorman, Phillip M. [Univ. of California, Berkeley, CA (United States); Bogetic, Sandra [Univ. of California, Berkeley, CA (United States); Seifried, Jeffrey E. [Univ. of California, Berkeley, CA (United States); Zhang, Guanheng [Univ. of California, Berkeley, CA (United States); Varela, Christopher R. [Univ. of California, Berkeley, CA (United States); Fratoni, Massimiliano [Univ. of California, Berkeley, CA (United States); Vijic, Jasmina J. [Univ. of California, Berkeley, CA (United States); Downar, Thomas [Univ. of Michigan, Ann Arbor, MI (United States); Hall, Andrew [Univ. of Michigan, Ann Arbor, MI (United States); Ward, Andrew [Univ. of Michigan, Ann Arbor, MI (United States); Jarrett, Michael [Univ. of Michigan, Ann Arbor, MI (United States); Wysocki, Aaron [Univ. of Michigan, Ann Arbor, MI (United States); Xu, Yunlin [Univ. of Michigan, Ann Arbor, MI (United States); Kazimi, Mujid [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Shirvan, Koroush [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Mieloszyk, Alexander [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Todosow, Michael [Brookhaven National Lab. (BNL), Upton, NY (United States); Brown, Nicolas [Brookhaven National Lab. (BNL), Upton, NY (United States); Cheng, Lap [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-03-15

    The primary objectives of this project are to: Perform a pre-conceptual design of a core for an alternative to the Hitachi proposed fuel-self- sustaining RBWR-AC, to be referred to as a RBWR-Th. The use of thorium fuel is expected to assure negative void coefficient of reactivity (versus positive of the RBWR-AC) and improve reactor safety; Perform a pre-conceptual design of an alternative core to the Hitachi proposed LWR TRU transmuting RBWR-TB2, to be referred to as the RBWR-TR. In addition to improved safety, use of thorium for the fertile fuel is expected to improve the TRU transmutation effectiveness; Compare the RBWR-Th and RBWR-TR performance against that of the Hitachi RBWR core designs and sodium cooled fast reactor counterparts - the ARR and ABR; and, Perform a viability assessment of the thorium-based RBWR design concepts to be identified along with their associated fuel cycle, a technology gap analysis, and a technology development roadmap. A description of the work performed and of the results obtained is provided in this Overview Report and, in more detail, in the Attachments. The major findings of the study are summarized.

  17. Self-Sustaining Thorium Boiling Water Reactors

    International Nuclear Information System (INIS)

    The primary objectives of this project are to: Perform a pre-conceptual design of a core for an alternative to the Hitachi proposed fuel-self- sustaining RBWR-AC, to be referred to as a RBWR-Th. The use of thorium fuel is expected to assure negative void coefficient of reactivity (versus positive of the RBWR-AC) and improve reactor safety; Perform a pre-conceptual design of an alternative core to the Hitachi proposed LWR TRU transmuting RBWR-TB2, to be referred to as the RBWR-TR. In addition to improved safety, use of thorium for the fertile fuel is expected to improve the TRU transmutation effectiveness; Compare the RBWR-Th and RBWR-TR performance against that of the Hitachi RBWR core designs and sodium cooled fast reactor counterparts - the ARR and ABR; and, Perform a viability assessment of the thorium-based RBWR design concepts to be identified along with their associated fuel cycle, a technology gap analysis, and a technology development roadmap. A description of the work performed and of the results obtained is provided in this Overview Report and, in more detail, in the Attachments. The major findings of the study are summarized.

  18. A review of the current status of nuclear data for major and minor isotopes of thorium fuel cycle

    International Nuclear Information System (INIS)

    In this paper, we present a critical overview of the status of the available nuclear data of isotopes of thorium fuel cycle, viz., 230Th, 232Th, 231Pa, 233Pa, 232U, 233U and 234U. Induced in the main body of the paper is a critical analysis of information contained in the two basic evaluated nuclear data files JENDL-3.2 and ENDF/B-VI (Rev.5) recently released by the IAEA/NDS as a result of truly international efforts. In some of the cases, the information and data given in EXFOR is examined to get an idea of the status of measured nuclear data of these isotopes. Some comments regarding gaps in experimental data as of 1999 are included in the discussion. Most of these experimental data were those generated two decades ago. In addition, generally, these experimental data are very limited in comparison to the voluminous nuclear data generated for the uranium-plutonium cycle. Experimental data is absent in most of the cases and, in such cases, evaluated cross sections in the two basic evaluated nuclear data files JENDL-3.2 and ENDF/B-VI(Rev.5) are based upon theoretical models and nuclear systematics. Some of these differences between JEF-2.2 and its source ENDF/B-V that were carried over to ENDF/B-VI(Rev.5) are explained. The role and the importance of 231Pa and 233Pa in the thorium fuel cycle in advanced concepts such as the Energy Amplifier are mentioned. New calculations of criticality property of 231Pa and 233Pa are presented using the neutron reaction data of JENDL-3.2 and ENDF/B-VI(Rev.5). The possible influence of 230Th is examined with respect to its cross sections and production of 231Pa in a typical Indian PHWR environment. The quality assurance in design and safety studies in nuclear energy in the next few decades and centuries require new and improved data with high accuracy and energy resolution. As a starter, the nuclear data of the set of isotopes of thorium fuel cycle discussed in this paper is a challenging sample for consideration as a trial project

  19. A road map for the realization of global-scale thorium breeding fuel cycle by single molten-fluoride flow

    International Nuclear Information System (INIS)

    For global survival in this century, we urgently need to launch a completely new global nuclear fission industry. To get worldwide public acceptance of nuclear energy, improvements are essential not only on safety, radio-waste management and economy but also especially nuclear proliferation resistance and safeguards. However, such global fission industry cannot replace the present fossil fuel industry in the next 50 years, unless the doubling-time of nuclear energy is less than 10 years, preferably 5-7 years. Such a doubling-time cannot be established by any kind of classical 'Fission Breeding Power Station' concept. We need a symbiotic system which couples fission power reactors with a system which can convert fertile thorium to fissile U-233, such as a spallation or D/T fusion (if and when it becomes available). For such a purpose, THORIMS-NES [Thorium Molten-Salt Nuclear Energy Synergetic System] has been proposed, which is composed of simple thermal fission power stations (FUJI) and fissile producing Accelerator Molten-Salt Breeder (AMSB). Its system functions are very ambitious, delicate and complex, but can be realized in the form of simple hardware applying the multifunctional 'single-phase molten-fluoride' circulation system. This system has no difficulties relating with 'radiation-damage', 'heat-removal' and 'chemical processing' owing to the simple 'idealistic ionic liquid' character. FUJI is size-flexible (economical even in smaller sizes), fuel self-sustaining without any continuous chemical processing and without core-graphite replacement, and AMSB is based on a single-fluid molten-salt target/blanket concept, which solves most engineering difficulties such as radiation-damage, heat-removal etc., except high-current proton accelerator development. Several AMSBs are accommodated in the regional centers (several ten sites in the world) with batch chemical processing plants including radio-waste management. The integrated thorium breeding fuel cycle is

  20. Nickel based alloys compatibility with fuel salts for molten salt reactor with thorium and uranium support

    International Nuclear Information System (INIS)

    R and D on molten salt reactors (MSR) in Europe are concentrated now on fast/intermediate spectrum concepts which were recognised as long-term alternative to solid fuelled fast reactors due to their attractive features: strong negative feedback coefficients, easy in-service inspection, and simplified fuel cycle. For high-temperature MSR corrosion of the metallic container alloy in primary circuit is the primary concern. Key problem receiving current attention include surface fissures in Ni-based alloys probably arising from fission product tellurium attack. This paper summarises results of corrosion tests conducted recently to study effect of oxidation state in selected fuel salts on tellurium attack and to develop means of controlling tellurium cracking in the special Ni - based alloys recently developed for large power units: molten salt actinide recycler and transmuter (MOSART) and molten salt fast reactor (MSFR). Tellurium corrosion of Ni-based alloys was tested in the temperature range from 730 deg. C up to 800 deg. C in stressed and unloaded conditions with fuel LiF-BeF2-UF4 and LiF-BeF2-ThF4-UF4 salt mixtures at different [U(IV)]/[U(III)] ratios from 0.7 up to 500. Following Russian and French Ni-based alloys (in mass%): HN80M-VI (Mo-12, Cr-7.6, Nb-1.5), HN80MTY (Mo-13, Cr-6.8, Al-1.1, Ti-0.9), HN80MTW (Mo-9.4, Cr-7.0, Ti-1.7, W-5.5) and EM-721 (W-25.2, Cr-5.7, Ti-0.17) were used for the study in the corrosion facility. The HN80MTY alloy has shown the best resistance against Te cracking and after test mechanical properties. (authors)

  1. Development of simple method to incorporate out-of-core cooling effect on thorium conversion in multi-pass fueled reactor and investigation on characteristics of the effect

    International Nuclear Information System (INIS)

    Highlights: • I proposed simple method based on analytical approach. • I applied this method to MVP-BURN calculations without a code modification. • I estimated conversion efficiencies based on this method. • I compared the conversion efficiencies of MSBR and PBMR. - Abstract: Development of a simple method to incorporate the out-of-core cooling effect on the thorium conversion in multi-pass fueled reactors and investigation on characteristics of the effect have been undertaken. For multi-pass fueled reactors, such as Molten Salt Breeder Reactor (MSBR) and Pebble-Bed Modular Reactor (PBMR), fuel moves in the core and exits from the core. The produced nuclides also decay out of the core, which should be considered for core characteristics when needed. In the present study, 233Pa is selected to evaluate the thorium conversion accurately. To take the effect into account, in the present study, an effective decay constant is proposed to make equilibrium concentration of 233Pa without out-of-core cooling equal to that with out-of-core cooling. With the effective decay constant, the out-of-core cooling effect can be incorporated even with the code system using macroscopic cross sections generated by cell burn-up calculations without any code modification. In addition, the characteristics of out-of-core cooling effect for the thorium conversion are evaluated for thorium fueled reactors MSBR and PBMR. It is concluded that the out-of-core cooling effect is suitable for MSBR to enhance thorium conversion because of the fast flow rate of fuel salt. On the other hand, the effect is neither important nor realistic to employ for PBMR because the in-core residence time of approximately 100 days is longer than the half-life of 233Pa of 27.0 days, and the effect cannot improve the conversion ratio significantly

  2. Maintenance and operation of the USDOE Alternative Fuel Center

    Energy Technology Data Exchange (ETDEWEB)

    Erwin, J.; Moulton, D.S.; Hetrick, D.L. [Southwest Research Inst., San Antonio, TX (United States)

    1994-08-01

    The Alternative Fuels Utilization Program (AFUP) of the Office of Energy Efficiency and Renewable Energy has investigated the possibilities and limitations of expanded scope of fuel alternatives and replacement means for transportation fuels from alternative sources. Under the AFUP, the Alternative Fuel Center (AFC) was created to solve problems in the DOE programs that were grappling with the utilization of shale oil and coal liquids for transportation fuels. In year one of this contract, a timeline was set to coordinate uses and operations of the AFC hydrogenation pilot plant among test fuels production project work, facility maintenance, other government work, and work for industry for second-generation operations. In year two, consistent with assisting the AFUP in accomplishing its general goals, the work was done with fuel producers, regulators, and users in mind. AFC capabilities and results were disseminated through tours and outside presentations.

  3. U.S. leans toward denatured thorium cycle

    International Nuclear Information System (INIS)

    Denatured thorium appears to be the most promising among the nonproliferating alternatives to the plutonium cycle, which the Carter Administration is trying to cancel. Criteria for a better system include uranium utilization comparable to current light water reactors and minimal separation of fissile material into the waste stream. Comparisons with other systems conclude that thorium is preferable because it can lead to an acceptable fast breeder. The thorium cycle can be placed in energy centers for sensitive facilities and can also be introduced into ongoing light water systems. Reprocessing can be handled in the centers, where thorium can be mixed with plutonium for use in reactors within the center, while light water reactors operate on the outside. Any fuel leaving the center would be unsuitable for weapons. Later adaptation to in-center fast breeders will extend energy supplies, although a thorium breeder will be less efficient than a plutonium fast breeder. Denatured thorium is a technical answer to a complex political problem, but those in the nuclear industry see the U.S. goal of a nonproliferating fuel as futile in the light of world politics and breeder efforts in other countries

  4. Economy of uranium resources in a three-component reactor fleet with mixed thorium/uranium fuel cycles

    International Nuclear Information System (INIS)

    The potential for minimizing uranium consumption by using a reactor fleet with three different components and mixed thorium/uranium cycles has been investigated with a view to making nuclear power a more sustainable and cleaner means of generating energy. Mass flows of fissile material have been calculated from burnup simulations at the core-equivalent assembly level for each of the three components of the proposed reactor fleet: plutonium extracted from the spent fuel of a standard pressurised water reactor (first component) is converted to 233U in an advanced boiling water reactor (second component) to feed a deficit of multi-recycled 233U needed for the Th/233U fuel of the light/heavy water reactor (third component) which has a high breeding ratio. Although the proposed fleet cannot breed its own fuel, we show that it offers the possibility for substantial economy of uranium resources without the need to resort to innovative (and costly) reactor designs. A very high fleet breeding ratio is achieved by using only currently existing water-based reactor technology and we show that such three-component systems will become economically competitive if the uranium price becomes sufficiently high (> 300 $/kg). Another major advantage of such systems is a corresponding substantial decrease in production of minor actinide waste. (authors)

  5. Alternative Fuels for Marine and Inland Waterways: An exploratory study

    OpenAIRE

    MOIRANGTHEM KAMALJIT

    2016-01-01

    Alternative fuels for marine transport can play a crucial role in decarbonising the shipping sector and ultimately contribute towards climate change goals. Market penetration by alternative fuels have already begun with ship builders, engine manufacturers and classification bodies by introducing greener ships running on cleaner fuels. This can be attributed in large part to the MARPOL (International Convention for the Prevention of Pollution from Ships) regulations in place since the 1970s an...

  6. Emission Control Cost-Effectiveness of Alternative-Fuel Vehicles

    OpenAIRE

    Wang, Quanlu; Sperling, Daniel; Olmstead, Janis

    1993-01-01

    Although various legislation and regulations have been adopted to promote the use of alternative-fuel vehicles for curbing urban air pollution problems, there is a lack of systematic comparisons of emission control cost-effectiveness among various alternative-fuel vehicle types. In this paper, life-cycle emission reductions and life-cycle costs were estimated for passenger cars fueled with methanol, ethanol, liquified petroleum gas, compressed natural gas, and electricity. Vehicle emission es...

  7. Research of natural resources saving by design studies of Pressurized Light Water Reactors and High Conversion PWR cores with mixed oxide fuels composed of thorium/uranium/plutonium

    International Nuclear Information System (INIS)

    Within the framework of innovative neutronic conception of Pressurized Light Water Reactors (PWR) of 3. generation, saving of natural resources is of paramount importance for sustainable nuclear energy production. This study consists in the one hand to design high Conversion Reactors exploiting mixed oxide fuels composed of thorium/uranium/plutonium, and in the other hand, to elaborate multi-recycling strategies of both plutonium and 233U, in order to maximize natural resources economy. This study has two main objectives: first the design of High Conversion PWR (HCPWR) with mixed oxide fuels composed of thorium/uranium/plutonium, and secondly the setting up of multi-recycling strategies of both plutonium and 233U, to better natural resources economy. The approach took place in four stages. Two ways of introducing thorium into PWR have been identified: the first is with low moderator to fuel volume ratios (MR) and ThPuO2 fuel, and the second is with standard or high MR and ThUO2 fuel. The first way led to the design of under-moderated HCPWR following the criteria of high 233U production and low plutonium consumption. This second step came up with two specific concepts, from which multi-recycling strategies have been elaborated. The exclusive production and recycling of 233U inside HCPWR limits the annual economy of natural uranium to approximately 30%. It was brought to light that the strong need in plutonium in the HCPWR dedicated to 233U production is the limiting factor. That is why it was eventually proposed to study how the production of 233U within PWR (with standard MR), from 2020. It was shown that the anticipated production of 233U in dedicated PWR relaxes the constraint on plutonium inventories and favours the transition toward a symbiotic reactor fleet composed of both PWR and HCPWR loaded with thorium fuel. This strategy is more adapted and leads to an annual economy of natural uranium of about 65%. (author)

  8. Determination of uranium and thorium in monazite bearing sand by gamma ray spectrometry

    International Nuclear Information System (INIS)

    Monazite is one of the most important natural geological mineral due to the presence of heavy metals, rare earth and natural radioactive elements. Monazite is also an important ore for thorium, lanthanum, and cerium. It is very important to assess the concentration of uranium and thorium in various monazite samples observed in Indian coasts and their relative abundance. In addition to thorium, availability of uranium in monazite is also of interest because of an alternate source for the uranium fuel cycle operation going on in our country. The relative abundance of uranium in monazite bearing sands can be represented by the activity ratio of uranium to thorium in the samples. In the present study an attempt has been made to estimate the activity ratios of uranium to thorium in some of the monazite bearing beach sands collected from our coastal regions by using high resolution gamma ray spectrometry techniques

  9. Impact of Thorium Capture Cross Section Uncertainty on the Thorium Utilized ADS Reactivity Calculation

    OpenAIRE

    Thanh Mai Vu; Takanori Kitada

    2014-01-01

    Recently, the researches on fast neutron spectrum system utilized thorium fuel are widely conducted. However, the recent thorium cross section libraries are limited compared to uranium cross section libraries. The impact of thorium cross section uncertainty on thorium fuel utilized accelerator driven system (ADS) reactivity calculation is estimated in this study. The uncertainty of the keff caused by 232Th capture cross section of JENDL-4.0 is about 1.3%. The uncertainty of JENDL-4.0 is neede...

  10. Techno-economic assessment of thorium power in Canada

    International Nuclear Information System (INIS)

    Highlights: • Costs of replacing uranium in Canada’s nuclear reactors with thorium evaluated. • Results show a thorium plant to be more financially lucrative than a uranium plant. • Results were most sensitive to electricity price, then capital and decommissioning cost. • Abatement cost analysis showed nuclear power offers cost savings over fossil fuels. - Abstract: Thorium fission is a large yet relatively unexplored renewable energy source and could help feed increasing energy demands. An analysis was performed on the feasibility of replacing the uranium in Canada’s nuclear reactors with thorium. Thorium only exists as a fertile isotope, and so an external fissile source such as 235U, 233U, or 239Pu is required to stimulate the fission process. A uranium plant and a similar thorium-fuelled plant were compared over a 40 year operational life based on a comprehensive economic analysis. The results from the economic analysis were used to estimate the greenhouse gas (GHG) abatement cost compared to the coal and natural gas-based power. The economic analysis determined that a thorium plant is more financially lucrative in Canada than a uranium plant. An abatement cost assessment in relation to gas-fired and coal-fired power plants demonstrated that nuclear power offers a cost savings per tonne of CO2 equivalent greenhouse gas (GHG) when compared to both fossil fuel alternatives. From the values determined for a plant potentially fuelled on thorium, the abatement cost when compared to the coal-fired and gas-fired plants is −$10.4/tonne-CO2eq and −$15.7/tonne-CO2eq, respectively

  11. Use of alternative fuels in the Polish cement industry

    Energy Technology Data Exchange (ETDEWEB)

    Mokrzycki, Eugeniusz; Uliasz-Bochenczyk, Alicja [Polish Academy of Sciences, Mineral and Energy Economy Research Inst., Krakow (Poland); Sarna, Mieczyslaw [Lafarge Cement Polska S.A., Malogoszcz (Poland)

    2003-02-01

    Alternative fuels are made up of mixtures of different wastes, such as industrial, municipal and hazardous wastes. These fuels need to have an appropriate chemical energy content which depends on the type of components and their organic content. An industry that is particularly well suited to the employment of alternative fuels is the cement industry. There are a number of factors that promote the use of alternative fuels in cement kilns. Of these factors, the most notable are: the high temperatures developed, the appropriate kiln length, the long period of time the fuel stays inside the kiln and the alkaline environment inside the kiln. There are a number of countries that use their own alternative fuels in cement plants. These fuels have different trade names and they differ in the amounts and the quality of the selected municipal and industrial waste fractions used. The fuels used should fall within the extreme values of parameters such as: minimum heating value, maximum humidity content, and maximum content of heavy and toxic metals. Cement plants in Poland also use alternative fuels. Within the Lafarge Group, the cement plants owned by Lafarge Poland Ltd. have initiated activities directed at promoting the wider use of alternative fuels. There are a number of wastes that can be incinerated as fuel in cement plants. Some that can be mentioned are: selected combustible fractions of municipal wastes, liquid crude-oil derived wastes, car tyres, waste products derived from paint and varnish production, expired medicines from the pharmaceutical industry and others. The experience gained by the cement plants of Lafarge Cement Poland Ltd confirms that such activities are economically and ecologically beneficial. The incineration of alternative fuels in cement plants is a safe method for the utilisation of waste that is ecologically friendly and profitable for the industrial plants and society alike. (Author)

  12. Methanol, Natural Gas, and the Development of Alternative Transportation Fuels

    OpenAIRE

    Kliman, M.L.

    1983-01-01

    The potential for methanol as a motor fuel, particularly when it is produced from natural gas is examined. Diverse information related to methanol fuel development is gathered together and the process by which such a new fuel market would evolve is considered. It is concluded that methanol has the capacity to be a significant alternative fuel, but that the realization of that capacity is not yet imminent.

  13. An evaluation of the alternative transport fuel policies for Turkey

    International Nuclear Information System (INIS)

    The search for alternative fuels and new fuel resources is a top priority for Turkey, as is the case in the majority of countries throughout the world. The fuel policies pursued by governmental or civil authorities are of key importance in the success of alternative fuel use, especially for widespread and efficient use. Following the 1973 petroleum crisis, many users in Turkey, especially in transportation sector, searched for alternative fuels and forms of transportation. Gasoline engines were replaced with diesel engines between the mid-1970s and mid-1980s. In addition, natural gas was introduced to the Turkish market for heating in the early 1990s. Liquid petroleum gas was put into use in the mid-1990s, and bio-diesel was introduced into the market for transportation in 2003. However, after long periods of indifference governmental action, guidance and fuel policies were so weak that they did not make sense. Entrepreneurs and users experienced great economical losses and lost confidence in future attempts to search for other possible alternatives. In the present study, we will look at the history of alternative fuel use in the recent past and investigate the alternative engine fuel potential of Turkey, as well as introduce possible future policies based on experience. (author)

  14. The environment and the use of alternative fuels

    International Nuclear Information System (INIS)

    The contribution of the Netherlands Energy Research Foundation (ECN) to the ANWB symposium on alternative fuels and techniques concerns the necessity to use alternatives to reduce CO2 emissions, the importance of system integration, and a discussion of the strong and weak points with regard to the introduction of the fuel alternatives in the Netherlands. First attention is paid to the greenhouse effect (CO2 emissions) of the use of fuels. Options to reduce CO2 emission from automobiles are mentioned. Than several alternative fuels and accompanying techniques, and their impact on the CO2 emission, are discussed: diesel, liquid petroleum gas (LPG), compressed natural gas (CNG), methanol, ethanol, rapeseed, electricity, and hydrogen. The possibilities to reduce CO2 emission in the Netherlands can be calculated by means of the Energy and Materials Scenarios (EMS). For several aspects assessments are given for the above-mentioned alternatives: availability of technology, ease of fuel storage, risk of use, impact on the city climate, full fuel cycle CO2 emission, costs, and reserves. These aspects can be considered as valid for most of the industrialized countries. For the Netherlands two other aspects have been assessed: the interest of the oil industry in the introduction of alternative fuels, the availability of the alternatives in the Netherlands. 5 figs., 6 tabs., 10 refs

  15. Analysis of Alternative Fuels in Automotive Powertrains

    OpenAIRE

    Gunnarsson, Andreas

    2009-01-01

    The awareness of the effect emissions have on the environment and climate has risen in the last decades. This has caused strict regulations of greenhouse gas emissions. Greenhouse gases cause global warming which may have devastating environmental effects. Most of the fuels commercially available today are fossil fuels. There are two major effects of using fuels with fossil origin; the source will eventually drain and the usage results in an increase of greenhouse gases in the atmosphere. Fue...

  16. Emergency fuels utilization guidebook. Alternative Fuels Utilization Program

    Energy Technology Data Exchange (ETDEWEB)

    1980-08-01

    The basic concept of an emergency fuel is to safely and effectively use blends of specification fuels and hydrocarbon liquids which are free in the sense that they have been commandeered or volunteered from lower priority uses to provide critical transportation services for short-duration emergencies on the order of weeks, or perhaps months. A wide variety of liquid hydrocarbons not normally used as fuels for internal combustion engines have been categorized generically, including limited information on physical characteristics and chemical composition which might prove useful and instructive to fleet operators. Fuels covered are: gasoline and diesel fuel; alcohols; solvents; jet fuels; kerosene; heating oils; residual fuels; crude oils; vegetable oils; gaseous fuels.

  17. DUPIC technology as an alternative for closing nuclear fuel cycle

    International Nuclear Information System (INIS)

    The study of DUPIC technology as an alternative for closing nuclear fuel cycle has been carried out. The goal of this study is to understand the DUPIC technology and its possibility as an alternative technology for closing nuclear fuel cycle. DUPIC (Direct Use of PWR spent fuel In CANDU) is a utilization of PWR spent fuel to reprocess and fabricate become DUPIC fuel as nuclear fuel of Candu reactor. The synergy utilization is based on the fact that fissile materials contained in the PWR spent fuel is about twice as much as that in Candu fuel. Result of the study indicates that DUPIC is an alternative promising technology for closing nuclear fuel cycle. The DUPIC fuel fabrication technology of which the major process is the OREOX dry processing, is better than the conventional reprocessing technology of PUREX. The OREOX dry processing has no capability to separate fissile plutonium, thus give the impact of high nuclear proliferation resistance. When compared to once through cycle, it gives advantages of uranium saving of about 20% and spent fuel accumulation reduction of about 65%. Economic analysis indicates that the levelized cost of DUPIC cycle is cheaper by 0.073 mill$/kwh than that of once through cycle. (author)

  18. Peculiar Features of Burning Alternative Motor Fuels

    Directory of Open Access Journals (Sweden)

    M. Assad

    2006-01-01

    Full Text Available Some peculiar features of air-hydrogen mixture combustion process in a modeling combustion chamber are given in the paper. Dependences of burning duration of various fuel types on initial pressure have been obtained. The paper considers dynamics of changes in pressure and ignition rate of some fuel types in the combustion chamber.

  19. Ontario Select Committee on Alternative Fuel Sources : Final Report

    International Nuclear Information System (INIS)

    On June 28, 2001, the Ontario Legislative Assembly appointed the Select Committee an Alternative Fuel Sources, comprised of representatives of all parties, with a broad mandate to investigate, report and offer recommendations with regard to the various options to support the development and application of environmentally sustainable alternatives to the fossil fuel sources already existing. The members of the Committee elected to conduct extensive public hearings, conduct site visits, attend relevant conferences, do some background research to examine a vast number of alternative fuel and energy sources that could be of relevance to the province of Ontario. A discussion paper (interim report) was issued by the Committee in November 2001, and the present document represents the final report, containing 141 recommendations touching 20 topics. The information contained in the report is expected to assist in the development and outline of policy and programs designed to specifically support alternative fuels and energy sources and applicable technologies. Policy issues were discussed in Part A of the report, along with the appropriate recommendations. The recommendations on specific alternative fuels and energy sources were included in Part B of the report. It is believed that the dependence of Ontario on traditional petroleum-based fuels and energy sources can be reduced through aggressive action on alternative fuels and energy. The benefits of such action would be felt in the area of air quality, with social, and economic benefits as well. 3 tabs

  20. Neutronic analysis of PROMETHEUS reactor fueled with various compounds of thorium and uranium

    International Nuclear Information System (INIS)

    In this study, neutronic performance of the DT driven blanket in the PROMETHEUS-H (heavy ion) fueled with different fuels, namely, ThO2, ThC, UO2, UC, U3Si2 and UN is investigated. Helium is used as coolant, and SiC is used as cladding material to prevent fission products from contaminating coolant and direct contact fuel with coolant in the blanket. Calculations of neutronic data per DT fusion neutron are performed by using SCALE 4.3 Code. M (energy multiplication factor) changes from 1.480 to 2.097 depending on the fuel types in the blanket under resonance-effect. M reaches the highest value in the blanket fueled with UN. Therefore, the investigated reactor can produce substantial electricity in situ. UN has the highest value of 239Pu breeding capability among the uranium fuels whereas UO2 has the lowest one. 239Pu production ratio changes from 0.119 to 0.169 according to the uranium fuel types, and 233U production values are 0.125 and 0.140 in the blanket fueled with ThO2 and ThC under resonance-effect, respectively. Heat production per MW (D,T) fusion neutron load varies from 1.30 to 7.89 W/cm3 in the first row of fissile fuel breeding zone depending on the fuel types. Heat production attains the maximum value in the blanket fueled with UN. Values of TBR (tritium breeding ratio) being one of the most important parameters in a fusion reactor are greater than 1.05 for all type of fuels so that tritium self-sufficiency is maintained for DT fusion driver. Values of peak-to-average fission power density ratio, Γ, are in the range of 1.390 and ∼1.476 depending on the fuel types in the blanket. Values of neutron leakage out of the blanket for all fuels are quite low due to SiC reflector. The maximum neutron leakage is only ∼0.025. Consequently, for all cases, the investigated reactor has high neutronic performance and can produce substantial electricity in situ, fissile fuel and tritium required for (D,T) fusion reaction

  1. Non-Gasoline Alternative Fueling Stations

    Data.gov (United States)

    Department of Homeland Security — Through a nationwide network of local coalitions, Clean Citiesprovides project assistance to help stakeholders in the public and private sectors deploy alternative...

  2. Potential of thorium based fuel cycles to constrain plutonium and reduce long lived waste toxicity. Final report of a co-ordinated research project 1995-2001

    International Nuclear Information System (INIS)

    The Co-ordinated Research Project examined the different fuel cycle options in which plutonium can be recycled with thorium to incinerate the burner. The potential of the thorium-matrix has been examined through computer simulations. Each participating country has chosen his own cycle, and different cycles were compared though certain predefined parameters (e.g. annual reduction of plutonium stockpiles.) The toxicity accumulation and the transmutation potential of thorium-based cycles for current and innovative nuclear power reactors were investigated. Four types of reactors were investigated, Israel, Republic of Korea, Russian Federation, and the USA have done research on LWRs; China, the Netherlands and Germany have studied plutonium burning in Modular HTRs; India studied the respective potential of the PHWR, and Japan that of the MSR. Two characteristic values - aiming at two different optimization goals - have been used to describe the effectiveness of plutonium incineration in the different reactors: the amount of plutonium, which is burned per unit of produced electric energy and the relation between the amount of plutonium, which is burned during the lifetime of the fuel elements, and the amount of plutonium, which is residual in the unloaded fuel

  3. Fuels and alternative propulsion in Germany

    International Nuclear Information System (INIS)

    The transportation sector is one of the first responsible of the air pollution in Germany. The kyoto protocol and the european directive led the german Government to set about some measures. To encourage the petroleum industry to develop classical fuels/biofuels mixing, the government exempted from taxes until 2020 the biofuels part. The Government decided also financial incentives for diesel vehicles equipped with particles filters. Among the different fuels, the document presents the advantages and disadvantages of the hydrogen fuels and the hybrid motors. (A.L.B.)

  4. INDOT Fleet Management Strategies: Implementing Alternative Fuel Technologies

    OpenAIRE

    Rudolph, Joseph

    2012-01-01

    This session will discuss INDOT’s initiative to introduce vechicles fueled by propane and compressed natural gas (CNG) to their fleet. Successes to date will be shared as well as recommendations for fleet managers considering these alternative technologies.

  5. Alternative Fuel and Advanced Technology Commercial Lawn Equipment (Brochure)

    Energy Technology Data Exchange (ETDEWEB)

    2014-10-01

    The U.S. Department of Energy's Clean Cities program produced this guide to help inform the commercial mowing industry about product options and potential benefits. This guide provides information about equipment powered by propane, ethanol, compressed natural gas, biodiesel, and electricity, as well as advanced engine technology. In addition to providing an overview for organizations considering alternative fuel lawn equipment, this guide may also be helpful for organizations that want to consider using additional alternative fueled equipment.

  6. Alternative Fuel and Advanced Technology Commercial Lawn Equipment

    Energy Technology Data Exchange (ETDEWEB)

    None

    2014-10-10

    The U.S. Department of Energy's Clean Cities program produced this guide to help inform the commercial mowing industry about product options and potential benefits. This guide provides information about equipment powered by propane, ethanol, compressed natural gas, biodiesel, and electricity, as well as advanced engine technology. In addition to providing an overview for organizations considering alternative fuel lawn equipment, this guide may also be helpful for organizations that want to consider using additional alternative fueled equipment.

  7. Alternatives to traditional transportation fuels 1994. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-02-01

    In this report, alternative and replacement fuels are defined in accordance with the EPACT. Section 301 of the EPACT defines alternative fuels as: methanol, denatured ethanol, and other alcohols; mixtures containing 85% or more (or such other percentage, but not less than 70%, as determined by the Secretary of Energy, by rule, to provide for requirements relating to cold start, safety, or vehicle functions) by volume of methanol, denatured ethanol, and other alcohols with gasoline or other fuels; natural gas; liquefied petroleum gas; hydrogen; coal-derived liquid fuels; fuels (other than alcohol) derived from biological materials; electricity (including electricity from solar energy); and any other fuel the Secretary determines, by rule, is substantially not petroleum and would yield substantial energy security benefits and substantial environmental benefits. The EPACT defines replacement fuels as the portion of any motor fuel that is methanol, ethanol, or other alcohols, natural gas, liquefied petroleum gas, hydrogen, coal-derived liquid fuels, fuels (other than alcohol) derived from biological materials, electricity (including electricity from solar energy), ethers, or any other fuel the Secretary of Energy determines, by rule, is substantially not petroleum and would yield substantial energy security benefits and substantial environmental benefits. This report covers only those alternative and replacement fuels cited in the EPACT that are currently commercially available or produced in significant quantities for vehicle demonstration purposes. Information about other fuels, such as hydrogen and biodiesel, will be included in later reports as those fuels become more widely used. Annual data are presented for 1992 to 1996. Data for 1996 are based on plans or projections for 1996.

  8. Expectation dynamics: Ups and downs of alternative fuels

    Science.gov (United States)

    Konrad, Kornelia

    2016-03-01

    The transport sector must undergo radical changes if it is to reduce its carbon emissions, calling for alternative vehicles and fuel types. Researchers now analyse the expectation cycles for different fuel technologies and draw lessons for the role of US policy in supporting them.

  9. Effect of fuel cycle alternatives on nuclear waste management

    International Nuclear Information System (INIS)

    The nuclear fuel cycle alternatives considered here and their corresponding material flowsheets are: Pressurized water reactor (PWR) with no fuel reprocessing; PWR with reprocessing for uranium recycle and plutonium storage; PWR with reprocessing for uranium recycle and self-generated plutonium recycle; and high-temperature gas-cooled reactor with uranium recycle

  10. Characteristics of Modular Fast Reactor SVBR-100 Using Thorium-Uranium (233) Fuel

    International Nuclear Information System (INIS)

    Conclusions: • The performed computations for three different types of fuel (oxide , nitride and metallic), have revealed that maximum of uranium-233 breeding ratio, which equals to 0.9, is achieved when nitride type of fuel is used. • Adding breeding zones or increasing of the core dimensions result in increasing uranium-233 breeding ratio (up to BR = 0,97 or BR = 0,96 respectively). • There is opportunity of using plutonium as initial fissile isotope to implement U-Th-Pu fuel cycle. Breeding ratio is assessed by 0,98 if nitride fuel composition (Th+Pu)N with effective density of 12.5 is used. • The obtained data have demonstrated that both for U-Th FC and U-Th-Pu FC there is an opportunity to achieve a value of U-233 BR to be over unity when using the breeding zones and slightly increased the core dimensions

  11. Engine Materials Compatibility with Alternate Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Thomson, Jeffery K [ORNL; Pawel, Steven J [ORNL; Wilson, Dane F [ORNL

    2013-05-01

    The compatibility of aluminum and aluminum alloys with synthetic fuel blends comprised of ethanol and reference fuel C (a 50/50 mix of toluene and iso-octane) was examined as a function of water content and temperature. Commercially pure wrought aluminum and several cast aluminum alloys were observed to be similarly susceptible to substantial corrosion in dry (< 50 ppm water) ethanol. Corrosion rates of all the aluminum materials examined were accelerated by increased temperature and ethanol content in the fuel mixture, but inhibited by increased water content. Pretreatments designed to stabilize passive films on aluminum increased the incubation time for onset of corrosion, suggesting film stability is a significant factor in the mechanism of corrosion.

  12. Engine Materials Compatability with Alternative Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Pawel, Steve [Oak Ridge National Laboratory; Moore, D. [USCAR

    2013-04-05

    The compatibility of aluminum and aluminum alloys with synthetic fuel blends comprised of ethanol and reference fuel C (a 50/50 mix of toluene and iso-octane) was examined as a function of water content and temperature. Commercially pure wrought aluminum and several cast aluminum alloys were observed to be similarly susceptible to substantial corrosion in dry (< 50 ppm water) ethanol. Corrosion rates of all the aluminum materials examined were accelerated by increased temperature and ethanol content in the fuel mixture, but inhibited by increased water content. Pretreatments designed to stabilize passive films on aluminum increased the incubation time for onset of corrosion, suggesting film stability is a significant factor in the mechanism of corrosion.

  13. Conversion of fuel hulls to zirconate ion exchangers for stabilization of wastes from the thorium fuel cycle

    International Nuclear Information System (INIS)

    A conceptual reprocessing and waste management scheme for Zircaloy clad ThO2 fuel was formulated to eliminate problems associated with concurrent dissolution of fuel and cladding in the conventional chop-leach headend step. These problems are avoided by use of a modified headend step to form oxide fuel and cladding process streams. A chlorinating agent then converts the cladding hulls and adhering fuel into volatile and nonvolatile chloride fractions. The former product is processed, by use of the Zircaloy conversion process, to form an inorganic ion exchange material and combined with HLLW from subsequent fuel reprocessing to form a stable and refractory waste form. The nonvolatile chloride fraction would be recovered, processed to remove chloride ions, and recombined with the main oxide fuel process stream for further treatment by use of the Thorex process

  14. Effect of Alternative Fuels on SCR Chemistry

    OpenAIRE

    Faramarzi, Simin

    2012-01-01

    In the time line of world industrial age, the most important era begins in the late 18th century when the use of fossil fuels was growing intensively. This approach has continued and developed up to the 20th century. Besides, this trend has had side effects like polluting environment. Air pollution is one of the critical issues nowadays that stems from using hydrocarbon fuels. One type of the problematic compounds in polluting air is nitrogen oxides that can be produced in combustion process ...

  15. Certification of alternative aviation fuels and blend components

    Energy Technology Data Exchange (ETDEWEB)

    Wilson III, George R. (Southwest Research Institute, 6220 Culebra Road, San Antonio, Texas 78238 (United States)); Edwards, Tim; Corporan, Edwin (United States Air Force Research Laboratory, Wright-Patterson Air Force Base, Ohio 45433 (United States)); Freerks, Robert L. (Rentech, Incorporated, 1331 17th Street, Denver, Colorado 80202 (United States))

    2013-01-15

    Aviation turbine engine fuel specifications are governed by ASTM International, formerly known as the American Society for Testing and Materials (ASTM) International, and the British Ministry of Defence (MOD). ASTM D1655 Standard Specification for Aviation Turbine Fuels and MOD Defence Standard 91-91 are the guiding specifications for this fuel throughout most of the world. Both of these documents rely heavily on the vast amount of experience in production and use of turbine engine fuels from conventional sources, such as crude oil, natural gas condensates, heavy oil, shale oil, and oil sands. Turbine engine fuel derived from these resources and meeting the above specifications has properties that are generally considered acceptable for fuels to be used in turbine engines. Alternative and synthetic fuel components are approved for use to blend with conventional turbine engine fuels after considerable testing. ASTM has established a specification for fuels containing synthesized hydrocarbons under D7566, and the MOD has included additional requirements for fuels containing synthetic components under Annex D of DS91-91. New turbine engine fuel additives and blend components need to be evaluated using ASTM D4054, Standard Practice for Qualification and Approval of New Aviation Turbine Fuels and Fuel Additives. This paper discusses these specifications and testing requirements in light of recent literature claiming that some biomass-derived blend components, which have been used to blend in conventional aviation fuel, meet the requirements for aviation turbine fuels as specified by ASTM and the MOD. The 'Table 1' requirements listed in both D1655 and DS91-91 are predicated on the assumption that the feedstocks used to make fuels meeting these requirements are from approved sources. Recent papers have implied that commercial jet fuel can be blended with renewable components that are not hydrocarbons (such as fatty acid methyl esters). These are not allowed blend

  16. Thorium-based mixed oxide fuel in a pressurized water reactor: A beginning of life feasibility analysis with MCNP

    International Nuclear Information System (INIS)

    Highlights: • Thorium based MOX fuel beginning of life feasibility analysis with MCNP. • Minimum impact MOX enrichment and core configuration was determined. • Determination of hot channel for MOX core. • Analysis of safety parameters and comparison with LEU core was performed. • Advantages and challenges for MOX core were discussed. - Abstract: Thorium is an asset the nuclear industry does not use, and plutonium is a liability that much of the world would like to be rid of. By incorporating a thorium–plutonium mixed oxide fuel (Th-MOX) into the fuel cycle, pressurized water reactors could provide a means for the United States to address both of these issues – but only if key reactor safety parameters are not affected. The feasibility of utilizing Th-MOX fuel in a pressurized water reactor is examined under steady-state, beginning of life conditions. With a three-dimensional MCNP model of a Westinghouse-type 17 × 17 PWR, many possibilities for replacing one-third of the UO2 assemblies with Th-MOX assemblies were considered. The excess reactivity, critical boron concentration, and centerline axial and radial flux profiles for several configurations and compositions of a one-third Th-MOX core were compared to a 100% UO2 core. A blanket-type arrangement of 5.5 wt% PuO2 was determined to be the best candidate for further analysis. Therefore, this configuration was compared to a 100% UO2 core using the following parameters: delayed neutron fraction (βeff), temperature coefficient, shutdown margin (SDM), and axial and radial nuclear hot channel factors (FZN and FRN). The one-third Th-MOX configuration showed an undesirable reduction in βeff from 0.00716 ± 4.60E−07 for the 100% UO2 configuration to 0.00607 ± 4.30E−07. The reduction in βeff would perhaps be ameliorated by the one-third Th-MOX configuration’s temperature coefficient of reactivity, which at −2.05 ± 0.02 pcm °F−1 is more favorable than the corresponding value of −1.42 ± 0

  17. Synthetic and Biomass Alternate Fueling in Aviation

    Science.gov (United States)

    Hendricks, Robert C.; Bushnell, Dennis M.

    2009-01-01

    Must use earth's most abundant natural resources - Biomass, Solar, Arid land (43%), Seawater (97%) with nutrients (80%) plus brackish waters and nutrients resolve environmental triangle of conflicts energy-food-freshwater and ultrafine particulate hazards. Requires Paradigm Shift - Develop and Use Solar* for energy; Biomass for aviation and hybrid-electric-compressed air mobility fueling with transition to hydrogen long term.

  18. Transition challenges for alternative fuel vehicle and transportation systems

    OpenAIRE

    Jeroen Struben; John D. Sterman

    2008-01-01

    Automakers are now developing alternatives to internal combustion engines (ICE), including hydrogen fuel cells and ICE – electric hybrids. Adoption dynamics for alternative vehicles are complex, owing to the size and importance of the auto industry and vehicle installed base. Diffusion of alternative vehicles is both enabled and constrained by powerful positive feedbacks arising from scale and scope economies, research and development, learning by doing, driver experience, word of mouth, and ...

  19. Toxicty of thorium cycle nuclides

    International Nuclear Information System (INIS)

    The purpose of this project is to investigate the biological hazards associated with uranium-thorium breeder fuels and fuel recycle process solutions. Initial studies emphasize the metabolism and long-term biological effects of inhaled 233U-232U nitrate and oxide fuel materials andof 231Pa, a major, long-lived, radioactive waste product

  20. Impact of a single generation of uranium- and thorium-fueled recycling reactors on repository loading

    International Nuclear Information System (INIS)

    Full recycling of transuranic isotopes can in theory lead to a reduction in repository radiotoxicity to reference levels in as little as ∼500 years provided reprocessing and fuel fabrication losses are limited. However, over a limited time-frame, the radiotoxicity of the 'final' core can dominate over reprocessing losses, leading to a much lower reduction in radiotoxicity compared to that achievable at equilibrium. In this paper, the change in repository radio-toxicity for a single generation of U- or Th-fuelled 'recycling' reactors is evaluated using the UK fuel cycle scenario code ORION. Use of a single pass of U-Pu or Th-Pu mixed-oxide (MOX) fuel in a conventional PWR is also considered in isolation, and in combination with a subsequent multi-recycle reactor. Sodium-cooled fast reactor (SFR) scenarios are compared to Th-based transmutation in reduced-moderation BWRs (RBWRs). For a single generation of SFRs, use of Th fuel results in generally lower radiotoxicity than U fuel until ∼45,000 years. However, the radiotoxicity at discharge is very similar, and for limited recycling the increase in radiotoxicity beyond 45,000 years results in a slower decay to the reference level. The relatively low power density and incineration rate of the RBWR significantly limits its effectiveness for actinide transmutation for a single generation of RBWRs, and hence a long-term political commitment to a closed fuel cycle would be necessary to make them worthwhile. The advantage of recycling MAs is relatively limited in the short term. In particular, recycling Pa does not significantly affect the radiotoxicity, which weakens the argument for recycling it given the technical difficulties involved. (authors)

  1. Self-Sustaining Thorium Boiling Water Reactors

    OpenAIRE

    Ehud Greenspan; Jasmina Vujic; Francesco Ganda; Arias, Francisco J.

    2012-01-01

    A thorium-fueled water-cooled reactor core design approach that features a radially uniform composition of fuel rods in stationary fuel assembly and is fuel-self-sustaining is described. This core design concept is similar to the Reduced moderation Boiling Water Reactor (RBWR) proposed by Hitachi to fit within an ABWR pressure vessel, with the following exceptions: use of thorium instead of depleted uranium for the fertile fuel; elimination of the internal blanket; and elimination of absorber...

  2. Model for the behaviour of thorium and uranium fuels at pelletization; Modelo para o comportamento de microesferas combustiveis de torio e uranio na peletizacao

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira Neto, Ricardo Alberto

    2000-11-15

    In this work, a model for the behaviour of thorium-uranium-mixed oxide microspheres in the pelletizing process is presented. This model was developed in a program whose objective was to demonstrate the viability of producing fissile material through the utilization of thorium in pressurized water reactors. This is important because it allows the saving of the strategic uranium reserves, and makes it possible the nuclear utilization of the large brazilian thorium reserves. The objective was to develop a model for optimizing physical properties of the microspheres, such as density, fracture strength and specific surface, so as to produce fuel pellets with microstructure, density, open porosity and impurity content, in accordance with the fuel specification. And, therefore, to adjust the sol-gel processing parameters in order to obtain these properties, and produce pellets with an optimized microstructure, adequate to a stable behaviour under irradiation. The model made it clear that to achieve this objective, it is necessary to produce microspheres with density and specific surface as small as possible. By changing the sol-gel processing parameters, microspheres with the desired properties were produced, and the model was experimentally verified by manufacturing fuel pellets with optimized microstructures, density, open porosity and impurity content, meeting the specifications for this new nuclear fuel for pressurized water reactors. Furthermore it was possible to obtain mathematical expressions that enables to calculate from the microspheres properties and the utilized compaction pressure, the sinter density that will be obtained in the sintered pellet and the necessary compaction pressure to reach the sintered density specified for the fuel. (author)

  3. Combustion of solid alternative fuels in the cement kiln burner

    DEFF Research Database (Denmark)

    Nørskov, Linda Kaare

    In the cement industry there is an increasing environmental and financial motivation for substituting conventional fossil fuels with alternative fuels, being biomass or waste derived fuels. However, the introduction of alternative fuels may influence emissions, cement product quality, process...... conditions relevant to suspension fired combustion. An experimental combustion reactor for simulating suspension fired combustion of large, single particles is established and experiments are performed to investigate conversion pathways, ignition, devolatilisation, and char oxidation times of pine wood, and.......e. grinding and drying, is insufficient to ensure the dried sewage sludge to be converted within the available time in suspension, however a partial particle downsizing without drying can be allowed for refuse derived fuel firing. By increasing the entrainment rate of secondary air, the primary air percentage...

  4. Preliminary evaluation of alternate-fueled gas cooled fast reactors

    International Nuclear Information System (INIS)

    A preliminary evaluation of various alternative fuel cycles for the Gas-Cooled Fast Reactor (GCFR) is presented. Both homogeneous and heterogeneous oxide-fueled GCFRs are considered. The scenario considered is the energy center/dispersed reactor concept in which proliferation-resistant denatured reactors are coupled to 233U production reactors operating in secure energy centers. Individual reactor performance characteristics and symbiotic system parameters are summarized for several possible alternative fuel concepts. Comparisons are made between the classical homogeneous GCFR and the advanced heterogeneous concept on the basis of breeding ratio, doubling time, and net fissile gain. In addition, comparisons are made between a three-dimensional reactor model and the R-Z heterogeneous configuration utilized for the depletion and fuel management calculations. Lastly, thirty-year mass balance data are given for the various GCFR fuel cycles studied

  5. Exploring Alternative Fuels in Middle Schools

    Science.gov (United States)

    Donley, John F.; Stewardson, Gary A.

    2010-01-01

    Alternative energy sources have become increasingly important as the production of domestic oil has declined and dependence on foreign oil has increased. Historically, there have been four time periods during which the United States was in fact crippled by oil shortages. These time periods include: (1) the early 1900s; (2) World War II; (3) the…

  6. The causes and effects of the Alternative Motor Fuels Act

    Science.gov (United States)

    Liu, Yimin

    The corporate average fuel economy (CAFE) standard is the major policy tool to improve the fleet average miles per gallon of automobile manufacturers in the U.S. The Alternative Motor Fuels Act (AMFA) provides special treatment in calculating the fuel economy of alternative fuel vehicles to give manufacturers CAFE incentives to produce more alternative fuel vehicles. AMFA has as its goals an increase in the production of alternative fuel vehicles and a decrease in gasoline consumption and greenhouse gas emissions. This dissertation examines theoretically the effects of the program set up under AMFA. It finds that, under some conditions, this program may actually increase gasoline consumption and greenhouse gas emissions. The dissertation also uses hedonic techniques to examine whether the Alternative Motor Fuels Act (AMFA) has a significant effect on the implicit price of fuel economy and whether the marginal value of vehicle fuel efficiency changes over time. It estimates the change of implicit price in miles per gallon after the production of alternative fuel vehicles (AFVs). Results indicate that every year consumers may evaluate vehicle fuel economy differently, and that since AFVs came to the market, the marginal value of fuel economy from specific companies producing AFVs has decreased. This finding suggests that since the AMFA provides extra Corporate Average Fuel Economy (CAFE) credit for those automakers producing AFVs, the automakers can take advantage of the incentive to produce more profitable conventional vehicles and meet CAFE standards without improving the fleet fuel economy. In this way, manufacturers who produce AFVs are willing to offer a lower price for the fuel economy under the AMFA. Additionally, this paper suggests that the flexible fuel vehicles (FFVs) on the market are not significantly more expensive than comparable conventional vehicles, even if FFVs are also able to run on an alternative fuel and may cost more than conventional vehicles

  7. Possible types of breeders with thorium cycle

    International Nuclear Information System (INIS)

    Neutronics calculations of simplified homogeneous reactor models show the possibility that metal-fueled LMFBRs and coated particle fueled gas cooled reactors achieve reactor doubling times of around 10 years with the thorium cycle. Three concepts of gas-cooled thorium cycle breeders are discused. (Author)

  8. Possible types of breeders with thorium cycle

    International Nuclear Information System (INIS)

    Neutronics calculations of simplified homogeneous reactor models show the possibility that metal-fueled LMFBRs and coated particle fueled gas cooled reactors achieve doubling times of around 10 years with the thorium cycle. Three concepts of gas-cooled thorium cycle breeders are discussed. (Author)

  9. Life-cycle analysis of alternative aviation fuels in GREET

    Energy Technology Data Exchange (ETDEWEB)

    Elgowainy, A.; Han, J.; Wang, M.; Carter, N.; Stratton, R.; Hileman, J.; Malwitz, A.; Balasubramanian, S. (Energy Systems)

    2012-07-23

    The Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model, developed at Argonne National Laboratory, has been expanded to include well-to-wake (WTWa) analysis of aviation fuels and aircraft. This report documents the key WTWa stages and assumptions for fuels that represent alternatives to petroleum jet fuel. The aviation module in GREET consists of three spreadsheets that present detailed characterizations of well-to-pump and pump-to-wake parameters and WTWa results. By using the expanded GREET version (GREET1{_}2011), we estimate WTWa results for energy use (total, fossil, and petroleum energy) and greenhouse gas (GHG) emissions (carbon dioxide, methane, and nitrous oxide) for (1) each unit of energy (lower heating value) consumed by the aircraft or (2) each unit of distance traveled/ payload carried by the aircraft. The fuel pathways considered in this analysis include petroleum-based jet fuel from conventional and unconventional sources (i.e., oil sands); Fisher-Tropsch (FT) jet fuel from natural gas, coal, and biomass; bio-jet fuel from fast pyrolysis of cellulosic biomass; and bio-jet fuel from vegetable and algal oils, which falls under the American Society for Testing and Materials category of hydroprocessed esters and fatty acids. For aircraft operation, we considered six passenger aircraft classes and four freight aircraft classes in this analysis. Our analysis revealed that, depending on the feedstock source, the fuel conversion technology, and the allocation or displacement credit methodology applied to co-products, alternative bio-jet fuel pathways have the potential to reduce life-cycle GHG emissions by 55-85 percent compared with conventional (petroleum-based) jet fuel. Although producing FT jet fuel from fossil feedstock sources - such as natural gas and coal - could greatly reduce dependence on crude oil, production from such sources (especially coal) produces greater WTWa GHG emissions compared with petroleum jet

  10. Life-Cycle Analysis of Alternative Aviation Fuels in GREET

    Energy Technology Data Exchange (ETDEWEB)

    Elgowainy, A. [Argonne National Lab. (ANL), Argonne, IL (United States); Han, J. [Argonne National Lab. (ANL), Argonne, IL (United States); Wang, M. [Argonne National Lab. (ANL), Argonne, IL (United States); Carter, N. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Stratton, R. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Hileman, J. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Malwitz, A. [Volpe National Transportation Systems Center, Cambridge, MA (United States); Balasubramanian, S. [Volpe National Transportation Systems Center, Cambridge, MA (United States)

    2012-06-01

    The Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model, developed at Argonne National Laboratory, has been expanded to include well-to-wake (WTWa) analysis of aviation fuels and aircraft. This report documents the key WTWa stages and assumptions for fuels that represent alternatives to petroleum jet fuel. The aviation module in GREET consists of three spreadsheets that present detailed characterizations of well-to-pump and pump-to-wake parameters and WTWa results. By using the expanded GREET version (GREET1_2011), we estimate WTWa results for energy use (total, fossil, and petroleum energy) and greenhouse gas (GHG) emissions (carbon dioxide, methane, and nitrous oxide) for (1) each unit of energy (lower heating value) consumed by the aircraft or(2) each unit of distance traveled/ payload carried by the aircraft. The fuel pathways considered in this analysis include petroleum-based jet fuel from conventional and unconventional sources (i.e., oil sands); Fisher-Tropsch (FT) jet fuel from natural gas, coal, and biomass; bio-jet fuel from fast pyrolysis of cellulosic biomass; and bio-jet fuel from vegetable and algal oils, which falls under the American Society for Testing and Materials category of hydroprocessed esters and fatty acids. For aircraft operation, we considered six passenger aircraft classes and four freight aircraft classes in this analysis. Our analysis revealed that, depending on the feedstock source, the fuel conversion technology, and the allocation or displacement credit methodology applied to co-products, alternative bio-jet fuel pathways have the potential to reduce life-cycle GHG emissions by 55–85 percent compared with conventional (petroleum-based) jet fuel. Although producing FT jet fuel from fossil feedstock sources — such as natural gas and coal — could greatly reduce dependence on crude oil, production from such sources (especially coal) produces greater WTWa GHG emissions compared with petroleum jet

  11. Alcohol-fueled vehicles: An alternative fuels vehicle, emissions, and refueling infrastructure technology assessment

    Energy Technology Data Exchange (ETDEWEB)

    McCoy, G.A.; Kerstetter, J.; Lyons, J.K. [and others

    1993-06-01

    Interest in alternative motor vehicle fuels has grown tremendously over the last few years. The 1990 Clean Air Act Amendments, the National Energy Policy Act of 1992 and the California Clean Air Act are primarily responsible for this resurgence and have spurred both the motor fuels and vehicle manufacturing industries into action. For the first time, all three U.S. auto manufacturers are offering alternative fuel vehicles to the motoring public. At the same time, a small but growing alternative fuels refueling infrastructure is beginning to develop across the country. Although the recent growth in alternative motor fuels use is impressive, their market niche is still being defined. Environmental regulations, a key driver behind alternative fuel use, is forcing both car makers and the petroleum industry to clean up their products. As a result, alternative fuels no longer have a lock on the clean air market and will have to compete with conventional vehicles in meeting stringent future vehicle emission standards. The development of cleaner burning gasoline powered vehicles has signaled a shift in the marketing of alternative fuels. While they will continue to play a major part in the clean vehicle market, alternative fuels are increasingly recognized as a means to reduce oil imports. This new role is clearly defined in the National Energy Policy Act of 1992. The Act identifies alternative fuels as a key strategy for reducing imports of foreign oil and mandates their use for federal and state fleets, while reserving the right to require private and municipal fleet use as well.

  12. Economic and ecological evaluation of alternative fuels

    International Nuclear Information System (INIS)

    Under contract with OEMV-AG, a comparative evaluation of biogenic fuels (ethanol, butanol, vegetable oil and methylester of fatty acids ) was carried out from technicoeconomic, agricultural and ecological points of view with special regard to the Austrian conditions of production. Investigations were made for the raw materials starch (corn, wheat, barley, peas and beans), sugar (sugar beet and sweet sorghum) and vegetable oil (rape seed and sunflower). In accordance with the customer, cellulose was excluded from the present investigation. Data for the economic analyses were deduced from the statistics of the financial year 1989/90. (Authors)

  13. Alternate Fuel Cell Membranes for Energy Independence

    Energy Technology Data Exchange (ETDEWEB)

    Storey, Robson, F.; Mauritz, Kenneth, A.; Patton, Derek, L.; Savin, Daniel, A.

    2012-12-18

    The overall objective of this project was the development and evaluation of novel hydrocarbon fuel cell (FC) membranes that possess high temperature performance and long term chemical/mechanical durability in proton exchange membrane (PEM) fuel cells (FC). The major research theme was synthesis of aromatic hydrocarbon polymers of the poly(arylene ether sulfone) (PAES) type containing sulfonic acid groups tethered to the backbone via perfluorinated alkylene linkages and in some cases also directly attached to the phenylene groups along the backbone. Other research themes were the use of nitrogen-based heterocyclics instead of acid groups for proton conduction, which provides high temperature, low relative humidity membranes with high mechanical/thermal/chemical stability and pendant moieties that exhibit high proton conductivities in the absence of water, and synthesis of block copolymers consisting of a proton conducting block coupled to poly(perfluorinated propylene oxide) (PFPO) blocks. Accomplishments of the project were as follows: 1) establishment of a vertically integrated program of synthesis, characterization, and evaluation of FC membranes, 2) establishment of benchmark membrane performance data based on Nafion for comparison to experimental membrane performance, 3) development of a new perfluoroalkyl sulfonate monomer, N,N-diisopropylethylammonium 2,2-bis(p-hydroxyphenyl) pentafluoropropanesulfonate (HPPS), 4) synthesis of random and block copolymer membranes from HPPS, 5) synthesis of block copolymer membranes containing high-acid-concentration hydrophilic blocks consisting of HPPS and 3,3'-disulfonate-4,4'-dichlorodiphenylsulfone (sDCDPS), 6) development of synthetic routes to aromatic polymer backbones containing pendent 1H-1,2,3-triazole moieties, 7) development of coupling strategies to create phase-separated block copolymers between hydrophilic sulfonated prepolymers and commodity polymers such as PFPO, 8) establishment of basic

  14. Dimethoxymethane and trimethoxymethane as alternative fuels for fuel cells

    Science.gov (United States)

    Chetty, Raghuram; Scott, Keith

    The electrooxidation of dimethoxymethane (DMM) and trimethoxymethane (TMM) was studied at different platinum-based electrocatalysts deposited onto a titanium mesh substrate by thermal decomposition of chloride precursors. Half-cell tests showed an increase in oxidation current for the methoxy fuels at the platinum electrode with the alloying of ruthenium and tin. Increase in reaction temperature and reactant concentration showed an increase in current density for the mesh-based anodes similar to carbon-supported catalysts. Single fuel cell tests, employing the titanium mesh anode with PtRu and PtSn catalysts showed maximum power densities up to 31 mW cm -2 and 48 mW cm -2 for 1.0 mol dm -3 aqueous solutions of DMM and TMM, respectively at 60 °C using oxygen.

  15. EPAct Alternative Fuel Transportation Program: State and Alternative Fuel Provider Fleet Compliance Annual Report; Fleet Compliance Results for MY 2013/FY 2014

    Energy Technology Data Exchange (ETDEWEB)

    2015-09-01

    Compliance rates for covered state government and alternative fuel provider fleets under the Alternative Fuel Transportation Program (pursuant to the Energy Policy Act or EPAct) are reported for MY 2013/FY 2014 in this publication.

  16. Demonstrating and evaluating heavy-duty alternative fuel operations

    Energy Technology Data Exchange (ETDEWEB)

    Peerenboom, W. [Trucking Research Inst., Alexandria, VA (United States)

    1998-02-01

    The principal objectives of this project was to understand the effects of using an alternative fuel on a truck operating fleet through actual operation of trucks. Information to be gathered was expected to be anecdotal, as opposed to statistically viable, because the Trucking Research institute (TRI) recognized that projects could not attract enough trucks to produce statistically credible volumes of data. TRI was to collect operational data, and provide them to NREL, who would enter the data into the alternative fuels database being constructed for heavy-duty trucks at the time. NREL would also perform data analysis, with the understanding that the demonstrations were generally pre-production model engines and vehicles. Other objectives included providing information to the trucking industry on the availability of alternative fuels, developing the alternative fuels marketplace, and providing information on experience with alternative fuels. In addition to providing information to the trucking industry, an objective was for TRI to inform NREL and DOE about the industry, and give feedback on the response of the industry to developments in alternative fuels in trucking. At the outset, only small numbers of vehicles participated in most of the projects. Therefore, they had to be considered demonstrations of feasibility, rather than data gathering tests from which statistically significant conclusions might be drawn. Consequently, data gathered were expected to be useful for making estimates and obtaining valuable practical lessons. Project data and lessons learned are the subjects of separate project reports. This report concerns itself with the work of TRI in meeting the overall objectives of the TRI-NREL partnership.

  17. Burnup analysis of the VVER-1000 reactor using thorium-based fuel

    Energy Technology Data Exchange (ETDEWEB)

    Korkmaz, Mehmet E.; Agar, Osman; Bueyueker, Eylem [Karamanoglu Mehmetbey Univ., Karaman (Turkey). Faculty of Kamil Ozdag Science

    2014-12-15

    This paper aims to investigate {sup 232}Th/{sup 233}U fuel cycles in a VVER-1000 reactor through calculation by computer. The 3D core geometry of VVER-1000 system was designed using the Serpent Monte Carlo 1.1.19 Code. The Serpent Code using parallel programming interface (Message Passing Interface-MPI), was run on a workstation with 12-core and 48 GB RAM. {sup 232}Th/{sup 235}U/{sup 238}U oxide mixture was considered as fuel in the core, when the mass fraction of {sup 232}Th was increased as 0.05-0.1-0.2-0.3-0.4 respectively, the mass fraction of {sup 238}U equally was decreased. In the system, the calculations were made for 3 000 MW thermal power. For the burnup analyses, the core is assumed to deplete from initial fresh core up to a burnup of 16 MWd/kgU without refuelling considerations. In the burnup calculations, a burnup interval of 360 effective full power days (EFPDs) was defined. According to burnup, the mass changes of the {sup 232}Th, {sup 233}U, {sup 238}U, {sup 237}Np, {sup 239}Pu, {sup 241}Am and {sup 244}Cm were evaluated, and also flux and criticality of the system were calculated in dependence of the burnup rate.

  18. Burnup analysis of the VVER-1000 reactor using thorium-based fuel

    International Nuclear Information System (INIS)

    This paper aims to investigate 232Th/233U fuel cycles in a VVER-1000 reactor through calculation by computer. The 3D core geometry of VVER-1000 system was designed using the Serpent Monte Carlo 1.1.19 Code. The Serpent Code using parallel programming interface (Message Passing Interface-MPI), was run on a workstation with 12-core and 48 GB RAM. 232Th/235U/238U oxide mixture was considered as fuel in the core, when the mass fraction of 232Th was increased as 0.05-0.1-0.2-0.3-0.4 respectively, the mass fraction of 238U equally was decreased. In the system, the calculations were made for 3 000 MW thermal power. For the burnup analyses, the core is assumed to deplete from initial fresh core up to a burnup of 16 MWd/kgU without refuelling considerations. In the burnup calculations, a burnup interval of 360 effective full power days (EFPDs) was defined. According to burnup, the mass changes of the 232Th, 233U, 238U, 237Np, 239Pu, 241Am and 244Cm were evaluated, and also flux and criticality of the system were calculated in dependence of the burnup rate.

  19. Commercial and economic comparison of traditional and alternative fuels

    OpenAIRE

    Dvořáková, Monika

    2010-01-01

    Negative predictions about oil stocks combined with the instability in the Middle East encourage development of alternative fuels, which would reduce dependence of the world's economies on oil. The oil and petroleum derivatives are the main dependencies for vehicular traffic, which contributes to the greenhouse gas emissions by a large part. It is therefore necessary to focus on trying to reduce the fuel consumption of cars used for personal transportation. One way to achieve this goal is, fo...

  20. An update in the 'development of alternate liquid fuels'

    Science.gov (United States)

    Rose, M. J.

    The Brookhaven National Laboratory has formulated a series of Alternate Liquid Fuels (AIF), compounded from combustible fluids such as alcohols, mineral oils and solvents, found in the waste streams of the cosmetic, petrochemical, electronics and other industries. These fuels are now being processed by a pilot plant with a productive capacity of 40,000 gallons in 8 hours, at direct costs ranging from $0.26 to $0.29 a gallon depending on selected feedstocks and blend ratios

  1. A molecular dynamics study of the thermal properties of thorium oxide

    OpenAIRE

    Martin, Paul; David J. Cooke; Cywinski, R.

    2012-01-01

    There is growing interest in the exploitation of the thorium nuclear fuel cycle as an alternative to that of uranium. As part of a wider study of the suitability of thorium dioxide (thoria) as a nuclear fuel, we have used molecular dynamics to investigate the thermal expansion, oxygen diffusion, and heat capacity of pure thoria and uranium doped (1-10%) thoria between 1500K and 3600 K. Our results indicate that the thermal performance of the thoria matrix, even when doped with 10%U, is compar...

  2. Development of alternative materials for BWR fuel springs

    International Nuclear Information System (INIS)

    Major sources of radioactivity introduced into reactor water of BWR were estimated fuel crud and in-core materials (especially, fuel springs). Fuel springs are used for fixation of fuel cladding tubes with spacer grid. Those are small parts (total length is only within 25 mm) and so many numbers are loaded simultaneously and then total surfaces area are calculated up to about 200 m2. Fuel springs are located under high radiation field and high oxidative environment. Conventional fuel spring is made of alloy-X750 which is one of nickel-based alloy and is reported to show relatively higher corrosion release rate. 58Co and 60Co will be released directly into reactor water from intensely radio-activated fuel springs surface and increase radioactivity concentrations in primary coolant. Corrosion release control from fuel springs is an important technical item and a development of alternative material instead of alloy-X750 for fuel spring is a key subject to achieve ultra low man-rem exposure BWR plant. In present work, alloy-X718 which started usage for PWR fuel springs and stainless steel type 316L which has many mechanical property data are picked up for alternative materials and compared their corrosion behaviors with conventional material. Corrosion experiment was conducted under vapor-water two phases flow which is simulated fuel cladding surface boiling condition. After exposure, corrosion film formed under corrosion test was analyzed in detail and corrosion film amount and corrosion release amount are estimated among three materials. (authors)

  3. Alternative Liquid Fuels Simulation Model (AltSim).

    Energy Technology Data Exchange (ETDEWEB)

    Baker, Arnold Barry; Williams, Ryan (Hobart and William Smith Colleges, Geneva, NY); Drennen, Thomas E.; Klotz, Richard (Hobart and William Smith Colleges, Geneva, NY)

    2007-10-01

    The Alternative Liquid Fuels Simulation Model (AltSim) is a high-level dynamic simulation model which calculates and compares the production costs, carbon dioxide emissions, and energy balances of several alternative liquid transportation fuels. These fuels include: corn ethanol, cellulosic ethanol, biodiesel, and diesels derived from natural gas (gas to liquid, or GTL) and coal (coal to liquid, or CTL). AltSim allows for comprehensive sensitivity analyses on capital costs, operation and maintenance costs, renewable and fossil fuel feedstock costs, feedstock conversion efficiency, financial assumptions, tax credits, CO{sub 2} taxes, and plant capacity factor. This paper summarizes the preliminary results from the model. For the base cases, CTL and cellulosic ethanol are the least cost fuel options, at $1.60 and $1.71 per gallon, respectively. Base case assumptions do not include tax or other credits. This compares to a $2.35/gallon production cost of gasoline at September, 2007 crude oil prices ($80.57/barrel). On an energy content basis, the CTL is the low cost alternative, at $12.90/MMBtu, compared to $22.47/MMBtu for cellulosic ethanol. In terms of carbon dioxide emissions, a typical vehicle fueled with cellulosic ethanol will release 0.48 tons CO{sub 2} per year, compared to 13.23 tons per year for coal to liquid.

  4. TAFV Alternative Fuels and Vehicles Choice Model Documentation; TOPICAL

    International Nuclear Information System (INIS)

    A model for predicting choice of alternative fuel and among alternative vehicle technologies for light-duty motor vehicles is derived. The nested multinomial logit (NML) mathematical framework is used. Calibration of the model is based on information in the existing literature and deduction based on assuming a small number of key parameters, such as the value of time and discount rates. A spreadsheet model has been developed for calibration and preliminary testing of the model

  5. TAFV Alternative Fuels and Vehicles Choice Model Documentation

    Energy Technology Data Exchange (ETDEWEB)

    Greene, D.L.

    2001-07-27

    A model for predicting choice of alternative fuel and among alternative vehicle technologies for light-duty motor vehicles is derived. The nested multinomial logit (NML) mathematical framework is used. Calibration of the model is based on information in the existing literature and deduction based on assuming a small number of key parameters, such as the value of time and discount rates. A spreadsheet model has been developed for calibration and preliminary testing of the model.

  6. Proceedings of the international thorium energy conference: gateway to thorium energy

    International Nuclear Information System (INIS)

    Fuels cycles based on thorium, due to a number of favourable neutronics and material characteristics, could help address the issues of long-term sustainability of fuel resources and also the proliferation concerns associated with uranium based fuel cycles. In the case of India, due to our modest reserves of uranium and large reserves of thorium, efficient utilisation of thorium is an essential requisite and indeed the cornerstone of the Indian nuclear programme. This conference address the issues concerning thorium and its utilization in nuclear programme. Papers relevant to INIS are indexed separately

  7. Alternative Methods for Treatment of TRISO Fuels

    International Nuclear Information System (INIS)

    The current treatment technologies of spent TRISO fuel have been review. The proposed innovative technologies such as thermal shock breaching and EMS-CC processes were found to be promising. A schematic flow sheet has been constructed by using thermal shock, EMS-CC process and separation of breached fines. The heating and fracture behavior of SiC powder by RF heating was investigated. Hoop stress was calculated for breaching of coating layers by inter fission gas pressure at elevated temperature. Electrolytic molten salt cell was installed in glove box and preliminary test was performed. EMS-CC reaction was realized by using glassy carbon and CVD SiC. The morphology of the sample was observed after EMS-CC test. Cyclic voltammogram was constructed by using SiC in order to check the effect of magnesium as a reductant. Investigation of fracture behavior of TRISO coating layers by using thermal shock : 1500 .deg. C of temperature gradient was applied. Macro, microstructure and crystal structure were investigated by using XRD and SEM. Vicker hardness was measured before and after experiment. Innovative gas-solid reaction method beside RF heating and EMS-CC was proposed. This process was also evaluated as a promising to decrease secondary waste. Construction of cyclone separator and optimization : ZrO2(kernel), SiC and graphite powders as surrogate of TRISO were used for the process optimization of fluidization separator equipped with cyclone. The optimum condition was found to be 1.5cm/s of fluidization velocity and 99.9% of separation efficiency was achieved. Literature survey of FP recovery : Recovery technologies of fission products such as I, Kr/Xe, 14C and tritium which are released during the breaching process were surveyed, and its flow sheet was constructed

  8. State of the Art on Alternative Fuels in Aviation. SWAFEA. Sustainable Way for Alternative Fuels and Energy in Aviation.

    OpenAIRE

    Blakey, S.; Novelli, P.; Costes, P.; Bringtown, S.; Christensen, D.; Sakintuna, B.; Peineke, C.; Jongschaap, R. E. E.; Conijn, J.G.; Rutgers, B.; Valot, L.; E Joubert; Perelgritz, J.F.; Filogonio, A.; Roetger, T.

    2010-01-01

    Currently, the aviation sector uses petroleum derived liquid fuels as the energy carrier of choice for flight. In light the present environmental, economical and political concerns as to the sustainability of this energy source, the question of which alternatives the aviation sector should pursue in the future has emerged. Among these concerns, the environmental impact of fossil fuel use on global warming and air quality is of major importance, while the impact of volatile oil prices and the ...

  9. Long-term alternatives for nuclear fuel cycles

    International Nuclear Information System (INIS)

    Several technical alternatives have been proposed to the nuclear spent fuel management but the practical experience on any of these is small or totally lacking. Since the management method is also connected with the composition of fresh fuel, the comparison of the alternatives must include the whole fuel cycle of a nuclear power plant. In the planning of the nuclear fuel cycle over a time range of several decades a consideration must be given, in addition, to the potential of the new reactor types with increased efficiency of uranium utilization. For analyses and mutual comparisons of the fuel cycle alternatives a number of computer models have been designed and implemented at the Technical Research Centre of Finland. Given the estimated boundary conditions the models can be used to study the impact of different goals and requirements on the fuel cycle decisions. Further, they facilitate cost predictions and display information on the role of the intrinsic uncertainties in the decision-making. The conclusions of the study are tied to the questions of price and availability of uranium. Hence, for instance, the benefits from the reprocessing of spent fuel might prove to be small when compared to the costs required, especially as the current reprocessing contracts do not allow the custemer to dismiss the duty of building the final disposal facilities for high level radioactive waste. For a few decades the final decisions can be postponed by extending the interim storage period. Farther in the future the decisions in the nuclear fuel cycle arrangements will more link to the introduction of the fast breeder reactors. (author)

  10. Market brief : the alternative fuels bus market in India

    International Nuclear Information System (INIS)

    In 2003, alternative fuel bus technologies in India were valued at approximately $1.5 billion. There are an estimated 600,000 buses in India, of which 21 per cent are owned by public transit. Bus production is currently 33,000 per year and increasing at 4 per cent annually. The main alternative fuel bus technologies include fuel cells, compressed natural gas (CNG) and liquefied petroleum gas (LPG). Since urban centres in India are among the most polluted in the world, demand for these technologies is strong. India is ranked fifth in the world in terms of vehicles converted to natural gas. In 2003, New Delhi switched from diesel to CNG fuel for buses but has faced challenges because there is no well-developed underground distribution system and refilling times are long due to weak pressure at fueling stations. India's new $28 million fuel cell bus development project aims to place 8 fuel cell powered buses with the Delhi Transport Corporation. This market brief describes the potential for Canadian suppliers to enter into joint ventures to establish local production facilities and transfer technology expertise. It describes the key factors shaping market growth with particular reference to sector reform, and opportunities with actual and planned projects. The competitive environment was also discussed with reference to local capabilities, international competition, Canadian position, and a competitive advantage through Canadian government policies and initiatives. A section of the report on public-sector customers listed the companies that buy alternative fuel buses in India. Considerations for market-entry in India were also outlined

  11. Advanced Proliferation Resistant, Lower Cost, Uranium-Thorium Dioxide Fuels for Light Water Reactors (Progress report for work through June 2002, 12th quarterly report)

    International Nuclear Information System (INIS)

    The overall objective of this NERI project is to evaluate the potential advantages and disadvantages of an optimized thorium-uranium dioxide (ThO2/UO2) fuel design for light water reactors (LWRs). The project is led by the Idaho National Engineering and Environmental Laboratory (INEEL), with the collaboration of three universities, the University of Florida, Massachusetts Institute of Technology (MIT), and Purdue University; Argonne National Laboratory; and all of the Pressurized Water Reactor (PWR) fuel vendors in the United States (Framatome, Siemens, and Westinghouse). In addition, a number of researchers at the Korean Atomic Energy Research Institute and Professor Kwangheon Park at Kyunghee University are active collaborators with Korean Ministry of Science and Technology funding. The project has been organized into five tasks: Task 1 consists of fuel cycle neutronics and economics analysis to determine the economic viability of various ThO2/UO2 fuel designs in PWRs; Task 2 will determine whether or not ThO2/UO2 fuel can be manufactured economically; Task 3 will evaluate the behavior of ThO2/UO2 fuel during normal, off-normal, and accident conditions and compare the results with the results of previous UO2 fuel evaluations and U.S. Nuclear Regulatory Commission (NRC) licensing standards; Task 4 will determine the long-term stability of ThO2/UO2 high-level waste; and Task 5 consists of the Korean work on core design, fuel performance analysis, and xenon diffusivity measurements

  12. Examination of physical properties of fuels and mixtures with alternative fuels

    Science.gov (United States)

    Lown, Anne Lauren

    ABSTRACT. EXAMINATION OF PHYSICAL PROPERTIES OF FUELS AND MIXTURES WITH ALTERNATIVE FUELS. By. Anne Lauren Lown. The diversity of alternative fuels is increasing due to new second generation biofuels. By modeling alternative fuels and fuel mixtures, types of fuels can be selected based on their properties, without producing and testing large batches. A number of potential alternative fuels have been tested and modeled to determine their impact when blended with traditional diesel and jet fuels. The properties evaluated include cloud point and pour point temperature, cetane number, distillation curve, and speed of sound. This work represents a novel approach to evaluating the properties of alternative fuels and their mixtures with petroleum fuels. Low temperature properties were evaluated for twelve potential biofuel compounds in mixtures with three diesel fuels and one jet fuel. Functional groups tested included diesters, esters, ketones, and ethers, and alkanes were used for comparison. Alkanes, ethers, esters, and ketones with a low melting point temperature were found to decrease the fuel cloud point temperature. Diesters added to fuels display an upper critical solution temperature, and multiple methods were used to confirm the presence of liquid-liquid immiscibility. These behaviors are independent of chain length and branching, as long as the melting point temperature of the additive is not significantly higher than the cloud point temperature of the fuel. Physical properties were estimated for several potential fuel additive molecules using group contribution methods. Quantum chemical calculations were used for ideal gas heat capacities. Fuel surrogates for three petroleum based fuels and six alternative fuels were developed. The cloud point temperature, distillation curve, cetane number, and average molecular weight for different fuel surrogates were simultaneously represented. The proposed surrogates use the experimental mass fractions of paraffins, and

  13. Primer on Motor Fuel Excise Taxes and the Role of Alternative Fuels and Energy Efficient Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, Alex [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2015-08-26

    Motor fuel taxes were established to finance our nation’s transportation infrastructure, yet evolving economic, political, and technological influences are constraining this ability. At the federal level, the Highway Trust Fund (HTF), which is primarily funded by motor fuel taxes, has become increasingly dependent on general fund contributions and short-term reauthorizations to prevent insolvency. As a result, there are discussions at both the federal and state levels in which stakeholders are examining the future of motor fuel excise taxes as well as the role of electric and alternative fuel vehicles in that future. On July 1, 2015, six states increased their motor fuel tax rates.

  14. Thorium research and development in Turkey

    International Nuclear Information System (INIS)

    Turkey has a great potential regarding thorium resources. Thorium exploration activities have been done in the past mainly by state organizations for determining the thorium resources in Turkey. Thorium occurs as complex mineral together with barite, fluorite and rare earth elements (REE). The increase in global demand for REE creates the opportunity for REE production which will also produce thorium as a by-product. The development of nuclear energy program in Turkey provides the stimulus for research and development activities in nuclear technologies. The final declaration of the workshop emphasizes the importance of thorium reserves in Turkey and the necessity for thorium exploration and development activities in order to determine the feasibility of thorium mining and fuel cycle in Turkey. These activities should be conducted together with the development of technologies for separation of these complex minerals and purification of thorium, REE and other minerals to be utilized as commercial products. There are advanced academic research studies on thorium fuel cycle which should be supported by the industry in order to commercialize the results of these studies. Turkey should be integrated to international R and D activities on ADS which is expected to commercialize on medium term. The legislative framework should be developed in order to provide the industrial baseline for nuclear technologies independent from nuclear regulatory activities

  15. Emissions from Petrol Engine Fueled Gasoline–Ethanol–Methanol (GEM) Ternary mixture as Alternative Fuel

    OpenAIRE

    Thangavelu Saravana Kannan; Chelladorai Piraiarasi; Ani Farid Nasir

    2015-01-01

    The increasing demands of petroleum fuels due to the rapid development automotive society coupled with the environmental pollution issues have inspired the efforts on exploring alternative fuels for internal combustion engines. Bioethanol obtained from biomass and bioenergy crops has been proclaimed as one of the feasible alternative to gasoline. In this study, the effect of gasoline–ethanol–methanol (GEM) ternary blend on the emission characteristics of petrol engine was studied. Three diffe...

  16. Symbiotic energy demand and supply system based on collaboration between rare-earth and thorium utilization

    International Nuclear Information System (INIS)

    Progressive economic growth as well as prodigious consumption of energy are expected among Asian countries. Nuclear power has myriad advantages, among them particularly being its status as a low carbon technology and therefore nuclear power would make a significant contribution to curtailing CO2 emissions. However, the prospects for nuclear power are hindered by some unresolved problems: perceived adverse safety, environmental, and health effects; potential security risks stemming from proliferation; and unresolved challenges in long-term management of nuclear wastes. Thorium utilization as a nuclear fuel will serve as a cornerstone of circumventing such problems, because thorium produces less radioactive waste (i.e. less plutonium) and thus safety, which is of paramount concern, will be enhanced. The deployment of electric vehicles (EVs) as an alternative to supplant gasoline engine cars in the transportation network, will significantly contribute in the reduction of global CO2 emissions. Rare-earth materials such as neodymium and dysprosium will be essential as a new material for electric automobiles. Thorium is often obtained as a by-product of rare-earth metals, but it is still not utilized as a nuclear fuel currently due to the lack of its own fissionable isotopes and as such, it cannot be employed in the production of nuclear weapons. Recent trends of nuclear disarmament and accumulation of plutonium from uranium fuel cycle can propel the deployment of thorium. The implementation capacity of thorium nuclear power is estimated to be about 392 GWe at 2050. The utilization of thorium will both help to provide clean energy and to supply rare-earth materials for clean automobiles. In order for us to effect the commercial deployment of thorium resources, establishment of an international framework to supply resources from developing countries as well as to supply technology from developed countries is indeed imperative. Herein, the author propose 'The Bank (Thorium

  17. An alternative fuel for urban buses-biodiesel blends

    Energy Technology Data Exchange (ETDEWEB)

    Schumacher, L.G.; Weber, J.A.; Russell, M.D. [Univ. of Missouri, Columbia, MO (United States)] [and others

    1995-11-01

    Qualitative and quantitative biodiesel fueling performance and operational data have been collected from urban mass transit buses at Bi-State Development Agency in St. Louis Missouri. A total of 10 vehicles were selected for fueling; 5-6V92 TA Detroit Diesel engines have been fueled with a 20/80 biodiesel/diesel fuel blend and 5-6V92 TA Detroit Diesel control vehicles have been fueled on petroleum based low sulfur diesel fuel (LSD). The real-world impact of a biodiesel blend on maintenance, reliability, cost, fuel economy and safety compared to LSD will be presented. In addition, engine exhaust emissions data collected by the University of West Virginia Department of Energy (DOE) sponsored mobile emissions laboratory will be presented. Operational data from Bi-State Development Agency is collected by the University of Missouri and quality control procedures are performed prior to placing the data in the Alternative Fuels Data Center (AFDC). The AFDC is maintained by the National Renewable Energy Laboratory in Golden, Colorado. This effort, which enables transit operators to review a real-world comparison of biodiesel and LSD, has been funded by the National Biodiesel Board with funds provided by the United Soybean Board with national checkoff dollars and the National Renewable Energy Laboratory.

  18. FY2015 Annual Report for Alternative Fuels DISI Engine Research.

    Energy Technology Data Exchange (ETDEWEB)

    Sjöberg, Carl-Magnus G. [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

    2016-01-01

    Climate change and the need to secure energy supplies are two reasons for a growing interest in engine efficiency and alternative fuels. This project contributes to the science-base needed by industry to develop highly efficient DISI engines that also beneficially exploit the different properties of alternative fuels. Our emphasis is on lean operation, which can provide higher efficiencies than traditional non-dilute stoichiometric operation. Since lean operation can lead to issues with ignition stability, slow flame propagation and low combustion efficiency, we focus on techniques that can overcome these challenges. Specifically, fuel stratification is used to ensure ignition and completeness of combustion but has soot- and NOx- emissions challenges. For ultralean well-mixed operation, turbulent deflagration can be combined with controlled end-gas auto-ignition to render mixed-mode combustion that facilitates high combustion efficiency. However, the response of both combustion and exhaust emissions to these techniques depends on the fuel properties. Therefore, to achieve optimal fuel-economy gains, the engine combustion-control strategies must be adapted to the fuel being utilized.

  19. Annual Report FY2014 Alternative Fuels DISI Engine Research.

    Energy Technology Data Exchange (ETDEWEB)

    Sjoberg, Carl-Magnus G. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-01-01

    Due to concerns about future petroleum supply and accelerating climate change, increased engine efficiency and alternative fuels are of interest. This project contributes to the science-base needed by industry to develop highly efficient DISI engines that also beneficially exploit the different properties of alternative fuels. Lean operation is studied since it can provide higher efficiencies than traditional non-dilute stoichiometric operation. Since lean operation can lead to issues with ignition stability, slow flame propagation and low combustion efficiency, focus is on techniques that can overcome these challenges. Specifically, fuel stratification can be used to ensure ignition and completeness of combustion, but may lead to soot and NOx emissions challenges. Advanced ignition system and intake air preheating both promote ignition stability. Controlled end-gas autoignition can be used maintain high combustion efficiency for ultra-lean well-mixed conditions. However, the response of both combustion and exhaust emission to these techniques depends on the fuel properties. Therefore, to achieve optimal fuel-economy gains, the combustion-control strategies of the engine must adopt to the fuel being utilized.

  20. Societal lifecycle costs of cars with alternative fuels/engines

    International Nuclear Information System (INIS)

    Effectively addressing concerns about air pollution (especially health impacts of small-particle air pollution), climate change, and oil supply insecurity will probably require radical changes in automotive engine/fuel technologies in directions that offer both the potential for achieving near-zero emissions of air pollutants and greenhouse gases and a diversification of the transport fuel system away from its present exclusive dependence on petroleum. The basis for comparing alternative automotive engine/fuel options in evolving toward these goals in the present analysis is the 'societal lifecycle cost' of transportation, including the vehicle first cost (assuming large-scale mass production), fuel costs (assuming a fully developed fuel infrastructure), externality costs for oil supply security, and damage costs for emissions of air pollutants and greenhouse gases calculated over the full fuel cycle. Several engine/fuel options are considered--including current gasoline internal combustion engines and a variety of advanced lightweight vehicles: internal combustion engine vehicles fueled with gasoline or hydrogen; internal combustion engine/hybrid electric vehicles fueled with gasoline, compressed natural gas, Diesel, Fischer-Tropsch liquids or hydrogen; and fuel cell vehicles fueled with gasoline, methanol or hydrogen (from natural gas, coal or wind power). To account for large uncertainties inherent in the analysis (for example in environmental damage costs, in oil supply security costs and in projected mass-produced costs of future vehicles), lifecycle costs are estimated for a range of possible future conditions. Under base-case conditions, several advanced options have roughly comparable lifecycle costs that are lower than for today's conventional gasoline internal combustion engine cars, when environmental and oil supply insecurity externalities are counted--including advanced gasoline internal combustion engine cars, internal combustion engine

  1. Air quality effects of alternative fuels. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Guthrie, P.; Ligocki, M.; Looker, R.; Cohen, J.

    1997-11-01

    To support the Alternative Fuels Utilization Program, a comparison of potential air quality effects of alternative transportation fuels is being performed. This report presents the results of Phase 1 of this program, focusing on reformulated gasoline (RFG), methanol blended with 15 percent gasoline (M85), and compressed natural gas (CNG). The fuels are compared in terms of effects on simulated future concentrations of ozone and mobile source air toxics in a photochemical grid model. The fuel comparisons were carried out for the future year 2020 and assumed complete replacement of gasoline in the projected light-duty gasoline fleet by each of the candidate fuels. The model simulations were carried out for the areas surrounding Los Angeles and Baltimore/DC, and other (non-mobile) sources of atmospheric emissions were projected according to published estimates of economic and population growth, and planned emission control measures specific to each modeling domain. The future-year results are compared to a future-year run with all gasoline vehicle emissions removed. The results of the comparison indicate that the use of M85 is likely to produce similar ozone and air toxics levels as those projected from the use of RFG. Substitution of CNG is projected to produce significantly lower levels of ozone and the mobile source air toxics than those projected for RFG or M85. The relative benefits of CNG substitution are consistent in both modeling domains. The projection methodologies used for the comparison are subject to a large uncertainty, and modeled concentration distributions depend on meteorological conditions. The quantitative comparison of fuel effects is thus likely to be sensitive to alternative assumptions. The consistency of the results for two very different modeling domains, using very different base assumptions, lends credibility to the qualitative differentiation among these fuels. 32 refs., 42 figs., 47 tabs.

  2. Moving beyond alternative fuel hype to decarbonize transportation

    Science.gov (United States)

    Melton, Noel; Axsen, Jonn; Sperling, Daniel

    2016-03-01

    In the past three decades, government, industry and other stakeholders have repeatedly been swept up with the ‘fuel du jour’, claiming that a particular alternative fuel vehicle (AFV) technology can succeed in replacing conventional gasoline-powered vehicles. However, AFV technologies have experienced relatively little success, with fossil fuels still accounting for about 95% of global transport energy use. Here, using the US as a case study, we conduct a media analysis to show how society’s attention has skipped among AFV types between 1980 and 2013, including methanol, natural gas, plug-in electric, hybrid electric, hydrogen and biofuels. Although our results provide no indication as to whether hype ultimately has a net positive or negative impact on AFV innovation, we offer several recommendations that governments can follow to move past hype to support significant AFV adoption and displace fossil fuel use in the transportation sector.

  3. Power generation costs for alternate reactor fuel cycles

    International Nuclear Information System (INIS)

    The total electric generating costs at the power plant busbar are estimated for various nuclear reactor fuel cycles which may be considered for power generation in the future. The reactor systems include pressurized water reactors (PWR), heavy-water reactors (HWR), high-temperature gas cooled reactors (HTGR), liquid-metal fast breeder reactors (LMFBR), light-water pre-breeder and breeder reactors (LWPR, LWBR), and a fast mixed spectrum reactor (FMSR). Fuel cycles include once-through, uranium-only recycle, and full recycle of the uranium and plutonium in the spent fuel assemblies. The U3O8 price for economic transition from once-through LWR fuel cycles to both PWR recycle and LMFBR systems is estimated. Electric power generation costs were determined both for a reference set of unit cost parameters and for a range of uncertainty in these parameters. In addition, cost sensitivity parameters are provided so that independent estimations can be made for alternate cost assumptions

  4. Life cycle models of conventional and alternative-fueled automobiles

    Science.gov (United States)

    Maclean, Heather Louise

    This thesis reports life cycle inventories of internal combustion engine automobiles with feasible near term fuel/engine combinations. These combinations include unleaded gasoline, California Phase 2 Reformulated Gasoline, alcohol and gasoline blends (85 percent methanol or ethanol combined with 15 percent gasoline), and compressed natural gas in spark ignition direct and indirect injection engines. Additionally, I consider neat methanol and neat ethanol in spark ignition direct injection engines and diesel fuel in compression ignition direct and indirect injection engines. I investigate the potential of the above options to have a lower environmental impact than conventional gasoline-fueled automobiles, while still retaining comparable pricing and consumer benefits. More broadly, the objective is to assess whether the use of any of the alternative systems will help to lead to the goal of a more sustainable personal transportation system. The principal tool is the Economic Input-Output Life Cycle Analysis model which includes inventories of economic data, environmental discharges, and resource use. I develop a life cycle assessment framework to assemble the array of data generated by the model into three aggregate assessment parameters; economics, externalities, and vehicle attributes. The first step is to develop a set of 'comparable cars' with the alternative fuel/engine combinations, based on characteristics of a conventional 1998 gasoline-fueled Ford Taurus sedan, the baseline vehicle for the analyses. I calculate the assessment parameters assuming that these comparable cars can attain the potential thermal efficiencies estimated by experts for each fuel/engine combination. To a first approximation, there are no significant differences in the assessment parameters for the vehicle manufacture, service, fixed costs, and the end-of-life for any of the options. However, there are differences in the vehicle operation life cycle components and the state of technology

  5. Alternative Fuel Cycle Evaluation Program. Volume IV. International Fuel Service Center evaluation. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Jacobson, L D [comp.

    1979-11-01

    This Alternative Fuel Cycle Evaluation Program (AFCEP) study presents the technical, economic and social aspects of the International Fuel Service Center (IFSC) as an institutional approach to nuclear fuel cycle development and is provided in support of the Nonproliferation Alternative Systems Assessment program (NASAP). Four types of IFSCs are described and evaluated in terms of three different twenty-year nuclear growth scenarios. Capital costs for each IFSC and comparable dispersed facility costs are discussed. Finally, the possible impact of each scenario and IFSC on the environmental and socio-economic structure is examined. 14 refs., 33 figs., 15 tabs.

  6. Fuel-cycle greenhouse gas emissions impacts of alternative transportation fuels and advanced vehicle technologies

    International Nuclear Information System (INIS)

    At an international conference on global warming, held in Kyoto, Japan, in December 1997, the United States committed to reduce its greenhouse gas (GHG) emissions by 7% over its 1990 level by the year 2012. To help achieve that goal, transportation GHG emissions need to be reduced. Using Argonne's fuel-cycle model, I estimated GHG emissions reduction potentials of various near- and long-term transportation technologies. The estimated per-mile GHG emissions results show that alternative transportation fuels and advanced vehicle technologies can help significantly reduce transportation GHG emissions. Of the near-term technologies evaluated in this study, electric vehicles; hybrid electric vehicles; compression-ignition, direct-injection vehicles; and E85 flexible fuel vehicles can reduce fuel-cycle GHG emissions by more than 25%, on the fuel-cycle basis. Electric vehicles powered by electricity generated primarily from nuclear and renewable sources can reduce GHG emissions by 80%. Other alternative fuels, such as compressed natural gas and liquefied petroleum gas, offer limited, but positive, GHG emission reduction benefits. Among the long-term technologies evaluated in this study, conventional spark ignition and compression ignition engines powered by alternative fuels and gasoline- and diesel-powered advanced vehicles can reduce GHG emissions by 10% to 30%. Ethanol dedicated vehicles, electric vehicles, hybrid electric vehicles, and fuel-cell vehicles can reduce GHG emissions by over 40%. Spark ignition engines and fuel-cell vehicles powered by cellulosic ethanol and solar hydrogen (for fuel-cell vehicles only) can reduce GHG emissions by over 80%. In conclusion, both near- and long-term alternative fuels and advanced transportation technologies can play a role in reducing the United States GHG emissions

  7. Environmental consequences of uranium atmospheric releases from fuel cycle facility: II. The atmospheric deposition of uranium and thorium on plants

    International Nuclear Information System (INIS)

    Uranium and thorium isotopes were measured in cypress leaves, wheat grains and lettuce taken in the surroundings of the uranium conversion facility of Malvési (South of France). The comparison of activity levels and activity ratios (namely 238U/232Th and 230Th/232Th) in plants with those in aerosols taken at this site and plants taken far from it shows that aerosols emitted by the nuclear site (uranium releases in the atmosphere by stacks and 230Th-rich particles emitted from artificial ponds collecting radioactive waste mud) accounts for the high activities recorded in the plant samples close to the site. The atmospheric deposition process onto the plants appears to be the dominant process in plant contamination. Dry deposition velocities of airborne uranium and thorium were measured as 4.6 × 10−3 and 5.0 × 10−3 m s−1, respectively. - Highlights: • Uranium and thorium were measured in plants near the uranium conversion facility. • Activity ratios show that emissions account for the high activities recorded in the plants. • The atmospheric deposition process appears to dominate in plant contamination. • Dry deposition velocities of airborne uranium and thorium were determined

  8. Determination of alternative fuels combustion products: Phase 3 report

    Energy Technology Data Exchange (ETDEWEB)

    Whitney, K.A. [Southwest Research Inst., San Antonio, TX (United States)

    1997-12-01

    This report describes the laboratory efforts to characterize particulate and gaseous exhaust emissions from a passenger vehicle operating on alternative fuels. Tests were conducted at room temperature (nominally 72 F) and 20 F utilizing the chassis dynamometer portion of the FTP for light-duty vehicles. Fuels evaluated include Federal RFG, LPG meeting HD-5 specifications, a national average blend of CNG, E85, and M85. Exhaust particulate generated at room temperature was further characterized to determine polynuclear aromatic content, trace element content, and trace organic constituents. For all fuels except M85, the room temperature particulate emission rate from this vehicle was about 2 to 3 mg/mile. On M85, the particulate emission rate was more than 6 mg/mile. In addition, elemental analysis of particulate revealed an order of magnitude more sulfur and calcium from M85 than any other fuel. The sulfur and calcium indicate that these higher emissions might be due to engine lubricating oil in the exhaust. For RFG, particulate emissions at 20 F were more than six times higher than at room temperature. For alcohol fuels, particulate emissions at 20 F were two to three times higher than at room temperature. For CNG and LPG, particulate emissions were virtually the same at 72 F and 20 F. However, PAH emissions from CNG and LPG were higher than expected. Both gaseous fuels had larger amounts of pyrene, 1-nitropyrene, and benzo(g,h,i)perylene in their emissions than the other fuels.

  9. Part 2. Design and performance characteristics of alternative fuels and fuel cycles

    International Nuclear Information System (INIS)

    This report documents performance characteristics of a wide range of fast breeder reactor designs and fuel cycle options to provide the bases for the study of alternatives that is the primary focus of the International Nuclear Fuel Cycle Evaluation. Since breeding performance is at the center of many of the feasibility questions connected with alternative forms of breeder development, particular attention was given to a consistent comparison between various alternatives and quantitative analyses that provide physical understanding of intrinsic differences in their breeding performance

  10. Low energy neutron data relating to thorium

    International Nuclear Information System (INIS)

    As thorium fuel cycle had some elements useful for effective application of nuclear fuel resource and nonproliferation, it had been much focussed by Carter political power borne in 1976. Because of this factor, a number of experiments and research actions had been promoted to nuclear data on thorium isotopes among 10 years after then. By aging this a moment, the thorium research in Japan showed a remarkable advancement. Difficulties of the thorium experiment at a viewpoint of nuclear experiment, are high radiation dose in its handling and experiment, high background on its experiment and regulation at its use for a nuclear fuel substance. In this paper, after the special research on energy, three examples with much interests were introduced among nuclear experimental data on thorium series against the low energy neutron by using electron accelerator at the Research Reactor Institute, Kyoto University. (G.K.)

  11. Modern approach to the problem of fossil gas fuels replacement by alternative fuels

    International Nuclear Information System (INIS)

    New scientific and engineering fundamentals of fuels substitution have been developed instead of obsolete methodology “Interchangeability of Fuel Gases” developed in USA and existing from the middle of XXth century. To perform the complex prediction of total or partial substitution of given flow rate of natural gas NG for alternative gases AG the following parameters are to be predicted: plant utilization efficiencies – regarding fuel and energy utilization, the last in form of heat ȘH and exergy Șeff efficiencies, saving or overexpenditure of the NG flow rate in the gas mixture with AG, specific fuel consumption b f and specific issue of harmful substances Ct – pollutants in the combustion products (CNOx ) and greenhouse gases (C CO2 ). Certification of alternative gas fuels and fuel mixtures as a commodity products is carried out in frame of our approach with necessary set of characteristics, similar to those accepted in the world practice. Key words: alternative fuel, fuel replacement (substitution), natural gas, process gases, theoretical combustion temperature, thermodynamic equilibrium computations, total enthalpy

  12. Dimethyl ether as alternative fuel for CI engine and vehicle

    Institute of Scientific and Technical Information of China (English)

    Zhen HUANG; Xinqi QIAO; Wugao ZHANG; Junhua WU; Junjun ZHANG

    2009-01-01

    As a developing and the most populous country in the world, China faces major challenges in energy supply and environmental protection. It is of great importance to develop clean and alternative fuels for internal combustion engines. On the basis of researches on DME engine and vehicle at Shanghai Jiaotong University in the last twelve years, fuel injection, combustion, performance and exhaust emissions of DME engine and DME vehicle are introduced in this paper. The results indicate that DME engines can achieve high thermal efficiency and ultra low emissions, and will play a significant role in meeting the energy demand while minimizing environmental impact in China.

  13. Greenfield Alternative Study LEU-Mo Fuel Fabrication Facility

    Energy Technology Data Exchange (ETDEWEB)

    Washington Division of URS

    2008-07-01

    This report provides the initial “first look” of the design of the Greenfield Alternative of the Fuel Fabrication Capability (FFC); a facility to be built at a Greenfield DOE National Laboratory site. The FFC is designed to fabricate LEU-Mo monolithic fuel for the 5 US High Performance Research Reactors (HPRRs). This report provides a pre-conceptual design of the site, facility, process and equipment systems of the FFC; along with a preliminary hazards evaluation, risk assessment as well as the ROM cost and schedule estimate.

  14. The California Multimedia Risk Assessment Protocol for Alternative Fuels

    Science.gov (United States)

    Hatch, T.; Ginn, T. R.; McKone, T. E.; Rice, D. W.

    2013-12-01

    Any new fuel in California requires approval by the state agencies overseeing human and environmental health. In order to provide a systematic evaluation of new fuel impacts, California now requires a multimedia risk assessment (MMRA) for fuel approval. The fuel MMRA involves all relevant state agencies including: the California Air Resources Board (CARB), the State Water Resources Control Board (SWRCB), the Office of Environmental Health Hazards Assessment (OEHHA), and the Department of Toxic Substances Control (DTSC) overseen by the California Environmental Protection Agency (CalEPA). The lead agency for MMRAs is the CARB. The original law requiring a multimedia assessment is California Health and Safety Code 43830.8. In addition, the low carbon fuel standard (LCFS), the Global Warming Solutions Act (AB32), and the Verified Diesel Emission Control Strategy (VDECS) have provisions that can require a multimedia assessment. In this presentation, I give an overview of the California multimedia risk assessment (MMRA) for new fuels that has been recently developed and applied to several alternative fuels. The objective of the California MMRA is to assess risk of potential impacts of new fuels to multiple environmental media including: air, water, and soil. Attainment of this objective involves many challenges, including varying levels of uncertainty, relative comparison of incommensurate risk factors, and differing levels of priority assigned to risk factors. The MMRA is based on a strategy of relative risk assessment and flexible accommodation of distinct and diverse fuel formulations. The approach is tiered by design, in order to allow for sequentially more sophisticated investigations as knowledge gaps are identified and re-prioritized by the ongoing research. The assessment also involves peer review in order to provide coupling between risk assessment and stakeholder investment, as well as constructive or confrontational feedback. The multimedia assessment

  15. Thorium - denatured uranium fuel cycles in PHWR-pressure tube type using low enriched uranium as annual externally supplied fissile material

    International Nuclear Information System (INIS)

    The use of denatured uranium as the initial fissile inventory of the thorium-uranium cycles could be straight-forward. The use of denatured uranium as annual externally supplied fissile material could be not applicable in the case of homogenous HWR fuel bundle concept if it is intended to avoid the shift from the Th/U cycle to U/Pu cycle or the reenrichment of the recycled uranium containing U-232. The paper presents a heterogenous fuel concept for HWR which permits the use of denatured uranium without the above-mentioned shift. According to this concept the annual externally supplied fissile material is introduced in distinct fuel rods separable at the front end of the reprocessing or as distinct fuel bundles. In these cases the normal reenrichment could be applied, this part of the fuel being free of U-233, and therefore free of U-232. The resource utilization penalties in addition to those introduced by the denaturing of the initial core were evaluated. At 3% enrichment these penalties rise with about 40% the annual natural uranium requirements. It is concluded that for these Th/U cycles in HWR, it is possible to avoid the presence of highly enriched uranium at the fuel fabrication step

  16. Thorium compounds processing at IPEN-CNEN/SP - Brazil and recent research initiatives

    International Nuclear Information System (INIS)

    Brazil has a long tradition in the thorium technology, from mining of monazite until the obtainment of high purity thorium compounds and IPEN has accumulated since the 60's a wide experience in the purification of thorium, obtained primarily from the monazite processing. Brazil has one of the biggest world nuclear resources (uranium and thorium), being the sixth natural uranium resource in the world (309,000 t U3O8), one of the first world thorium natural resource. The reasonably assured reserves and the estimated additional resources can reach 1.3 million metric tons of ThO2. Unfortunately, Brazil has not a thorium program and there never was a national program, lasting for a period sufficient to produce practical results of effective use of thorium in the Brazilian reactors. Worse, the specific research activities on different topics of the thorium cycle have declined over time, due to the lack of interest and support. An autonomous nuclear program was carried out in the country in the 80's. However, major political changes occurred in the program in the early 90's. These changes contributed to the further reduction of interest in alternative nuclear fuel cycles. Unfortunately, contrarily to what is happening in some countries in recent years, nowadays Brazil is paying little attention to the thorium, even less than in the past, despite its huge reserves. There are only limited and localized initiatives from some researchers. Some proposals would be an excellent opportunity to keep the existent capabilities in the institution that will be strategically important for the country in the future

  17. Nuclear power from thorium - different approaches

    International Nuclear Information System (INIS)

    The importance of thorium for sustainability of nuclear power has been recognized way back in 1950's. High abundance in nature, a higher neutron yield per fission over a wide range of neutron energy (in the thermal and epithermal range), single valency of thorium which leads to higher stabilities of it's compounds and much reduced production of long lived radioactive waste in the Th-233U fuel cycle have made thorium a very attractive source material for generation of nuclear energy. The thorium based fuel cycle is associated with the generation of 232U. Some of the daughter products of 232U have short half-lives and emit strong gamma rays. Therefore, 233U related activities such as fuel fabrication and subsequent fuel handling would need shielding and remote access. The first part of the paper will summarize the basic advantages and associated problems with the operation of thorium fuel cycle. Thorium being a fertile material, it's utilization in the power generation program requires judicious adoption of appropriate fuel cycles. Different approaches for thorium utilization in solid fuelled, molten salt and accelerator driven subcritical reactor and their merits and demerits will be discussed. The scientific issues connected with thorium in heavy water and light water reactors have been examined in terms of in-situ burning of 233U, saving in uranium, Pu generation, enhancement of burn up, and reprocessing challenges. Based on the analyses it has been argued that for a country such as India where the fissile inventory is not large and the policy of closed fuel cycle is adopted, an early introduction of thorium can only reduce uranium consumption to a limited extent. However, for gaining experience in thorium fuel cycle and for evaluating performance of thorium based fuel experimental irradiation of such fuels of different compositions are in progress. Molten salt reactors are quite promising for Th-233U fuel cycles both from safety and fissile

  18. On the assessment of the thorium cycle

    International Nuclear Information System (INIS)

    The high costs in the development of nuclear power have made it unpracticable to develop the uranium cycle and the thorium cycle simultaneously. Increasing awareness of the limited resources seems to cause a change of attitude towards the use of thorium. In the long run the thorium cycle can provide better fuel utilization than the uranium cycle. Commerzialization of the thorium cycle would give added flexibility to the world's nuclear industry in dealing with the delay in FBR introduction. Furthemore the thorium fuel cycle can reduce power costs under certain circumstances, particularly at higher U308-prices. The combination of converter and breeder to a symbiotic system appears to provide an attractive model to meet global energy needs in future. Since the thorium cycle involves recycling of bred 233U, remote refabrication will be required. Vibro-compaction of bulk-fuel, especially the sphere-pac-process for fabrication of fuel elements has attracted special attention because it comprises fewer mechanically intensive process steps than pellet technology. Owing to the high thermal stability of thorium, the advantages of metallic fuel may be used, but commonly oxide fuel will be preferred since the technology is well known. (author)

  19. Numerical Analysis of Emissions from Marine Engines Using Alternative Fuels

    Directory of Open Access Journals (Sweden)

    M.I. Lamas

    2015-12-01

    Full Text Available The current restrictions on emissions from marine engines, particularly sulphur oxides (SOx , nitrogen oxides (NOx and carbon dioxide (CO2 , are compelling the shipping industry to a change of tendency. In the recent years, many primary and secondary reduction techniques have been proposed and employed in marine engines. Nevertheless, the increasingly restrictive legislation makes it very difficult to continue developing efficient reduction procedures at competitive prices. According to this, the paper presents the possibility to employ alternative fuels. A numerical model was developed to analyze the combustion process and emissions using oil fuel, natural gas and hydrogen. A commercial marine engine was studied, the Wärtsilä 6L 46. It was found, that hydrogen is the cleanest fuel regarding CO2 , hydrocarbons (HC and carbon monoxide (CO. Nevertheless, it is very expensive for marine applications. Natural gas is cheaper and cleaner than fuel oil regarding CO2 and CO emissions. Still, natural gas emits more NOx and HC than oil fuel. SOx depends basically on the sulphur content of each particular fuel.

  20. Using Alcohols as an Alternative Fuel in Internal Combustion Engines

    OpenAIRE

    Salih ÖZER

    2014-01-01

    This study summarizes the studies on alcohol use in internal combustion engines nature. Nowadays, alcohol is used in internal combustion engines sometimes in order to reduce emissions and sometimes as an alternative fuel. Even vehicle manufacturers are producing and launching vehicles that are running directly with alcohol. Many types of pure alcohol that can be used on vehicles are available on the world. Using all of these types of alcohol led to the formation of engine emissions and power ...

  1. Biofuels – alternative to the traditional fuels in transport

    OpenAIRE

    Vanya Zhivkova

    2011-01-01

    In the article there is made a critical survey of some possibilities and issues, connected with the use of biofuels as an alternative to the traditional fuels in transport, for which there is used the descriptive - analytical method. There is clarified the n ature of biofuels, the kinds of biofuels, their advantages and disadvantages. Also presented is the state and development of the production of biofuels in Bulgaria. There is traced the evolution and the localization of the production of b...

  2. Thorium: Does Crustal Abundance Lead to Economic Availability?

    OpenAIRE

    Brett W. Jordan; Rod Eggert; Brent Dixon; Brett Carlsen

    2014-01-01

    Recently, interest in thorium's potential use in a nuclear fuel cycle has been renewed. Thorium is more abundant, at least on average, than uranium in the earth's crust and, therefore, could theoretically extend the use of nuclear energy technology beyond the economic limits of uranium resources. This paper provides an economic assessment of thorium availability by creating cumulative-availability and potential mining-industry cost curves, based on known thorium resources. These tools provide...

  3. Low Floor Americans with Disabilities Compliant Alternate Fuel Vehicle Project

    Energy Technology Data Exchange (ETDEWEB)

    James Bartel

    2004-11-26

    This project developed a low emission, cost effective, fuel efficient, medium-duty community/transit shuttle bus that meets American's with Disabilities Act (ADA) requirements and meets National Energy Policy Act requirements (uses alternative fuel). The Low Profile chassis, which is the basis of this vehicle is configured to be fuel neutral to accommodate various alternative fuels. Demonstration of the vehicle in Yellowstone Park in summer (wheeled operation) and winter (track operation) demonstrated the feasibility and flexibility for this vehicle to provide year around operation throughout the Parks system as well as normal transit operation. The unique configuration of the chassis which provides ADA access with a simple ramp and a flat floor throughout the passenger compartment, provides maximum access for all passengers as well as maximum flexibility to configure the vehicle for each application. Because this product is derived from an existing medium duty truck chassis, the completed bus is 40-50% less expensive than existing low floor transit buses, with the reliability and durability of OEM a medium duty truck.

  4. Impact of Thorium Capture Cross Section Uncertainty on the Thorium Utilized ADS Reactivity Calculation

    Directory of Open Access Journals (Sweden)

    Thanh Mai Vu

    2014-01-01

    Full Text Available Recently, the researches on fast neutron spectrum system utilized thorium fuel are widely conducted. However, the recent thorium cross section libraries are limited compared to uranium cross section libraries. The impact of thorium cross section uncertainty on thorium fuel utilized accelerator driven system (ADS reactivity calculation is estimated in this study. The uncertainty of the keff caused by 232Th capture cross section of JENDL-4.0 is about 1.3%. The uncertainty of JENDL-4.0 is needed to be enhanced to provide more reliable results on reactivity calculation for the fast system. The impact of uncertainty of  232Th capture cross section of ENDF/B-VII is small (0.1%. Therefore, it will cause no significant impact of the thorium cross section library on the thorium utilized ADS design calculation.

  5. Environmental consequences of uranium atmospheric releases from fuel cycle facility: II. The atmospheric deposition of uranium and thorium on plants.

    Science.gov (United States)

    Pourcelot, L; Masson, O; Renaud, P; Cagnat, X; Boulet, B; Cariou, N; De Vismes-Ott, A

    2015-03-01

    Uranium and thorium isotopes were measured in cypress leaves, wheat grains and lettuce taken in the surroundings of the uranium conversion facility of Malvési (South of France). The comparison of activity levels and activity ratios (namely (238)U/(232)Th and (230)Th/(232)Th) in plants with those in aerosols taken at this site and plants taken far from it shows that aerosols emitted by the nuclear site (uranium releases in the atmosphere by stacks and (230)Th-rich particles emitted from artificial ponds collecting radioactive waste mud) accounts for the high activities recorded in the plant samples close to the site. The atmospheric deposition process onto the plants appears to be the dominant process in plant contamination. Dry deposition velocities of airborne uranium and thorium were measured as 4.6 × 10(-3) and 5.0 × 10(-3) m s(-1), respectively. PMID:25500060

  6. Environmental releases from fuel cycle facility: part 1: radionuclide resuspension vs. stack releases on ambient airborne uranium and thorium levels

    International Nuclear Information System (INIS)

    Airborne activity levels of uranium and thorium series were measured in the vicinity (1.1 km) of a uranium (UF4) processing plant, located in Malvési, south of France. Regarding its impact on the environment, this facility is characterized by its routine atmospheric releases of uranium and by the emission of radionuclide-labelled particles from a storage pond filled with waste water or that contain dried sludge characterized by traces of plutonium and thorium (230Th). This study was performed during a whole year (November 2009–November 2010) and based on weekly aerosol sampling. Thanks to ICP-MS results, it was possible to perform investigations of uranium and thorium decay product concentration in the air. The number of aerosol filters sampled (50) was sufficient to establish a relationship between airborne radionuclide variations and the wind conditions. As expected, the more the time spent in the plume, the higher the ambient levels. The respective contributions of atmospheric releases and resuspension from local soil and waste ponds on ambient dust load and uranium-bearing aerosols were estimated. Two shutdown periods dedicated to facility servicing made it possible to estimate the resuspension contribution and to specify its origin (local or regional) according to the wind direction and remote background concentration. Airborne uranium mainly comes from the emission stack and, to a minor extent (∼20%), from wind resuspension of soil particles from the surrounding fields and areas devoted to waste storage. Moreover, weighed activity levels were clearly higher during operational periods than for shutdown periods. - Highlights: • Airborne activity levels of uranium and thorium were determined at about 1 km from the smokestack of a UF4 facility. • During shutdown periods all the airborne activity can be ascribed to local resuspension of formerly deposited radionuclides. • During production periods, the respective contribution of resuspension

  7. State and Alternative Fuel Provider Fleets Alternative Compliance; U.S. Department of Energy (DOE), Energy Efficiency & Renewable Energy (EERE)

    Energy Technology Data Exchange (ETDEWEB)

    None

    2015-08-01

    The final rule of the Energy Policy Act of 2005 and its associated regulations enable covered state and alternative fuel provider fleets to obtain waivers from the alternative fuel vehicle (AFV)-acquisition requirements of Standard Compliance. Under Alternative Compliance, covered fleets instead meet a petroleum-use reduction requirement. This guidance document is designed to help fleets better understand the Alternative Compliance option and successfully complete the waiver application process.

  8. Nuclear data covariances and sensitivity analysis, validation of a methodology based on the perturbation theory; application to an innovative concept: the molten thorium salt fueled reactor

    International Nuclear Information System (INIS)

    Neutron transport simulation of nuclear reactors is based on the knowledge of the neutron-nucleus interaction (cross-sections, fission neutron yields and spectra...) for the dozens of nuclei present in the core over a very large energy range (fractions of eV to several MeV). To obtain the goal of the sustainable development of nuclear power, future reactors must have new and more strict constraints to their design: optimization of ore materials will necessitate breeding (generation of fissile material from fertile material), and waste management will require transmutation. Innovative reactors that could achieve such objectives - generation IV or ADS (accelerator driven system) - are loaded with new fuels (thorium, heavy actinides) and function with neutron spectra for which nuclear data do not benefit from 50 years of industrial experience, and thus present particular challenges. After validation on an experimental reactor using an international benchmark, we take classical reactor physics tools along with available nuclear data uncertainties to calculate the sensitivities and uncertainties of the criticality and temperature coefficient of a thorium molten salt reactor. In addition, a study based on the important reaction rates for the calculation of cycle's equilibrium allows us to estimate the efficiency of different reprocessing strategies and the contribution of these reaction rates on the uncertainty of the breeding and then on the uncertainty of the size of the reprocessing plant. Finally, we use this work to propose an improvement of the high priority experimental request list. (author)

  9. Alternative Measuring Approaches in Gamma Scanning on Spent Nuclear Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Sihm Kvenangen, Karen

    2007-06-15

    In the future, the demand for energy is predicted to grow and more countries plan to utilize nuclear energy as their source of electric energy. This gives rise to many important issues connected to nuclear energy, such as finding methods that can verify that the spent nuclear fuel has been handled safely and used in ordinary power producing cycles as stated by the operators. Gamma ray spectroscopy is one method used for identification and verification of spent nuclear fuel. In the specific gamma ray spectroscopy method called gamma scanning the gamma radiation from the fission products Cs-137, Cs-134 and Eu-154 are measured in a spent fuel assembly. From the results, conclusions can be drawn about the fuels characteristics. This degree project examines the possibilities of using alternative measuring approaches when using the gamma scanning method. The focus is on examining how to increase the quality of the measured data. How to decrease the measuring time as compared with the present measuring strategy, has also been investigated. The main part of the study comprises computer simulations of gamma scanning measurements. The simulations have been validated with actual measurements on spent nuclear fuel at the central interim storage, Clab. The results show that concerning the quality of the measuring data the conventional strategy is preferable, but with other starting positions and with a more optimized equipment. When focusing on the time aspect, the helical measuring strategy can be an option, but this needs further investigation.

  10. Alternative Measuring Approaches in Gamma Scanning on Spent Nuclear Fuel

    International Nuclear Information System (INIS)

    In the future, the demand for energy is predicted to grow and more countries plan to utilize nuclear energy as their source of electric energy. This gives rise to many important issues connected to nuclear energy, such as finding methods that can verify that the spent nuclear fuel has been handled safely and used in ordinary power producing cycles as stated by the operators. Gamma ray spectroscopy is one method used for identification and verification of spent nuclear fuel. In the specific gamma ray spectroscopy method called gamma scanning the gamma radiation from the fission products Cs-137, Cs-134 and Eu-154 are measured in a spent fuel assembly. From the results, conclusions can be drawn about the fuels characteristics. This degree project examines the possibilities of using alternative measuring approaches when using the gamma scanning method. The focus is on examining how to increase the quality of the measured data. How to decrease the measuring time as compared with the present measuring strategy, has also been investigated. The main part of the study comprises computer simulations of gamma scanning measurements. The simulations have been validated with actual measurements on spent nuclear fuel at the central interim storage, Clab. The results show that concerning the quality of the measuring data the conventional strategy is preferable, but with other starting positions and with a more optimized equipment. When focusing on the time aspect, the helical measuring strategy can be an option, but this needs further investigation

  11. Criticality and burn up evolutions of the Fixed Bed Nuclear Reactor with alternative fuels

    International Nuclear Information System (INIS)

    Time evolution of criticality and burn-up grades of the Fixed Bed Nuclear Reactor (FBNR) are investigated for alternative fuels. These are: (1) low enriched uranium, (2) weapon grade plutonium, (3) reactor grade plutonium, and (4) minor actinides in the spent fuel of light water reactors (LWRs). The criticality calculations are conducted with SCALE 5.1 using S8-P3 approximation in 238 neutron energy groups with 90 groups in thermal energy region. The main results of the study can be summarized as follows: (1)Low enriched uranium (UO2): FBNR with an enrichment grade of 9% and 19% will start with keff = 1.2744 and keff = 1.36 and can operate ∼8 and >15 years with the same fuel charge, where criticality drops to keff = 1.06 and a burn-up grade of 54 000 and >110 000 MW.D/t can be attained. (2)Weapon grade plutonium: Such a high quality nuclear fuel suggests to be mixed with thorium. Second series of criticality calculations are conducted with fuel compositions made of thoria (ThO2) and weapon grade PuO2, where PuO2 component has been varied from 1% to 100%. Criticality with keff > 1.0 is achieved by ∼2.5% PuO2. At 4% PuO2, the reactor criticality will become satisfactory (keff = 1.1121), rapidly increasing with more PuO2. A reasonable mixture will by around 20% PuO2 and 80% ThO2 with a keff = 1.2864. This mixed fuel would allow full power reactor operation for >20 years and burn-up grade can reach 136 000 MW.D/t. (3)Reactor grade plutonium: Third series of criticality calculations are conducted with fuel compositions made of thoria and reactor grade PuO2, where PuO2 is varied from 1% to 100%. Reactor becomes critical by ∼8% PuO2 content. One can achieve keff = 1.2670 by 35% PuO2 and would allow full power reactor operation also for >20 years and burn-up grade can reach 123 000 MW.D/t. (4)Minor actinides in the spent fuel of LWRs: Fourth series of criticality calculations are conducted with fuel compositions made of thoria and MAO2, where MAO2 is varied from 1

  12. Advanced Proliferation Resistant, Lower Cost, Uranium-Thorium Dioxide Fuels for Light Water Reactors (Progress report for work through June 2002, 12th quarterly report)

    Energy Technology Data Exchange (ETDEWEB)

    Mac Donald, Philip Elsworth

    2002-09-01

    The overall objective of this NERI project is to evaluate the potential advantages and disadvantages of an optimized thorium-uranium dioxide (ThO2/UO2) fuel design for light water reactors (LWRs). The project is led by the Idaho National Engineering and Environmental Laboratory (INEEL), with the collaboration of three universities, the University of Florida, Massachusetts Institute of Technology (MIT), and Purdue University; Argonne National Laboratory; and all of the Pressurized Water Reactor (PWR) fuel vendors in the United States (Framatome, Siemens, and Westinghouse). In addition, a number of researchers at the Korean Atomic Energy Research Institute and Professor Kwangheon Park at Kyunghee University are active collaborators with Korean Ministry of Science and Technology funding. The project has been organized into five tasks: · Task 1 consists of fuel cycle neutronics and economics analysis to determine the economic viability of various ThO2/UO2 fuel designs in PWRs, · Task 2 will determine whether or not ThO2/UO2 fuel can be manufactured economically, · Task 3 will evaluate the behavior of ThO2/UO2 fuel during normal, off-normal, and accident conditions and compare the results with the results of previous UO2 fuel evaluations and U.S. Nuclear Regulatory Commission (NRC) licensing standards, · Task 4 will determine the long-term stability of ThO2/UO2 high-level waste, and · Task 5 consists of the Korean work on core design, fuel performance analysis, and xenon diffusivity measurements.

  13. Thorium Energy for the World

    CERN Document Server

    Revol, Jean-Pierre; Bourquin, Maurice; Kadi, Yacine; Lillestol, Egil; De Mestral, Jean-Christophe; Samec, Karel

    2016-01-01

    The Thorium Energy Conference (ThEC13) gathered some of the world’s leading experts on thorium technologies to review the possibility of destroying nuclear waste in the short term, and replacing the uranium fuel cycle in nuclear systems with the thorium fuel cycle in the long term. The latter would provide abundant, reliable and safe energy with no CO2 production, no air pollution, and minimal waste production. The participants, representatives of 30 countries, included Carlo Rubbia, Nobel Prize Laureate in physics and inventor of the Energy Amplifier; Jack Steinberger, Nobel Prize Laureate in physics; Hans Blix, former Director General of the International Atomic Energy Agency (IAEA); Rolf Heuer, Director General of CERN; Pascal Couchepin, former President of the Swiss Confederation; and Claude Haegi, President of the FEDRE, to name just a few. The ThEC13 proceedings are a source of reference on the use of thorium for energy generation. They offer detailed technical reviews of the status of thorium energy ...

  14. Development of biomass as an alternative fuel for gas turbines

    Energy Technology Data Exchange (ETDEWEB)

    Hamrick, J T [Aerospace Research Corp., Roanoke, VA (USA)

    1991-04-01

    A program to develop biomass as an alternative fuel for gas turbines was started at Aerospace Research Corporation in 1980. The research culminated in construction and installation of a power generation system using an Allison T-56 gas turbine at Red Boiling Springs, Tennessee. The system has been successfully operated with delivery of power to the Tennessee Valley Authority (TVA). Emissions from the system meet or exceed EPA requirements. No erosion of the turbine has been detected in over 760 hours of operation, 106 of which were on line generating power for the TVA. It was necessary to limit the turbine inlet temperature to 1450{degrees}F to control the rate of ash deposition on the turbine blades and stators and facilitate periodic cleaning of these components. Results of tests by researchers at Battelle Memorial Institute -- Columbus Division, give promise that deposits on the turbine blades, which must be periodically removed with milled walnut hulls, can be eliminated with addition of lime to the fuel. Operational problems, which are centered primarily around the feed system and engine configuration, have been adequately identified and can be corrected in an upgraded design. The system is now ready for development of a commercial version. The US Department of Energy (DOE) provided support only for the evaluation of wood as an alternative fuel for gas turbines. However, the system appears to have high potential for integration into a hybrid system for the production of ethanol from sorghum or sugar cane. 7 refs., 23 figs., 18 tabs.

  15. Evaluation Framework for Alternative Fuel Vehicles: Sustainable Development Perspective

    Directory of Open Access Journals (Sweden)

    Dong-Shang Chang

    2015-08-01

    Full Text Available Road transport accounts for 72.06% of total transport CO2, which is considered a cause of climate change. At present, the use of alternative fuels has become a pressing issue and a significant number of automakers and scholars have devoted themselves to the study and subsequent development of alternative fuel vehicles (AFVs. The evaluation of AFVs should consider not only air pollution reduction and fuel efficiency but also AFV sustainability. In general, the field of sustainable development is subdivided into three areas: economic, environmental, and social. On the basis of the sustainable development perspective, this study presents an evaluation framework for AFVs by using the DEMATEL-based analytical network process. The results reveal that the five most important criteria are price, added value, user acceptance, reduction of hazardous substances, and dematerialization. Price is the most important criterion because it can improve the popularity of AFVs and affect other criteria, including user acceptance. Additional, the energy usage criterion is expected to significantly affect the sustainable development of AFVs. These results should be seriously considered by automakers and governments in developing AFVs.

  16. PWR and WWER thorium cycle calculation

    International Nuclear Information System (INIS)

    The first step of the investigation of the thorium fuel cycle with HELIOS 1.8 is validation of the results obtained from the code for this particular type of fuel. To complete this first task we performed calculation of the benchmark announced by IAEA in 1995. The benchmark was based on a simplified PWR model of the assembly with reduced fuel composition. This calculation was focused on a comparison of the methods and basic nuclear data. After successful validation of the code we focused our work on calculating the PWR and WWER thorium fuel cycles. The thorium cycle begins after the first use of UO2 fuel in the reactor as separation of plutonium from the burnt fuel. Separated plutonium is mixed with thorium and used as a new nuclear fuel in the reactor. For our calculation we prepared two variants of the assembly - the first variant is a homogeneous distribution and the second one is a non-homogenised distribution of thorium fuel in the assembly. The model of non-homogenised distribution of Pu-Th fuel was designed by replacing selected rods of the classical UO2 assembly by Pu-Th rods. These selected rods are distributed symmetrically in the assembly. Other rods in the assembly remain the same as in the classical UO2 assembly. The calculated and compared values are criticality and fuel composition as a function of burnup (Authors)

  17. Alternative bipolar plates design and manufacturing for PEM fuel cell

    International Nuclear Information System (INIS)

    Bipolar plates is one of the important components in fuel cell stack, it comprise up to 80% of the stack volume. Traditionally, these plates have been fabricated from graphite, owing to its chemical nobility, and high electrical and thermal conductivity; but these plates are brittle and relatively thick. Therefore increasing the stack volume and size. Alternatives to graphite are carbon-carbon composite, carbon-polymer composite and metal (aluminum, stainless steel, titanium and nickel based alloy). The use of coated and uncoated metal bipolar plates has received attention recently due to the simplicity of plate manufacturing. The thin nature of the metal substrate allows for smaller stack design with reduced weight. Lightweight coated metals as alternative to graphite plate is being developed. Beside the traditional method of machining and slurry molding, metal foam for bipolar plates fabrication seems to be a good alternative. The plates will be produced with titanium powder by Powder Metallurgy method using space holders technique to produce the meal foam flow-field. This work intends to facilitate the materials and manufacturing process requirements to produce cost effective foamed bipolar plates for fuel cell

  18. Taking an Alternative Route: A guide for fleet operators and individual owners using alternative fuels in cars and trucks

    International Nuclear Information System (INIS)

    Taking an Alternative Route is a 30-page guide for fleet managers and individual owners on using alternative fuels in cars and trucks. Discussed in detail are all fuels authorized for federal credits under the Energy Policy Act of 1992 (EPAct). The publication informs federal and state fleet managers about how to comply with EPAct, and provides information about the Clean Air Act Amendments

  19. Environmental impact of alternative fuel on Tehran air pollution

    International Nuclear Information System (INIS)

    Seventy percent of the air pollution in the city of Tehran stems from mobile sources, and in comparison with other major cities of the world, Iran's capital experiences one of the most polluted metropolitan areas. There exists a surplus of liquid petroleum gas (LPG) in the Persian Gulf and Iranian market, in addition, Iran possesses the second largest reservoir of natural gas in the world. These alternative energy resources create a favorable potential fuel for city of Tehran. Experiments carried out in Tehran indicate that in converting the taxis from gasoline to a dual fuel (LPG/gasoline) car or to a dual fuel natural gas vehicle (NGV) reduce all major pollutants (CO, HC, NOX, Pb) substantially. Following the author's recommendation, the number of LPG dispensing units in gas stations are increasing and the number of dual fuel taxis amount to several thousands in the metropolitan area. The conversion of diesel buses in the Tehran Public Transportation Corporation to natural gas (NGV) has been recommended by the author and vast experimental works are underway at the present time

  20. Advanced materials for alternative fuel capable directly fired heat engines

    Energy Technology Data Exchange (ETDEWEB)

    Fairbanks, J.W.; Stringer, J. (eds.)

    1979-12-01

    The first conference on advanced materials for alternative fuel capable directly fired heat engines was held at the Maine Maritime Academy, Castine, Maine. It was sponsored by the US Department of Energy, (Assistant Secretary for Fossil Energy) and the Electric Power Research Institute, (Division of Fossil Fuel and Advanced Systems). Forty-four papers from the proceedings have been entered into EDB and ERA and one also into EAPA; three had been entered previously from other sources. The papers are concerned with US DOE research programs in this area, coal gasification, coal liquefaction, gas turbines, fluidized-bed combustion and the materials used in these processes or equipments. The materials papers involve alloys, ceramics, coatings, cladding, etc., and the fabrication and materials listing of such materials and studies involving corrosion, erosion, deposition, etc. (LTN)

  1. Environmental releases from fuel cycle facility: part 1: radionuclide resuspension vs. stack releases on ambient airborne uranium and thorium levels.

    Science.gov (United States)

    Masson, Olivier; Pourcelot, Laurent; Boulet, Béatrice; Cagnat, Xavier; Videau, Gérard

    2015-03-01

    Airborne activity levels of uranium and thorium series were measured in the vicinity (1.1 km) of a uranium (UF4) processing plant, located in Malvési, south of France. Regarding its impact on the environment, this facility is characterized by its routine atmospheric releases of uranium and by the emission of radionuclide-labelled particles from a storage pond filled with waste water or that contain dried sludge characterized by traces of plutonium and thorium ((230)Th). This study was performed during a whole year (November 2009-November 2010) and based on weekly aerosol sampling. Thanks to ICP-MS results, it was possible to perform investigations of uranium and thorium decay product concentration in the air. The number of aerosol filters sampled (50) was sufficient to establish a relationship between airborne radionuclide variations and the wind conditions. As expected, the more the time spent in the plume, the higher the ambient levels. The respective contributions of atmospheric releases and resuspension from local soil and waste ponds on ambient dust load and uranium-bearing aerosols were estimated. Two shutdown periods dedicated to facility servicing made it possible to estimate the resuspension contribution and to specify its origin (local or regional) according to the wind direction and remote background concentration. Airborne uranium mainly comes from the emission stack and, to a minor extent (∼20%), from wind resuspension of soil particles from the surrounding fields and areas devoted to waste storage. Moreover, weighed activity levels were clearly higher during operational periods than for shutdown periods. PMID:25613358

  2. Feasibility to produce uranium-233 from thorium in PHWR

    International Nuclear Information System (INIS)

    Uranium-233 is a fissile isotope of uranium that is bred from thorium-232 as part of the thorium fuel cycle. It is used as fuel in nuclear reactor. 233U is produced by irradiating thorium in fast reactor or thermal reactor. In this paper feasibility to produce 233U by irradiation of fuel bundles of thorium mixed with plutonium or irradiation of thorium bundles along with slightly enriched Uranium bundles in 220 MWe and 540 MWe PHWRs has been studied. Study shows that production of 233U is possible by irradiating few fuel bundles of PuTh or Thorium bundles along with SEU bundles without affecting the power operation and the safety related parameters. (author)

  3. Advantages of liquid fluoride thorium reactor in comparison with light water reactor

    Energy Technology Data Exchange (ETDEWEB)

    Bahri, Che Nor Aniza Che Zainul, E-mail: anizazainul@gmail.com; Majid, Amran Ab.; Al-Areqi, Wadeeah M. [Nuclear Science Program, School of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor (Malaysia)

    2015-04-29

    Liquid Fluoride Thorium Reactor (LFTR) is an innovative design for the thermal breeder reactor that has important potential benefits over the traditional reactor design. LFTR is fluoride based liquid fuel, that use the thorium dissolved in salt mixture of lithium fluoride and beryllium fluoride. Therefore, LFTR technology is fundamentally different from the solid fuel technology currently in use. Although the traditional nuclear reactor technology has been proven, it has perceptual problems with safety and nuclear waste products. The aim of this paper is to discuss the potential advantages of LFTR in three aspects such as safety, fuel efficiency and nuclear waste as an alternative energy generator in the future. Comparisons between LFTR and Light Water Reactor (LWR), on general principles of fuel cycle, resource availability, radiotoxicity and nuclear weapon proliferation shall be elaborated.

  4. Advantages of liquid fluoride thorium reactor in comparison with light water reactor

    Science.gov (United States)

    Bahri, Che Nor Aniza Che Zainul; Majid, Amran Ab.; Al-Areqi, Wadeeah M.

    2015-04-01

    Liquid Fluoride Thorium Reactor (LFTR) is an innovative design for the thermal breeder reactor that has important potential benefits over the traditional reactor design. LFTR is fluoride based liquid fuel, that use the thorium dissolved in salt mixture of lithium fluoride and beryllium fluoride. Therefore, LFTR technology is fundamentally different from the solid fuel technology currently in use. Although the traditional nuclear reactor technology has been proven, it has perceptual problems with safety and nuclear waste products. The aim of this paper is to discuss the potential advantages of LFTR in three aspects such as safety, fuel efficiency and nuclear waste as an alternative energy generator in the future. Comparisons between LFTR and Light Water Reactor (LWR), on general principles of fuel cycle, resource availability, radiotoxicity and nuclear weapon proliferation shall be elaborated.

  5. Advantages of liquid fluoride thorium reactor in comparison with light water reactor

    International Nuclear Information System (INIS)

    Liquid Fluoride Thorium Reactor (LFTR) is an innovative design for the thermal breeder reactor that has important potential benefits over the traditional reactor design. LFTR is fluoride based liquid fuel, that use the thorium dissolved in salt mixture of lithium fluoride and beryllium fluoride. Therefore, LFTR technology is fundamentally different from the solid fuel technology currently in use. Although the traditional nuclear reactor technology has been proven, it has perceptual problems with safety and nuclear waste products. The aim of this paper is to discuss the potential advantages of LFTR in three aspects such as safety, fuel efficiency and nuclear waste as an alternative energy generator in the future. Comparisons between LFTR and Light Water Reactor (LWR), on general principles of fuel cycle, resource availability, radiotoxicity and nuclear weapon proliferation shall be elaborated

  6. Determination of thorium in plutonium-thorium oxides and carbides

    International Nuclear Information System (INIS)

    Thorium is determined in (PuTh)C and (PuTh)O2 by complexometric titration with ethylenediaminetetraacetic acid (EDTA) following separation on anion-exchange resin. Carbides are first oxidized by ignition in air at about 8000C. Oxide or oxidized carbide samples are dissolved in acids by the sealed-reflux technique or by heating in beakers. The plutonium is selectively sorbed from the 12M hydrochloric acid solution of the fuel on a Bio-Rad AG1-X2 anion-exchange resin column, and the eluted thorium is titrated with EDTA using xylenol orange as the indicator. The average recovery of thorium in 20 samples is 99.98% with a relative standard deviation of 0.07%

  7. Impact of alternate fuels on industrial refractories and refractory insulation applications. An Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Wei, G.C.; Tennery, V.J.

    1976-09-01

    The effects of use of alternate fuels such as distillate oils, residual oils, coal, producer gas, and electricity on refractory insulation are evaluated. Sections are included on alternate fuels for 1976 to 1980, assessment by industry of fuel conversion impact on industrial refractories in the period 1976 to 1980, interactions of alternate fuel combustion products with refractories and refractory insulation, and analysis of degradation mechanisms in refractories and refractory materials. (JRD)

  8. EPAct Alternative Fuel Transportation Program: State and Alternative Fuel Provider Fleet Compliance Annual Report, Fleet Compliance Results for MY 2014/ FY 2015

    Energy Technology Data Exchange (ETDEWEB)

    2016-04-01

    This annual report of the Alternative Fuel Transportation Program, which ensures compliance with DOE regulations covering state government and alternative fuel provider fleets pursuant to the Energy Policy Act of 1992 (EPAct), as amended, provides fleet compliance results for manufacturing year 2014 / fiscal year 2015.

  9. Alternative Liquid Fuels Simulation Model (AltSim).

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Ryan; Baker, Arnold Barry; Drennen, Thomas E.

    2009-12-01

    The Alternative Liquid Fuels Simulation Model (AltSim) is a high-level dynamic simulation model which calculates and compares the production and end use costs, greenhouse gas emissions, and energy balances of several alternative liquid transportation fuels. These fuels include: corn ethanol, cellulosic ethanol from various feedstocks (switchgrass, corn stover, forest residue, and farmed trees), biodiesel, and diesels derived from natural gas (gas to liquid, or GTL), coal (coal to liquid, or CTL), and coal with biomass (CBTL). AltSim allows for comprehensive sensitivity analyses on capital costs, operation and maintenance costs, renewable and fossil fuel feedstock costs, feedstock conversion ratio, financial assumptions, tax credits, CO{sub 2} taxes, and plant capacity factor. This paper summarizes the structure and methodology of AltSim, presents results, and provides a detailed sensitivity analysis. The Energy Independence and Security Act (EISA) of 2007 sets a goal for the increased use of biofuels in the U.S., ultimately reaching 36 billion gallons by 2022. AltSim's base case assumes EPA projected feedstock costs in 2022 (EPA, 2009). For the base case assumptions, AltSim estimates per gallon production costs for the five ethanol feedstocks (corn, switchgrass, corn stover, forest residue, and farmed trees) of $1.86, $2.32, $2.45, $1.52, and $1.91, respectively. The projected production cost of biodiesel is $1.81/gallon. The estimates for CTL without biomass range from $1.36 to $2.22. With biomass, the estimated costs increase, ranging from $2.19 per gallon for the CTL option with 8% biomass to $2.79 per gallon for the CTL option with 30% biomass and carbon capture and sequestration. AltSim compares the greenhouse gas emissions (GHG) associated with both the production and consumption of the various fuels. EISA allows fuels emitting 20% less greenhouse gases (GHG) than conventional gasoline and diesels to qualify as renewable fuels. This allows several of the

  10. Thorium–based fuel cycles : saving uranium in a 200 MWth pebble bed high temperature reactor / S.K. Gintner

    OpenAIRE

    Gintner, Stephan Konrad

    2010-01-01

    The predominant nuclear fuel used globally at present is uranium which is a finite resource. Thorium has been identified as an alternative nuclear fuel source that can be utilized in almost all existing uranium–based reactors and can significantly help in conserving limited uranium reserves. Furthermore, the elimination of proliferation risks associated with thorium–based fuel cycles is a key reason for re–evaluating the possible utilization of thorium in high temperature reactors. In additio...

  11. Advisable alternative fuels for Mexico; Combustibles alternativos convenientes para Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar Gonzalez, Jorge Luis [ICA Fluor (Mexico)

    2007-07-15

    The alternative fuels are born with the goal of not damaging the environment; biodiesel, electricity, ethanol, hydrogen, methanol, natural gas, LP gas, are the main alternative fuels. However, the biodiesel and bioetanol are the only completely renewable ones, this makes them ideal to be developed in Mexico, since the agricultural sector could be fortified, the technological independence be favored, improve the conservation of the oil resources and by all means not to affect the environment. On the other hand, also efficient cultivation techniques should be developed to guarantee the economy of the process. [Spanish] Los combustibles alternativos nacen con la meta de no danar el medio ambiente; el biodiesel, electricidad, etanol, hidrogeno, metanol, gas natural, gas LP, son los principales combustibles alternativos. No obstante, el biodiesel y el bioetanol son los unicos completamente renovables, esto los hace ideales para desarrollarse en Mexico, ya que se podria fortalecer el sector agricola, favorecer la independencia tecnologica, mejorar la administracion de los recursos petroleros y por supuesto no afectar al medio ambiente. Por otro lado tambien se tendrian que desarrollar tecnicas de cultivo eficientes para garantizar la economia del proceso.

  12. DEVELOPMENT OF ALTERNATIVE FUELS AND CHEMICALS FROM SYNTHESIS GAS

    Energy Technology Data Exchange (ETDEWEB)

    Peter J. Tijrn

    2003-05-31

    This Final Report for Cooperative Agreement No. DE-FC22-95PC93052, the ''Development of Alternative Fuels and Chemicals from Synthesis Gas,'' was prepared by Air Products and Chemicals, Inc. (Air Products), and covers activities from 29 December 1994 through 31 July 2002. The overall objectives of this program were to investigate potential technologies for the conversion of synthesis gas (syngas), a mixture primarily of hydrogen (H{sub 2}) and carbon monoxide (CO), to oxygenated and hydrocarbon fuels and industrial chemicals, and to demonstrate the most promising technologies at the LaPorte, Texas Alternative Fuels Development Unit (AFDU). Laboratory work was performed by Air Products and a variety of subcontractors, and focused on the study of the kinetics of production of methanol and dimethyl ether (DME) from syngas, the production of DME using the Liquid Phase Dimethyl Ether (LPDME{trademark}) Process, the conversion of DME to fuels and chemicals, and the production of other higher value products from syngas. Four operating campaigns were performed at the AFDU during the performance period. Tests of the Liquid Phase Methanol (LPMEOH{trademark}) Process and the LPDME{trademark} Process were made to confirm results from the laboratory program and to allow for the study of the hydrodynamics of the slurry bubble column reactor (SBCR) at a significant engineering scale. Two campaigns demonstrated the conversion of syngas to hydrocarbon products via the slurry-phase Fischer-Tropsch (F-T) process. Other topics that were studied within this program include the economics of production of methyl tert-butyl ether (MTBE), the identification of trace components in coal-derived syngas and the means to economically remove these species, and the study of systems for separation of wax from catalyst in the F-T process. The work performed under this Cooperative Agreement has continued to promote the development of technologies that use clean syngas produced

  13. Thermodynamic analysis of SOFC (solid oxide fuel cell)–Stirling hybrid plants using alternative fuels

    International Nuclear Information System (INIS)

    A novel hybrid power system (∼10 kW) for an average family home is proposed. The system investigated contains a solid oxide fuel cell (SOFC) on top of a Stirling engine. The off-gases produced in the SOFC cycle are fed to a bottoming Stirling engine, at which additional power is generated. Simulations of the proposed system were conducted using different fuels, which should facilitate the use of a variety of fuels depending on availability. Here, the results for natural gas (NG), ammonia, di-methyl ether (DME), methanol and ethanol are presented and analyzed. The system behavior is further investigated by comparing the effects of key factors, such as the utilization factor and the operating conditions under which these fuels are used. Moreover, the effect of using a methanator on the plant efficiency is also studied. The combined system improves the overall electrical efficiency relative to that of a stand-alone Stirling engine or SOFC plant. For the combined SOFC and Stirling configuration, the overall power production was increased by approximately 10% compared to that of a stand-alone SOFC plant. System efficiencies of approximately 60% are achieved, which is remarkable for such small plant sizes. Additionally, heat is also produced to heat the family home when necessary. - Highlights: • Integrating a solid oxide fuel with a Stirling engine • Design of multi-fuel hybrid plants • Plants running on alternative fuels; natural gas, methanol, ethanol, DME and ammonia • Thermodynamic analysis of hybrid SOFC–Stirling engine plants

  14. Spent Fuel Characteristics Analyses for Thorium-Uranium Breeding Recycle in PWRs%压水堆内钍-铀增殖循环研究——乏燃料特性分析

    Institute of Scientific and Technical Information of China (English)

    毕光文; 司胜义; 张海俊

    2012-01-01

    利用ORIGEN-S程序对压水堆钍基乏燃料的特性进行分析,揭示了钍基乏燃料在放射性毒性、衰变热、γ射线等方面的特性,相关结果可为钍基乏燃料的贮存、后处理和地质处置提供必要的参考.研究的乏燃料是压水堆内钍-铀增殖循环堆芯设计方案中的4种,包括UOX(铀氧化物)、MOX(钚铀混合氧化物)、PuThOX(钚钍混合氧化物)和U3ThOX(工业级233 U-钍混合氧化物).研究结果表明:1)由于超铀核素的含量极低,在卸料后1000年内,U3ThOX的放射性毒性显著低于超铀核素含量高的乏燃料;2)由于232U衰变链中208T1的贡献,钍基乏燃料中2.6 MeV能量附近的γ射线强度明显高于铀基乏燃料,而这一能量附近的γ射线强度在卸料后约10年达到局部峰值,所以,钍基乏燃料的后处理最好避开此时间.%Spent fuel characteristics analyses of thorium-based fuel were investigated using ORIGEN-S code compared with uranium-based fuel. Such parameters as radioactivity, radiotoxicity, decay heat, and gamma ray were considered. Relative results in this work could provide some reference informations for storage, reprocessing and disposal of thorium-based spent fuel. Four type fuels, thorium-based fuel U3ThOX (mixed reactor grade 233U-thorium oxide), PuThOX (mixed reactor grade plutonium-thorium oxide) , uranium-based fuel UOX (uranium oxide) and MOX (mixed reactor grade plu-tonium-uranium oxide) , on the basis of core designs for thorium-uranium breeding recycle in PWRs were investigated. The calculated results show that: 1) Due to extremely low content of transuranic nuclides, the radiotoxicity of U3ThOX is dramatically lower than that of three other types of spent fuel in 1 000 years after discharge; 2) In thorium-based spent fuel the intensity of gamma ray near 2. 6 MeV mainly generated by 208Tl in 232 U decay chain is much stronger than that in uranium-based fuel. The intensity of y ray near 2. 6 MeV reaches a local peak in

  15. Fuel alternatives for oil sands development - the nuclear option

    International Nuclear Information System (INIS)

    Currently natural gas is the fuel of choice in all oil sand developments. Alberta sources of hydrocarbon based fuels are large but limited. Canadian nuclear technology was studied as a possible alternative for providing steam for the deep commercial in situ oil sand projects which were initiated over ten years ago. Because the in situ technology of that time required steam at pressures in excess of 10 MPa, the nuclear option required the development of new reactor technology, or the use of steam compressors, which was not economical. The current SAGD (steam assisted gravity drainage) technology requires steam at pressures of less than 5 MPa, which is in the reach of existing Canadian nuclear technology. The cost of supplying steam for a SAGD in situ project using a CANDU 3 nuclear reactor was developed. The study indicates that for gas prices in excess of $2.50 per gigajoule, replacing natural gas fuel with a nuclear reactor is economically feasible for in situ projects in excess of 123 thousand barrels per day. (author). 9 refs., 3 tabs., 12 figs

  16. Study of Temperature Gradient in Burning of Alternative Engine Fuels

    Directory of Open Access Journals (Sweden)

    M. S. Assad

    2008-01-01

    Full Text Available The paper gives an approximate method for calculation of the temperature at a final stage of fuel-air mixture burning in a closed vessel that is a combustion chamber of the internal combustion engine (ICE. The paper contains calculation of temperature values for various fuel-air mixtures, shows nature of temperature changes and presents analysis of combustion product temperature behaviour modification and analyzed the behaviour in accordance with an initial pressure in the chamber. The paper reveals the fact that a combustion temperature is increasing for all mixtures when an initial pressure in combustion chamber is increased. The hydrogen-air mixture has the highest combustion temperature among investigated mixtures and products of propane conversion have the lowest one.The Maxe-effect has been investigated in combustion of hydrogen-air mixture and design formulaes have been obtained. Calculation of temperature difference of the first and last portions of combustion products has been made with due account of the Maxe-effect.The proposed approximate method for calculation of temperatures indices in the various zones of combustion chamber in view of the Mach effect makes it possible to forecast thermodynamic nature of combustion process while using alternative engine fuels for internal combustion engine.

  17. LIQUID NATURAL GAS (LNG): AN ALTERNATIVE FUEL FROM LANDFILL GAS (LFG) AND WASTEWATER DIGESTER GAS

    Energy Technology Data Exchange (ETDEWEB)

    VANDOR,D.

    1999-03-01

    This Research and Development Subcontract sought to find economic, technical and policy links between methane recovery at landfill and wastewater treatment sites in New York and Maryland, and ways to use that methane as an alternative fuel--compressed natural gas (CNG) or liquid natural gas (LNG) -- in centrally fueled Alternative Fueled Vehicles (AFVs).

  18. Thorium-232

    International Nuclear Information System (INIS)

    This sheet belongs to a collection which relates to the use of radionuclides essentially in unsealed sources. Its goal is to gather on a single document the most relevant information as well as the best prevention practices to be implemented. These sheets are made for the persons in charge of radiation protection: users, radioprotection-skill persons, labor physicians. Each sheet treats of: 1 - the radio-physical and biological properties; 2 - the main uses; 3 - the dosimetric parameters; 4 - the measurement; 5 - the protection means; 6 - the areas delimitation and monitoring; 7 - the personnel classification, training and monitoring; 8 - the effluents and wastes; 9 - the authorization and declaration administrative procedures; 10 - the transport; and 11 - the right conduct to adopt in case of incident or accident. This sheet deals specifically with Thorium-232

  19. Content of Transuranium Nuclide in Process of Irradiating Thorium

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Currently, sufficient nuclear fuel supply is most important problem with the nuclear power grow rapidly, so the use of thorium fuel is being put on the agenda. The applicability of thorium as a power reactor is based on a (n, γ) reaction on 232Th. The consequent nucleus, 233Th,

  20. Thorium and health: state of the art

    International Nuclear Information System (INIS)

    This report reviews data available in the literature on the subject: 'thorium and health'. Thorium is a natural radioactive element of the actinide series. It is widely distributed in the earth's crust and 99% is found as isotope thorium-232. Its various uses are explained by its chemical, physical, and nuclear properties. As a potential nuclear fuel, thorium is still in demonstration in pilot scale reactors. But thorium has already multiple and sometimes unknown industrial uses. Some mass market products are concerned like light bulb. This raises the issue of wastes, and of exposures of workers and public. Environmental exposure via food and drink of the general population is low, where as workers can be exposed to significant doses, especially during ore extraction. Data on bio-monitoring of workers and biokinetic of thorium, in particular those provided by ICRP, are gathered here. Studies on health effects and toxicity of thorium are scarce and mostly old, except outcomes of its previous medical use. Studies on other forms of thorium should be undertaken to provide substantial data on its toxicity. Concerning treatment, Ca-DTPA is the recommended drug even if its efficacy is moderate. LiHOPO molecule shows interesting results in animals, and further research on chelating agents is needed. (authors)

  1. Thorium resources and energy utilization (14)

    International Nuclear Information System (INIS)

    After the accident at the Fukushima Daiichi Nuclear Power Station of Tokyo Electric Power Company, thorium reactor has been attracting attention from the viewpoint of safety. Regarding thorium as the resources for nuclear energy, this paper explains its estimated reserves in the whole world and each country, its features such as the situation of utilization, and the reason why it attracts attention now. The following three items are taken up here as the typical issues among the latest topics on thorium: (1) utilization of thorium as a tension easing measure against environmental effects involved in nuclear energy utilization, (2) thorium-based reactor as the next generation type reactor with improved safety, and (3) thorium utilization as the improvement policy of nuclear proliferation resistance. The outline, validity, and problems of these items are explained. Thorium reactor has been adopted as a research theme since the 1950s up to now mainly in the U.S. However, it is not enough in the aspect of technological development and also insufficient in the verification of reliability based on technological demonstration, compared with uranium-fueled light-water reactor. This paper explains these situations, and discusses the points for thorium utilization and future prospects. (A.O.)

  2. Solid fuel block as an alternate fuel for cooking and barbecuing: Preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Monikankana [Center for Energy, Indian Institute of Technology Guwahati, Guwahati 781 039 (India); Mukunda, H.S.; Sridhar, G. [Combustion Gasification Propulsion Laboratory, Department of Aerospace Engineering, Indian Institute of Science Bangalore, Bangalore 560 012 (India)

    2009-04-15

    A large part of the rural people of developing countries use traditional biomass stoves to meet their cooking and heating energy demands. These stoves possess very low thermal efficiency; besides, most of them cannot handle agricultural wastes. Thus, there is a need to develop an alternate cooking contrivance which is simple, efficient and can handle a range of biomass including agricultural wastes. In this reported work, a highly densified solid fuel block using a range of low cost agro residues has been developed to meet the cooking and heating needs. A strategy was adopted to determine the best suitable raw materials, which was optimized in terms of cost and performance. Several experiments were conducted using solid fuel block which was manufactured using various raw materials in different proportions; it was found that fuel block composed of 40% biomass, 40% charcoal powder, 15% binder and 5% oxidizer fulfilled the requirement. Based on this finding, fuel blocks of two different configurations viz. cylindrical shape with single and multi-holes (3, 6, 9 and 13) were constructed and its performance was evaluated. For instance, the 13 hole solid fuel block met the requirement of domestic cooking; the mean thermal power was 1.6 kW{sub th} with a burn time of 1.5 h. Furthermore, the maximum thermal efficiency recorded for this particular design was 58%. Whereas, the power level of single hole solid fuel block was found to be lower but adequate for barbecue cooking application. (author)

  3. Solid fuel block as an alternate fuel for cooking and barbecuing: Preliminary results

    International Nuclear Information System (INIS)

    A large part of the rural people of developing countries use traditional biomass stoves to meet their cooking and heating energy demands. These stoves possess very low thermal efficiency; besides, most of them cannot handle agricultural wastes. Thus, there is a need to develop an alternate cooking contrivance which is simple, efficient and can handle a range of biomass including agricultural wastes. In this reported work, a highly densified solid fuel block using a range of low cost agro residues has been developed to meet the cooking and heating needs. A strategy was adopted to determine the best suitable raw materials, which was optimized in terms of cost and performance. Several experiments were conducted using solid fuel block which was manufactured using various raw materials in different proportions; it was found that fuel block composed of 40% biomass, 40% charcoal powder, 15% binder and 5% oxidizer fulfilled the requirement. Based on this finding, fuel blocks of two different configurations viz. cylindrical shape with single and multi-holes (3, 6, 9 and 13) were constructed and its performance was evaluated. For instance, the 13 hole solid fuel block met the requirement of domestic cooking; the mean thermal power was 1.6 kWth with a burn time of 1.5 h. Furthermore, the maximum thermal efficiency recorded for this particular design was 58%. Whereas, the power level of single hole solid fuel block was found to be lower but adequate for barbecue cooking application

  4. Effect of Fuel Additives on Spray Performance of Alternative Jet Fuels

    Science.gov (United States)

    Kannaiyan, Kumaran; Sadr, Reza

    2015-11-01

    Role of alternative fuels on reducing the combustion pollutants is gaining momentum in both land and air transport. Recent studies have shown that addition of nanoscale metal particles as fuel additives to liquid fuels have a positive effect not only on their combustion performance but also in reducing the pollutant formation. However, most of those studies are still in the early stages of investigation with the addition of nanoparticles at low weight percentages. Such an addition can affect the hydrodynamic and thermo-physical properties of the fuel. In this study, the near nozzle spray performance of gas-to-liquid jet fuel with and without the addition of alumina nanoparticles are investigated at macro- and microscopic levels using optical diagnostic techniques. At macroscopic level, the addition of nanoparticles is seen to enhance the sheet breakup process when compared to that of the base fuel. Furthermore, the microscopic spray characteristics such as droplet size and velocity are also found to be affected. Although the addition of nanoscale metal particles at low weight percentages does not affect the bulk fluid properties, the atomization process is found to be affected in the near nozzle region. Funded by Qatar National Research Fund.

  5. Correlation of radioactive waste treatment costs and the environmental impact of waste effluents in the nuclear fuel cycle: fabrication of high-temperature gas-cooled reactor fuel containing uranium-233 and thorium

    International Nuclear Information System (INIS)

    A cost/benefit study was made to determine the cost and effectiveness of various radioactive waste (radwaste) treatment systems for decreasing the release of radioactive materials from model High-Temperature Gas-Cooled (HTGR) fuel fabrication plants and to determine the radiological impact (dose commitment) of the released materials on the environment. The study is designed to assist in defining the term ''as low as reasonably achievable'' as it applies to these nuclear facilities. The base cases of the two model plants, a fresh fuel fabrication plant and a refabrication plant, are representative of current proposed commercial designs or are based on technology that is being developed to fabricate uranium, thorium, and graphite into fuel elements. The annual capacities of the fresh fuel plant and the refabrication plant are 450 and 245 metric tons of heavy metal (where heavy metal is uranium plus thorium), as charged to about fifty 1000-MW(e) HTGRs. Additional radwaste treatment systems are added to the base case plants in a series of case studies to decrease the amounts of radioactive materials released and to reduce the radiological dose commitment to the population in the surrounding area. The capital and annual costs for the added waste treatment operations and the corresponding reductions in dose commitments are calculated for each case. In the final analysis, the cost/benefit of each case, calculated as additional cost of radwaste system divided by the reduction in dose commitment, is tabulated or the dose commitment is plotted with cost as the variable. The status of each of the radwaste treatment methods is discussed. 48 figures, 74 tables

  6. Correlation of radioactive waste treatment costs and the environmental impact of waste effluents in the nuclear fuel cycle: fabrication of high-temperature gas-cooled reactor fuel containing uranium-233 and thorium

    Energy Technology Data Exchange (ETDEWEB)

    Roddy, J.W.; Blanco, R.E.; Hill, G.S.; Moore, R.E.; Seagren, R.D.; Witherspoon, J.P.

    1976-06-01

    A cost/benefit study was made to determine the cost and effectiveness of various radioactive waste (radwaste) treatment systems for decreasing the release of radioactive materials from model High-Temperature Gas-Cooled (HTGR) fuel fabrication plants and to determine the radiological impact (dose commitment) of the released materials on the environment. The study is designed to assist in defining the term ''as low as reasonably achievable'' as it applies to these nuclear facilities. The base cases of the two model plants, a fresh fuel fabrication plant and a refabrication plant, are representative of current proposed commercial designs or are based on technology that is being developed to fabricate uranium, thorium, and graphite into fuel elements. The annual capacities of the fresh fuel plant and the refabrication plant are 450 and 245 metric tons of heavy metal (where heavy metal is uranium plus thorium), as charged to about fifty 1000-MW(e) HTGRs. Additional radwaste treatment systems are added to the base case plants in a series of case studies to decrease the amounts of radioactive materials released and to reduce the radiological dose commitment to the population in the surrounding area. The capital and annual costs for the added waste treatment operations and the corresponding reductions in dose commitments are calculated for each case. In the final analysis, the cost/benefit of each case, calculated as additional cost of radwaste system divided by the reduction in dose commitment, is tabulated or the dose commitment is plotted with cost as the variable. The status of each of the radwaste treatment methods is discussed. 48 figures, 74 tables.

  7. Utilization of Alternative Fuels in Cement Pyroprocessing : the Messebo Factory case study in Ethiopia

    OpenAIRE

    Ebuy Teka, Axumawi

    2015-01-01

    Energy costs and environmental standards encouraged cement manufacturers worldwide to evaluate to what extent conventional fuels (Furnace oil, Coal and Petcock) can be replaced by alternative fuels in cement production, i.e. biomass or processed waste materials like sewage sludge, MSW (municipal solid waste), Refuse Derived Fuels (RDF), Tire Derived Fuel (TDF), Plastic Derived Fuel (PDF), Biomass Derived Fuels (BDF), meat and bone meal (MBM), etc.  High temperature of >1500 C, long residen...

  8. Thorium utilization in a pebble bed reactor

    International Nuclear Information System (INIS)

    Thorium reserves in the earth's crust are much more than those of uranium, which today measure about 1.5 million tonnes of reasonably assured resources, plus 3 million tonnes of estimated additional resources. These large amount of thorium reserves, also available in Turkey encourages to focus on the utilization of thorium. The most remarkable applications of the use of thorium have been in high temperature reactors. The high temperature pebble bed reactor, which has been chosen as the basis for this study, is a close approximation of the thorium utilizing German reactor THTR. Pebble bed reactors have some unique features which are suitable to burn thorium. (i) The fuel is loaded in the form of coated particles, which are embedded in the graphite matrix of the fuel pebbles, allowing exceptionally high heavy metal burnups; and (ii) the continuous (on-line) fuel loading allows a high utilization factor. The criticality search of the pebble bed reactor is computed by the use of the SCALE4.4 code, CSASIX and KENOVa modules. And the in-core fuel management is computed via SCALE4.4 code, ORIGEN-S module

  9. Evaluation of alternative fuels for the Greek road transport sector using the analytic hierarchy process

    International Nuclear Information System (INIS)

    This paper evaluates alternative fuels for the Greek road transport sector, using the Analytic Hierarchy Process. Seven different alternatives of fuel mode are considered in this paper: internal combustion engine (ICE) and its combination with petroleum and 1st and 2nd generation biofuels blends, fuel cells, hybrid vehicles, plug-in hybrids and electric vehicles. The evaluation of alternative fuel modes is performed according to cost and policy aspects. In order to evaluate each alternative fuel, one base scenario and ten alternative scenarios with different weight factors selection per criterion are presented. After deciding the alternative fuels’ scoring against each criterion and the criteria weights, their synthesis gives the overall score and ranking for all ten alternative scenarios. It is concluded that ICE blended with 1st and 2nd generation biofuels are the most suitable alternative fuels for the Greek road transport sector. - Highlights: ► Alternative fuels for the Greek road transport sector have been evaluated. ► The method of the AHP was used. ► Seven different alternatives of fuel mode are considered. ► The evaluation is performed according to cost and policy aspects. ► The ICE with 1st and 2nd generation biofuels are the most suitable fuels.

  10. Emissions from Petrol Engine Fueled Gasoline–Ethanol–Methanol (GEM Ternary mixture as Alternative Fuel

    Directory of Open Access Journals (Sweden)

    Thangavelu Saravana Kannan

    2015-01-01

    Full Text Available The increasing demands of petroleum fuels due to the rapid development automotive society coupled with the environmental pollution issues have inspired the efforts on exploring alternative fuels for internal combustion engines. Bioethanol obtained from biomass and bioenergy crops has been proclaimed as one of the feasible alternative to gasoline. In this study, the effect of gasoline–ethanol–methanol (GEM ternary blend on the emission characteristics of petrol engine was studied. Three different fuel blends, namely, E0 (gasoline, G75E21M4 (75% gasoline, 21% hydrous ethanol and 4% methanol and E25 (25% anhydrous ethanol and 75% gasoline were tested in a 1.3-l K3-VE spark-ignition engine. The results indicate that, when G75E21M4 fuel blend was used, a significant drop in CO, CO2, NOx and HC emissions by about 42%, 15%, 7% and 5.2% compared to E0, respectively. Moreover, the emission results for G75E21M4 are marginally lower than E25 whereas; HC emission was slightly higher than E25.

  11. Using Alcohols as an Alternative Fuel in Internal Combustion Engines

    Directory of Open Access Journals (Sweden)

    Salih ÖZER

    2014-04-01

    Full Text Available This study summarizes the studies on alcohol use in internal combustion engines nature. Nowadays, alcohol is used in internal combustion engines sometimes in order to reduce emissions and sometimes as an alternative fuel. Even vehicle manufacturers are producing and launching vehicles that are running directly with alcohol. Many types of pure alcohol that can be used on vehicles are available on the world. Using all of these types of alcohol led to the formation of engine emissions and power curves. The studies reveal that these changes are because of the physical and chemical characteristics of alcohols. Thıs study tries to explain what kind of conclusions the physical and chemical properties cause

  12. 1982 worldwide synthetic fuels and alternate energy directory

    International Nuclear Information System (INIS)

    The purpose of this directory is to provide a complete list of companies, organizations, individuals, government agencies and educational institutions involved in the development of and the application of synthetic fuels and alternate energy sources. The directory features listings for groups involved in coal liquefaction and gasification, solar, geothermal, nuclear, oil shale, tar sands, heavy oil and biomass. Organizations appearing in this directory are arranged under three primary classifications: Industry, Government and Education. Under each of these three categories, each listing is arranged in alphabetical order by company name. Two indexes are provided with this directory. One index is arranged by subject and the other is a list of all companies appearing in the directory arranged in alphabetical order. Over 1500 companies are listed with descriptions of projects, key personnel and titles, names, addresses and phone numbers

  13. Harnessing thorium for nuclear power: challenges ahead

    International Nuclear Information System (INIS)

    There are several barriers to rapid growth of nuclear power. These arise as a result of concerns related to possible disasters arising out of severe accidents like Chernobyl and Fukushima, nuclear weapons proliferation, long term radioactive waste disposal etc. It is well known that use of thorium can actually address several of these concerns in a significant way. With developments in nuclear fuel technology, it is now possible to realise these gains through the use of thorium-LEU mixed fuel even in existing reactor systems without losing out too much on energy output from mined uranium in comparison to contemporary uranium fuelled reactor systems. Thorium thus offers an opportunity to facilitate a more rapid growth even with existing proven nuclear reactor designs while evolution of more optimum specific thorium reactor designs takes place. India with its experience base with thorium, while moving ahead with her domestic programme to evolve thorium reactor technology, could do well to facilitate growth of nuclear power through the use of thorium in currently established nuclear reactor designs. The presentation would discuss some of these possibilities

  14. Energy from thorium-an Indian perspective

    International Nuclear Information System (INIS)

    Nuclear energy as a sustainable resource in India has been very clearly formulated in the three stage nuclear programme. The role of thorium as a potential fuel in the third stage of this programme has also been elucidated. With this aim there have been pioneering research efforts in all aspects of the thorium fuel cycle. Thorium being fertile and not accompanied by the fissile species requires the use of a fissile topping. There have been several studies in India on the use of thorium in different reactor systems from thermal to intermediate and fast spectrum, molten salt reactors, high temperature reactors, compact nuclear power packs and even Subcritical systems. In this paper, we present some of the research studies on use of thorium in thermal reactor systems. We give an overview of the neutronic properties of thorium and the bred fissile material and then proceed to show the performance potential in different reactor systems. We also present the innovative Indian reactor designs which utilize thorium, namely the Advanced Heavy Water Reactor (AHWR) and the Indian High Temperature Reactors. (author)

  15. Transmutation of minor actinides in a Candu thorium borner

    International Nuclear Information System (INIS)

    The paper investigates the prospects of exploitation of rich world thorium reserves in CANDU reactors. Large quantities of plutonium have been accumulated in the nuclear waste of civilian LWRs and CANDU reactors. Reactor grade plutonium can be used as a booster fissile fuel material in form of mixed ThO2/PuO2 fuel in a CANDU fuel bundle in order to assure reactor criticality. Two different fuel compositions have been selected for investigations: 1) 96% thoria (ThO2) + 4% PuO2 and 2) 91% ThO2 + 5% UO2 + 4 PuO2. The latter is used for the purpose of denaturing the new 233U fuel with 238U. The behavior of the criticality k∞ and the burn-up values of the reactor have been pursued by full power operation for > ∼ 8 years. The reactor starts with k∞ = ∼ 1.39 and the criticality drops down asymptotically to values k∞ > 1.06, still tolerable and usable in a CANDU reactor. Reactor criticality k∞ remains nearly constant between the 4th year and 7th year of plant operation and then a slight increase is observed thereafter, along with a continuous depletion of thorium fuel. After the 2nd year, the CANDU reactor begins to operate practically as a thorium burner. Very high burn up can be achieved with the same fuel (> 160 000 MW.D/MT). The reactor criticality would be sufficient until a great fraction of the thorium fuel is burnt up, provided that the fuel rods could be fabricated to withstand such high burn up levels. Fuel fabrication costs and nuclear waste mass for final disposal per unit energy could be reduced drastically. There is a great quantity of weapon grade plutonium accumulated in nuclear stockpiles. In the second phase of investigations, weapon grade plutonium is used as a booster fissile fuel material in form of mixed ThO2/PuO2 fuel in a CANDU fuel bundle in order to assure the initial criticality at startup. Two different fuel compositions have been used: 1) 97% thoria (ThO2) + 3% PuO2 and 2) 92% ThO2 + 5% UO2 + 3% PuO2. The latter is used for

  16. The disposal of Canada's nuclear fuel waste: engineered barriers alternatives

    International Nuclear Information System (INIS)

    The concept for disposal of Canada's nuclear fuel waste involves emplacing the waste in a vault excavated at a depth of 500 to 1000 m in plutonic rock of the Canadian Shield. The solid waste would be isolated from the biosphere by a multibarrier system consisting of engineered barriers, including long-lived containers and clay and cement-based sealing materials, and the natural barrier provided by the massive geological formation. The technical feasibility of this concept and its impact on the environment and human health are being documented in an Environmental Impact Statement (EIS), which will be submitted for review under the federal Environmental Assessment and Review Process. This report, one of nine EIS primary references, describes the various alternative designs and materials for engineered barriers that have been considered during the development of the Canadian disposal concept and summarizes engineered barrier concepts being evaluated in other countries. The basis for the selection of a reference engineered barrier system for the EIS is presented. This reference system involves placing used CANDU (Canada Deuterium Uranium) fuel bundles in titanium containers, which would then be emplaced in boreholes drilled in the floor of disposal rooms. Clay-based sealing materials would be used to fill both the space between the containers and the rock and the remaining excavations. In the section on waste forms, the properties of both used-fuel bundles and solidified high-level wastes, which would be produced by treating wastes resulting from the reprocessing of used fuel, are discussed. Methods of solidifying the wastes and the chemical durability of the solidified waste under disposal conditions are reviewed. Various alternative container designs are reviewed, ranging from preliminary conceptual designs to designs that have received extensive prototype testing. Results of structural performance, welding and inspection studies are also summarized. The corrosion of

  17. The environmental behaviour of uranium and thorium

    International Nuclear Information System (INIS)

    Uranium and thorium have had many uses in the past, and their present and potential use as nuclear fuels in energy production is very significant. Both elements, and their daughter products, are of environmental interest because they may have effects from the time of mining to the time of ultimate disposal of used nuclear fuel. To assess the impact on the environment of man's use and disposal of uranium and thorium, we must know the physical, chemical and biological behaviour of these elements. This report summarizes the literature, updating and extending earlier reviews pertaining to uranium and thorium. The radiological properties, chemistry, forms of occurrence in nature, soil interactions, as well as distribution coefficients and mode of transport are discussed for both elements. In addition, uranium and thorium concentrations in plants, plant transfer coefficients, concentrations in soil organisms and methods of detection are summarized. (auth)

  18. Alternative Fuel Research in Fischer-Tropsch Synthesis

    Science.gov (United States)

    Surgenor, Angela D.; Klettlinger, Jennifer L.; Yen, Chia H.; Nakley, Leah M.

    2011-01-01

    NASA Glenn Research Center has recently constructed an Alternative Fuels Laboratory which is solely being used to perform Fischer-Tropsch (F-T) reactor studies, novel catalyst development and thermal stability experiments. Facility systems have demonstrated reliability and consistency for continuous and safe operations in Fischer-Tropsch synthesis. The purpose of this test facility is to conduct bench scale Fischer-Tropsch (F-T) catalyst screening experiments while focusing on reducing energy inputs, reducing CO2 emissions and increasing product yields within the F-T process. Fischer-Tropsch synthesis is considered a gas to liquid process which reacts syn-gas (a gaseous mixture of hydrogen and carbon monoxide), over the surface of a catalyst material which is then converted into liquids of various hydrocarbon chain length and product distributions1. These hydrocarbons can then be further processed into higher quality liquid fuels such as gasoline and diesel. The experiments performed in this laboratory will enable the investigation of F-T reaction kinetics to focus on newly formulated catalysts, improved process conditions and enhanced catalyst activation methods. Currently the facility has the capability of performing three simultaneous reactor screening tests, along with a fourth fixed-bed reactor used solely for cobalt catalyst activation.

  19. Safety implications of reactivity variations in fast thorium ADSRs

    International Nuclear Information System (INIS)

    Highlights: ► A lumped fast reactor model is used to simulate reactivity and power variations in a fast thorium ADSR. ► Neutron flux changes produce reactivity changes due to shifts in the 233Pa and 233U populations. ► On reactor start-up, the reactivity will fall in the early part of the burn-up. ► On reactor shutdown the reactivity will increase. ► A thorium fuelled ADSR operating at keff ⩾ 0.990 is at risk from an accelerator-trip-induced post-shutdown criticality excursion. - Abstract: Nuclear power generation offers a reliable, low-impact and large-scale alternative to fossil fuels. However, concerns exist over the safety and sustainability of this method of power production, and it remains unpopular with some governments and pressure groups throughout the world. Fast thorium fuelled accelerator-driven sub-critical reactors (ADSRs) offer a possible route to providing further re-assurance regarding these concerns on account of their properties of enhanced safety through sub-critical operation combined with reduced actinide waste production from the thorium fuel source. The appropriate sub-critical margin at which these reactors should operate is the subject of continued debate. Commercial interests favour a small sub-critical margin in order to minimise the size of the accelerator needed for a given power output, whilst enhanced safety would be better satisfied through larger sub-critical margins to further minimise the possibility of a criticality excursion. Against this background, this paper examines some of the issues affecting reactor safety inherent within thorium fuel sources resulting from the essential 23290Th→23390Th→23391Pa→23392U breeding chain. Differences in the decay half-lives and fission and capture cross-sections of 233Pa and 233U can result in significant changes in the reactivity of the fuel following changes in the reactor power. Reactor operation is represented using a homogeneous lumped fast reactor model that can

  20. Second interim report of the Interagency Commission on Alternative Motor Fuels

    International Nuclear Information System (INIS)

    This report describes progress the commission and government agencies have made in implementing the provisions of the Alternative Motor Fuels Act of 1988, assessing the role of alternative motor fuels in the US transportation sector, and developing policies to promote the use of alternative fuels. The alternative motor-fuels policies proposed in the National Energy Strategy (NES) are described and shows how they compose an effective long-term plan to encourage the widespread use of alternative motor fuels. The progress to date of the Department of Energy (DOE) and other agencies in implementing the programs required by the AMFA is reported. A detailed scenario of future alternative-fuel use that displaces 2.5 million barrels per day (MMBD) of petroleum and a feasible path of vehicle production and fuel supply leading to that goal is described. An analytical tool for exploring and quantifying the energy market impacts of alternative fuels, the Alternative Fuels Trade Model (AFTM), is described. The AFTM provides a means of investigating the impacts of alternative fuels in interrelated world energy markets for petroleum and natural gas. Several major initiatives have recently been enacted that have important ramifications for alternative-fuels policy. The Clean Air Act Amendments of 1990 contain provisions mandating the use of nonpetroleum oxygenates in reformulated gasoline. Other provisions for much more stringent emissions standards may affect the ability of manufacturers to make and sell conventional-fuel vehicles or, at the very least, affect their cost-effectiveness in comparison to cleaner alternative-fuel vehicles (AFV's). Finally, the key areas in which technological advances could substantially improve the competitiveness of AFV technologies in the marketplace are reviewed