Operational experience of the fuel cleaning facility of Joyo

Energy Technology Data Exchange (ETDEWEB)

Mukaibo, R; Matsuno, Y; Sato, I; Yoneda, Y; Ito, H [O-arai Engineering Centre, PNC, Ibaraki-ken, Tokio (Japan)

1978-08-01

Spent fuel assemblies in 'Joyo', after they are taken out of the core, are taken to the Fuel Cleaning Facility in the reactor service building and sodium removal is done. The cleaning process is done by cooling the assembly with argon gas, steam charging and rinsing by demineralized water. Deposited sodium was 50 {approx} 60 g per assembly. The sodium and steam reaction takes about 15 minutes to end and the total time the fuel is placed in the pot is about an hour. The total number of assemblies cleaned in the facility was 95 as of November 1977. In this report the operational experience together with discussions of future improvements are given. (author)

Nuclear combined cycle gas turbines for variable electricity and heat using firebrick heat storage and low-carbon fuels

International Nuclear Information System (INIS)

Forsberg, Charles; Peterson, Per F.; McDaniel, Patrick; Bindra, Hitesh

2017-01-01

The world is transitioning to a low-carbon energy system. Variable electricity and industrial energy demands have been met with storable fossil fuels. The low-carbon energy sources (nuclear, wind and solar) are characterized by high-capital-costs and low-operating costs. High utilization is required to produce economic energy. Wind and solar are non-dispatchable; but, nuclear is the dispatchable energy source. Advanced combined cycle gas turbines with firebrick heat storage coupled to high-temperature reactors may enable economic variable electricity and heat production with constant full-power reactor output. Such systems efficiently couple to fluoride-salt-cooled high-temperature reactors (FHRs) with solid fuel and clean salt coolants, molten salt reactors (MSRs) with fuel dissolved in the salt coolant and salt-cooled fusion machines. Open Brayton combined cycles allow the use of natural gas, hydrogen, other fuels and firebrick heat storage for peak electricity production with incremental heat-to-electricity efficiencies from 66 to 70+% efficient. There are closed Brayton cycle options that use firebrick heat storage but these have not been investigated in any detail. Many of these cycles couple to high-temperature gas-cooled reactors (HTGRs). (author)

Residual Inequity: Assessing the Unintended Consequences of New York City's Clean Heat Transition.

Science.gov (United States)

Carrión, Daniel; Lee, W Victoria; Hernández, Diana

2018-01-11

Energy policies and public health are intimately intertwined. In New York City, a series of policies, known as the Clean Heat Program (CHP), were designed to reduce air pollution by banning residual diesel fuel oils, #6 in 2015 and #4 by 2030. This measure is expected to yield environmental and public health benefits over time. While there is near-universal compliance with the #6 ban, a substantial number of buildings still use #4. In this paper, geographic analysis and qualitative interviews with stakeholders were used to interrogate the CHP's policy implementation in Northern Manhattan and the Bronx. A total of 1724 (53%) of all residential residual fuel burning buildings are located in this region. Stakeholders reflected mostly on the need for the program, and overall reactions to its execution. Major findings include that government partnerships with non-governmental organizations were effectively employed. However, weaknesses with the policy were also identified, including missed opportunities for more rapid transitions away from residual fuels, unsuccessful outreach efforts, cost-prohibitive conversion opportunities, and (the perception of) a volatile energy market for clean fuels. Ultimately, this analysis serves as a case study of a unique and innovative urban policy initiative to improve air quality and, consequently, public health.

Clean fuels from fossil sources

International Nuclear Information System (INIS)

Sanfilippo, D.

2000-01-01

Energy availability is determining to sustain the social development, but energy production involves environmental impacts at regional and global level. The central role of oil, natural gas, coal for energy supply will be kept for decades. The development of the engine-fuel combination to satisfy more stringent emissions limitations, is the challenge for an environmentally clean transportation system [it

Residual Inequity: Assessing the Unintended Consequences of New York City’s Clean Heat Transition

Science.gov (United States)

Carrión, Daniel; Lee, W. Victoria; Hernández, Diana

2018-01-01

Energy policies and public health are intimately intertwined. In New York City, a series of policies, known as the Clean Heat Program (CHP), were designed to reduce air pollution by banning residual diesel fuel oils, #6 in 2015 and #4 by 2030. This measure is expected to yield environmental and public health benefits over time. While there is near-universal compliance with the #6 ban, a substantial number of buildings still use #4. In this paper, geographic analysis and qualitative interviews with stakeholders were used to interrogate the CHP’s policy implementation in Northern Manhattan and the Bronx. A total of 1724 (53%) of all residential residual fuel burning buildings are located in this region. Stakeholders reflected mostly on the need for the program, and overall reactions to its execution. Major findings include that government partnerships with non-governmental organizations were effectively employed. However, weaknesses with the policy were also identified, including missed opportunities for more rapid transitions away from residual fuels, unsuccessful outreach efforts, cost-prohibitive conversion opportunities, and (the perception of) a volatile energy market for clean fuels. Ultimately, this analysis serves as a case study of a unique and innovative urban policy initiative to improve air quality and, consequently, public health. PMID:29324717

Residual Inequity: Assessing the Unintended Consequences of New York City’s Clean Heat Transition

Directory of Open Access Journals (Sweden)

Daniel Carrión

2018-01-01

Full Text Available Energy policies and public health are intimately intertwined. In New York City, a series of policies, known as the Clean Heat Program (CHP, were designed to reduce air pollution by banning residual diesel fuel oils, #6 in 2015 and #4 by 2030. This measure is expected to yield environmental and public health benefits over time. While there is near-universal compliance with the #6 ban, a substantial number of buildings still use #4. In this paper, geographic analysis and qualitative interviews with stakeholders were used to interrogate the CHP’s policy implementation in Northern Manhattan and the Bronx. A total of 1724 (53% of all residential residual fuel burning buildings are located in this region. Stakeholders reflected mostly on the need for the program, and overall reactions to its execution. Major findings include that government partnerships with non-governmental organizations were effectively employed. However, weaknesses with the policy were also identified, including missed opportunities for more rapid transitions away from residual fuels, unsuccessful outreach efforts, cost-prohibitive conversion opportunities, and (the perception of a volatile energy market for clean fuels. Ultimately, this analysis serves as a case study of a unique and innovative urban policy initiative to improve air quality and, consequently, public health.

Alternative fuel news: Official publication of the clean cities network and the alternative fuels data center, Vol. 4, No. 1

Energy Technology Data Exchange (ETDEWEB)

NREL

2000-03-27

This issue of Alternative Fuel News contains information on the upcoming Clean Cities Conference to be held May 7--10, 2000 in San Diego, California. Highlighted in this issue is the success of the Clean Cities Program in creating clean corridors that permit fleets that serve multiple cities to purchase AFVs with confidence, knowing that fueling convenience and supply will not be a problem. Also look for articles on electric vehicles, transit buses; state and fuel provider enforcement; the Salt Lake and Greater Long Island Clean Cities coalitions, HEVs and fuel cells are a big hit at auto shows; DOE awards alternative fuel grants to 33 National Parks; and the Energy Policy Act (EPAct) Section 506 report.

Engineering development of advanced physical fine coal cleaning for premium fuel applications

International Nuclear Information System (INIS)

1997-01-01

Bechtel, together with Amax Research and Development Center (Amax R ampersand D), has prepared this study which provides conceptual cost estimates for the production of premium quality coal-water slurry fuel (CWF) in a commercial plant. Two scenarios are presented, one using column flotation technology and the other the selective agglomeration to clean the coal to the required quality specifications. This study forms part of US Department of Energy program Engineering Development of Advanced Physical Fine Coal Cleaning for Premium Fuel Applications, (Contract No. DE-AC22- 92PC92208), under Task 11, Project Final Report. The primary objective of the Department of Energy program is to develop the design base for prototype commercial advanced fine coal cleaning facilities capable of producing ultra-clean coals suitable for conversion to stable and highly loaded CWF. The fuels should contain less than 2 lb ash/MBtu (860 grams ash/GJ) of HHV and preferably less than 1 lb ash/MBtu (430 grams ash/GJ). The advanced fine coal cleaning technologies to be employed are advanced column froth flotation and selective agglomeration. It is further stipulated that operating conditions during the advanced cleaning process should recover not less than 80 percent of the carbon content (heating value) in the run-of-mine source coal. These goals for ultra-clean coal quality are to be met under the constraint that annualized coal production costs does not exceed $2.5 /MBtu ($ 2.37/GJ), including the mine mouth cost of the raw coal. A further objective of the program is to determine the distribution of a selected suite of eleven toxic trace elements between product CWF and the refuse stream of the cleaning processes. Laboratory, bench-scale and Process Development Unit (PDU) tests to evaluate advanced column flotation and selective agglomeration were completed earlier under this program with selected coal samples. A PDU with a capacity of 2 st/h was designed by Bechtel and installed at

Northwest Region Clean Energy Application Center

Energy Technology Data Exchange (ETDEWEB)

Sjoding, David [Washington State Univ., Pullman, WA (United States)

2013-09-30

The main objective of the Northwest Clean Energy Application Center (NW CEAC) is to promote and support implementation of clean energy technologies. These technologies include combined heat and power (CHP), district energy, waste heat recovery with a primary focus on waste heat to power, and other related clean energy systems such as stationary fuel cell CHP systems. The northwest states include AK, ID, MT, OR, and WA. The key aim/outcome of the Center is to promote and support implementation of clean energy projects. Implemented projects result in a number of benefits including increased energy efficiency, renewable energy development (when using opportunity fuels), reduced carbon emissions, improved facility economics helping to preserve jobs, and reduced criteria pollutants calculated on an output-based emissions basis. Specific objectives performed by the NW CEAC fall within the following five broad promotion and support categories: 1) Center management and planning including database support; 2) Education and Outreach including plan development, website, target market workshops, and education/outreach materials development 3) Identification and provision of screening assessments & feasibility studies as funded by the facility or occasionally further support of Potential High Impact Projects; 4) Project implementation assistance/trouble shooting; and 5) Development of a supportive clean energy policy and initiative/financing framework.

The element technology of clean fuel alcohol plant construction

Energy Technology Data Exchange (ETDEWEB)

Lee, D S; Lee, D S [Sam-Sung Engineering Technical Institute (Korea, Republic of); Choi, C Y [Seoul National University, Seoul (Korea, Republic of); and others

1996-02-01

The fuel alcohol has been highlighted as a clean energy among new renewable energy sources. However, the production of the fuel alcohol has following problems; (i)bulk distillate remains is generated and (ii) benzene to be used as a entertainer in the azeotropic distillation causes the environmental problem. Thus, we started this research on the ground of preserving the cleanness in the production of fuel alcohol, a clean energy. We examined the schemes of replacing the azotropic distillation column which causes the problems with MSDP(Molecular Sieve Dehydration Process) system using adsorption technology and of treating the bulk distillate remains to be generated as by-products. In addition, we need to develop the continuous yea station technology for the continuous operation of fuel alcohol plant as a side goal. Thus, we try to develop a continuous ethanol fermentation process by high-density cell culture from tapioca, a industrial substrate, using cohesive yeast. For this purpose, we intend to examine the problem of tapioca, a industrial substrate, where a solid is existed and develop a new process which can solve the problem. Ultimately, the object of this project is to develop each element technology for the construction of fuel alcohol plant and obtain the ability to design the whole plant. (author) 54 refs., 143 figs., 34 tabs.

Clean fuel technology for world energy security

Energy Technology Data Exchange (ETDEWEB)

Sunjay, Sunjay

2010-09-15

Clean fuel technology is the integral part of geoengineering and green engineering with a view to global warming mitigation. Optimal utilization of natural resources coal and integration of coal & associated fuels with hydrocarbon exploration and development activities is pertinent task before geoscientist with evergreen energy vision with a view to energy security & sustainable development. Value added technologies Coal gasification,underground coal gasification & surface coal gasification converts solid coal into a gas that can be used for power generation, chemical production, as well as the option of being converted into liquid fuels.

Clean Cities Strategic Planning White Paper: Light Duty Vehicle Fuel Economy

Energy Technology Data Exchange (ETDEWEB)

Saulsbury, Bo [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hopson, Dr Janet L [Univ. of Tennessee, Knoxville, TN (United States); Greene, David [Univ. of Tennessee, Knoxville, TN (United States); Gibson, Robert [Univ. of Tennessee, Knoxville, TN (United States)

2015-04-01

Increasing the energy efficiency of motor vehicles is critical to achieving national energy goals of reduced petroleum dependence, protecting the global climate, and promoting continued economic prosperity. Even with fuel economy and greenhouse gas emissions standards and various economic incentives for clean and efficient vehicles, providing reliable and accurate fuel economy information to the public is important to achieving these goals. This white paper reviews the current status of light-duty vehicle fuel economy in the United States and the role of the Department of Energy (DOE) Clean Cities Program in disseminating fuel economy information to the public.

Identifying optimal cleaning cycles for heat exchangers subject to fouling and ageing

International Nuclear Information System (INIS)

Pogiatzis, Thomas; Ishiyama, Edward M.; Paterson, William R.; Vassiliadis, Vassilios S.; Wilson, D. Ian

2012-01-01

Fouling of heat exchangers causes reduced heat transfer and other penalties. Regular cleaning represents one widely used fouling mitigation strategy, where the schedule of cleaning actions can be optimised to minimise the cost of fouling. This paper investigates, for the first time, the situation where there are two cleaning methods available so that the mode of cleaning has to be selected as well as the cleaning interval. Ageing is assumed to convert the initial deposit, labelled 'gel', into a harder and more conductive form, labelled 'coke', which cannot be removed by one of the cleaning methods. The second method can remove both the gel layer and the coke layer, but costs more and requires the unit to be off-line longer for cleaning. Experimental data demonstrating the effects of ageing are presented. The industrial application is the comparison of cleaning-in-place methods with off-line mechanical cleaning. A process model is constructed for an isolated counter-current heat exchanger subject to fouling, where ageing is described by a simple two-layer model. Solutions generated by an NLP-based approach prove to be superior to a simpler heuristic. A series of case studies demonstrate that combinations of chemical and mechanical cleaning can be superior to mechanical cleaning alone for certain combinations of parameters.

Innovative technologies on fuel assemblies cleaning for sodium fast reactors: First considerations on cleaning process

International Nuclear Information System (INIS)

Simon, N.; Lorcet, H.; Beauchamp, F.; Guigues, E.; Lovera, P.; Fleche, J. L.; Lacroix, M.; Carra, O.; Dechelette, F.; Prele, G.; Rodriguez, G.

2012-01-01

Within the framework of Sodium Fast Reactor development, innovative fuel assembly cleaning operations are investigated to meet the GEN IV goals of safety and of process development. One of the challenges is to mitigate the Sodium Water Reaction currently used in these processes. The potential applications of aqueous solutions of mineral salts (including the possibility of using redox chemical reactions) to mitigate the Sodium Water Reaction are considered in a first part and a new experimental bench, dedicated to this study, is described. Anhydrous alternative options based on Na/CO 2 interaction are also presented. Then, in a second part, a functional study conducted on the cleaning pit is proposed. Based on experimental feedback, some calculations are carried out to estimate the sodium inventory on the fuel elements, and physical methods like hot inert gas sweeping to reduce this inventory are also presented. Finally, the implementation of these innovative solutions in cleaning pits is studied in regard to the expected performances. (authors)

Innovative technologies on fuel assemblies cleaning for sodium fast reactors: First considerations on cleaning process

Energy Technology Data Exchange (ETDEWEB)

Simon, N.; Lorcet, H.; Beauchamp, F.; Guigues, E. [CEA, DEN, DTN Cadarache, F-13108 Saint-Paul-lez-Durance (France); Lovera, P.; Fleche, J. L. [CEA, DEN, DPC Saclay, F-91191 Gif-sur-Yvette (France); Lacroix, M. [CEA, DEN, DTN Cadarache, F-13108 Saint-Paul-lez-Durance (France); Carra, O. [AREVA / NP, 10 Rue Juliette Recamier, 69003 Lyon (France); Dechelette, F. [CEA, DEN, DTN Cadarache, F-13108 Saint-Paul-lez-Durance (France); Prele, G. [EDF/SEPTEN, 12-14 avenue Dutrievoz, 69628 Villeurbane Cedex (France); Rodriguez, G. [CEA, DEN, DTN Cadarache, F-13108 Saint-Paul-lez-Durance (France)

2012-07-01

Within the framework of Sodium Fast Reactor development, innovative fuel assembly cleaning operations are investigated to meet the GEN IV goals of safety and of process development. One of the challenges is to mitigate the Sodium Water Reaction currently used in these processes. The potential applications of aqueous solutions of mineral salts (including the possibility of using redox chemical reactions) to mitigate the Sodium Water Reaction are considered in a first part and a new experimental bench, dedicated to this study, is described. Anhydrous alternative options based on Na/CO{sub 2} interaction are also presented. Then, in a second part, a functional study conducted on the cleaning pit is proposed. Based on experimental feedback, some calculations are carried out to estimate the sodium inventory on the fuel elements, and physical methods like hot inert gas sweeping to reduce this inventory are also presented. Finally, the implementation of these innovative solutions in cleaning pits is studied in regard to the expected performances. (authors)

ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT, JCH FUEL SOLUTIONS, INC., JCH ENVIRO AUTOMATED FUEL CLEANING AND MAINTENANCE SYSTEM

Science.gov (United States)

The verification testing was conducted at the Cl facility in North Las Vegas, NV, on July 17 and 18, 2001. During this period, engine emissions, fuel consumption, and fuel quality were evaluated with contaminated and cleaned fuel.To facilitate this verification, JCH repre...

Hot fuel gas dedusting after sorbent-based gas cleaning

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-07-01

Advanced power generation technologies, such as Air Blown Gasification Cycle (ABGC), require gas cleaning at high temperatures in order to meet environmental standards and to achieve high thermal efficiencies. The primary hot gas filtration process, which removes particulates from the cooled raw fuel gas at up to 600{degree}C is the first stage of gas cleaning prior to desulphurization and ammonia removal processes. The dust concentration in the fuel gas downstream of the sorbent processes would be much lower than for the hot gas filtration stage and would have a lower sulphur content and possibly reduced chlorine concentration. The main aim of this project is to define the requirements for a hot gas filter for dedusting fuel gas under these conditions, and to identify a substantially simpler and more cost effective solution using ceramic or metal barrier filters.

Wood fuel from early thinning and plantation cleaning. An international review

International Nuclear Information System (INIS)

Puttock, D.; Richardsson, J.

1998-01-01

Activities 1.2 (Forest management) and 1.2 (Harvesting) of Task XII/IEA Bioenergy Agreement carried out an international review of wood fuel from plantation cleaning and early thinning. The participating countries were Canada, Denmark, Finland, the Netherlands, New Zealand, Sweden and the United Kingdom. The individual country reviews and an international summary are presented in this paper. Each report gives country-related background information on forestry and wood utilization, energy potential from plantation cleaning and early thinning, environmental considerations from the viewpoint of wood fuel recovery, silvicultural systems and methods, cost of wood fuel, and knowledge gaps and problems

Study of a molten carbonate fuel cell combined heat, hydrogen and power system: Energy analysis

International Nuclear Information System (INIS)

Agll, Abdulhakim Amer A.; Hamad, Yousif M.; Hamad, Tarek A.; Thomas, Mathew; Bapat, Sushrut; Martin, Kevin B.; Sheffield, John W.

2013-01-01

Countries around the world are trying to use alternative fuels and renewable energy to reduce the energy consumption and greenhouse gas emissions. Biogas contains methane is considered a potential source of clean renewable energy. This paper discusses the design of a combined heat, hydrogen and power system, which generated by methane with use of Fuelcell, for the campus of Missouri University of Science and Technology located in Rolla, Missouri, USA. An energy flow and resource availability study was performed to identify sustainable type and source of feedstock needed to run the Fuelcell at its maximum capacity. FuelCell Energy's DFC1500 unit (a molten carbonate Fuelcell) was selected as the Fuelcell for the tri-generation (heat, hydrogen and electric power) system. This tri-generation system provides electric power to the campus, thermal energy for heating the anaerobic digester, and hydrogen for transportation, backup power and other applications on the campus. In conclusion, the combined heat, hydrogen and power system reduces fossil fuel usage, and greenhouse gas emissions at the university campus. -- Highlights: • Combined heat, hydrogen and power (CHHP) using a molten carbonate fuel cell. • Energy saving and alternative fuel of the products are determined. • Energy saving is increased when CHHP technology is implemented. • CHHP system reduces the greenhouse gas emissions and fuel consumption

Keeping condensers clean

Energy Technology Data Exchange (ETDEWEB)

Wicker, K.

2006-04-15

The humble condenser is among the biggest contributors to a steam power plant's efficiency. But although a clean condenser can provide great economic benefit, a dirty one can raise plant heat rate, resulting in large losses of generation revenue and/or unnecessarily high fuel bills. Conventional methods for cleaning fouled tubes range form chemicals to scrapers to brushes and hydro-blasters. This article compares the available options and describes how one power station, Omaha Public Power District's 600 MW North Omaha coal-fired power station, cleaned up its act. The makeup and cooling water of all its five units comes from the Missouri River. 6 figs.

Hydrogen as alternative clean fuel: Economic analysis

International Nuclear Information System (INIS)

Coiante, D.

1995-03-01

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

Experimental study on air cleaning effect of clean air heat pump and its impact on ventilation requirement

DEFF Research Database (Denmark)

Fang, Lei; Sheng, Ying; Nie, Jinzhe

2017-01-01

This study investigated air purification effect of a Clean-Air Heat Pump (CAHP) which combined a desiccant wheel with a heat pump for both air cleaning and HVAC of buildings. The experiment was conducted in a field lab at four different outdoor air supply rates with and without air cleaning by CAHP....... Both sensory assessments of perceived air quality and chemical measurements of TVOC concentrations were conducted for evaluating the air cleaning performance of the CAHP. The results of experiment showed that running the CAHP improved significantly perceived air quality. At 2 L/s per person of outdoor...... air supply rate with operating the CAHP, the air quality was equivalent to the value at the higher outdoor air supply rate of 10 L/s per person without running CAHP. The TVOC measurements observed over 92% of efficiency on removal of indoor air VOCs and no VOCs accumulation on the desiccant wheel...

Ethanol-fueled low temperature combustion: A pathway to clean and efficient diesel engine cycles

International Nuclear Information System (INIS)

Asad, Usman; Kumar, Raj; Zheng, Ming; Tjong, Jimi

2015-01-01

Highlights: • Concept of ethanol–diesel fueled Premixed Pilot Assisted Combustion (PPAC). • Ultra-low NOx and soot with diesel-like thermal efficiency across the load range. • Close to TDC pilot injection timing for direct combustion phasing control. • Minimum pilot quantity (15% of total energy input) for clean, stable operation. • Defined heat release profile distribution (HRPD) to optimize pilot-ethanol ratio. - Abstract: Low temperature combustion (LTC) in diesel engines offers the benefits of ultra-low NOx and smoke emissions but suffers from lowered energy efficiency due to the high reactivity and low volatility of diesel fuel. Ethanol from renewable biomass provides a viable alternate to the petroleum based transportation fuels. The high resistance to auto-ignition (low reactivity) and its high volatility make ethanol a suitable fuel for low temperature combustion (LTC) in compression-ignition engines. In this work, a Premixed Pilot Assisted Combustion (PPAC) strategy comprising of the port fuel injection of ethanol, ignited with a single diesel pilot injection near the top dead centre has been investigated on a single-cylinder high compression ratio diesel engine. The impact of the diesel pilot injection timing, ethanol to diesel quantity ratio and exhaust gas recirculation on the emissions and efficiency are studied at 10 bar IMEP. With the lessons learnt, successful ethanol–diesel PPAC has been demonstrated up to a load of 18 bar IMEP with ultra-low NOx and soot emissions across the full load range. The main challenge of PPAC is the reduced combustion efficiency especially at low loads; therefore, the authors have presented a combustion control strategy to allow high efficiency, clean combustion across the load range. This work entails to provide a detailed framework for the ethanol-fueled PPAC to be successfully implemented.

Effective technology of wood and gaseous fuel co-firing for clean energy production

International Nuclear Information System (INIS)

Zake, M.; Barmina, I.; Gedrovics, M.; Desnickis, A.

2007-01-01

The main aim of the study was to develop and optimise a small-scale experimental co-firing technique for the effective and clean heat energy production by replacing a proportion of fossil fuel (propane) with renewable one (wood biomass). Technical solutions of propane co-fire presenting two different ways of additional heat supply to the wood biomass are proposed and analysed. The experiments have shown that a better result can be obtained for the direct propane co-fire of the wood biomass, when the rate of wood gasification and the ignition of volatiles are controlled by additional heat energy supply to the upper portion of wood biomass. A less effective though cleaner way of heat energy production is the direct propane co-fire of volatiles when low-temperature self-sustaining burnout of the wood biomass controls the rate of the volatile formation, while additional heat energy supply to the flow of volatiles controls their burnout. The effect of propane co-fire on the heat production rate and the composition of polluting emissions is studied and analysed for different rates of the additional heat supply to the wood biomass and of the swirling air supply as well as for different charge of wood biomass above the inlet of the propane flame flow. (Authors)

Acid leaching of coal: to produce clean fuels from Turkish lignite

Energy Technology Data Exchange (ETDEWEB)

Seferinoglu, Meryem [Mineral Research and Exploration Directorate (Turkey)], email: meryem_seferinoglu66@yahoo.com; Duzenli, Derya [Ankara Central Laboratory (Turkey)

2011-07-01

With the increasing concerns about the environment, energy producers and governments are looking at developing clean energy sources. However, Turkey has limited clean energy resources and is using low grade coal which has high sulphur content as an alternative energy source. The aim of this paper is to study the possibility of generating clean fuel from Edirne Lignite and to get a better understanding of chemical mechanisms involved in coal leaching with hydrofluoric acid (HF) solutions. Leaching was conducted on Edirne Lignite with HF solution at ambient temperature and the effects of parameters such as reaction time and concentration of acid solutions on the process were evaluated. The optimum conditions were found and it was shown that ash levels can be reduced from 28.9% to 10.5% and the calorific value increased by 500kcal/kg with the HF leaching method. This study demonstrated that the production of clean fuel from high sulphur lignite is possible.

Simulation of heat exchanger network (HEN) and planning the optimum cleaning schedule

International Nuclear Information System (INIS)

Sanaye, Sepehr; Niroomand, Behzad

2007-01-01

Modeling and simulation of heat exchanger networks for estimating the amount of fouling, variations in overall heat transfer coefficient, and variations in outlet temperatures of hot and cold streams has a significant effect on production analysis. In this analysis, parameters such as the exchangers' types and arrangements, their heat transfer surface areas, mass flow rates of hot and cold streams, heat transfer coefficients and variations of fouling with time are required input data. The main goal is to find the variations of the outlet temperatures of the hot and cold streams with time to plan the optimum cleaning schedule of heat exchangers that provides the minimum operational cost or maximum amount of savings. In this paper, the simulation of heat exchanger networks is performed by choosing an asymptotic fouling function. Two main parameters in the asymptotic fouling formation model, i.e. the decay time of fouling formation (τ) and the asymptotic fouling resistance (R f ∼ ) were obtained from empirical data as input parameters to the simulation relations. These data were extracted from the technical history sheets of the Khorasan Petrochemical Plant to guaranty the consistency between our model outputs and the real operating conditions. The output results of the software program developed, including the variations with time of the outlet temperatures of the hot and cold streams, the heat transfer coefficient and the heat transfer rate in the exchangers, are presented for two case studies. Then, an objective function (operational cost) was defined, and the optimal cleaning schedule of the HEN (heat exchanger network) in the Urea and Ammonia units were found by minimizing the objective function using a numerical search method. Based on this minimization procedure, the decision was made whether a heat exchanger should be cleaned or continue to operate. The final result was the most cost effective plan for the HEN cleaning schedule. The corresponding savings by

Simulation of heat exchanger network (HEN) and planning the optimum cleaning schedule

Energy Technology Data Exchange (ETDEWEB)

Sanaye, Sepehr [Energy Systems Improvement Laboratory, Mechanical Engineering Department, Iran University of Science and Technology (IUST), Narmak, Tehran 16488 (Iran, Islamic Republic of)]. E-mail: sepehr@iust.ac.ir; Niroomand, Behzad [Energy Systems Improvement Laboratory, Mechanical Engineering Department, Iran University of Science and Technology (IUST), Narmak, Tehran 16488 (Iran, Islamic Republic of)

2007-05-15

Modeling and simulation of heat exchanger networks for estimating the amount of fouling, variations in overall heat transfer coefficient, and variations in outlet temperatures of hot and cold streams has a significant effect on production analysis. In this analysis, parameters such as the exchangers' types and arrangements, their heat transfer surface areas, mass flow rates of hot and cold streams, heat transfer coefficients and variations of fouling with time are required input data. The main goal is to find the variations of the outlet temperatures of the hot and cold streams with time to plan the optimum cleaning schedule of heat exchangers that provides the minimum operational cost or maximum amount of savings. In this paper, the simulation of heat exchanger networks is performed by choosing an asymptotic fouling function. Two main parameters in the asymptotic fouling formation model, i.e. the decay time of fouling formation ({tau}) and the asymptotic fouling resistance (R{sub f}{sup {approx}}) were obtained from empirical data as input parameters to the simulation relations. These data were extracted from the technical history sheets of the Khorasan Petrochemical Plant to guaranty the consistency between our model outputs and the real operating conditions. The output results of the software program developed, including the variations with time of the outlet temperatures of the hot and cold streams, the heat transfer coefficient and the heat transfer rate in the exchangers, are presented for two case studies. Then, an objective function (operational cost) was defined, and the optimal cleaning schedule of the HEN (heat exchanger network) in the Urea and Ammonia units were found by minimizing the objective function using a numerical search method. Based on this minimization procedure, the decision was made whether a heat exchanger should be cleaned or continue to operate. The final result was the most cost effective plan for the HEN cleaning schedule. The

Heating subsurface formations by oxidizing fuel on a fuel carrier

Science.gov (United States)

Costello, Michael; Vinegar, Harold J.

2012-10-02

A method of heating a portion of a subsurface formation includes drawing fuel on a fuel carrier through an opening formed in the formation. Oxidant is supplied to the fuel at one or more locations in the opening. The fuel is combusted with the oxidant to provide heat to the formation.

Should you get your heating ducts cleaned?

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-07-01

Canada Mortgage and Housing Corporation conducted research into duct cleaning during which time several houses were tested for hot air furnace duct performance before and after cleaning. Duct cleaning is a major industry which claims that cleaning of ducts will provide you with better indoor air quality, reduce household molds and allergens, get rid of house dust, result in more airflow and better delivery of warm air and reduce energy costs. This report does not substantiate those claims. Researchers found little or no discernible differences in the concentrations of house airborne particles or in duct airflows due to duct cleaning. This is because ducts are metal passages that cannot create dust. Most household dusts come from outdoors that has been tracked in or blows through windows and other openings. While duct cleaning may be justifiable personally, it does not change the quality of the air you breathe, nor will it significantly affect airflow or heating costs. Some filters effectively clean the air in the ducts but they do not create a dust-free environment because of the above-mentioned dust sources. The only time that duct cleaning may make sense is if you have water in your ducts that can result in mold growth, if you are moving into a newly constructed house to remove drywall dust, if your are having trouble with furnace airflow, or if you see an accumulation of debris in the return air ducts. It was emphasized that broadcast spraying of biocides within the duct system should not be performed.

Development of a hot heat exchanger and a cleaning system for a 35 kW hermetic four cylinder Stirling engine for solid biomass fuels

DEFF Research Database (Denmark)

Carlsen, Henrik; Marinitsch, Gerald; Schöch, Martin

2005-01-01

been operated for more than 9,000 hours. Operating experiences gained from these plants formed the basis for the further development of this technology. The experiences showed that the efficiency of the Stirling hot gas heat exchanger and of the hot gas heat exchanger cleaning system have to be further...... optimised. Within the scope of a RD&D project, a new hot gas heat exchanger and a new cleaning system have been developed and optimised in cooperation of the AUSTRIAN BIOENERGY CENTRE GmbH, the Technical University of Denmark, MAWERA Holzfeuerungsanlagen GmbH, Austria, and BIOS BIOENERGIESYSTEME Gmb......H, Austria. The new design of the Stirling hot gas heat exchanger has been developed in order to optimise the performance of the engine and simplify the geometry. In this respect, an equal distribution of the heat transfer across each tube in the hot gas heat exchanger, the reduction of the internal Helium...

Alternative Fuels and Advanced Vehicles: Resources for Fleet Managers (Clean Cities) (Presentation)

Energy Technology Data Exchange (ETDEWEB)

Brennan, A.

2011-04-01

A discussion of the tools and resources on the Clean Cities, Alternative Fuels and Advanced Vehicles Data Center, and the FuelEconomy.gov Web sites that can help vehicle fleet managers make informed decisions about implementing strategies to reduce gasoline and diesel fuel use.

Problems of cleaning of gas releases from heat generating facilities

International Nuclear Information System (INIS)

Tret'yakov, V.; Burdejnaya, T.

2000-01-01

The paper deals with the problem of flue gases cleaning in the situation of a significant increasing use of fossil fuels in the Russian energy production. Information is given about the methods used in TPPs in different countries for cleaning of the gases released to the atmosphere from SO 2 and NO x . The main ways for solving the problem of decreasing of air pollution are outlined

The local implementation of clean(er) fuels policies in Europe. A Handbook with guidelines. Final version

International Nuclear Information System (INIS)

Mulder, F.; Amara, Sliman Abu; Uustal, M.; Pelkmans, L.; Devriendt, N.; Rogulska, M.; Defranceschi, P.

2009-05-01

This handbook aims to guide the local/regional governments all over Europe who are involved in implementing clean(er) fuel policies in transport. The general challenge these governments are facing is how local policies on clean(er) fuels and vehicles can be made operational. Hence, how can the step be made from a vision on the strategic policy level, to a vision on the implementation of these policies. A local/regional policy on clean(er) fuels and vehicles is commonly part of the larger category 'sustainable transport policy', which in itself is part of a broader local environmental policy. The encompassing local/regional sustainable mobility policy will in most cases be based on the three well known main policy aims in this area: CO2 reduction; Improving the local air quality; and Improving the security of supply (locally often less stressed). This handbook will focus on the actual implementation of a clean(er) fuels and vehicles policy. It will describe the main challenges and how these can be overcome. It will describe how the market conditions for clean(er) fuels and vehicles can be created by establishing the vital market elements and which process is required to do so. And it will show how local enterprises can be involved and what the role of the local governments in this process can be. In order to identify the local success factors in overcoming the main challenges for implementation, case studies have been carried out in three European cities, namely Stockholm (Sweden), Graz (Austria) and Lille (France). The choice of these cities was based on their successes in implementing clean(er) fuel policies (although they followed different paths) and the fact that they managed to achieve ambitious clean(er) fuel/ clean(er) vehicle targets. These cities may thus be considered as ?good practice examples?. The case studies are based on existing literature, on multiple stakeholders? interviews in all three cities, and on two small surveys. The objectives of this

Study of fuel cell powerplant with heat recovery

Science.gov (United States)

King, J. M.; Grasso, A. P.; Clausi, J. V.

1975-01-01

It was shown that heat can be recovered from fuel cell power plants by replacing the air-cooled heat exchangers in present designs with units which transfer the heat to the integrated utility system. Energy availability for a 40-kW power plant was studied and showed that the total usable energy at rated power represents 84 percent of the fuel lower heating value. The effects of design variables on heat availability proved to be small. Design requirements were established for the heat recovery heat exchangers, including measurement of the characteristics of two candidate fuel cell coolants after exposure to fuel cell operating conditions. A heat exchanger test program was defined to assess fouling and other characteristics of fuel cell heat exchangers needed to confirm heat exchanger designs for heat recovery.

Combustion and environmental performance of clean coal end products

Energy Technology Data Exchange (ETDEWEB)

Skodras, G.; Sakellaropoulos, G. [Centre for Research and Technology, Hellas, Ptolemaidas-Kozanis, Ptolemaida (Greece). Inst. for Solid Fuel Technolgy and Applications]|[Aristotle Univ. of Thessaloniki, Thessaloniki (Greece). Dept. of Chemical Engineering, Chemical Process Engineering Lab]|[Chemical Process Engineering Research Inst., Thessaloniki (Greece). Lab. of Solid Fuels and Environment; Someus, E. [Thermal Desorption Technology Group (Greece); Grammelis, P.; Amarantos, P.S. [Centre for Research and Technology, Hellas, Ptolemaidas-Kozanis, Ptolemaida (Greece). Inst. for Solid Fuel Technolgy and Applications; Palladas, A.; Basinas, P.; Natas, P.; Prokopidou, M.; Diamantopoulou, I.; Sakellaropoulos, G. [Aristotle Univ. of Thessaloniki, Thessaloniki (Greece). Dept. of Chemical Engineering, Chemical Process Engineering Lab

2006-07-01

Clean and affordable power production is needed in order to achieve sustainable economic development. This paper focused on clean coal technologies in which coal-fired power plants are used in conjunction with large amounts of renewable energy sources to offer a high level of process safety and long term management of all residual operation streams. Thermal Desorption Recycle-Reduce-Reuse Technology (TDT-3R) was described as being a promising solid fuel pretreatment process for clean energy production up to 300 MWe capacities. TDT-3R is based on low temperature carbonisation fuel pre-treatment principles, which produce cleansed anthracite type fuels from coal and other carbonaceous material such as biomass and organic wastes. The combustion efficiency of such clean coals and the environmental performance of the TDT-3R process were investigated in this study via pilot scale tests of clean fuel production. Tests included flue gas emissions monitoring, raw fuel and product characterisation and thermogravimetric tests, polychlorinated dibenzo-p-dioxins and dibenzo-furans, and heavy metals analyses, and toxicity tests. Raw material included coal and biomass, such as willow, straw and demolition wood. The fuels were heated in a rotary kiln operating at 550 degrees C under slightly vacuum conditions. Clean coals were tested either alone or in conjunction with biomass fuels in a pilot scale combustion facility at Dresden, Germany. The clean coal samples were shown to have higher fixed carbon and ash content and lower volatiles compared to the respective raw coal samples. The major advantage of the TDT-3R process is the production of fuels with much lower pollutants content. Low nitrogen, sulphur, chlorine and heavy metal contents result in produced fuels that have excellent environmental performance, allow boiler operation in higher temperatures and overall better efficiency. Moreover, the use of clean fuels reduces deposition problems in the combustion chamber due to the

Continuous cleaning of heat exchanger with recirculating fluidized bed

International Nuclear Information System (INIS)

St Kollbach, J.; Dahm, W.; Rautenbach, R.

1987-01-01

Fluidized bed heat exchangers for liquids have been studied in the United States, the Netherlands, and the Federal Republic of Germany. Between 1965 and 1970, fluidized bed heat exchangers were developed in the United States as brine heaters in seawater desalination. Furthermore, their potential in the utilization of geothermal energy was tested between 1975 and 1980. In the Netherlands, fluidized bed heat exchangers have been developed since 1973 for brine heating and heat recovery in multistage flash evaporators for seawater desalination and, since about 1980, for applications in the process industry. The authors became interested in fluidized bed heat exchangers first in 1978 in connection with wastewater evaporation. The authors emphasize that the results of all these groups were in basic agreement. They can be summarized as follows: 1. The fluidized bed will in many cases maintain totally clean surfaces and neither scaling nor fouling will occur. In cases where even a fluidized bed cannot completely prevent scaling or fouling, the thickness of the layer is controlled. In these cases stable operation maintaining acceptable overall heat transfer coefficients is possible without cleaning. 2. There are always excellent heat transfer coefficients as low superficial velocities of less than ν < 0.5 m/s. 3. The pressure losses are comparable with those in normal heat exchangers since fluidized bed heat exchangers are mostly operated at low superficial velocities. 4. Feed flow may be varied between 50 and 150% or more of the design feed flow. 5. Erosion is negligible. 6. Fluidized bed particles can be manufactured from all sorts of chemically and mechanically resistant materials, such as sand, glass, ceramics, and metals

Ex-core fuel damage event at paks causes, consequences and lessons learned

International Nuclear Information System (INIS)

Bajsz, J.; Gado, J.

2004-01-01

On April 10, 2003 Paks NPP experienced a loss of decay-heat removal to 30 irradiated fuel assemblies undergoing a cleaning process in a fuel service pit near the unit 2 spent fuel pool. Following chemical cleaning of high decay-heat fuel, a delay in removing the cleaning vessel's lid left the cleaning system in such a condition that did not provide adequate cooling to the fuel. After several hours of the fuel being under-cooled, a steam bubble developed in the vessel, essentially uncovering the fuel. When the lid of the vessel was removed, the sudden introduction of cool water thermally shocked the fuel causing significant structural damage and a release of fission product gases to the reactor building. The paper will discuss the causes of the event as well as the contributing factors to it. Detailed information will be given about the planning and preparation of the recovery actions. The in-depth analyses of the consequences and lessons learned complete the lecture. (author)

Harnessing Solar Energy for the Production of Clean Fuel

NARCIS (Netherlands)

Pandit, A.; Holzwarth, A.; de Groot, H.J.M.

2008-01-01

The European Union and its member states are being urged by leading scientists to make a major multi million Euro commitment to solar driven production of environmentally clean electricity, hydrogen and other fuels, as the only sustainable long-term solution for global energy needs. The most

Cleaning and disinfection of heat exchangers; Reinigung und Desinfektion von Waermeuebertragern

Energy Technology Data Exchange (ETDEWEB)

Kaup, Christoph [HOWATHERM Klimatechnik GmbH, Bruecken (Germany)

2008-03-15

Since the introduction of VDI 6022 high demands are made on the hygiene of RLT devices. In order to ensure the hygiene in the devices, regular cleaning cycles are necessary and to be kept. In particular, a question is put on the suitable cleaning method in the case of finned heat exchanger.

Ultra-Clean Fischer-Tropsch Fuels Production and Demonstration Project

Energy Technology Data Exchange (ETDEWEB)

Steve Bergin

2005-10-14

The Report Abstract provides summaries of the past year's activities relating to each of the main project objectives. Some of the objectives will be expanded on in greater detail further down in the report. The following objectives have their own addition sections in the report: Dynamometer Durability Testing, the Denali Bus Fleet Demonstration, Bus Fleet Demonstrations Emissions Analysis, Impact of SFP Fuel on Engine Performance, Emissions Analysis, Feasibility Study of SFPs for Rural Alaska, and Cold Weather Testing of Ultra Clean Fuel.

C1 CHEMISTRY FOR THE PRODUCTION OF ULTRA-CLEAN LIQUID TRANSPORTATION FUELS AND HYDROGEN

Energy Technology Data Exchange (ETDEWEB)

Gerald P. Huffman

2004-09-30

The Consortium for Fossil Fuel Science (CFFS) is a research consortium with participants from the University of Kentucky, University of Pittsburgh, West Virginia University, University of Utah, and Auburn University. The CFFS is conducting a research program to develop C1 chemistry technology for the production of clean transportation fuel from resources such as coal and natural gas, which are more plentiful domestically than petroleum. The processes under development will convert feedstocks containing one carbon atom per molecular unit into ultra clean liquid transportation fuels (gasoline, diesel, and jet fuel) and hydrogen, which many believe will be the transportation fuel of the future. Feedstocks include synthesis gas, a mixture of carbon monoxide and hydrogen produced by coal gasification, coalbed methane, light products produced by Fischer-Tropsch (FT) synthesis, methanol, and natural gas.

Development of OTM Syngas Process and Testing of Syngas Derived Ultra-clean Fuels in Diesel Engines and Fuel Cells

Energy Technology Data Exchange (ETDEWEB)

E.T. Robinson; John Sirman; Prasad Apte; Xingun Gui; Tytus R. Bulicz; Dan Corgard; John Hemmings

2005-05-01

This final report summarizes work accomplished in the Program from January 1, 2001 through December 31, 2004. Most of the key technical objectives for this program were achieved. A breakthrough material system has lead to the development of an OTM (oxygen transport membrane) compact planar reactor design capable of producing either syngas or hydrogen. The planar reactor shows significant advantages in thermal efficiency and a step change reduction in costs compared to either autothermal reforming or steam methane reforming with CO{sub 2} recovery. Syngas derived ultra-clean transportation fuels were tested in the Nuvera fuel cell modular pressurized reactor and in International Truck and Engine single cylinder test engines. The studies compared emission and engine performance of conventional base fuels to various formulations of ultra-clean gasoline or diesel fuels. A proprietary BP oxygenate showed significant advantage in both applications for reducing emissions with minimal impact on performance. In addition, a study to evaluate new fuel formulations for an HCCI engine was completed.

Ninth international conference on CANDU fuel, 'fuelling a clean future'

International Nuclear Information System (INIS)

2005-01-01

The Canadian Nuclear Society's 9th International Conference on CANDU fuel took place in Belleville, Ontario on September 18-21, 2005. The theme for this year's conference was 'Fuelling a Clean Future' bringing together over 80 delegates ranging from: designers, engineers, manufacturers, researchers, modellers, safety specialists and managers to share the wealth of their knowledge and experience. This international event took place at an important turning point of the CANDU technology when new fuel design is being developed for commercial application, the Advanced CANDU Reactor is being considered for projects and nuclear power is enjoying a renaissance as the source energy for our future. Most of the conference was devoted to the presentation of technical papers in four parallel sessions. The topics of these sessions were: Design and Development; Fuel Safety; Fuel Modelling; Fuel Performance; Fuel Manufacturing; Fuel Management; Thermalhydraulics; and, Spent Fuel Management and Criticalty

Clean fuel technologies and clean and reliable energy: a summary

International Nuclear Information System (INIS)

Bulatov, Igor; Klemes, Jiri Jaromir

2011-01-01

There are two major areas covered by this current Special Issue: Cleaner Fuel Technologies and Waste Processing. In addition, the Special Issue, also includes some recent developments in various fields of energy efficiency research. The first group of contributions considers in detail, hydrogen production from biomass and hydrogen production by the sorption-enhanced steam methane reforming process (SE-SMR). Biomass-related technologies are also discussed for a design of an integrated biorefinery, production of clean diesel fuel by co-hydrogenation of vegetable oil with gas oil and utilization of microwave and ultrasound pretreatments in the production of bioethanol from corn. Waste Processing aspects are considered in the second group of papers. This section includes integrated waste-to-energy plants, utilisation of municipal solid waste in the cement industry and urban supply and disposal systems. The third topic is intentionally made rather loose: it includes different research topics on various aspects of energy efficiency, e.g. resource-saving network design, new research on divided wall columns, vehicle logistics as process-network synthesis for energy consumption and CO 2 reduction.

Fuel cycles and fission products clean up for the MOSART concept

Energy Technology Data Exchange (ETDEWEB)

Ignatiev, V. V.; Feynberg, O. S.; Zakirov, R. Y. [Russian Research Center, Kurchatov Institute, Moscow (Russian Federation)

2008-08-15

Analysis of different methods for MOSART fuel salt clean up and experimental results produced within ISTC 1606 permits to make the following conclusions: {center_dot} Fuel salt clean up steps of Li,Be/F MOSART system could be based on the method of reductive extraction in liquid bismuth. {center_dot} Electrodeposition on solid indifferent electrodes (Mo, W) is not effective for separation of actinides and lanthanides in Li,Na,Be/F melt. However, preliminary experiments on electrodeposition on solid non indifferent electrodes (nickel) give foundation to suppose that An/Ln separation on these electrodes could be more effective. In order to determine characteristics of An/Ln electrochemical separation, it is necessary to conduct additional studies in Li,Na,Be/F melt on solid non indifferent electrodes.

Soybean-derived biofuels and home heating fuels.

Science.gov (United States)

Mushrush, George W; Wynne, James H; Willauer, Heather D; Lloyd, Christopher L

2006-01-01

It is environmentally enticing to consider replacing or blending petroleum derived heating fuels with biofuels for many reasons. Major considerations include the soaring worldwide price of petroleum products, especially home heating oil, the toxicity of the petroleum-derived fuels and the environmental damage that leaking petroleum tanks afford. For these reasons, it has been suggested that domestic renewable energy sources be considered as replacements, or at the least, as blending stocks for home heating fuels. If recycled soy restaurant cooking oils could be employed for this purpose, this would represent an environmental advantage. Renewable plant sources of energy tend to be less toxic than their petroleum counterparts. This is an important consideration when tank leakage occurs. Home fuel oil storage tanks practically always contain some bottom water. This water environment has a pH value that factors into heating fuel stability. Therefore, the question is: would the biofuel help or exacerbate fuel stability and furnace maintenance issues?

Coal-water fuels - a clean coal solution for Eastern Europe

International Nuclear Information System (INIS)

Ljubicic, B.; Willson, W.; Bukurov, Z.; Cvijanovic, P.; Stajner, K.; Popovic, R.

1993-01-01

Eastern Europe currently faces great economic and environmental problems. Among these problems is energy provision. Coal reserves are large but cause pollution while oil and gas need to be used for export. Formal 'clean coal technologies' are simply too expensive to be implemented on a large scale in the current economic crisis. The promised western investment and technological help has simply not taken place, western Europe must help eastern Europe with coal technology. The cheapest such technology is coal-water fuel slurry. It can substitute for oil, but research has not been carried out because of low oil prices. Coal-water fuel is one of the best methods of exploiting low rank coal. Many eastern European low rank coals have a low sulfur content, and thus make a good basis for a clean fuel. Italy and Russia are involved in such a venture, the slurry being transported in a pipeline. This technology would enable Russia to exploit Arctic coal reserves, thus freeing oil and gas for export. In Serbia the exploitation of sub-Danube lignite deposits with dredging mining produced a slurry. This led to the use and development of hot water drying, which enabled the removal of many of the salts which cause problems in pulverized fuel combustion. The system is economic, the fuel safer to transport then oil, either by rail or in pipelines. Many eastern European oil facilities could switch. 24 refs

Heat planning for fossil-fuel-free district heating areas with extensive end-use heat savings

DEFF Research Database (Denmark)

Harrestrup, Maria; Svendsen, S.

2014-01-01

is a theoretical investigation of the district heating system in the Copenhagen area, in which heat conservation is related to the heat supply in buildings from an economic perspective. Supplying the existing building stock from low-temperature energy resources, e.g. geothermal heat, might lead to oversized......The Danish government plans to make the Danish energy system to be completely free of fossil fuels by 2050 and that by 2035 the energy supply for buildings and electricity should be entirely based on renewable energy sources. To become independent from fossil fuels, it is necessary to reduce...... the energy consumption of the existing building stock, increase energy efficiency, and convert the present heat supply from fossil fuels to renewable energy sources. District heating is a sustainable way of providing space heating and domestic hot water to buildings in densely populated areas. This paper...

Biomass gasification--a substitute to fossil fuel for heat application

International Nuclear Information System (INIS)

Dasappa, S.; Sridhar, H.V.; Sridhar, G.; Paul, P.J.; Mukunda, H.S.

2003-01-01

The paper addresses case studies of a low temperature and a high temperature industrial heat requirement being met using biomass gasification. The gasification system for these applications consists of an open top down draft reburn reactor lined with ceramic. Necessary cooling and cleaning systems are incorporated in the package to meet the end use requirements. The other elements included are the fuel conveyor, water treatment plant for recirculating the cooling water and adequate automation to start, shut down and control the operations of the gasifier system. Drying of marigold flower, a low temperature application is considered to replace diesel fuel in the range of 125-150 l h -1 . Gas from the 500 kg h -1 , gasifier system is piped into the producer gas burners fixed in the combustion chamber with the downstream process similar to the diesel burner. The high temperature application is for a heat treatment furnace in the temperature range of 873-1200 K. A 300 kg h -1 of biomass gasifier replaces 2000 l of diesel or LDO per day completely. The novelty of this package is the use of one gasifier to energize 16 burners in the 8 furnaces with different temperature requirements. The system operates over 140 h per week on a nearly nonstop mode and over 4000 h of operation replacing fossil fuel completely. The advantage of bioenergy package towards the economic and environmental considerations is presented

IAEA expert review mission completes assessment of fuel cleaning incident at Paks Nuclear Power Plant

International Nuclear Information System (INIS)

2003-01-01

Full text: The IAEA today completed its expert review mission to investigate the 10 April fuel cleaning incident at the Paks nuclear power plant in Hungary. The mission was requested by the Hungarian Government to provide an independent assessment of the causes and actions taken by the plant and Hungarian authorities. The team was composed of nuclear and radiation experts from the IAEA, Austria, Canada, Finland, Slovakia, the United Kingdom and the United States. In a press conference, team leader Miroslav Lipar highlighted the team's findings in five areas: On management, the team concluded that the Hungarian Atomic Energy Authority and Paks are committed to improving the safety of the plant. They noted that as a result of steam generator decontamination in previous years, deposits became attached to the fuel assemblies. A decision was made to clean the fuel and contract an outside company to develop and operate a fuel cleaning process. The team found that the design and operation of the fuel cleaning tank and system was not accomplished in the manner prescribed by the IAEA Safety Standards. Neither the Hungarian Atomic Energy Authority nor Paks used conservative decision-making in their safety assessments for this unproven fuel cleaning system. The team determined that there was an over-reliance on the contractor that had been selected for the design, management and operation of the fuel cleaning system. Time pressure related to a prescribed fuel outage schedule, combined with confidence generated by previous successful fuel cleaning operations, contributed to a weak assessment of a new design and operation, which involved fuel directly removed from the reactor following a planned shutdown. On regulatory oversight, the IAEA team concluded that the Hungarian Atomic Energy Authority underestimated the safety significance of the proposed designs for the fuel cleaning system, which resulted in a less than rigorous review and assessment than should have been necessary

Solid oxide fuel cells for transportation: A clean, efficient alternative for propulsion

International Nuclear Information System (INIS)

Kumar, R.; Krumpelt, M.; Myles, K.M.

1993-01-01

Fuel cells show great promise for providing clean and efficient transportation power. Of the fuel cell propulsion systems under investigation, the solid oxide fuel cell (SOFC) is particularly attractive for heavy duty transportation applications that have a relatively long duty cycle, such as locomotives, trucks, and barges. Advantages of the SOFC include a simple, compact system configuration; inherent fuel flexibility for hydrocarbon and alternative fuels; and minimal water management. The specific advantages of the SOFC for powering a railroad locomotive are examined. Feasibility, practicality, and safety concerns regarding SOFCs in transportation applications are discussed, as am the major R ampersand D issues

Processes of elimination of activated corrosion products. Chemical decontamination - fuel cleaning

International Nuclear Information System (INIS)

Viala, C.; Brun, C.; Neuhaus, R.; Richier, S.; Bachet, M.

2007-01-01

The abatement of the individual and collective dose of a PWR imposes to control the source term through different processes implemented during the plant exploitation. When the limits of these different optimization processes are reached, the abatement of dose rates requires the implementation of curative processes. The objective is thus to eliminate the contaminated oxides and deposits present on surfaces free of radiation flux, and eventually on surfaces under radiation flux and on the fuel itself. The chemical decontamination of equipments and systems is the main and universal remedy implemented at different levels. On the other hand, the ultrasonic cleaning of fuel assemblies is a promising process. This paper aims at illustrating these different techniques using concrete examples of application in France and abroad (decontamination during steam generator replacement, decontamination of primary pump scroll in hot workshop, decontamination of loop sections, ultrasonic cleaning of fuel). The description of these different operations stresses on their efficiency in terms of dosimetric gain, duration of implementation, generation of wastes, and recontamination following their implementation. (J.S.)

Alternative Fuel News: Official Publication of the Clean Cities Network and the Alternative Fuels Data Center, Vol. 5, No. 3

Energy Technology Data Exchange (ETDEWEB)

2001-11-01

A quarterly magazine with articles on alternative fuel school buses, the market growth of biodiesel fuel, National AFV Day 2002, model year 2002 alternative fuel passenger cars and light trucks, the Michelin Challenge Bibendum road rally, and advanced technology vehicles at Robins Air Force Base, the Top Ten Clean Cities coalitions for 2000, and AFVs on college campuses.

Fossil fuels. Commercializing clean coal technologies

International Nuclear Information System (INIS)

Fultz, Keith O.; Sprague, John W.; Kirk, Roy J.; Clark, Marcus R. Jr.; Greene, Richard M.; Buncher, Carole S.; Kleigleng, Robert G.; Imbrogno, Frank W.

1989-03-01

Coal, an abundant domestic energy source, provides 25 percent of the nation's energy needs, but its use contributes to various types of pollution, including acid rain. The Department of Energy (DOE) has a Clean Coal Technology (CCT) program whose goal is to expand the use of coal in an environmentally safe manner by contributing to the cost of projects demonstrating the commercial applications of emerging clean coal technologies. Concerned about the implementation of the CCT program, the Chairman, Subcommittee on Energy and Power, House Committee on Energy and Commerce, requested GAO to report on (1) DOE's process of negotiating cooperative agreements with project sponsors, (2) changes DOE has made to the program, (3) the status of funded projects, and (4) the interrelationship between acid rain control proposals and the potential commercialization of clean coal technologies. Under the CCT program, DOE funds up to 50 percent of the cost of financing projects that demonstrate commercial applications of emerging clean coal technologies. DOE has conducted two solicitations for demonstration project proposals and is planning a third solicitation by May 1989. The Congress has appropriated $400 million for the first solicitation, or round one of the program, $575 million for round two, and $575 million for round three, for a total of $1.55 billion. For the round-one solicitation, DOE received 51 proposals from project sponsors. As of December 31, 1988, DOE had funded nine projects and was in the process of negotiating cooperative financial assistance agreements with sponsors of four projects. In September 1988, DOE selected 16 round-two projects from 55 proposals submitted and began the process of negotiating cooperative agreements with the project sponsors. The Congress has debated the need to reduce acid rain-causing emissions associated with fossil fuel combustion. The 100th Congress considered but did not enact about 20 acid rain control bills. On February 9, 1989

Biomass gasification for CHP with dry gas cleaning and regenerative heat recovery

Energy Technology Data Exchange (ETDEWEB)

NONE

2002-05-01

Small scale CHP plants based on biomass gasification technologies are generally expensive and not very efficient due to gas quality problems which increase operation and maintenance cost as well as breakdown. To overcome this situation the team has developed, integrated and tested a complete biomass gasification combine heat and power prototype plant of 250 kWth equipped with a specifically developed dry gas cleaning and heat recovery system. The dry gas cleaning device is a simple dry gas regenerative heat exchanger where tars are stopped by condensation but working at a temperature above due point in order to avoid water condensation. Two types of heat particles separation devices have been tested in parallel multi-cyclone and ceramic filters. After several month spent on modelling design, construction and optimisation, a full test campaign of 400 hours continuous monitoring has been done where all working parameters has been monitored and gas cleaning device performances has been assessed. Results have shown: Inappropriateness of the ceramic filters for the small scale unit due to operation cost and too high sensibility of the filters to the operation conditions fluctuating in a wide range, despite a very high particle separation efficiency 99 %; Rather good efficiency of the multi-cyclone 72% but not sufficient for engine safety. Additional conventional filters where necessary for the finest part; Inappropriateness of the dry gas heat exchanger device for tar removal partly due to a low tar content of the syngas generated, below 100 mg/Nm{sup 3} , but also due to their composition which would have imposed, to be really efficient, a theoretical condensing temperature of 89 C below the water condensation temperature. These results have been confirmed by laboratory tests and modelling. However the tar cracking phase have shown very interesting results and proved the feasibility of thermal cracking with full cleaning of the heat exchanger without further mechanical

Fuel-to-cladding heat transfer coefficient into reactor fuel element

International Nuclear Information System (INIS)

Lassmann, K.

1979-01-01

Models describing the fuel-to-cladding heat transfer coefficient in a reactor fuel element are reviewed critically. A new model is developed with contributions from solid, fluid and radiation heat transfer components. It provides a consistent description of the transition from an open gap to the contact case. Model parameters are easily available and highly independent of different combinations of material surfaces. There are no restrictions for fast transients. The model parameters are fitted to 388 data points under reactor conditions. For model verification another 274 data points of steel-steel and aluminium-aluminium interfaces, respectively, were used. The fluid component takes into account peak-to-peak surface roughnesses and, approximatively, also the wavelengths of surface roughnesses. For minor surface roughnesses normally prevailing in reactor fuel elements the model asymptotically yields Ross' and Stoute's model for the open gap, which is thus confirmed. Experimental contact data can be interpreted in very different ways. The new model differs greatly from Ross' and Stoute's contact term and results in better correlation coefficients. The numerical algorithm provides an adequate representation for calculating the fuel-to-cladding heat transfer coefficient in large fuel element structural analysis computer systems. (orig.) [de

Fuel-clad heat transfer coefficient of a defected fuel rod

International Nuclear Information System (INIS)

Bruet, M.; Stora, J.P.

1976-01-01

A special rod has been built with a stack of UO 2 pellets inside a thick zircaloy clad. The atmosphere inside the fuel rod can be changed and particularly the introduction of water is possible. The capsule was inserted in the Siloe pool reactor in a special device equipped with a neutron flux monitor. The fuel centerline temperature and the temperature at a certain radius of the clad were recorded by two thermocouples. The temperature profiles in the fuel and in the cladding have been calculated and then the heat transfer coefficient. In order to check the proper functioning of the device, two runs were successively achieved with a helium atmosphere. Then the helium atmosphere inside the fuel rod was removed and replaced by water. The heat transfer coefficients derived from the measurements at low power level are in agreement with the values given by the model based on thermal conductivity. However, for higher power levels, the heat transfer coefficients become higher than those based on the calculated gap

Ultra-clean Fischer-Tropsch (F-T) Fuels Production and Demonstration Project

Energy Technology Data Exchange (ETDEWEB)

Stephen P. Bergin

2006-06-30

The objective of the DOE-NETL Fischer-Tropsch (F-T) Production and Demonstration Program was to produce and evaluate F-T fuel derived from domestic natural gas. The project had two primary phases: (1) fuel production of ultra-clean diesel transportation fuels from domestic fossil resources; and (2) demonstration and performance testing of these fuels in engines. The project also included a well-to-wheels economic analysis and a feasibility study of small-footprint F-T plants (SFPs) for remote locations such as rural Alaska. During the fuel production phase, ICRC partnered and cost-shared with Syntroleum Corporation to complete the mechanical design, construction, and operation of a modular SFP that converts natural gas, via F-T and hydro-processing reactions, into hydrogensaturated diesel fuel. Construction of the Tulsa, Oklahoma plant started in August 2002 and culminated in the production of over 100,000 gallons of F-T diesel fuel (S-2) through 2004, specifically for this project. That fuel formed the basis of extensive demonstrations and evaluations that followed. The ultra-clean F-T fuels produced had virtually no sulfur (less than 1 ppm) and were of the highest quality in terms of ignition quality, saturation content, backend volatility, etc. Lubricity concerns were investigated to verify that commercially available lubricity additive treatment would be adequate to protect fuel injection system components. In the fuel demonstration and testing phase, two separate bus fleets were utilized. The Washington DC Metropolitan Area Transit Authority (WMATA) and Denali National Park bus fleets were used because they represented nearly opposite ends of several spectra, including: climate, topography, engine load factor, mean distance between stops, and composition of normally used conventional diesel fuel. Fuel evaluations in addition to bus fleet demonstrations included: bus fleet emission measurements; F-T fuel cold weather performance; controlled engine dynamometer

Alternative Fuel News: Official Publication of the Clean Cities Network and the Alternative Fuels Data Center, Vol. 4, No. 2

Energy Technology Data Exchange (ETDEWEB)

Ficker, C.

2000-09-08

This issue of Alternative Fuel News discusses Executive Order 13149 which is designed to not only increase the use of alternative fuel by federal agencies but also to increase the use of fuel efficient vehicles in the federal fleet. Also highlighted is the 6th National Clean Cities Conference and Expo held in San Diego, May 7-10, 2000, which attracted nearly 1,000 people for three action-packed days of alternative fuel activities. The work to develop a market for alternative fuels is more important than ever.

Sodium removal of fuel elements by vacuum distillation

International Nuclear Information System (INIS)

Buescher, E.; Haubold, W.; Jansing, W.; Kirchner, G.

1978-01-01

Cleaning of sodium-wetted core components can be performed by using either lead, moist nitrogen, or alcohol. The advantages of these methods for cleaning fuel elements without causing damage are well known. The disadvantage is that large amounts of radioactive liquids are formed during handling in the latter two cases. In this paper a new method to clean components is described. The main idea is to remove all liquid metal from the core components within a comparatively short period of time. Fuel elements removed from the reactor must be cooled because of high decay heat release. To date, vacuum distillation of fuel elements has not yet been applied

Alternative Fuel News, Vol. 3 No. 3

Energy Technology Data Exchange (ETDEWEB)

Clean Cities Program at DOE

1999-10-29

The alternative fuel industry is heating up. It is a very exciting time to be in the energy business, especially when it comes to transportation. Celebrating of the milestone 75th Clean Cities coalition and kick off of the new Federal Alternative Fuel Vehicle (AFV) USER Program is occurring in cities across the country. Clean Energy for the 21st Century and the events that are happening during Energy Awareness Month are covered in this issue. Spotlighted are niche markets; several airports across the country are successfully incorporating alternative fuels into their daily routines.

Residual heat use generated by a 12 kW fuel cell in an electric vehicle heating system

International Nuclear Information System (INIS)

Colmenar-Santos, Antonio; Alberdi-Jiménez, Lucía; Nasarre-Cortés, Lorenzo; Mora-Larramona, Joaquín

2014-01-01

A diesel or gasoline vehicle heating is produced by the heat of the engine coolant liquid. Nevertheless, electric vehicles, due to the fact that electric motor transform directly electricity into mechanical energy through electromagnetic interactions, do not generate this heat so other method of providing it has to be developed. This study introduces the system developed in a fuel cell electric vehicle (lithium-ion battery – fuel cell) with residual heat use. The fuel cell electric vehicle is driven by a 12 kW PEM (proton exchange membrane) fuel cell. This fuel cell has an operating temperature around 50 °C. The residual heat generated was originally wasted by interaction with the environment. The new developed heating system designed integrates the heat generated by the fuel cell into the heating system of the vehicle, reducing the global energy consumption and improving the global efficiency as well. - Highlights: • Modification of heating system was done by introducing the residual heat from fuel cell. • Maximum heat achieved by the heating radiator of 9.27 kW. • Reduction of the heat dissipation by the fuel cell cooling system 1.5 kW. • Total efficiency improvement of 20% with an autonomy increase of 21 km

Bio diesel- the Clean, Green Fuel for Diesel Engines

International Nuclear Information System (INIS)

Elkareish, S.M.M.

2004-01-01

Natural, renewable resources such as vegetable oils, animal fats and recycled restaurant greases can be chemically transformed into clean burning bio diesel fuels (1). Just like petroleum diesel, bio diesel operates in combustion-ignition engines. Blends of up to 20% bio diesel (mixed with petroleum diesel fuels) can be used in nearly all diesel equipment and are compatible with most storage and distribution equipment. Using bio diesel in a conventional diesel engine substantially reduces emissions of unburned hydrocarbons, carbon monoxide, sulphates, polycyclic aromatic hydrocarbons, nitrated polycyclic aromatic hydrocarbons, and particulate matter. The use of bio diesel has grown dramatically during the last few years. Egypt has a promising experiment in promoting forestation by cultivation of Jatropha plant especially in luxor and many other sites of the country. The first production of the Egyptian Jatropha seeds oil is now under evaluation to produce a cost-competitive bio diesel fuel

Cancer-risk benefits of clean fuel technology and policy. A statistical analysis

Energy Technology Data Exchange (ETDEWEB)

Gallagher, Paul [Economics Department, 481 Heady Hall, Iowa State University, Ames, IA 50011 (United States); Lazarus, William [Applied Economics Department, 253 COB, University of Minnesota, St. Paul, MN 55455 (United States); Shapouri, Hosein; Conway, Roger; Duffield, James [Office of Energy Policy and New Uses, 400 Independence Avenue, SW Rm. 4059 So. Bldg, United States Department of Agriculture, WA, DC 20250 (United States)

2009-12-15

The hypothesis of this study is that there is a statistical relationship between the lung cancer mortality rate and the intensity of fuel consumption (measured in gallons/square mile) at a particular location. We estimate cross-section regressions of the mortality rate due to lung cancer against the intensity of fuel consumption using local data for the entire US, before the US Clean Air Act (CAA) in 1974 and after the most recent policy revisions in 2004. The cancer rate improvement estimate suggests that up to 10 lung cancer deaths per 100,000 residents are avoided in the largest urban areas with highest fuel consumption per square mile. In New York City, for instance, the mortality reduction may be worth about USD 5.7 billion annually. Across the US, the estimated value of statistical life (VSL) benefit is USD 27.2 billion annually. There are likely three inseparable reasons that contributed importantly to this welfare improvement. First, the CAA regulations mandated reduction in specific carcinogenic chemicals or smog components. Second, technologies such as the catalytic converter (CC) and low-particulate diesel engine were adopted. Third, biofuels have had important roles, making the adoption of clean air technology possible and substituting for high emission fuels. (author)

Cancer-risk benefits of clean fuel technology and policy: A statistical analysis

Energy Technology Data Exchange (ETDEWEB)

Gallagher, Paul, E-mail: paulg@iastate.ed [Economics Department, 481 Heady Hall, Iowa State University, Ames, IA 50011 (United States); Lazarus, William [Applied Economics Department, 253 COB, University of Minnesota, St. Paul, MN 55455 (United States); Shapouri, Hosein; Conway, Roger; Duffield, James [Office of Energy Policy and New Uses, 400 Independence Avenue, SW (Rm. 4059 So. Bldg), United States Department of Agriculture, WA, DC 20250 (United States)

2009-12-15

The hypothesis of this study is that there is a statistical relationship between the lung cancer mortality rate and the intensity of fuel consumption (measured in gallons/square mile) at a particular location. We estimate cross-section regressions of the mortality rate due to lung cancer against the intensity of fuel consumption using local data for the entire US, before the US Clean Air Act (CAA) in 1974 and after the most recent policy revisions in 2004. The cancer rate improvement estimate suggests that up to 10 lung cancer deaths per 100,000 residents are avoided in the largest urban areas with highest fuel consumption per square mile. In New York City, for instance, the mortality reduction may be worth about $5.7 billion annually. Across the US, the estimated value of statistical life (VSL) benefit is $27.2 billion annually. There are likely three inseparable reasons that contributed importantly to this welfare improvement. First, the CAA regulations mandated reduction in specific carcinogenic chemicals or smog components. Second, technologies such as the catalytic converter (CC) and low-particulate diesel engine were adopted. Third, biofuels have had important roles, making the adoption of clean air technology possible and substituting for high emission fuels.

Cancer-risk benefits of clean fuel technology and policy: A statistical analysis

International Nuclear Information System (INIS)

Gallagher, Paul; Lazarus, William; Shapouri, Hosein; Conway, Roger; Duffield, James

2009-01-01

The hypothesis of this study is that there is a statistical relationship between the lung cancer mortality rate and the intensity of fuel consumption (measured in gallons/square mile) at a particular location. We estimate cross-section regressions of the mortality rate due to lung cancer against the intensity of fuel consumption using local data for the entire US, before the US Clean Air Act (CAA) in 1974 and after the most recent policy revisions in 2004. The cancer rate improvement estimate suggests that up to 10 lung cancer deaths per 100,000 residents are avoided in the largest urban areas with highest fuel consumption per square mile. In New York City, for instance, the mortality reduction may be worth about $5.7 billion annually. Across the US, the estimated value of statistical life (VSL) benefit is $27.2 billion annually. There are likely three inseparable reasons that contributed importantly to this welfare improvement. First, the CAA regulations mandated reduction in specific carcinogenic chemicals or smog components. Second, technologies such as the catalytic converter (CC) and low-particulate diesel engine were adopted. Third, biofuels have had important roles, making the adoption of clean air technology possible and substituting for high emission fuels.

Review of wood fuel from early thinning and plantation cleaning in the Netherlands

International Nuclear Information System (INIS)

Gelder, A. de

1998-01-01

Discussions regarding the use of wood fuels for commercial energy production in the Netherlands began in the 1990's. The main reasons for using wood fuel are: the political demand for using renewable energy, the need to reduce CO 2 emissions, and the lack of markets for surplus timber. Only 10 % of the area of Holland is forested. Therefore, early thinning and cleaning are important management tools for improving growth and producing better quality timber. The energy potential from early thinning and plantation cleaning could be between 400 000 and 570 000 dry tons annually. The Netherlands has not experience in harvesting energy wood. However, through the International Energy Agency/Bioenergy Agreement, knowledge gained in other countries, especially Denmark, Sweden and Finland, is being transferred to Holland. In 1996, there have been made field tests with Danish equipment. Although there are few technical barriers to wood fuel in the Netherlands, the economics of wood fuels consumption are affected by the low costs of fossil fuels and the high natural gas reserves. This is changing however, due to political concerns over the balance of greenhouse gases. In 1996, a small energy tax on fossil fuels was introduced and electricity suppliers are now selling an environmentally friendly 'green electricity'. Energy wood has a future in the Netherlands, although the total forest reserves would satisfy only a small percentage of energy requirements 5 refs

Fuel Composition and Performance Analysis of Endothermically Heated Fuels for Pulse Detonation Engines

Science.gov (United States)

2009-03-01

exchanger was constructed on an inner 2 in Inconel 625 schedule 10 pipe and an outer 2 ½ in Inconel 600 schedule 40 pipe 0.91 m (36 in) in length. The...switched to positions two and three for the remainder of the experiments. 46 The detonation tubes are fabricated from inconel and include heat...and four. Fuel Heating System 47 The fuel heating system centers around two pairs of inconel heat exchangers. The first pair was developed in

Measurement of the fuel temperature and the fuel-to-coolant heat transfer coefficient of Super Phenix 1 fuel elements

International Nuclear Information System (INIS)

Edelmann, M.

1995-12-01

A new measurement method for measuring the mean fuel temperature as well as the fuel-to-coolant heat transfer coefficient of fast breeder reactor subassemblies (SA) is reported. The method is based on the individual heat balance of fuel SA's after fast reactor shut-downs and uses only the plants normal SA outlet temperature and neutron power signals. The method was used successfully at the french breeder prototype Super Phenix 1. The mean SA fuel temperature as well as the heat transfer coefficient of all SPX SA's have been determined at power levels between 15 and 90% of nominal power and increasing fuel burn-up from 3 to 83 EFPD (Equivalent of Full Power-Days). The measurements also provided fuel and whole SA time constants. The estimated accuracy of measured fuel parameters is in the order of 10%. Fuel temperatures and SA outlet temperature transients were also calculated with the SPX1 systems code DYN2 for exactly the same fuel and reactor operating parameters as in the experiments. Measured fuel temperatures were higher than calculated ones in all cases. The difference between measured and calculated core mean values increases from 50 K at low power to 180 K at 90% n.p. This is about the double of the experimental error margins. Measured SA heat transfer coefficients are by nearly 20% lower than corresponding heat transfer parameters used in the calculations. Discrepancies found between measured and calculated results also indicate that either the transient heat transfer in the gap between fuel and cladding (gap conductance) might not be exactly reproduced in the computer code or that the gap in the fresh fuel was larger than assumed in the calculations. (orig.) [de

Analysis of pre-heated fuel combustion and heat-emission dynamics in a diesel engine

Science.gov (United States)

Plotnikov, S. A.; Kartashevich, A. N.; Buzikov, S. V.

2018-01-01

The article explores the feasibility of diesel fuel pre-heating. The research goal was to obtain and analyze the performance diagrams of a diesel engine fed with pre-heated fuel. The engine was tested in two modes: at rated RPMs and at maximum torque. To process the diagrams the authors used technique developed by the Central Diesel Research Institute (CDRI). The diesel engine’s heat emission curves were obtained. The authors concluded that fuel pre-heating shortened the initial phase of the combustion process and moderated the loads, thus making it possible to boost a diesel engine’s mean effective pressure.

Fuel coolant interaction experiment by direct electrical heating method

International Nuclear Information System (INIS)

Takeda, Tsuneo; Hirano, Kenmei

1979-01-01

In the PCM (Power Cooling Mismatch) experiments, the FCI (Fuel Coolant Interaction) test is one of necessary tests in order to predict various phenomena that occur during PCM in the core. A direct electrical heating method is used for the FCI tests for fuel pellet temperature of over 1000 0 C. Therefore, preheating is required before initiating the direct electrical heating. The fuel pin used in the FCI tests is typical LWR fuel element, which is surrounded by coolant water. It is undersirable to heat up the coolant water during preheating of the fuel pin. Therefore, a zirconia (ZrO 2 ) pellet which is similar to a UO 2 pellet in physical and chemical properties is used. Electric property (electric conductivity) of ZrO 2 is particularly suitable for direct electrical heating as in the case of UO 2 . In this experiment, ZrO 2 pellet (melting point 2500 0 C) melting was achieved by use of both preheating and direct electrical heating. Temperature changes of coolant and fuel surface, as well as the pressure change of coolant water, were measured. The molten fuel interacted with the coolant and generated shock waves. A portion of this molten fuel fragmented into small particles during this interaction. The peak pressure of the observed shock wave was about 35 bars. The damaged fuel pin was photographed after disassembly. This report shows the measured coolant pressure changes and the coolant temperature changes, as well as photographs of damaged fuel pin and fuel fragments. (author)

Clean fuel-magnesia bonded coal briquetting

Energy Technology Data Exchange (ETDEWEB)

Tosun, Yildirim I. [S. Demirel University Eng., Arch. Faculty Mining Eng. Department, Isparta (Turkey)

2007-10-15

Benefaction from coal fines as solid fuel in Turkey is very much important for economical development. Beneficiation from washed coal fines in the industry using solid fuel at lump size and in the municipal areas as an household solid fuel may be only provided by hot briquetting of the coal fines. The most practical common way of that benefication from coal fines in our country have been hot binding by sulfite liquor-sulfite liquor-melas and lime mixtures. Harmful the flue content of sulfite liquor-melas may only be eliminated by lime, a type of solid additive. However, cold bonded briquettes produced from coal fines are environmentally free. Just ash contents of these briquettes increase at a certain degree and heat content of them decrease at a certain extent. By using magnesia binder showed in this study, Tuncbilek lignite fines have been briquetted by cold and hot briquetting techniques. The qualities of briquettes produced by cold binders were compared with to those produced by other hot binding methods As a result, magnesia binder showed the similar characteristics with those of the briquettes produced by only cold bonded gypsum. Use of magnesite mixture and gypsum just as only cold binder was not suitable for the requirements from the coal briquettes to be used as solid fuels, particularly from household fuels, but just only as cold additive should be used. (author)

Experimental study on heat pipe heat removal capacity for passive cooling of spent fuel pool

International Nuclear Information System (INIS)

Xiong, Zhenqin; Wang, Minglu; Gu, Hanyang; Ye, Cheng

2015-01-01

Highlights: • A passively cooling SFP heat pipe with an 8.2 m high evaporator was tested. • Heat removed by the heat pipe is in the range of 3.1–16.8 kW. • The heat transfer coefficient of the evaporator is 214–414 W/m 2 /K. • The heat pipe performance is sensitive to the hot water temperature. - Abstract: A loop-type heat pipe system uses natural flow with no electrically driven components. Therefore, such a system was proposed to passively cool spent fuel pools during accidents to improve nuclear power station safety especially for station blackouts such as those in Fukushima. The heat pipe used for a spent fuel pool is large due to the spent fuel pool size. An experimental heat pipe test loop was developed to estimate its heat removal capacity from the spent fuel pool during an accident. The 7.6 m high evaporator is heated by hot water flowing vertically down in an assistant tube with a 207-mm inner diameter. R134a was used as the potential heat pipe working fluid. The liquid R134a level was 3.6 m. The tests were performed for water velocities from 0.7 to 2.1 × 10 −2 m/s with water temperatures from 50 to 90 °C and air velocities from 0.5 m/s to 2.5 m/s. The results indicate significant heat is removed by the heat pipe under conditions that may occur in the spent fuel pool

End-of-season heating fuel report

International Nuclear Information System (INIS)

1992-01-01

The year-end report notes that the 1991-92 heating season had lower average oil prices (retail home heating fuel) than the past two winters and prices remained relatively stable throughout the season. This year, the heating season average was $.87 per gallon, $1.05 for kerosene, and $1.33 for propane

Changing the energy climate: clean and green heat from grass biofuel pellets

International Nuclear Information System (INIS)

Jannasch, R.; Samson, R.; DeMaio, A.; Adams, T.; Ho Lem, C.

2001-01-01

Uncertain energy supplies and international agreements to reduce greenhouse gas (GHG) emissions have created unique opportunities for biofuel development. Pelleted fuels from warm season grasses such as switchgrass (Panicum virgatum) can be grown for $3-4/GigaJoule (GJ) with only minor emissions of CO 2 . Using close-coupled gasifer combustion technology, switchgrass fuel pellets emit 86%, 91%, 71% and 89% less CO 2 than electricity, heating oil, natural gas and propane, respectively. Every 100 ha of switchgrass converted into pellet form and used to displace fossil fuel for space-heating prevents the emission of 1000 tonnes of CO 2 . Heating an average Ontario house with a 90GJ heat demand costs $1213 with switchgrass pellets compared to $2234, $1664, $882 and $3251 with electricity, heating oil, natural gas and propane, respectively. An estimated 23.4 million acres of agricultural land in Canada could potentially be converted to perennial grass biofuel production. The depressed farm sector would benefit economically from energy farming. Low-grade heat energy derived from grass pellets could displace some of the 30,000 GigaWatt Hours of electricity currently used for home heating in Quebec, Ontario and Manitoba. Surplus electricity could be exported or used to replace nuclear or coal burning plants. Contrary to prevailing beliefs that reducing GHG emissions will raise societal energy costs, pelletized grass biofuels could provide consumers with less expensive and more GHG-friendly heating options than most fossil energy sources. If the political support and direction exist to implement the Kyoto Protocol as intended, grass pellets could well become a heating fuel of choice in North America. (author)

Investigation Status of Heat Exchange while Boiling Hydrocarbon Fuel

Directory of Open Access Journals (Sweden)

D. S. Obukhov

2006-01-01

Full Text Available The paper contains analysis of heat exchange investigations while boiling hydrocarbon fuel. The obtained data are within the limits of the S.S. Kutateladze dependence proposed in 1939. Heat exchange at non-stationary heat release has not been investigated. The data for hydrocarbon fuel with respect to critical density of heat flow are not available even for stationary conditions.

Computer code TOBUNRAD for PWR fuel bundle heat-up calculations

International Nuclear Information System (INIS)

Shimooke, Takanori; Yoshida, Kazuo

1979-05-01

The computer code TOBUNRAD developed is for analysis of ''fuel-bundle'' heat-up phenomena in a loss-of-coolant accident of PWR. The fuel bundle consists of fuel pins in square lattice; its behavior is different from that of individual pins during heat-up. The code is based on the existing TOODEE2 code which analyzes heat-up phenomena of single fuel pins, so that the basic models of heat conduction and transfer and coolant flow are the same as the TOODEE2's. In addition to the TOODEE2 features, unheated rods are modeled and radiation heat loss is considered between fuel pins, a fuel pin and other heat sinks. The TOBUNRAD code is developed by a new FORTRAN technique which makes it possible to interrupt a flow of program controls wherever desired, thereby attaching several subprograms to the main code. Users' manual for TOBUNRAD is presented: The basic program-structure by interruption method, physical and computational model in each sub-code, usage of the code and sample problems. (author)

Review of direct electrical heating experiments on irradiated mixed-oxide fuel

International Nuclear Information System (INIS)

Fenske, G.R.; Bandyopadhyay, G.

1982-01-01

Results of approximately 50 out-of-reactor experiments that simulated various stages of a loss-of-flow event with irradiated fuel are presented. The tests, which utilized the direct electrical heating technique to simulate nuclear heating, were performed either on fuel segments with their original cladding intact or on fuel segments that were extruded into quartz tubes. The test results demonstrated that the macro- and microscopic fuel behavior was dependent on a number of variables including fuel heating rate, thermal history prior to a transient, the number of heating cycles, type of cladding (quartz vs stainless steel), and fuel burnup

Fresh fuel pre-heating device in reactor facility

International Nuclear Information System (INIS)

Samejima, Asakuni.

1988-01-01

Purpose: To simplify the structure of a fresh nuclear fuel pre-heating device and improve the reliability to gas supply. Constitution: Fresh fuels taken out from a fresh fuel stredge rack and contained in a fuel strage pipe of a fuel transportation cask are pre-heated at the pre-stage of transfer by sending heating gases from the outside. Gas outlet pipes of the device are led out from the lower portion of the strage pipe, disposed side by side at the top of the strage pipe and opened upwardly. Further, gas supply pipes are connected to the inside of a movable guiding cylinder on the side of the floor surface and the opening end of return pipes are opposed to the exit opening end of the strage pipe. In such a constitution, a gas recycling loop can be formed between the strage pipe and the gas heating device by way of the movable guiding cylinder only by the operation of combining the fuel strage pipe of the transportation cask and the movable guiding pipe disposed on the side of the floor surface. Thus, the coupling structure is facilitated, the connection operation can surely be conducted to improve the reliability as compared with the conventional case. (Horiuchi, T.)

Nuclear fuel safety studies by laser pulse heating

International Nuclear Information System (INIS)

Viswanadham, C.S.; Kumar, Santosh; Dey, G.K.; Kutty, T.R.G.; Khan, K.B.; Kumar, Arun; Jathar, V.P.; Sahoo, K.C.

2009-01-01

The behaviour of nuclear fuels under transient heating conditions is vital to nuclear safety. A laser pulse based heating system to simulate the transient heating conditions experienced by the fuel during reactor accidents like LOCA and RIA is under development at BARC, Mumbai. Some of the concepts used in this system are under testing in pilot studies. This paper describes the results of some pilot studies carried out on unirradiated UO 2 specimens by laser pulse heating, followed by metallography and X-ray diffraction measurements. (author)

POST CRITICAL HEAT TRANSFER AND FUEL CLADDING OXIDATION

Directory of Open Access Journals (Sweden)

Vojtěch Caha

2016-12-01

Full Text Available The knowledge of heat transfer coefficient in the post critical heat flux region in nuclear reactor safety is very important. Although the nuclear reactors normally operate at conditions where critical heat flux (CHF is not reached, accidents where dryout occur are possible. Most serious postulated accidents are a loss of coolant accident or reactivity initiated accident which can lead to CHF or post CHF conditions and possible disruption of core integrity. Moreover, this is also influenced by an oxide layer on the cladding surface. The paper deals with the study of mathematical models and correlations used for heat transfer calculation, especially in post dryout region, and fuel cladding oxidation kinetics of currently operated nuclear reactors. The study is focused on increasing of accuracy and reliability of safety limit calculations (e.g. DNBR or fuel cladding temperature. The paper presents coupled code which was developed for the solution of forced convection flow in heated channel and oxidation of fuel cladding. The code is capable of calculating temperature distribution in the coolant, cladding and fuel and also the thickness of an oxide layer.

Cardiovascular disease - risk benefits of clean fuel technology and policy. A statistical analysis

Energy Technology Data Exchange (ETDEWEB)

Gallagher, Paul; Fischer, Amelia [Economics Department, 481 Heady Hall, Iowa State University, Ames Iowa 50011 (United States); Lazarus, William; Bachewe, Fantu [Applied Economics Department, 253 COB, University of Minnesota, St. Paul, MN 55455 (United States); Shapouri, Hosein; Conway, Roger [Office of Energy Policy and New Uses, 400 Independence Avenue, SW (Rm.4059 So. Bldg), United States Department of Agriculture, Washington, DC 20250 (United States)

2010-02-15

The hypothesis of this study is that there is a statistical relationship between the cardiovascular disease mortality rate and the intensity of fuel consumption (measured in gallons/square mile) at a particular location. We estimate cross-sectional regressions of the mortality rate due to cardiovascular disease against the intensity of fuel consumption using local data for the entire US, before the US Clean Air Act (CAA) in 1974 and after the most recent policy revisions in 2004. The cardiovascular disease rate improvement estimate suggests that up to 60 cardiovascular disease deaths per 100,000 residents are avoided in the largest urban areas with highest fuel consumption per square mile. In New York City, for instance, the mortality reduction may be worth about $30.3 billion annually. Across the US, the estimated Value of Statistical Life (VSL) benefit is $202.7 billion annually. There are likely three inseparable reasons that contributed importantly to this welfare improvement. First, the CAA regulations banned leaded gasoline, and mandated reduction in specific chemicals and smog components. Second, technologies such as the Catalytic Converter (CC) for the automobile and the low particulate diesel engine were adopted. Third, biofuels have had important roles, making the adoption of clean air technology possible and substituting for high emission fuels. (author)

Cardiovascular disease-risk benefits of clean fuel technology and policy: A statistical analysis

Energy Technology Data Exchange (ETDEWEB)

Gallagher, Paul, E-mail: paulg@iastate.ed [Economics Department, 481 Heady Hall, Iowa State University, Ames Iowa 50011 (United States); Lazarus, William [Applied Economics Department, 253 COB, University of Minnesota, St. Paul, MN 55455 (United States); Shapouri, Hosein; Conway, Roger [Office of Energy Policy and New Uses, 400 Independence Avenue, SW (Rm.4059 So. Bldg), United States Department of Agriculture, Washington, DC 20250 (United States); Bachewe, Fantu [Applied Economics Department, 253 COB, University of Minnesota, St. Paul, MN 55455 (United States); Fischer, Amelia [Economics Department, 481 Heady Hall, Iowa State University, Ames Iowa 50011 (United States)

2010-02-15

The hypothesis of this study is that there is a statistical relationship between the cardiovascular disease mortality rate and the intensity of fuel consumption (measured in gallons/square mile) at a particular location. We estimate cross-sectional regressions of the mortality rate due to cardiovascular disease against the intensity of fuel consumption using local data for the entire US, before the US Clean Air Act (CAA) in 1974 and after the most recent policy revisions in 2004. The cardiovascular disease rate improvement estimate suggests that up to 60 cardiovascular disease deaths per 100,000 residents are avoided in the largest urban areas with highest fuel consumption per square mile. In New York City, for instance, the mortality reduction may be worth about $30.3 billion annually. Across the US, the estimated Value of Statistical Life (VSL) benefit is $202.7 billion annually. There are likely three inseparable reasons that contributed importantly to this welfare improvement. First, the CAA regulations banned leaded gasoline, and mandated reduction in specific chemicals and smog components. Second, technologies such as the Catalytic Converter (CC) for the automobile and the low particulate diesel engine were adopted. Third, biofuels have had important roles, making the adoption of clean air technology possible and substituting for high emission fuels.

Cardiovascular disease-risk benefits of clean fuel technology and policy: A statistical analysis

International Nuclear Information System (INIS)

Gallagher, Paul; Lazarus, William; Shapouri, Hosein; Conway, Roger; Bachewe, Fantu; Fischer, Amelia

2010-01-01

The hypothesis of this study is that there is a statistical relationship between the cardiovascular disease mortality rate and the intensity of fuel consumption (measured in gallons/square mile) at a particular location. We estimate cross-sectional regressions of the mortality rate due to cardiovascular disease against the intensity of fuel consumption using local data for the entire US, before the US Clean Air Act (CAA) in 1974 and after the most recent policy revisions in 2004. The cardiovascular disease rate improvement estimate suggests that up to 60 cardiovascular disease deaths per 100,000 residents are avoided in the largest urban areas with highest fuel consumption per square mile. In New York City, for instance, the mortality reduction may be worth about $30.3 billion annually. Across the US, the estimated Value of Statistical Life (VSL) benefit is $202.7 billion annually. There are likely three inseparable reasons that contributed importantly to this welfare improvement. First, the CAA regulations banned leaded gasoline, and mandated reduction in specific chemicals and smog components. Second, technologies such as the Catalytic Converter (CC) for the automobile and the low particulate diesel engine were adopted. Third, biofuels have had important roles, making the adoption of clean air technology possible and substituting for high emission fuels.

Ultra Efficient CHHP Using a High Temperature Fuel Cell to Provide On-Site Process Reducing Gas, Clean Power, and Heat

Energy Technology Data Exchange (ETDEWEB)

Jahnke, Fred C. [Fuelcell Energy, Inc., Danbury, CT (United States)

2015-06-30

FuelCell Energy and ACuPowder investigated and demonstrated the use of waste anode exhaust gas from a high temperature fuel cell for replacing the reducing gas in a metal processing furnace. Currently companies purchase high pressure or liquefied gases for the reducing gas which requires substantial energy in production, compression/liquefaction, and transportation, all of which is eliminated by on-site use of anode exhaust gas as reducing gas. We performed research on the impact of the gas composition on product quality and then demonstrated at FuelCell Energy’s manufacturing facility in Torrington, Connecticut. This demonstration project continues to operate even though the research program is completed as it provides substantial benefits to the manufacturing facility by supplying power, heat, and hydrogen.

The demand for clean-fuel vehicles by Dutch local authorities. A stated choice analysis

Energy Technology Data Exchange (ETDEWEB)

Hagen, P.

2012-08-15

Previous research showed that the era of cheap fossil fuels is over. Also, 23% of the worldwide emission of CO2 is produced by road transport. These problems demand a change in the propulsion of vehicles. Because the diffusion of clean-fuel vehicles is not happening at this moment, something has to change. Rogers' diffusion of innovation theory is used to state that a critical mass of vehicles is needed to stimulate the diffusion of these vehicles. Due to public procurement Dutch local authorities (DLA's) can help stimulating this diffusion. Unfortunately these DLA's are not purchasing clean-fuel vehicles yet. To gain insight in what is hampering the diffusion of these vehicles by DLA's, a discrete choice experiment was created about the preferences by these DLA's. Six vehicle attributes were used to describe each vehicle. The results showed that the initial purchase price and the amount of local emission were experienced as the most important attributes by DLA's, where initial purchase price has a negative influence and local emission a positive influence in the choice for a new vehicle. Next, fuel price, range and availability of the fuel were found evenly important. Fuel price had a negative influence and both range and availability of fuel had a positive influence on the choice for a new vehicle. Finally, time to refuel/recharge was found least important and also negatively influencing the choice.

Development of Passive Fuel Cell Thermal Management Heat Exchanger

Science.gov (United States)

Burke, Kenneth A.; Jakupca, Ian J.; Colozza, Anthony J.

2010-01-01

The NASA Glenn Research Center is developing advanced passive thermal management technology to reduce the mass and improve the reliability of space fuel cell systems for the NASA Exploration program. The passive thermal management system relies on heat conduction within highly thermally conductive cooling plates to move the heat from the central portion of the cell stack out to the edges of the fuel cell stack. Using the passive approach eliminates the need for a coolant pump and other cooling loop components within the fuel cell system which reduces mass and improves overall system reliability. Previous development demonstrated the performance of suitable highly thermally conductive cooling plates that could conduct the heat, provide a sufficiently uniform temperature heat sink for each cell of the fuel cell stack, and be substantially lighter than the conventional thermal management approach. Tests were run with different materials to evaluate the design approach to a heat exchanger that could interface with the edges of the passive cooling plates. Measurements were made during fuel cell operation to determine the temperature of individual cooling plates and also to determine the temperature uniformity from one cooling plate to another.

Configuring a fuel cell based residential combined heat and power system

Science.gov (United States)

Ahmed, Shabbir; Papadias, Dionissios D.; Ahluwalia, Rajesh K.

2013-11-01

The design and performance of a fuel cell based residential combined heat and power (CHP) system operating on natural gas has been analyzed. The natural gas is first converted to a hydrogen-rich reformate in a steam reformer based fuel processor, and the hydrogen is then electrochemically oxidized in a low temperature polymer electrolyte fuel cell to generate electric power. The heat generated in the fuel cell and the available heat in the exhaust gas is recovered to meet residential needs for hot water and space heating. Two fuel processor configurations have been studied. One of the configurations was explored to quantify the effects of design and operating parameters, which include pressure, temperature, and steam-to-carbon ratio in the fuel processor, and fuel utilization in the fuel cell. The second configuration applied the lessons from the study of the first configuration to increase the CHP efficiency. Results from the two configurations allow a quantitative comparison of the design alternatives. The analyses showed that these systems can operate at electrical efficiencies of ∼46% and combined heat and power efficiencies of ∼90%.

Cleaning and extraction apparatus in a nuclear fuel reprocessing

International Nuclear Information System (INIS)

Nakamura, Yoshiaki.

1983-01-01

Purpose : To eliminate the requirement for the decomposition and cleaning of a centrifugal extractor upon re-processing of FBR type reactor fuels, by preventing solid fission products from depositing on a rotary body of the centrifugal extractor. Constitution : A cleaning and extraction apparatus comprising a combination of a centrifugal cleaner and a centrifugal extractor is used for shortening the contact time between the process liquid and the extraction solvent in FBR type reactor fuel re-processing, and variable parameters are adjusted so that the following equation can be satisfied for avoiding the deposition of solids onto the rotary body of the centrifugal extractor: lsub(e). (rsub(le) 2 + rsub(2r) 2 ) . Nsub(e) . Qsub(c)/ lsub(c) (rsub(lc) 2 + rsub(2c) 2 ) . Nsub(c) . Qsub(e) < 0.8 where Qsub(c) : flow rate to be processed in a centrifugal cleaner, lsub(c) : length of the rotary body, rsub(2c) : radius of a rotary body, rsub(le) : distance from the center to the liquid-extracting hole of the rotary body center to the liquid-extraction hole, Nsub(c) : number of revolution of the rotary body, Qsub(e) : amount of flowrate to be treated in the centrifugal extractor, lsub(e) : length of the rotary body, rsub(2e) : radius for the rotary body, rsub(le) : distance from the center of the rotary body to the liquid discharging aperture and Nsub(e) : number of rotation of the rotary body. (Ikeda, J.)

Activity release from damaged fuel during the Paks-2 cleaning tank incident in the spent fuel storage pool

International Nuclear Information System (INIS)

Hozer, Zoltan; Szabo, Emese; Pinter, Tamas; Varju, Ilona Baracska; Bujtas, Tibor; Farkas, Gabor; Vajda, Nora

2009-01-01

During crud removal operations the integrity of 30 fuel assemblies was lost at high temperature at the unit No. 2 of the Paks NPP. Part of the fission products was released from the damaged fuel into the coolant of the spent fuel storage pool. The gaseous fission products escaped through the chimney from the reactor hall. The volatile and non-volatile materials remained mainly in the coolant and were collected on the filters of water purification system. The activity release from damaged fuel rods during the Paks-2 cleaning tank incident was estimated on the basis of coolant activity concentration measurements and chimney activity data. The typical release rate of noble gases, iodine and caesium was 1-3%. The release of non-volatile fission products and actinides was also detected.

Activity release from damaged fuel during the Paks-2 cleaning tank incident in the spent fuel storage pool

Energy Technology Data Exchange (ETDEWEB)

Hozer, Zoltan, E-mail: hozer@aeki.kfki.h [Hungarian Academy of Sciences KFKI Atomic Energy Research Institute, H-1525 Budapest 114, P.O. Box 49 (Hungary); Szabo, Emese [Hungarian Academy of Sciences KFKI Atomic Energy Research Institute, H-1525 Budapest 114, P.O. Box 49 (Hungary); Pinter, Tamas; Varju, Ilona Baracska; Bujtas, Tibor; Farkas, Gabor [Nuclear Power Plant Paks, H-7031 Paks, P.O. Box 71 (Hungary); Vajda, Nora [Institute of Nuclear Techniques, Budapest University of Technology and Economics, H-1521 Budapest, Muegyetem rakpart 9 (Hungary)

2009-07-01

During crud removal operations the integrity of 30 fuel assemblies was lost at high temperature at the unit No. 2 of the Paks NPP. Part of the fission products was released from the damaged fuel into the coolant of the spent fuel storage pool. The gaseous fission products escaped through the chimney from the reactor hall. The volatile and non-volatile materials remained mainly in the coolant and were collected on the filters of water purification system. The activity release from damaged fuel rods during the Paks-2 cleaning tank incident was estimated on the basis of coolant activity concentration measurements and chimney activity data. The typical release rate of noble gases, iodine and caesium was 1-3%. The release of non-volatile fission products and actinides was also detected.

Clean fuels for resource-poor settings: A systematic review of barriers and enablers to adoption and sustained use.

Science.gov (United States)

Puzzolo, Elisa; Pope, Daniel; Stanistreet, Debbi; Rehfuess, Eva A; Bruce, Nigel G

2016-04-01

Access to, and sustained adoption of, clean household fuels at scale remains an aspirational goal to achieve sufficient reductions in household air pollution (HAP) in order to impact on the substantial global health burden caused by reliance on solid fuels. To systematically appraise the current evidence base to identify: (i) which factors enable or limit adoption and sustained use of clean fuels (namely liquefied petroleum gas (LPG), biogas, solar cooking and alcohol fuels) in low- and middle-income countries; (ii) lessons learnt concerning equitable scaling-up of programmes of cleaner cooking fuels in relation to poverty, urban-rural settings and gender. A mixed-methods systematic review was conducted using established review methodology and extensive searches of published and grey literature sources. Data extraction and quality appraisal of quantitative, qualitative and case studies meeting inclusion criteria were conducted using standardised methods with reliability checking. Forty-four studies from Africa, Asia and Latin America met the inclusion criteria (17 on biogas, 12 on LPG, 9 on solar, 6 on alcohol fuels). A broad range of inter-related enabling and limiting factors were identified for all four types of intervention, operating across seven pre-specified domains (i.e. fuel and technology characteristics, household and setting characteristics, knowledge and perceptions, financial, tax and subsidy aspects, market development, regulation, legislation and standards, and programme and policy mechanisms) and multiple levels (i.e. household, community, national). All domains matter and the majority of factors are common to all clean fuels interventions reviewed although some are fuel and technology-specific. All factors should therefore be taken into account and carefully assessed during planning and implementation of any small- and large-scale initiative aiming at promoting clean fuels for household cooking. Despite limitations in quantity and quality of the

40 CFR 69.52 - Non-motor vehicle diesel fuel.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Non-motor vehicle diesel fuel. 69.52... (CONTINUED) SPECIAL EXEMPTIONS FROM REQUIREMENTS OF THE CLEAN AIR ACT Alaska § 69.52 Non-motor vehicle diesel... NRLM diesel fuel. (5) Exempt NRLM diesel fuel and heating oil must be segregated from motor vehicle...

Clean steels for fusion

International Nuclear Information System (INIS)

Gelles, D.S.

1995-03-01

Fusion energy production has an inherent advantage over fission: a fuel supply with reduced long term radioactivity. One of the leading candidate materials for structural applications in a fusion reactor is a tungsten stabilized 9% chromium Martensitic steel. This alloy class is being considered because it offers the opportunity to maintain that advantage in the reactor structure as well as provide good high temperature strength and radiation induced swelling and embrittlement resistance. However, calculations indicate that to obtain acceptable radioactivity levels within 500 years after service, clean steel will be required because the niobium impurity levels must be kept below about 2 appm and nickel, molybdenum, nitrogen, copper, and aluminum must be intentionally restricted. International efforts are addressing the problems of clean steel production. Recently, a 5,000 kg heat was vacuum induction melted in Japan using high purity commercial raw materials giving niobium levels less than 0.7 appm. This paper reviews the need for reduced long term radioactivity, defines the advantageous properties of the tungsten stabilized Martensitic steel class, and describes the international efforts to produce acceptable clean steels

Combustion chamber heat transfer characterization of LOX/hydrocarbon-type propellants

Science.gov (United States)

Schoenman, Leonard

1987-01-01

The gas-side heat transfer rates for LOX/propane and LOX/ethanol are experimentally characterized using a 1000 lb thrust water-cooled calorimeter chamber. The effects of injector element type and fuel film cooling are defined as a function of mixture ratio. The interaction of fuel injected through the resonator cavities on heat transfer and wall soot buildup are displayed as a function of time, axial distance, fuel coolant flow rate, and mixture ratio. Comparisons between clean-burning ethanol and sooting propane show a large difference between the two fuels and significantly higher than expected heat flux levels for ethanol in the throat region.

Heat and fuel coupled operation of a high temperature polymer electrolyte fuel cell with a heat exchanger methanol steam reformer

Science.gov (United States)

Schuller, G.; Vázquez, F. Vidal; Waiblinger, W.; Auvinen, S.; Ribeirinha, P.

2017-04-01

In this work a methanol steam reforming (MSR) reactor has been operated thermally coupled to a high temperature polymer electrolyte fuel cell stack (HT-PEMFC) utilizing its waste heat. The operating temperature of the coupled system was 180 °C which is significantly lower than the conventional operating temperature of the MSR process which is around 250 °C. A newly designed heat exchanger reformer has been developed by VTT (Technical Research Center of Finland LTD) and was equipped with commercially available CuO/ZnO/Al2O3 (BASF RP-60) catalyst. The liquid cooled, 165 cm2, 12-cell stack used for the measurements was supplied by Serenergy A/S. The off-heat from the electrochemical fuel cell reaction was transferred to the reforming reactor using triethylene glycol (TEG) as heat transfer fluid. The system was operated up to 0.4 A cm-2 generating an electrical power output of 427 Wel. A total stack waste heat utilization of 86.4% was achieved. It has been shown that it is possible to transfer sufficient heat from the fuel cell stack to the liquid circuit in order to provide the needed amount for vaporizing and reforming of the methanol-water-mixture. Furthermore a set of recommendations is given for future system design considerations.

Heat removal in gas-cooled fuel rod clusters

International Nuclear Information System (INIS)

Rehme, K.

1975-01-01

For a thermo- and fluid-dynamic analysis of fuel rod cluster subchannels for gas-cooled breeder reactors, the following values must be verified: a) friction coefficient as flow parameter; b) Stanton number as heat transfer parameter; c) influence of spacers on friction coefficient and Stanton number; d) heat and mass exchange between subchannels with different temperatures. These parameters are established by combining results of single experiments and of integral experiments. Mention is made of further studies to be performed in order to determine the heat removal from gas-cooled fast breeder fuel elements. (HR) [de

ENVIRONMENTAL TECHNOLOGY VERIFICATION, TEST REPORT OF MOBILE SOURCE EMISSIONS CONTROL DEVICES/CLEAN DIESEL TECHNOLOGIES FUEL BORNE CATALYST WITH CLEANAIR SYSTEM'S DIESEL OXIDATION CATALYST

Science.gov (United States)

The Environmental Technology Verification report discusses the technology and performance of the Fuel-Borne Catalyst with CleanAir System's Diesel Oxidation Catalyst manufactured by Clean Diesel Technologies, Inc. The technology is a fuel-borne catalyst used in ultra low sulfur d...

Simulation of a 250 kW diesel fuel processor/PEM fuel cell system

Science.gov (United States)

Amphlett, J. C.; Mann, R. F.; Peppley, B. A.; Roberge, P. R.; Rodrigues, A.; Salvador, J. P.

Polymer-electrolyte membrane (PEM) fuel cell systems offer a potential power source for utility and mobile applications. Practical fuel cell systems use fuel processors for the production of hydrogen-rich gas. Liquid fuels, such as diesel or other related fuels, are attractive options as feeds to a fuel processor. The generation of hydrogen gas for fuel cells, in most cases, becomes the crucial design issue with respect to weight and volume in these applications. Furthermore, these systems will require a gas clean-up system to insure that the fuel quality meets the demands of the cell anode. The endothermic nature of the reformer will have a significant affect on the overall system efficiency. The gas clean-up system may also significantly effect the overall heat balance. To optimize the performance of this integrated system, therefore, waste heat must be used effectively. Previously, we have concentrated on catalytic methanol-steam reforming. A model of a methanol steam reformer has been previously developed and has been used as the basis for a new, higher temperature model for liquid hydrocarbon fuels. Similarly, our fuel cell evaluation program previously led to the development of a steady-state electrochemical fuel cell model (SSEM). The hydrocarbon fuel processor model and the SSEM have now been incorporated in the development of a process simulation of a 250 kW diesel-fueled reformer/fuel cell system using a process simulator. The performance of this system has been investigated for a variety of operating conditions and a preliminary assessment of thermal integration issues has been carried out. This study demonstrates the application of a process simulation model as a design analysis tool for the development of a 250 kW fuel cell system.

Conjugate heat transfer simulations of advanced research reactor fuel

Energy Technology Data Exchange (ETDEWEB)

Piro, M.H.A., E-mail: pirom@aecl.ca; Leitch, B.W.

2014-07-01

Highlights: • Temperature predictions are enhanced by coupling heat transfer in solid and fluid zones. • Seven different cases are considered to observe trends in predicted temperature and pressure. • The seven cases consider high/medium/low power, flow, burnup, fuel material and geometry. • Simulations provide temperature predictions for performance/safety. Boiling is unlikely. • Simulations demonstrate that a candidate geometry can enhance performance/safety. - Abstract: The current work presents numerical simulations of coupled fluid flow and heat transfer of advanced U–Mo/Al and U–Mo/Mg research reactor fuels in support of performance and safety analyses. The objective of this study is to enhance predictions of the flow regime and fuel temperatures through high fidelity simulations that better capture various heat transfer pathways and with a more realistic geometric representation of the fuel assembly in comparison to previous efforts. Specifically, thermal conduction, convection and radiation mechanisms are conjugated between the solid and fluid regions. Also, a complete fuel element assembly is represented in three dimensional space, permitting fluid flow and heat transfer to be simulated across the entire domain. Seven case studies are examined that vary the coolant inlet conditions, specific power, and burnup to investigate the predicted changes in the pressure drop in the coolant and the fuel, clad and coolant temperatures. In addition, an alternate fuel geometry is considered with helical fins (replacing straight fins in the existing design) to investigate the relative changes in predicted fluid and solid temperatures. Numerical simulations predict that the clad temperature is sensitive to changes in the thermal boundary layer in the coolant, particularly in simultaneously developing flow regions, while the temperature in the fuel is anticipated to be unaffected. Finally, heat transfer between fluid and solid regions is enhanced with

Clean/alternative fueled fleet programs - 1990 Amendments to the Clean Air Act, the Colorado Air Pollution Prevention and Control Act, and Denver City and County regulations

International Nuclear Information System (INIS)

Bowles, S.L.; Manderino, L.A.

1993-01-01

Despite substantial regulations for nearly two decades, attainment of this ambient standards for ozone and carbon monoxide (CO) remain difficult goals to achieve, Even with of ozone precursors and CO. The 1990 Amendments to the Clean Air Act (CAA90) prescribe further reductions of mobile source emissions. One such reduction strategy is using clean fuels, such as methanol, ethanol, or other alcohols (in blends of 85 percent or more alcohol with gasoline or other fuel), reformulated gasoline or diesel, natural gas, liquified petroleum gas, hydrogen, or electricity. There are regulatory measures involving special fuels which will be required in areas heavily polluted with ozone and CO. The state of Colorado recently passed the 1992 Air Pollution Prevention and Control Act which included provisions for the use of alternative fuels which will be implemented in 1994. In addition to adhering to the Colorado state regulations, the city and county of Denver also have regulations pertaining to the use of alternative fuels in fleets of 10 or more vehicles. Denver's program began in 1992. This paper will address the issue of fleet conversion and its impact on industry in Colorado, and Denver in particular

Solution of the conjugated heat transfer problem for the fuel elements assemblies

International Nuclear Information System (INIS)

Golba, V.S.; Ivanenko, I.J.; Zinina, G.A.

1997-01-01

The paper presents the assemblies conjugated heat conductivity problem calculation and experimental method. The method is based on the temperature superposition modified concept and subchannel method and allows to predict the fuel elements surface temperatures with availability of fuel elements inside structure of any complication caused by technological and working defects and with availability of depositions with low heat conductivity on the fuel elements surfaces. According to the method developed the partial solutions of the heat conductivity equation at the heat removal boundaries (solid-liquid) are found separately for the fuel elements and for the liquid. The heat conductivity equation partial solutions for the fuel elements are predicted by calculations. The coolant heat conductivity equation partial solution ('influence functions') data massif is obtained in present work experimentally in the fuel assembly model consists of 7 tube bundle of fuel elements imitators placed in right grating with relative grating step equal to 1.1 and cooled by eutectic alloy Pb-Bi. It is shown that 'subchannel prediction method' decreases the crosswise heat transfer in comparison with crosswise heat transfer, when the fuel element inside structure is taken into account. Also in the paper it is shown that it is possible to realize the assembly temperature prediction method suggested without carrying out the experiments in the assembly's model in order to get the external problem influence functions'. (author)

Flex-Fuel Two-Stroke Snowmobile: Development of a Flex-Fuel, Two-Stroke, Direct-Injection Snowmobile for Use in the Clean Snowmobile Challenge and National Parks

Science.gov (United States)

2009-09-01

The University of Idaho's entry into the 2009 SAE Clean Snowmobile Challenge (CSC) was a semi-direct-injection (SDI) two-stroke powered REV-XP snowmobile modified to use flex fuel. The flex fuel engine produces stock engine power on any blend of etha...

Microfabricated fuel heating value monitoring device

Science.gov (United States)

Robinson, Alex L [Albuquerque, NM; Manginell, Ronald P [Albuquerque, NM; Moorman, Matthew W [Albuquerque, NM

2010-05-04

A microfabricated fuel heating value monitoring device comprises a microfabricated gas chromatography column in combination with a catalytic microcalorimeter. The microcalorimeter can comprise a reference thermal conductivity sensor to provide diagnostics and surety. Using microfabrication techniques, the device can be manufactured in production quantities at a low per-unit cost. The microfabricated fuel heating value monitoring device enables continuous calorimetric determination of the heating value of natural gas with a 1 minute analysis time and 1.5 minute cycle time using air as a carrier gas. This device has applications in remote natural gas mining stations, pipeline switching and metering stations, turbine generators, and other industrial user sites. For gas pipelines, the device can improve gas quality during transfer and blending, and provide accurate financial accounting. For industrial end users, the device can provide continuous feedback of physical gas properties to improve combustion efficiency during use.

Steam cleaning device

International Nuclear Information System (INIS)

Karaki, Mikio; Muraoka, Shoichi.

1985-01-01

Purpose: To clean complicated and long objects to be cleaned having a structure like that of nuclear reactor fuel assembly. Constitution: Steams are blown from the bottom of a fuel assembly and soon condensated initially at the bottom of a vertical water tank due to water filled therein. Then, since water in the tank is warmed nearly to the saturation temperature, purified water is supplied from a injection device below to the injection device above the water tank on every device. In this way, since purified water is sprayed successively from below to above and steams are condensated in each of the places, the entire fuel assembly elongated in the vertical direction can be cleaned completely. Water in the reservoir goes upward like the steam flow and is drained together with the eliminated contaminations through an overflow pipe. After the cleaning has been completed, a main steam valve is closed and the drain valve is opened to drain water. (Kawakami, Y.)

Clean energy, non-clean energy, and economic growth in the MIST countries

International Nuclear Information System (INIS)

Pao, Hsiao-Tien; Li, Yi-Ying; Hsin-Chia Fu

2014-01-01

This paper explores the causal relationship between clean (renewable/nuclear) and non-clean energy consumption and economic growth in emerging economies of the MIST (Mexico, Indonesia, South Korea, and Turkey) countries. The panel co-integration tests reveal that there is a long-term equilibrium relationship among GDP, capital formation, labor force, renewable/nuclear, and fossil fuel energy consumption. The panel causality results indicate that (1) there is a positive unidirectional short-run causality from fossil fuel energy consumption to economic growth with a bidirectional long-run causality; (2) there is a unidirectional long-run causality from renewable energy consumption to economic growth with positive bidirectional short-run causality, and a long-run causality from renewable to fossil fuel energy consumption with negative short-run feedback effects; and (3) there is a bidirectional long-run causality between nuclear energy consumption and economic growth and a long-run causality from fossil fuel energy consumption to nuclear energy consumption with positive short-run feedback effects. These suggest that MIST countries should be energy-dependent economies and that energy conservation policies may depress their economic development. However, developing renewable and nuclear energy is a viable solution for addressing energy security and climate change issues, and creating clean and fossil fuel energy partnerships could enhance a sustainable energy economy. - Highlights: • This novel study can provide more robust bases to strengthen sustainable energy policy settings. • Fossil fuel/nuclear energy use and economic growth is bidirectional causality. • Renewable energy consumption long term causes economic growth. • There is substitutability between renewable and fossil fuel energy. • Clean and non-clean energy partnerships can achieve a sustainable energy economy

Fuel cell heat utilization system; Nenryo denchi netsuriyo sochi

Energy Technology Data Exchange (ETDEWEB)

Urata, T. [Tokyo (Japan); Omura, T. [Tokyo (Japan)

1995-07-04

In the conventional fuel cell heat utilization system, the waste heat is recovered to be utilized by either the waste heat recovery heat exchanger or the waste heat recovery steam. In the employment of the waste heat recovery heat exchanger system, however, the utility value is decreased when the temperature of the waste heat is lowered. Contrarily, in the employment of the waste heat recovery steam system, the supplementary water requirement is increased corresponding to the amount of waste heat recovery steam, resulting in the cost increase for water treatment. This invention solves the problem. In the invented fuel cell heat utilization system, a pressurized water from the steam separator is introduced into the second circuit to utilize directly the heat in the heat utilization system without employing the heat exchanger. If a blowdown valve is installed between the second circuit heat utilization system and the steam separator, the heat loss due to the blowdown can be reduced, since the low temperature water is blown down after being utilized in the heat utilization system. 4 figs.

The 3R anthracite clean coal technology: Economical conversion of brown coal to anthracite type clean coal by low temperature carbonization pre-treatment process

Directory of Open Access Journals (Sweden)

Someus Edward

2006-01-01

Full Text Available The preventive pre-treatment of low grade solid fuels is safer, faster, better, and less costly vs. the "end-of-the-pipe" post treatment solutions. The "3R" (Recycle-Reduce-Reuse integrated environment control technology provides preventive pre-treatment of low grade solid fuels, such as brown coal and contaminated solid fuels to achieve high grade cleansed fuels with anthracite and coke comparable quality. The goal of the 3R technology is to provide cost efficient and environmentally sustainable solutions by preventive pre-treatment means for extended operations of the solid fuel combustion power plants with capacity up to 300 MWe power capacities. The 3R Anthracite Clean Coal end product and technology may advantageously be integrated to the oxyfuel-oxy-firing, Foster Wheeler anthracite arc-fired utility type boiler and Heat Pipe Reformer technologies in combination with CO2 capture and storage programs. The 3R technology is patented original solution. Advantages. Feedstock flexibility: application of pre-treated multi fuels from wider fuel selection and availability. Improved burning efficiency. Technology flexibility: efficient and advantageous inter-link to proven boiler technologies, such as oxyfuel and arcfired boilers. Near zero pollutants for hazardous-air-pollutants: preventive separation of halogens and heavy metals into small volume streams prior utilization of cleansed fuels. >97% organic sulphur removal achieved by the 3R thermal pre-treatment process. Integrated carbon capture and storage (CCS programs: the introduction of monolitic GHG gas is improving storage safety. The 3R technology offers significant improvements for the GHG CCS conditions. Cost reduction: decrease of overall production costs when all real costs are calculated. Improved safety: application of preventive measures. For pre-treatment a specific purpose designed, developed, and patented pyrolysis technology used, consisting of a horizontally arranged externally

Can a Clean-Air Heat Pump (CAHP) maintain air purification capability when using polluted air for regeneration?

DEFF Research Database (Denmark)

Sheng, Ying; Fang, Lei

2018-01-01

Clean Air Heat Pump (CAHP) was one type of rotary desiccant cooling system which combined a silica gel rotor with a heat pump to achieve air cleaning, dehumidifying and cooling in buildings. Using exhaust air from the conditioned room for regeneration of the silica gel rotor might have an advantage...... on reducing the regeneration air temperature and further improving the energy performance of the CAHP. However, the exhaust air carried a lot of indoor air pollutants. Whether using exhaust air for the regeneration of the silica gel rotor had an impact on the air cleaning performance of the CAHP...... was experimentally studied. The results showed that using the air contained acetone or toluene for regeneration reduced the pollutants removal capability of CAHP with a reduction of approx. 10% in air cleaning efficiency. The energy performance of the CAHP when using exhaust air for regeneration was also evaluated...

Heat transfer in a fuel pin shipping container

International Nuclear Information System (INIS)

Ingham, J.G.

1980-01-01

Maximum cladding temperatures occur when the IDENT 1578 fuel pin shipping container is installed in the T-3 Cask. The maximum allowable cladding temperature of 800 0 F is reached when the rate of energy deposited in the 19-pin basket reaches 400 watts. Since 45% of the energy which is generated in the fuel escapes the 19-pin basket without being deposited, mostly gamma energy, the maximum allowable rate of heat generation is 400/.55 = 727 watts. Similarly, the maximum allowable cladding temperature of 800 0 F is reached when the rate of energy deposited in the 40-pin basket reaches 465 watts. Since 33% of the energy which is generated in the fuel escapes the 40-pin basket without being deposited, mostly gamma energy, the maximum allowable rate of heat generation is 465/.66 = 704 watts. The IDENT 1578 fuel pin shipping container therefore meets its thermal design criteria. IDENT 1578 can handle fuel pins with a decay heat load of 600 watts while maintaining the maximum fuel pin cladding temperature below 800 0 F. The emissivities which were determined from the test results for the basket tubes and container are relatively low and correspond to new, shiny conditions. As the IDENT 1578 container is exposed to high temperatures for extended periods of time during the transportation of fuel pins, the emissivities will probably increase. This will result in reduced temperatures

Heat transfer and temperature distribution in fuel

International Nuclear Information System (INIS)

Katanic-Popovic, J.; Stevanovic, M.

1966-01-01

This paper describes methods and procedures for determining the integral, mean and effective heat conductivity and temperature distribution in fuel, with the experimental solutions for measuring these parameters. A procedure for measuring the integral conductivity by measuring the power generated in the fuel is given [sr

Power, heat and chilliness with natural gas - fuel cells and air conditioning

International Nuclear Information System (INIS)

Krein, Stephan; Ruehling, Karin

1999-01-01

A new and innovative concept of the supply with power, heat and chilliness will realise in the new Malteser-hospital in Kamenz. The core of this demonstration-plant are a fuel cell, an adsorption cooling machine as well as multi-solar collectors. The fuel cell has two goals. Primary it produces power for the own demand. The selected dimension guarantees, that the power will consume nearly continuously. Secondly the produced heat of the fuel cell (and the solar-heat too) will use for heating and preparation of warm water. In the summer, the heat will use for the adsorption cooling machine, which produces chilliness for air-conditioning. The advantage in the face of common concepts of combining power and heat is the high-efficiently use of the fuel-energy for electric power generation on the one hand. Fuel cells work with high efficiency also at partial load. On the other hand, with the adsorption cooling machine the produced heat of fuel cell and multi-solar collectors can be used also in the summer. First experiences with this concept show, that an optimised co-operation of the components with an adaptive, self-learning control system based on the weather forecast as well as various storages for heat and chilliness can be achieve. A continuously operation, high fuel utilisation and reduced environmental pollution can be demonstrated. (author)

Post-accident fuel relocation and heat removal in the LMFBR

International Nuclear Information System (INIS)

Kazimi, M.S.; Tsai, S.S.; Gasser, R.D.

1976-08-01

Assessment of the dynamics of post-accident fuel relocation and heat removal is an important aspect of the evaluation of the consequences of a hypothetical accident in an LMFBR. Such an assessment is of particular importance in the evaluation of the post-accident radiological doses around the reactor site. In the present evaluation particular attention is given to the design features of the Clinch River Breeder Reactor Plant (CRBR). Fuel relocation and heat removal, assuming certain conditions have resulted in core disruption, are discussed. The discussion of events and phenomena involved in the relocation processes is centered around the resulting patterns of heat source distribution. The factors influencing fuel relocation and distribution in the inlet and outlet plena of the reactor vessel are discussed. The current technology of in-vessel heat removal is applied to the design of the CRBR reactor. Both fuel debris cooling limits and overall coolant flow in the reactor under natural convection conditions are explored. Some of the uncertainties in ex-vessel fuel behavior are addressed. In particular, the effect of melting the cavity bed on the rate of growth of a molten fuel pool is investigated

National Clean Fleets Partnership (Fact Sheet)

Energy Technology Data Exchange (ETDEWEB)

2012-01-01

Provides an overview of Clean Cities National Clean Fleets Partnership (NCFP). The NCFP is open to large private-sector companies that have fleet operations in multiple states. Companies that join the partnership receive customized assistance to reduce petroleum use through increased efficiency and use of alternative fuels. This initiative provides fleets with specialized resources, expertise, and support to successfully incorporate alternative fuels and fuel-saving measures into their operations. The National Clean Fleets Partnership builds on the established success of DOE's Clean Cities program, which reduces petroleum consumption at the community level through a nationwide network of coalitions that work with local stakeholders. Developed with input from fleet managers, industry representatives, and Clean Cities coordinators, the National Clean Fleets Partnership goes one step further by working with large private-sector fleets.

Wood as a home heating fuel

International Nuclear Information System (INIS)

Wood, K.

1991-01-01

This article describes the development of clean-burning technology in three types of wood-burning appliances: catalytic, non-catalytic, and pellet stoves. A recent study by the Washington State Energy Extension Office concluded that in homes that use both electricity and wood, 73 megawatts of electricity/yr were saved by using wood. Since wood-burning stoves can now meet air quality standards, wood could be considered to be a greenhouse-neutral fuel if more trees are planted as they are consumed

Fuel fired heat sources

Energy Technology Data Exchange (ETDEWEB)

Ortlinghaus, U

1977-09-08

Fuel fired heat sources with a valve-controlled ignition and main burner, whose flame is monitored and whose control valve is closed or opened by a controller according to the control deviation between actual and reference heat source temperature, previously suffered the disadvantage of high consumption of ignition gas. According to the invention this disadvantage is avoided by closing the ignition valve from the controller via a delay unit and having the delay time of the delay unit controlled either by the temperature measured by the sensor or increasing it with increasing deviation of the actual value of pre-temperature from the reference value of the pre-temperature.

Heat and radiation analysis of NPP Krsko irradiated fuel

International Nuclear Information System (INIS)

Lalovic, M.

1986-01-01

Radioactive and heat potential for irradiated fuel in the region 2 with burnup of 13400 MWd/tHM, and in the region 4A with burnup of 9360 MWd/tHM for NPP KRSKO, was calculated. Computer code KORIGEN (Karlsruhe Oak Ridge Isotope Generation and Depletion Code) was used. The aspects of radiation (mainly gamma and neutrons) and of heat production was considered with respect to their impact on fuel handing and waste management. Isotopic concentrations for irradiated fuel was calculated and compared with Westinghouse data. (author)

Hydrogen Storage Experiments for an Undergraduate Laboratory Course--Clean Energy: Hydrogen/Fuel Cells

Science.gov (United States)

Bailey, Alla; Andrews, Lisa; Khot, Ameya; Rubin, Lea; Young, Jun; Allston, Thomas D.; Takacs, Gerald A.

2015-01-01

Global interest in both renewable energies and reduction in emission levels has placed increasing attention on hydrogen-based fuel cells that avoid harm to the environment by releasing only water as a byproduct. Therefore, there is a critical need for education and workforce development in clean energy technologies. A new undergraduate laboratory…

Calculation of the fuel temperature field under heat release and heat conductance transient conditions

International Nuclear Information System (INIS)

Kazakov, E.K.; Chernukhina, G.M.

1974-01-01

Results of calculation of the temperature distribution in an annular fuel element at transient thermal conductivity and heat release values are given. The calculation has been carried out by the mesh technique with the third-order boundary conditions for the inner surface assumed and with heat fluxes and temperatures at the zone boundaries to be equal. Three variants of solving the problem of a stationary temperature field are considered for failed fuel elements with clad flaking or cracks. The results obtained show the nonuniformity of the fuel element temperature field to depend strongly on the perturbation parameter at transient thermal conductivity and heat release values. In case of can flaking at a short length, the core temperature rises quickly after flaking. While evaluating superheating, one should take into account the symmetry of can flaking [ru

Clean Cities Fact Sheet

Energy Technology Data Exchange (ETDEWEB)

2004-01-01

This fact sheet explains the Clean Cities Program and provides contact information for all coalitions and regional offices. It answers key questions such as: What is the Clean Cities Program? What are alternative fuels? How does the Clean Cities Program work? What sort of assistance does Clean Cities offer? What has Clean Cities accomplished? What is Clean Cities International? and Where can I find more information?

Converting environmentally hazardous materials into clean energy using a novel nanostructured photoelectrochemical fuel cell

Energy Technology Data Exchange (ETDEWEB)

Gan, Yong X., E-mail: yong.gan@utoledo.edu [Department of Mechanical, Industrial and Manufacturing Engineering, College of Engineering, University of Toledo, Toledo, OH 43606 (United States); Gan, Bo J. [Ottawa Hills High School, 2532 Evergreen Road, Toledo, OH 43606 (United States); Clark, Evan; Su, Lusheng [Department of Mechanical, Industrial and Manufacturing Engineering, College of Engineering, University of Toledo, Toledo, OH 43606 (United States); Zhang, Lihua [Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973 (United States)

2012-09-15

Highlights: ► A photoelectrochemical fuel cell has been made from TiO{sub 2} nanotubes. ► The fuel cell decomposes environmentally hazardous materials to produce electricity. ► Doping the anode with a transition metal oxide increases the visible light sensitivity. ► Loading the anode with a conducting polymer enhances the visible light absorption. -- Abstract: In this work, a novel photoelectrochemical fuel cell consisting of a titanium dioxide nanotube array photosensitive anode and a platinum cathode was made for decomposing environmentally hazardous materials to produce electricity and clean fuel. Titanium dioxide nanotubes (TiO{sub 2} NTs) were prepared via electrochemical oxidation of pure Ti in an ammonium fluoride and glycerol-containing solution. Scanning electron microscopy was used to analyze the morphology of the nanotubes. The average diameter, wall thickness and length of the as-prepared TiO{sub 2} NTs were determined. The photosensitive anode made from the highly ordered TiO{sub 2} NTs has good photo-catalytic property, as proven by the decomposition tests on urea, ammonia, sodium sulfide and automobile engine coolant under ultraviolet (UV) radiation. To improve the efficiency of the fuel cell, doping the TiO{sub 2} NTs with a transition metal oxide, NiO, was performed and the photosensitivity of the doped anode was tested under visible light irradiation. It is found that the NiO-doped anode is sensitive to visible light. Also found is that polyaniline-doped photosensitive anode can harvest photon energy in the visible light spectrum range much more efficiently than the NiO-doped one. It is concluded that the nanostructured photoelectrochemical fuel cell can generate electricity and clean fuel by decomposing hazardous materials under sunlight.

Measuring method for heat-shrinkage of fuel pellet

International Nuclear Information System (INIS)

Komono, Akira; Ishizaki, Jin; Inaki, Kiyohiro.

1997-01-01

The present invention concerns a method of determining an amount of heat-shrinkage of UR 2 pellets containing gadolinium oxide (Gd 2 O 2 ) based on the difference of the density thereof before and after heating. In a heat shrinkage test of UO 2 pellets containing from 1.0 to 15.0% by weight of gadolinium oxide, the amount of heat-shrinkage is measured under the condition of heat-retaining temperature: from 1700 to 1750degC, temperature elevation time and lowering time: from 90 to 120mins, heat-retaining time: 24hours, inert gas atmosphere, gas pressure: 0.35kg/cm 2 and gas dew point: from -55 to 40degC without changing O/M. This invention has a feature in the use of the inert gas and the elevation of the dew point of the gas. Then, oxygen dissociation phenomenon from crystal lattices of the fuel pellets is suppressed, and normal densification value is shown. Then, fuel pellets of good quality with less fluctuation of the heat-shrinkage can be obtained. (N.H.)

Effect of Air Cleaning Technologies in Conjunction With the Use of Rotary Heat Exchangers in Residential Buildings

DEFF Research Database (Denmark)

Afshari, Alireza; Bergsøe, Niels Christian; Ekberg, Lars

2013-01-01

This study is part of a research project concerning the possibilities of applying efficient air cleaning technologies using rotary heat exchanger in residential buildings. The purpose of this project was to identify and adapt new air-cleaning technologies for implementation in HVAC systems...... with rotary air-to-air heat exchangers. For this purpose, a mechanical filter with low pressure drop and a 4 cm thick activated carbon filter were selected for testing in a laboratory environment. The measurements included testing of the filters, separately and combined, in a ductwork to study the efficiency...

Induction Heating Model of Cermet Fuel Element Environmental Test (CFEET)

Science.gov (United States)

Gomez, Carlos F.; Bradley, D. E.; Cavender, D. P.; Mireles, O. R.; Hickman, R. R.; Trent, D.; Stewart, E.

2013-01-01

Deep space missions with large payloads require high specific impulse and relatively high thrust to achieve mission goals in reasonable time frames. Nuclear Thermal Rockets (NTR) are capable of producing a high specific impulse by employing heat produced by a fission reactor to heat and therefore accelerate hydrogen through a rocket nozzle providing thrust. Fuel element temperatures are very high (up to 3000 K) and hydrogen is highly reactive with most materials at high temperatures. Data covering the effects of high-temperature hydrogen exposure on fuel elements are limited. The primary concern is the mechanical failure of fuel elements due to large thermal gradients; therefore, high-melting-point ceramics-metallic matrix composites (cermets) are one of the fuels under consideration as part of the Nuclear Cryogenic Propulsion Stage (NCPS) Advance Exploration System (AES) technology project at the Marshall Space Flight Center. The purpose of testing and analytical modeling is to determine their ability to survive and maintain thermal performance in a prototypical NTR reactor environment of exposure to hydrogen at very high temperatures and obtain data to assess the properties of the non-nuclear support materials. The fission process and the resulting heating performance are well known and do not require that active fissile material to be integrated in this testing. A small-scale test bed; Compact Fuel Element Environmental Tester (CFEET), designed to heat fuel element samples via induction heating and expose samples to hydrogen is being developed at MSFC to assist in optimal material and manufacturing process selection without utilizing fissile material. This paper details the analytical approach to help design and optimize the test bed using COMSOL Multiphysics for predicting thermal gradients induced by electromagnetic heating (Induction heating) and Thermal Desktop for radiation calculations.

Influence of Fuel Meat Porosity on Heat Capacities of Fuel Element Plate U3Si2-Al

International Nuclear Information System (INIS)

Ginting, Aslina Br.; Supardjo; Sutri Indaryati

2007-01-01

Analyze of heat capacities of Al powder, AIMg 2 cladding, U 3 Si 2 powder and PEB U 3 Si 2 -Al with the meat porosity of 4.9; 5.53 ; 6.25 ; 6.95 %; 7.90; 8.66% have been done. Analysis was conducted by using Differential Scanning Calorimeter (DSC) at temperature 30℃ to 450℃ with heating rate 1℃ /minute in Argon gas media. The purpose of analyze is to know the influence of increasing of fuel meat porosity on heat capacities because increasing of percentage of meat porosity will cause degradation the of heat capacities of PEB U 3 Si 2 -Al. Result of analysis showed that the heat capacities of Al powder, AIMg 2 cladding increase by temperature, while heat capacities of U 3 Si 2 powder was stable with increasing of temperature up to 450℃. Analysis of heat capacities toward PEB U 3 Si 2 -Al indicate that increasing of fuel meat porosity of caused degradation of the heat capacities of PEB U 3 Si 2 -Al. Data obtained were expected to serve the purpose of input to fabricator of research reactor fuel in for design of fuel element type silicide with high loading. (author)

Having a Son Promotes Clean Cooking Fuel Use in Urban India: Women's Status and Son Preference

OpenAIRE

Avinash Kishore; Dean Spears

2014-01-01

Urban Indian households with a male first child are approximately 2 percentage points more likely to use clean cooking fuel than comparable households with a female first child. Given Indian son preference, there are at least two mechanisms by which child sex could affect fuel choice: by improving the intrahousehold status of women, who bear more of the costs of traditional fuels, or by presenting an opportunity to invest in children's health, in the context of a preference for healthier boys...

Characteristics of fuel CRUD from Ringhals Unit 4. A comparison of CRUD samples from ultrasonic fuel cleaning and fuel scrape

International Nuclear Information System (INIS)

Chen, Jiaxin; Eskhult, Jonas; Marks, Chuck; Dingee, John; Bengtsson, Bernt; Wells, Daniel

2014-01-01

The characteristics and behaviour of PWR fuel CRUD are closely related to plant radiation field build-up and the risks of CRUD-Induced Power Shifts (CIPS, previously AOA) and CRUD-Induced Localized Corrosion (CILC). At Ringhals NPP fuel scrape technology has frequently been used to collect fuel CRUD samples as a part of plant water chemistry monitoring programs. In 2012, high efficiency ultrasonic fuel cleaning (HE-UFC) technology was first used at Ringhals Unit 4 to reduce the risk of CIPS, which was expected to increase due to steam generator replacement and a subsequent power uprate. In the HE-UFC system a “first-of-a-kind” CRUD sampling system was installed for collecting fuel CRUD. It is of interest to compare the fuel CRUD samples collected by the two different CRUD sampling methods and to understand if HE-UFC crud sampling could be used to replace or supplement the fuel scrape method. This paper presents some preliminary results on isotopic compositions, elemental compositions, and phase compositions of fuel CRUD samples collected from similar fuel rods and assemblies by both methods during the 2012 refueling outage, one cycle after steam generator replacement at Ringhals Unit 4. The results show that the characteristics of fuel CRUD sampled by HE-UFC and fuel scrape, although not always identical, were similar or correlated to some extent in terms of weight ratios of Ni to Fe and Cr to Fe as well as specific activities of Co-58, Co-60 and Cr-51. However, due to the limited experience with the HE-UFC sampling method, more consideration is required if the statistical significance of the obtained data and indications are to be verified. (author)

Transient heat conduction in a pebble fuel applying fractional model

International Nuclear Information System (INIS)

Gomez A, R.; Espinosa P, G.

2009-10-01

In this paper we presents the equation of thermal diffusion of temporary-fractional order in the one-dimensional space in spherical coordinates, with the objective to analyze the heat transference between the fuel and coolant in a fuel element of a Pebble Bed Modular Reactor. The pebble fuel is the heterogeneous system made by microsphere constitutes by U O, pyrolytic carbon and silicon carbide mixed with graphite. To describe the heat transfer phenomena in the pebble fuel we applied a constitutive law fractional (Non-Fourier) in order to analyze the behaviour transient of the temperature distribution in the pebble fuel with anomalous thermal diffusion effects a numerical model is developed. (Author)

Modeling of the heat transfer performance of plate-type dispersion nuclear fuel elements

Science.gov (United States)

Ding, Shurong; Huo, Yongzhong; Yan, XiaoQing

2009-08-01

Considering the mutual actions between fuel particles and the metal matrix, the three-dimensional finite element models are developed to simulate the heat transfer behaviors of dispersion nuclear fuel plates. The research results indicate that the temperatures of the fuel plate might rise more distinctly with considering the particle swelling and the degraded surface heat transfer coefficients with increasing burnup; the local heating phenomenon within the particles appears when their thermal conductivities are too low. With rise of the surface heat transfer coefficients, the temperatures within the fuel plate decrease; the temperatures of the fuel plate are sensitive to the variations of the heat transfer coefficients whose values are lower, but their effects are weakened and slight when the heat transfer coefficients increase and reach a certain extent. Increasing the heat generation rate leads to elevating the internal temperatures. The temperatures and the maximum temperature differences within the plate increase along with the particle volume fractions. The surface thermal flux goes up along with particle volume fractions and heat generation rates, but the effects of surface heat transfer coefficients are not evident.

A proposed Regulatory Guide basis for spent fuel decay heat

International Nuclear Information System (INIS)

Hermann, O.W.; Parks, C.V.; Renier, J.P.

1991-01-01

A proposed revision to Regulatory Guide 3.54, ''Spent Fuel Heat Generation in an Independent Spent Fuel Storage Installation'' has been developed for the US Nuclear Regulatory Commission. The proposed revision includes a data base of decay heat rates calculated as a function of burnup, specific power, cooling time, initial fuel 235 U enrichment and assembly type (i.e., PWR or BWR). Validation of the calculational method was done by comparison with existing measured decay heat rates. Procedures for proper use of the data base, adjustment formulae accounting for effects due to differences in operating history and initial enrichment, and a defensible safety factor were derived. 15 refs., 6 tabs

Towards a Future of District Heating Systems with Low-Temperature Operation together with Non-Fossil Fuel Heat Sources

DEFF Research Database (Denmark)

Tol, Hakan; Dinçer, Ibrahim; Svendsen, Svend

2012-01-01

This study focused on investigation of non-fossil fuel heat sources to be supplied to low-energy district heating systems operating in low temperature such as 55 C and 25 C in terms of, respectively, supply and return. Vast variety of heat sources classed in categories such as fossil fuel...

46 CFR 147.50 - Fuel for cooking, heating, and lighting.

Science.gov (United States)

2010-10-01

... cargo vessels. (b) Fluid alcohol is prohibited for cooking, heating, or lighting on ferry vessels. Fluid... 46 Shipping 5 2010-10-01 2010-10-01 false Fuel for cooking, heating, and lighting. 147.50 Section... SHIPS' STORES Stowage and Other Special Requirements for Particular Materials § 147.50 Fuel for cooking...

Utilisation of heat and pressure through the whole fuel cycle

International Nuclear Information System (INIS)

Eddowes, T.; Moricca, S.; Webb, N.

2003-01-01

Full text: The existence of the earth around us is a result of heat and pressure combined to form the very crust we stand on. With such a good model, scientists working throughout the nuclear fuel cycle have used these principles to optimise each particular step. From the fabrication of fuel rods and running of reactors to the final storage of the waste generated; heat and pressure have proved to be vital resources. At ANSTO the concepts of using heat and pressure to consolidate the waste produced for the nuclear fuel cycle have been extensively investigated. Working with collaborators, it has been demonstrated that the intermediate to high level waste can be incorporated into a ceramic or glass-ceramic matrix and immobilised therein, using heat and pressure via the means of a Hot Isostatic Press. This paper touches on how following the simple principles of heat and pressure utilised in the operation of this planet every day, the nuclear fuel cycle can be most efficient. The main focus has been the utilisation of Hot Isostatic Pressing for the production of various durable wasteforms at ANSTO for both Australian and international wastes

Heat transfer investigations within dry spent fuel casks

International Nuclear Information System (INIS)

Nitsche, F.

1986-07-01

For studying the heat transfer processes and predicting the maximum spent fuel element surface temperature in a spent fuel assembly (SFA) transported in a dry cask, model experiments have been performed with a gas-filled model cask containing a simplified electrically heated model of a WWER-type SFA with 90 fuel elements. The temperature distribution of the SFA model is measured for different heat rates under vacuum in the model cask, and under normal pressure and overpressure (0.1 ... 0.7 MPa) for several cooling gases (air, argon, helium) in order to separately investigate heat transfer processes by radiation and convection/conduction. The measuring results were compared with the calculations. Computer programmes as well as simplified calculation methods for temperature prediction were developed and checked. The results obtained are also useful for thermal analyses in the field of the dry storage of SFAs in a cask or can. Specifically it was found that: The heat removal from the SFA can be considerably improved by increasing the internal cask pressure or by using helium as coolant. The radiant heat exchange in the SFA model can be calculated with sufficient accuracy by means of a computer programme developed in 1978 or by means of a simplified analytical representation shown in the final report. Both methods are directly applicable to the original SFA and useful in order to approximately calculate the maximum SFE surface temperature under normal pressure, if the fraction of heat transferred by radiation is allowed for. For the calculation of the total heat transfer a computer programme was developed and verified, which completely permits the temperature prediction of the SFA model in dependence on heat rate, type of gaseous coolant and coolant pressure. This computer programme can be directly applied to the original SFA for the calculation of the maximum SFE surface temperature

The fuel to clad heat transfer coefficient in advanced MX-type fuel pins

International Nuclear Information System (INIS)

Caligara, F.; Campana, M.; Mandler, R.; Blank, H.

1979-01-01

Advanced fuels (mixed carbides, nitrides and carbonitrides) are characterised by a high thermal conductivity compared to that of oxide fuels (5 times greater) and their behaviour under irradiation (amount of swelling, fracture behaviour, restructuring) is far more sensitive to the design parameters and to the operating temperature than that of oxide fuels. The use of advanced fuels is therefore conditioned by the possibility of mastering the above phenomena, and the full exploitation of their favorable neutron characteristics depends upon a good understanding of the mutual relationships of the various parameters, which eventually affect the mechanical stability of the pin. By far the most important parameter is the radial temperature profile which controls the swelling of the fuel and the build-up of stress fields within the pin. Since the rate of fission gas swelling of these fuels is relatively large, a sufficient amount of free space has to be provided within the pin. This space originally appears as fabrication porosity and as fuel-to-clad clearance. Due to the large initial gap width and to the high fuel thermal conductivity, the range of the fuel operating temperatures is mainly determined by the fuel-to-clad heat transfer coefficient h, whose correct determination becomes one of the central points in modelling. During the many years of modelling activity in the field of oxide fuels, several theoretical models have been developed to calculate h, and a large amount of experimental data has been produced for the empirical adjustment of the parameters involved, so that the situation may be regarded as rather satisfactory. The analysis lead to the following conclusions. A quantitative comparison of experimental h-values with existing models for h requires rather sophisticated instrumented irradiation capsules, which permit the measurement of mechanical data (concerning fuel and clad) together with heat rating and temperatures. More and better well

Applying Thermodynamics to Fossil Fuels: Heats of Combustion from Elemental Compositions.

Science.gov (United States)

Lloyd, William G.; Davenport, Derek A.

1980-01-01

Discussed are the calculations of heats of combustions of some selected fossil fuel compounds such as some foreign shale oils and United States coals. Heating values for coal- and petroleum-derived fuel oils are also presented. (HM)

Heat planning for fossil-fuel-free district heating areas with extensive end-use heat savings: A case study of the Copenhagen district heating area in Denmark

International Nuclear Information System (INIS)

Harrestrup, M.; Svendsen, S.

2014-01-01

The Danish government plans to make the Danish energy system to be completely free of fossil fuels by 2050 and that by 2035 the energy supply for buildings and electricity should be entirely based on renewable energy sources. To become independent from fossil fuels, it is necessary to reduce the energy consumption of the existing building stock, increase energy efficiency, and convert the present heat supply from fossil fuels to renewable energy sources. District heating is a sustainable way of providing space heating and domestic hot water to buildings in densely populated areas. This paper is a theoretical investigation of the district heating system in the Copenhagen area, in which heat conservation is related to the heat supply in buildings from an economic perspective. Supplying the existing building stock from low-temperature energy resources, e.g. geothermal heat, might lead to oversized heating plants that are too expensive to build in comparison with the potential energy savings in buildings. Long-term strategies for the existing building stock must ensure that costs are minimized and that investments in energy savings and new heating capacity are optimized and carried out at the right time. - Highlights: • We investigate how much heating consumption needs to be reduced in a district heating area. • We examine fossil-fuel-free supply vs. energy conservations in the building stock. • It is slightly cost-beneficial to invest in energy renovation from today for a societal point of view. • It is economically beneficial for district heating companies to invest in energy renovations from today. • The cost per delivered heat unit is lower when energy renovations are carried out from today

Combined Heat and Power Market Potential for Opportunity Fuels

Energy Technology Data Exchange (ETDEWEB)

Jones, David [Resource Dynamics Corporation, McLean, VA (United States); Lemar, Paul [Resource Dynamics Corporation, McLean, VA (United States

2015-12-01

This report estimates the potential for opportunity fuel combined heat and power (CHP) applications in the United States, and provides estimates for the technical and economic market potential compared to those included in an earlier report. An opportunity fuel is any type of fuel that is not widely used when compared to traditional fossil fuels. Opportunity fuels primarily consist of biomass fuels, industrial waste products and fossil fuel derivatives. These fuels have the potential to be an economically viable source of power generation in various CHP applications.

Transient heating and evaporation of moving fuel droplets

DEFF Research Database (Denmark)

Yin, Chungen

2014-01-01

In combustion devices involving direct injection of low-volatility liquid fuel (e.g., bio-oils from pyrolysis process) into the combustor, transient heating and vaporization is an important controlling factor in ignition and combustion of the fuel vapor/air mixture. As a result, quite many...... experimental and numerical efforts have been made on this topic. In this paper, a comprehensive 3D model that addresses the internal circulation, heat and mass transfer within a moving droplet has been successfully developed. The model is calibrated by analytical solutions for simplified cases and validated...

APPLICATIONS OF THERMAL ENERGY STORAGE TO WASTE HEAT RECOVERY IN THE FOOD PROCESSING INDUSTRY, Final Report

Energy Technology Data Exchange (ETDEWEB)

Lundberg, W. L.; Christenson, James A.

1979-07-31

A project is discussed in which the possibilities for economical waste heat recovery and utilization in the food industry were examined. Waste heat availability and applications surveys were performed at two manufacturing plants engaged in low temperature (freezing) and high temperature (cooking, sterilizing, etc.) food processing. The surveys indicate usable waste heat is available in significant quantities which could be applied to existing, on-site energy demands resulting in sizable reductions in factory fuel and energy usage. At the high temperature plant, the energy demands involve the heating of fresh water for boiler make-up, for the food processes and for the daily clean-up operation. Clean-up poses an opportunity for thermal energy storage since waste heat is produced during the one or two production shifts of each working day while the major clean-up effort does not occur until food production ends. At the frozen food facility, the clean-up water application again exists and, in addition, refrigeration waste heat could also be applied to warm the soil beneath the ground floor freezer space. Systems to recover and apply waste heat in these situations were developed conceptually and thermal/economic performance predictions were obtained. The results of those studies indicate the economics of waste heat recovery can be attractive for facilities with high energy demand levels. Small factories, however, with relatively low energy demands may find the economics marginal although, percentagewise, the fuel and energy savings are appreciable.

Fuel cycle related parametric study considering long lived actinide production, decay heat and fuel cycle performances

International Nuclear Information System (INIS)

Raepsaet, X.; Damian, F.; Lenain, R.; Lecomte, M.

2001-01-01

One of the very attractive HTGR reactor characteristics is its highly versatile and flexible core that can fulfil a wide range of diverse fuel cycles. Based on a GTMHR-600 MWth reactor, analyses of several fuel cycles were carried out without taking into account common fuel particle performance limits (burnup, fast fluence, temperature). These values are, however, indicated in each case. Fuel derived from uranium, thorium and a wide variety of plutonium grades has been considered. Long-lived actinide production and total residual decay heat were evaluated for the various types of fuel. The results presented in this papers provide a comparison of the potential and limits of each fuel cycle and allow to define specific cycles offering lowest actinide production and residual heat associated with a long life cycle. (author)

Clean Cities Now, Vol. 18, No. 2

Energy Technology Data Exchange (ETDEWEB)

None

2015-01-19

This is version 18.2 of Clean Cities Now, the official biannual newsletter of the Clean Cities program. Clean Cities is an initiative designed to reduce petroleum consumption in the transportation sector by advancing the use of alternative and renewable fuels, fuel economy improvements, idle-reduction measures, and new technologies, as they emerge.

Vernotte-Cattaneo approximation for heat conduction in fuel rod

International Nuclear Information System (INIS)

Espinosa P, G.; Espinosa M, E. G.

2009-10-01

In this paper we explore the applicability of a fuel rod mathematical model based on the Vernotte-Cattaneo transient heat conduction as constitutive law (Non-Fourier approach) for light water reactors transient analysis. In the classical theory of diffusion, the Fourier law of heat conduction is used to describe the relation between the heat conduction is used to describe the relation between the heat flux vector and the temperature gradient assuming that the heat propagation speeds are infinite. The motivation for this research was to eliminate the paradox of an infinite. The motivation for this research was to eliminate the paradox of an infinite thermal wave speed. The time-dependent heat sources were considered in the fuel rod heat transfer model. The close of the main steam isolated valves transient in a boiling water reactor was analyzed for different relaxation times. The results show that for long-times the heat fluxes on the clad surface under Vernotte-Cattaneo approach can be important, while for short-times and from the engineering point of view the changes are very small. (Author)

Radial heat transfer from fuel to moderator during LOCAs for CANDU PHW reactors

International Nuclear Information System (INIS)

Hildebrandt, J.G.; So, C.B.; Gillespie, G.E.; MacLean, G.

1983-01-01

In a postulated CANDU-PHW loss-of-coolant accident (LOCA) with coincident impaired emergency cooling, the axial transport of heat from the fuel by convection is reduced. This reduction in heat removal causes the fuel to heat up and the radial heat transfer to the moderator to become significant. This paper deals with two codes that predict the thermal response of fuel channels under LOCA conditions. New channel thermal radiation models in both RAMA, a thermalhydraulic code, and CHAN II, a fuel channel thermo-chemical code, are presented and their predictions are compared with the experimental results of an electrically heated bundle of 37 fuel pins. A second experiment, involving a single heated pin in a channel with flowing steam, is presented. The predictions of RAMA and CHAN II are compared with this experiment to verify the codes' thermo-chemical models. There is good agreement between the predictions of both codes and the experimental results

What is Clean Cities? October 2011 (Brochure)

Energy Technology Data Exchange (ETDEWEB)

2011-10-01

Brochure describes the Clean Cities program and includes the contact information for its 85 coalitions. Sponsored by the U.S. Department of Energy's (DOE) Vehicle Technologies Program (VTP), Clean Cities is a government-industry partnership that reduces petroleum consumption in the transportation sector. Clean Cities contributes to the energy, environmental, and economic security of the United States by supporting local decisions to reduce our dependence on imported petroleum. Established in 1993 in response to the Energy Policy Act (EPAct) of 1992, the partnership provides tools and resources for voluntary, community-centered programs to reduce consumption of petroleum-based fuels. In nearly 100 coalitions, government agencies and private companies voluntarily come together under the umbrella of Clean Cities. The partnership helps all parties identify mutual interests and meet the objectives of reducing the use of petroleum, developing regional economic opportunities, and improving air quality. Clean Cities deploys technologies and practices developed by VTP. These include idle-reduction equipment, electric-drive vehicles, fuel economy measures, and renewable and alternative fuels, such as natural gas, liquefied petroleum gas (propane), electricity, hydrogen, biofuels, and biogas. Idle-reduction equipment is targeted primarily to buses and heavy-duty trucks, which use more than 2 billion gallons of fuel every year in the United States while idling. Clean Cities fuel economy measures include public education on vehicle choice and fuel-efficient driving practices.

Fuel cells for electricity generation from carbonaceous fuels

Energy Technology Data Exchange (ETDEWEB)

Ledjeff-Hey, K; Formanski, V; Roes, J [Gerhard-Mercator- Universitaet - Gesamthochschule Duisburg, Fachbereich Maschinenbau/Fachgebiet Energietechnik, Duisburg (Germany); Heinzel, A [Fraunhofer Inst. for Solar Energy Systems (ISE), Freiburg (Germany)

1998-09-01

Fuel cells, which are electrochemical systems converting chemical energy directly into electrical energy with water and heat as by-products, are of interest as a means of generating electricity which is environmentally friendly, clean and highly efficient. They are classified according to the electrolyte used. The main types of cell in order of operating temperature are described. These are: alkaline fuel cells, the polymer electrolyte membrane fuel cell (PEMFC); the phosphoric acid fuel cell (PAFC); the molten carbonate fuel cell (MCFC); the solid oxide fuel cell (SOFC). Applications depend on the type of cell and may range from power generation on a large scale to mobile application in cars or portable systems. One of the most promising options is the PEM-fuel cell stack where there has been significant improvement in power density in recent years. The production from carbonaceous fuels and purification of the cell fuel, hydrogen, is considered. Of the purification methods available, hydrogen separation by means of palladium alloy membranes seems particular effective in reducing CO concentrations to the low levels required for PEM cells. (UK)

Reduction of repository heat load using advanced fuel cycles

International Nuclear Information System (INIS)

Preston, Jeff; Miller, L.F.

2008-01-01

With the geologic repository at Yucca Mountain already nearing capacity full before opening, advanced fuel cycles that introduce reprocessing, fast reactors, and temporary storage sites have the potential to allow the repository to support the current reactor fleet and future expansion. An uncertainty analysis methodology that combines Monte Carlo distribution sampling, reactor physics data simulation, and neural network interpolation methods enable investigation into the factor reduction of heat capacity by using the hybrid fuel cycle. Using a Super PRISM fast reactor with a conversion ratio of 0.75, burn ups reach up to 200 MWd/t that decrease the plutonium inventory by about 5 metric tons every 12 years. Using the long burn up allows the footprint of 1 single core loading of FR fuel to have an integral decay heat of about 2.5x10 5 MW*yr over a 1500 year period that replaces the footprint of about 6 full core loadings of LWR fuel for the number of years required to fuel the FR, which have an integral decay heat of about.3 MW*yr for the same time integral. This results in an increase of a factor of 4 in repository support capacity from implementing a single fast reactor in an equilibrium cycle. (authors)

Clean Energy for Development: The Environmental and Socioeconomic Benefits of Ethanol as a Household Cooking Fuel In Ethiopia.

Energy Technology Data Exchange (ETDEWEB)

Debebe, M.; Lambe, F. (Gaia Association, Bole Subcity, P.O.Box 13493, Addis Ababa (Ethiopia)). e-mail: gaiaassociation@ethionet.et

2008-10-15

The overwhelming dependence of the household sector on traditional fuels (solid biomass) and kerosene for cooking is having a hugely negative impact on health, the environment and the economy in Ethiopia. Greenhouse gas (GHG) emissions and deforestation associated with harvesting biomass for cooking, are contributing to climate change and environmental degradation. Moreover, indoor air pollution from the burning of traditional fuels indoors causes numerous serious health problems for those exposed - in most cases, women and children. Ethiopian families cook using these fuels because they have no alternatives. Gaia Association, an Ethiopian NGO, and its partners are working to increase access to ethanol fuelled cooking stoves for households at all income levels and have conducted an extensive pilot study to assess the impact of the ethanol fuelled CleanCook stove on Ethiopian homes in a variety of locations. The favourable study results were used to inform a detailed business plan outlining the strategies for local commercialisation of the stove and fuel. Adoption of this alternative clean cooking technology has been shown to address the health, environmental and socioeconomic problems associated with heavy reliance on traditional cooking fuels.

Calculation of Heat-Bearing Agent’s Steady Flow in Fuel Bundle

Science.gov (United States)

Amosova, E. V.; Guba, G. G.

2017-11-01

This paper introduces the result of studying the heat exchange in the fuel bundle of the nuclear reactor’s fuel magazine. The article considers the fuel bundle of the infinite number of fuel elements, fuel elements are considered in the checkerboard fashion (at the tops of a regular triangle a fuel element is a plain round rod. The inhomogeneity of volume energy release in the rod forms the inhomogeneity of temperature and velocity fields, and pressure. Computational methods for studying hydrodynamics in magazines and cores with rod-shape fuel elements are based on a significant simplification of the problem: using basic (averaged) equations, isobaric section hypothesis, porous body model, etc. This could be explained by the complexity of math description of the three-dimensional fluid flow in the multi-connected area with the transfer coefficient anisotropy, curved boundaries and technical computation difficulties. Thus, calculative studying suggests itself as promising and important. There was developed a method for calculating the heat-mass exchange processes of inter-channel fuel element motions, which allows considering the contribution of natural convection to the heat-mass exchange based on the Navier-Stokes equations and Boussinesq approximation.

Direct electrical heating of irradiated metal fuel

International Nuclear Information System (INIS)

Fenske, G.R.; Emerson, J.E.; Savoie, F.E.; Johanson, E.W.

1985-01-01

The Integral Fast Reactor (IFR) concept proposed by Argonne National Laboratory utilizes a metal fuel core. Reactor safety analysis requires information on the potential for fuel axial expansion during severe thermal transients. In addition to a comparatively large thermal expansion coefficient, metallic fuel has a unique potential for enhanced pre-failure expansion driven by retained fission gas and ingested bond sodium. In this paper, the authors present preliminary results from three direct electrical heating (DEH) experiments performed on irradiated metal fuel to investigate axial expansion behavior. The test samples were from Experimental Breeder Reactor II (EBR-II) driver fuel ML-11 irradiated to 8 at.% burnup. Preliminary analysis of the results suggest that enhanced expansion driven by trapped fission gas can occur

Sensitivity Analysis of Gap Conductance for Heat Split in an Annular Fuel Rod

International Nuclear Information System (INIS)

Chun, Kun Ho; Chun, Tae Hyun; In, Wang Kee; Song, Keun Woo

2006-01-01

To increase of the core power density in the current PWR cores, an annular fuel rod was proposed by MIT. This annular fuel rod has two coolant channels and two cladding-pellet gaps unlike the current solid fuel rod. It's important to predict the heat split reasonably because it affects coolant enthalpy rise in each channel and Departure from Nuclear Boiling Ratio (DNBR) in each channel. Conversely, coolant conditions affect fuel temperature and heat split. In particular if the heat rate leans to either inner or outer channel, it is out of a thermal equilibrium. To control a thermal imbalance, placing another gap in the pellet is introduced. The heat flow distribution between internal and external channels as well as fuel and cladding temperature profiles is calculated with and without the fuel gap between the inner and outer pellets

Impact of emerging clean vehicle system on water stress

International Nuclear Information System (INIS)

Cai, Hua; Hu, Xiaojun; Xu, Ming

2013-01-01

Graphical abstract: Display Omitted - Highlights: • Clean vehicles may increase US water consumption up to 2810 billion gallons/year. • Large-scale clean vehicle adoption could lead to severe regional water stress. • Fuel choice for clean vehicle is crucial in minimizing regional water stress. • Regional optimization illustrated the importance of regional consideration. - Abstract: While clean vehicles (i.e., vehicles powered by alternative fuels other than fossil fuels) offer great potential to reduce greenhouse gas emissions from gasoline-based vehicles, the associated impact on water resources has not yet been fully assessed. This research provides a systematic evaluation of the impact of a fully implemented clean vehicle system on national and state-level water demand and water stress. On the national level, based on existing policies, transitioning the current gasoline-based transportation into one with clean vehicles will increase national annual water consumption by 1950–2810 billion gallons of water, depending on the market penetration of electric vehicles. On the state level, variances of water efficiency in producing different fuels are significant. The fuel choice for clean vehicle development is especially crucial for minimizing water stress increase in states with already high water stress, high travel demands, and significant variations in water efficiency in producing different alternative fuels. Current development of clean vehicle infrastructure, however, has not reflected these state-level variations. This study takes an optimization approach to further evaluate impacts on state-level water stress from a fully implemented clean vehicle system and identified potential roles (fuel producer or consumer) states may play in real world clean vehicle development scenario. With an objective of minimizing overall water stress impact, our optimization model aims to provide an analytical framework to better assess impacts on state-level water

Fuel system for diesel engine with multi-stage heated

Science.gov (United States)

Ryzhov, Yu N.; Kuznetsov, Yu A.; Kolomeichenko, A. V.; Kuznetsov, I. S.; Solovyev, R. Yu; Sharifullin, S. N.

2017-09-01

The article describes a fuel system of a diesel engine with a construction tractor multistage heating, allowing the use of pure rapeseed oil as a diesel engine fuel. The paper identified the kinematic viscosity depending on the temperature and composition of the mixed fuel, supplemented by the existing recommendations on the use of mixed fuels based on vegetable oils and developed the device allowing use as fuel for diesel engines of biofuels based on vegetable oils.

Castor-1C spent fuel storage cask decay heat, heat transfer, and shielding analyses

International Nuclear Information System (INIS)

Rector, D.R.; McCann, R.A.; Jenquin, U.P.; Heeb, C.M.; Creer, J.M.; Wheeler, C.L.

1986-12-01

This report documents the decay heat, heat transfer, and shielding analyses of the Gesellschaft fuer Nuklear Services (GNS) CASTOR-1C cask used in a spent fuel storage demonstration performed at Preussen Elektra's Wurgassen nuclear power plant. The demonstration was performed between March 1982 and January 1984, and resulted in cask and fuel temperature data and cask exterior surface gamma-ray and neutron radiation dose rate measurements. The purpose of the analyses reported here was to evaluate decay heat, heat transfer, and shielding computer codes. The analyses consisted of (1) performing pre-look predictions (predictions performed before the analysts were provided the test data), (2) comparing ORIGEN2 (decay heat), COBRA-SFS and HYDRA (heat transfer), and QAD and DOT (shielding) results to data, and (3) performing post-test analyses if appropriate. Even though two heat transfer codes were used to predict CASTOR-1C cask test data, no attempt was made to compare the two codes. The codes are being evaluated with other test data (single-assembly data and other cask data), and to compare the codes based on one set of data may be premature and lead to erroneous conclusions

Experimental analysis of indoor air quality improvement achieved by using a Clean-Air Heat Pump (CAHP) air-cleaner in a ventilation system

DEFF Research Database (Denmark)

Sheng, Ying; Fang, Lei; Nie, Jinzhe

2017-01-01

This study investigated the air purification effect of a Clean-Air Heat Pump (CAHP) air-cleaner which combined a silica gel rotor with a heat pump to achieve air cleaning, heating and ventilation in buildings. The experiments were conducted in a field laboratory and compared a low outdoor air...... supply rate with CAHP air purification of recirculated air with three different outdoor air supply rates without recirculation or air cleaning. Sensory assessments of perceived air quality and chemical measurements of TVOC concentration were used to evaluate the air-cleaning performance of the CAHP....... The results of the experiment showed that the operation of the CAHP significantly improved the perceived air quality in a room polluted by both human bio-effluents and building materials. At the outdoor airflow rate of 2 L/s per person, the indoor air quality with CAHP was equivalent to what was achieved...

Local Measurement of Fuel Energy Deposition and Heat Transfer Environment During Fuel Lifetime Using Controlled Calorimetry

International Nuclear Information System (INIS)

Don W. Miller; Andrew Kauffmann; Eric Kreidler; Dongxu Li; Hanying Liu; Daniel Mills; Thomas D. Radcliff; Joseph Talnagi

2001-01-01

A comprehensive description of the accomplishments of the DOE grant titled, ''Local Measurement of Fuel Energy Deposition and Heat Transfer Environment During Fuel Lifetime using Controlled Calorimetry''

Coolant clean-up system in nuclear reactor

International Nuclear Information System (INIS)

Tsuburaya, Hirobumi; Akita, Minoru; Shiraishi, Tadashi; Kinoshita, Shoichiro; Okura, Minoru; Tsuji, Akio.

1987-01-01

Purpose: To ensure a sufficient urging pressure at the inlet of a coolant clean-up system pump in a nuclear reactor and eliminate radioactive contaminations to the pump. Constitution: Coolant clean-up system (CUW) pump in a nuclear reactor is disposed to the downstream of a filtration desalter and, for compensating the insufficiency of the urging pressure at the pump inlet, the reactor water intake port to the clean-up system is disposed to the downstream of the after-heat removing pump and the heat exchanger. By compensating the net positive suction head (NPSH) of the clean-up system from the residual heat removing system, the problems of insufficient NPSH for the CUW pump upon reactor shut-down can be dissolved and, accordingly, the reactor clean-up system can be arranged in the order of the heat exchanger, clean-up device and pump. Thus, the CUW pump acts on reactor water after cleaned-up in the clean-up device to reduce the radioactivity contamination to the pump. (Kawakami, Y.)

National Clean Fleets Partnership (Fact Sheet)

Energy Technology Data Exchange (ETDEWEB)

None, None

2014-01-01

Clean Cities' National Clean Fleets Partnership establishes strategic alliances with large fleets to help them explore and adopt alternative fuels and fuel economy measures to cut petroleum use. The initiative leverages the strength of nearly 100 Clean Cities coalitions, nearly 18,000 stakeholders, and more than 20 years of experience. It provides fleets with top-level support, technical assistance, robust tools and resources, and public acknowledgement to help meet and celebrate fleets' petroleum-use reductions.

National Alliance for Clean Energy Incubators New Mexico Clean Energy Incubator

Energy Technology Data Exchange (ETDEWEB)

Roberts, Suzanne S.

2004-12-15

The National Alliance for Clean Energy Incubators was established by the National Renewable Energy Laboratory (NREL) to develop an emerging network of business incubators for entrepreneurs specializing in clean energy enterprises. The Alliance provides a broad range of business services to entrepreneurs in specific geographic locales across the U.S. and in diverse clean energy technology areas such as fuel cells, alternative fuels, power generation, and renewables, to name a few. Technology Ventures Corporation (TVC) participates in the Alliance from its corporate offices in Albuquerque, NM, and from its sites in Northern and Southern New Mexico, California, and Nevada. TVC reports on the results of its attempts to accelerate the growth and success of clean energy and energy efficiency companies through its array of business support services. During the period from September 2002 through September 2004, TVC describes contributions to the Alliance including the development of 28 clients and facilitating capital raises exceeding $35M.

Optimizing the Heat Exchanger Network of a Steam Reforming System

DEFF Research Database (Denmark)

Nielsen, Mads Pagh; Korsgaard, Anders Risum; Kær, Søren Knudsen

2004-01-01

Proton Exchange Membrane (PEM) based combined heat and power production systems are highly integrated energy systems. They may include a hydrogen production system and fuel cell stacks along with post combustion units optionally coupled with gas turbines. The considered system is based on a natural...... stationary numerical system model was used and process integration techniques for optimizing the heat exchanger network for the reforming unit are proposed. Objective is to minimize the system cost. Keywords: Fuel cells; Steam Reforming; Heat Exchanger Network (HEN) Synthesis; MINLP....... gas steam reformer along with gas purification reactors to generate clean hydrogen suited for a PEM stack. The temperatures in the various reactors in the fuel processing system vary from around 1000°C to the stack temperature at 80°C. Furthermore, external heating must be supplied to the endothermic...

Recent TMX-U central cell heating and fueling experiments

International Nuclear Information System (INIS)

Hooper, E.B. Jr.; Barter, J.; Dimonte, G.; Falabella, S.; Molvik, A.W.; Pincosy, P.; Turner, W.C.

1986-01-01

Recent experiments have begun to test new methods of heating and fueling of the TMX-U central cell plasma. Heating is with ICRH and 2kV neutral beams. Fueling is by the 2kV beams and by gas puffing. The ICRH system used for fundamental-frequency slow-wave heating consists of two double half-turn antennas, with one on each side of the central cell midplane at mirror ratios of 1:3 and 1:5. Gas fueling is between these two antennas to ensure that recently ionized particles pass through an ICRH resonance before entering the thermal barrier and cells. In recent gas-fed experiments with 100 to 200kW power on each antenna, the end loss temperature was measured to increase from 30eV to above 150eV with perpendicular (cc) temperatures of >500eV. The TMX-U central cell has been equipped with 10 low energy neutral-beam injectors (LENI). These beams are designed to operate at 2kV (net) accel-voltage and deliver 17 atom amperes each to the TMX-U plasma. This low energy was selected to improve trapping (relative to higher energy) on the initial ICRH heated plasma (2X10/sup 12/ cm/sup -3/). At 2keV the beams are predicted to be capable of building up and fueling to 10/sup 13/ cm/sup -3/ density, with ion-ion scattering providing a warm, isotropic ion component in the central cell

Sensitivity Analysis of Depletion Parameters for Heat Load Evaluation of PWR Spent Fuel Storage Pool

International Nuclear Information System (INIS)

Kim, In Young; Lee, Un Chul

2011-01-01

As necessity of safety re-evaluation for spent fuel storage facility has emphasized after the Fukushima accident, accuracy improvement of heat load evaluation has become more important to acquire reliable thermal-hydraulic evaluation results. As groundwork, parametric and sensitivity analyses of various storage conditions for Kori Unit 4 spent fuel storage pool and spent fuel depletion parameters such as axial burnup effect, operation history, and specific heat are conducted using ORIGEN2 code. According to heat load evaluation and parametric sensitivity analyses, decay heat of last discharged fuel comprises maximum 80.42% of total heat load of storage facility and there is a negative correlation between effect of depletion parameters and cooling period. It is determined that specific heat is most influential parameter and operation history is secondly influential parameter. And decay heat of just discharged fuel is varied from 0.34 to 1.66 times of average value and decay heat of 1 year cooled fuel is varied from 0.55 to 1.37 times of average value in accordance with change of specific power. Namely depletion parameters can cause large variation in decay heat calculation of short-term cooled fuel. Therefore application of real operation data instead of user selection value is needed to improve evaluation accuracy. It is expected that these results could be used to improve accuracy of heat load assessment and evaluate uncertainty of calculated heat load.

Fossil fuel and biomass burning effect on climate - heating or cooling

Energy Technology Data Exchange (ETDEWEB)

Kaufman, Y.J.; Fraser, R.S.; Mahoney, R.L. (NASA/Goddard Space Flight Center, Greenbelt, MD (USA))

1991-06-01

Emission from burning of fossil fuels and biomass (associated with deforestation) generates a radiative forcing on the atmosphere and a possible climate change. Emitted trace gases heat the atmosphere through their greenhouse effect, while particulates formed from emitted SO{sub 2} cause cooling by increasing cloud albedos through alteration of droplet size distributions. This paper reviews the characteristics of the cooling effect and applies Twomey's theory to check whether the radiative balance favours heating or cooling for the cases of fossil fuel and biomass burning. It is also shown that although coal and oil emit 120 times as many CO{sub 2} molecules as SO{sub 2} molecules, each SO{sub 2} molecule is 50-1100 times more effective in cooling the atmosphere (through the effect of aerosol particles on cloud albedo) than a CO{sub 2} molecule is in heating it. Note that this ratio accounts for the large difference in the aerosol (3-10 days) and CO{sub 2} (7-100 years) lifetimes. It is concluded, that the cooling effect from coal and oil burning may presently range from 0.4 to 8 times the heating effect. Within this large uncertainty, it is presently more likely that fossil fuel burning causes cooling of the atmosphere rather than heating. Biomass burning associated with deforestation, on the other hand, is more likely to cause heating of the atmosphere than cooling since its aerosol cooling effect is only half that from fossil fuel burning and its heating effect is twice as large. Future increases in coal and oil burning, and the resultant increase in concentration of cloud condensation nuclei, may saturate the cooling effect, allowing the heating effect to dominate. For a doubling in the CO{sub 2} concentration due to fossil fuel burning, the cooling effect is expected to be 0.1 to 0.3 of the heating effect. 75 refs., 8 tabs.

Clean energy and the hydrogen economy.

Science.gov (United States)

Brandon, N P; Kurban, Z

2017-07-28

In recent years, new-found interest in the hydrogen economy from both industry and academia has helped to shed light on its potential. Hydrogen can enable an energy revolution by providing much needed flexibility in renewable energy systems. As a clean energy carrier, hydrogen offers a range of benefits for simultaneously decarbonizing the transport, residential, commercial and industrial sectors. Hydrogen is shown here to have synergies with other low-carbon alternatives, and can enable a more cost-effective transition to de-carbonized and cleaner energy systems. This paper presents the opportunities for the use of hydrogen in key sectors of the economy and identifies the benefits and challenges within the hydrogen supply chain for power-to-gas, power-to-power and gas-to-gas supply pathways. While industry players have already started the market introduction of hydrogen fuel cell systems, including fuel cell electric vehicles and micro-combined heat and power devices, the use of hydrogen at grid scale requires the challenges of clean hydrogen production, bulk storage and distribution to be resolved. Ultimately, greater government support, in partnership with industry and academia, is still needed to realize hydrogen's potential across all economic sectors.This article is part of the themed issue 'The challenges of hydrogen and metals'. © 2017 The Author(s).

Numerical study on heat transfer characteristics of liquid-fueled molten salt using OpenFOAM

International Nuclear Information System (INIS)

Jeong, Yeong Shin; Bang, In Cheol

2017-01-01

To pursue sustainability and safety enhancement of nuclear energy, molten salt reactor is regarded as a promising candidate among various types of gen-IV reactors. Besides, pyroprocessing, which treats molten salt containing fission products, should consider safety related to decay heat from fuel material. For design of molten salt-related nuclear system, it is required to consider both thermal-hydraulic characteristics and neutronic behaviors for demonstration. However, fundamental heat transfer study of molten salt in operation condition is not easy to be experimentally studied due to its large scale, high temperature condition as well as difficulties of treating fuel material. >From that reason, numerical study can have benefit to investigate behaviors of liquid-fueled molten salt in real condition. In this study, open source CFD package OpenFOAM was used to analyze liquid-fueled molten salt loop having internal heat source as a first step of research. Among various molten salts considered as a candidate of liquid fueled molten salt reactors, in this study, FLiBe was chosen as liquid salt. For simulating heat generation from fuel material within fluid flow, volumetric heat source was set for fluid domain and OpenFOAM solver was modified as fvOptions as customized. To investigate thermal-hydraulic behavior of molten salt, CFD model was developed and validated by comparing experimental results in terms of heat transfer and pressure drop. As preliminary stage, 2D cavity simulations were performed to validate the modeling capacity of modified solver of OpenFOAM by comparison with those of ANSYS-CFX. In addition, cases of external heat flux and internal heat source were compared to configure the effect of heat source setting in various operation condition. As a result, modified solver of OpenFOAM considering internal heat source have sufficient modeling capacity to simulate liquid-fueled molten salt systems including heat generation cases. (author)

Clean Coal Diesel Demonstration Project

Energy Technology Data Exchange (ETDEWEB)

Robert Wilson

2006-10-31

A Clean Coal Diesel project was undertaken to demonstrate a new Clean Coal Technology that offers technical, economic and environmental advantages over conventional power generating methods. This innovative technology (developed to the prototype stage in an earlier DOE project completed in 1992) enables utilization of pre-processed clean coal fuel in large-bore, medium-speed, diesel engines. The diesel engines are conventional modern engines in many respects, except they are specially fitted with hardened parts to be compatible with the traces of abrasive ash in the coal-slurry fuel. Industrial and Municipal power generating applications in the 10 to 100 megawatt size range are the target applications. There are hundreds of such reciprocating engine power-plants operating throughout the world today on natural gas and/or heavy fuel oil.

Analysis of Fuel Cell Driven Ground Source Heat Pump Systems in Community Buildings

Directory of Open Access Journals (Sweden)

Jong-Keun Shin

2013-05-01

Full Text Available In the present study, a fuel cell driven ground source heat pump (GSHP system is applied in a community building and heat pump system performance is analyzed by computational methods. Conduction heat transfer between the brine pipe and ground is analyzed by TEACH code in order to predict the performance of the heat pump system. The predicted coefficient of performance (COP of the heat pump system and the energy cost were compared with the variation of the location of the objective building, the water saturation rate of the soil, and the driven powers of the heat pump system. Compared to the late-night electricity driven system, a significant reduction of energy cost can be accomplished by employing the fuel cell driven heat pump system. This is due to the low cost of electricity production of the fuel cell system and to the application of the recovered waste heat generated during the electricity production process to the heating of the community building.

Clean Cities Now Vol. 19, No. 2

Energy Technology Data Exchange (ETDEWEB)

None

2015-12-18

Clean Cities Now is the official bi-annual newsletter of Clean Cities, an initiative designed to reduce petroleum consumption in the transportation sector by advancing the use of alternative and renewable fuels, fuel economy improvements, idle-reduction measures, and new technologies, as they emerge.

Clean Cities Now Vol. 20, No. 2

Energy Technology Data Exchange (ETDEWEB)

None

2017-01-13

Clean Cities Now is the official semi-annual newsletter of Clean Cities, an initiative designed to reduce petroleum consumption in the transportation sector by advancing the use of alternative and renewable fuels, fuel economy improvements, idle-reduction measures, and new technologies, as they emerge.

Clean Cities Now Vol. 20, No. 1

Energy Technology Data Exchange (ETDEWEB)

None

2016-06-13

Clean Cities Now is the official semi-annual newsletter of Clean Cities, an initiative designed to reduce petroleum consumption in the transportation sector by advancing the use of alternative and renewable fuels, fuel economy improvements, idle-reduction measures, and new technologies, as they emerge.

Pool water cleaning facility

Energy Technology Data Exchange (ETDEWEB)

Yoshikawa, Kazuhiro; Kinoshita, Shoichiro [Hitachi Ltd., Tokyo (Japan); Asano, Takashi

1998-05-29

Only one system comprising a suppression poor water cleaning system (SPCU) and a filtration desalting tower (F/D) is connected for a plurality of nuclear power plants. Pipelines/valves for connecting the one system of the SPCU pump, the F/D and the plurality of nuclear power plants are disposed, and the system is used in common with the plurality of nuclear power plants. Pipelines/valves for connecting a pipeline for passing SP water to the commonly used SPCU pump and a skimmer surge tank are disposed, and fuel pool water is cooled and cleaned by the commonly used SPCU pump and the commonly used F/D. The number of SPCU pumps and the F/D facilities can be reduced, and a fuel pool water cooling operation mode and a fuel pool water cleaning operation mode which were conducted by an FPC pump so far are conducted by the SPCU pump. (N.H.)

Measurements of decay heat and gamma-ray intensity of spent LWR fuel assemblies

International Nuclear Information System (INIS)

Vogt, J.; Agrenius, L.; Jansson, P.; Baecklin, A.; Haakansson, A.; Jacobsson, S.

1999-01-01

Calorimetric measurements of the decay heat of a number of BWR and PWR fuel assemblies have been performed in the pools at the Swedish Central Interim Storage Facility for Spent Nuclear Fuel, CLAB. Gamma-ray measurements, using high-resolution gamma-ray spectroscopy (HRGS), have been carried out on the same fuel assemblies in order to test if it is possible to find a simple and accurate correlation between the 137 CS -intensity and the decay heat for fuel with a cooling time longer than 10-12 years. The results up to now are very promising and may ultimately lead to a qualified method for quick and accurate determination of the decay heat of old fuel by gamma-ray measurements. By means of the gamma spectrum the operator declared data on burnup, cooling time and initial enrichment can be verified as well. CLAB provides a unique opportunity in the world to follow up the decay heat of individual fuel assemblies during several decades to come. The results will be applicable for design and operation of facilities for wet and dry interim storage and subsequent encapsulation for final disposal of the fuel. (author)

Modelling of the spent fuel heat-up in the spent fuel pools using one-dimensional system codes and CFD codes

Energy Technology Data Exchange (ETDEWEB)

Grazevicius, Audrius; Kaliatka, Algirdas [Lithuanian Energy Institute, Kaunas (Lithuania). Lab. of Nuclear Installation Safety

2017-07-15

The main functions of spent fuel pools are to remove the residual heat from spent fuel assemblies and to perform the function of biological shielding. In the case of loss of heat removal from spent fuel pool, the fuel rods and pool water temperatures would increase continuously. After the saturated temperature is reached, due to evaporation of water the pool water level would drop, eventually causing the uncover of spent fuel assemblies, fuel overheating and fuel rods failure. This paper presents an analysis of loss of heat removal accident in spent fuel pool of BWR 4 and a comparison of two different modelling approaches. The one-dimensional system thermal-hydraulic computer code RELAP5 and CFD tool ANSYS Fluent were used for the analysis. The results are similar, but the local effects cannot be simulated using a one-dimensional code. The ANSYS Fluent calculation demonstrated that this three-dimensional treatment allows to avoid the need for many one-dimensional modelling assumptions in the pool modelling and enables to reduce the uncertainties associated with natural circulation flow calculation.

Engineering development of advance physical fine coal cleaning for premium fuel applications

Energy Technology Data Exchange (ETDEWEB)

Jha, M.C.; Smit, F.J.; Shields, G.L. [AMAX R& D Center/ENTECH Global Inc., Golden, CO (United States)

1995-11-01

The objective of this project is to develop the engineering design base for prototype fine coal cleaning plants based on Advanced Column Flotation and Selective Agglomeration processes for premium fuel and near-term applications. Removal of toxic trace elements is also being investigated. The scope of the project includes laboratory research and bench-scale testing of each process on six coals followed by design, construction, and operation of a 2 tons/hour process development unit (PDU). Three coals will be cleaned in tonnage quantity and provided to DOE and its contractors for combustion evaluation. Amax R&D (now a subsidiary of Cyprus Amax Mineral Company) is the prime contractor. Entech Global is managing the project and performing most of the research and development work as an on-site subcontractor. Other participants in the project are Cyprus Amax Coal Company, Arcanum, Bechtel, TIC, University of Kentucky and Virginia Tech. Drs. Keller of Syracuse and Dooher of Adelphi University are consultants.

Role of wall heat transfer and other system variables on fuel compaction and recriticality

International Nuclear Information System (INIS)

Dhir, V.K.; Castle, J.N.; Catton, I.; Kastenberg, W.E.; Doshi, J.B.

1976-01-01

The assessment of the molten fuel gaining recriticality after a hypothetical core disruptive accident in a fast reactor is an important safety consideration. Recriticality of the disrupted core can be envisioned to occur, if the fuel rearranges itself into a denser configuration either due to gravity slumping of the molten fuel or due to pressure or heat transfer driven compaction of the earlier dispersed fuel. In this paper the role played by wall heat transfer, internal radiation and the bottle pressure on the physical state of the molten fuel pool is discussed. It is suggested that in the absence of a solid crust the heat transfer process from the molten fuel to the surrounding steel will be very efficient because of melting and buoyancy driven removal of less dense steel through the pool of heavier UO 2 . The internal radiation at the high fuel temperature significantly increase the effective thermal conductivity of the molten fuel and lead to increased heat transfer in situations where a solid crust of UO 2 exists between molten UO 2 and molten steel. IN a boiled-up bottled pool, the pool pressure is shown to increase very rapidly with time and thus necessitate higher fission heating of the fuel to maintain it in a certain boiled up state. Finally, the results of the above discussion are applied to study the recriticality of a fuel pool formed during a hypothetical core disrupted accident in a fast reactor

Apparatus to simulate nuclear heating in advanced fuels

International Nuclear Information System (INIS)

Wrona, B.J.; Galvin, T.M.; Johanson, E.

1976-10-01

A direct-electrical-heating apparatus has been built to simulate in-reactor temperature gradients and heating conditions in both the mixed nitrides and carbides of uranium and plutonium. The apparatus has the capability for the investigation and direct observation of fuel-behavior phenomena that should significantly enlarge the data base on mixed carbides and nitrides at temperatures near and above their melting points. In addition to heating UC, results of prooftests showed that the apparatus has the capability to heat graphite, 30 vol % ZrC in graphite, B 4 C control-rod pellets, and stainless steel

Industrial space heating and cooling from stored spent nuclear power plant fuel

International Nuclear Information System (INIS)

Shaver, B.O.; Doman, J.W.

1980-01-01

Projections by the Department of Energy indicate that some 5800 metric tons of spent fuel from nuclear power reactors are now in storage and that some 33000 metric tons are expected to be in storage in 1990. The bulk of the spent fuel is currently stored in water-filled basins at the reactor sites from which the material was discharged. The thermal energy in the fuel is dissipated to atmospheres via a pumped water-to-air heat exchanger system. This paper describes a feasibility study of potential methods for the use of the heat. Also, potential applications of heat recovery systems at larger AFR storage facilities were investigated

Non-Fourier Vernotte-Cattaneo numerical model for heat conduction in a BWR fuel rod

Energy Technology Data Exchange (ETDEWEB)

Espinosa-Martinez, E.G.; Vazquez-Rodriguez, A.; Varela-Ham, J.R.; Espinosa-Paredes, G., E-mail: gepe@xanum.uam.mx [Universidad Autonoma Metropolitana, Area de Ingenieria en Recursos Energeticos, Iztapalapa (Mexico)

2014-07-01

A fuel rod mathematical model based on transient heat conduction as constitutive Non-Fourier law for Light Water Reactors (LWRs) transient analysis is presented. The structure of the fuel pellet is affected due to high temperatures and irradiation, which eventually produce fracture or cracks. In principle the fractures are saturated of gas. Then, the Fourier law of the heat conduction is not strictly applicable to describe these phenomena, where the physical properties such as thermal conductivity, heat capacity and density correspond to a heterogeneous material due to gas, and therefore the thermal diffusion process due to molecular transport in the fuel pellet is affected. From the point of view of nuclear reactor safety analysis, the heat transfer from the fuel to the coolant is crucial and superheating of the wall can cause the cladding failure. In the classical theory of diffusion, the Fourier law of heat conduction is used to describe the relation between the heat flux vector and the temperature gradient assuming that the heat propagation speeds are infinite. The Non-Fourier approach presented in this work eliminates the assumption of an infinite thermal wave speed, therefore time-dependent heat sources were considered in the fuel rod heat transfer model. The numerical experiments in a BWR, show that the Non-Fourier approach is crucial in the pressurization transients such as turbine trip and reactor isolation. (author)

Non-Fourier Vernotte-Cattaneo numerical model for heat conduction in a BWR fuel rod

International Nuclear Information System (INIS)

Espinosa-Martinez, E.G.; Vazquez-Rodriguez, A.; Varela-Ham, J.R.; Espinosa-Paredes, G.

2014-01-01

A fuel rod mathematical model based on transient heat conduction as constitutive Non-Fourier law for Light Water Reactors (LWRs) transient analysis is presented. The structure of the fuel pellet is affected due to high temperatures and irradiation, which eventually produce fracture or cracks. In principle the fractures are saturated of gas. Then, the Fourier law of the heat conduction is not strictly applicable to describe these phenomena, where the physical properties such as thermal conductivity, heat capacity and density correspond to a heterogeneous material due to gas, and therefore the thermal diffusion process due to molecular transport in the fuel pellet is affected. From the point of view of nuclear reactor safety analysis, the heat transfer from the fuel to the coolant is crucial and superheating of the wall can cause the cladding failure. In the classical theory of diffusion, the Fourier law of heat conduction is used to describe the relation between the heat flux vector and the temperature gradient assuming that the heat propagation speeds are infinite. The Non-Fourier approach presented in this work eliminates the assumption of an infinite thermal wave speed, therefore time-dependent heat sources were considered in the fuel rod heat transfer model. The numerical experiments in a BWR, show that the Non-Fourier approach is crucial in the pressurization transients such as turbine trip and reactor isolation. (author)

Removal of sulphur-containing odorants from fuel gases for fuel cell-based combined heat and power applications

NARCIS (Netherlands)

Wild, de P.J.; Nyqvist, R.G.; Bruijn, de F.A.; Stobbe, E.R.

2006-01-01

Natural gas (NG) and liquefied petroleum gas (LPG) are important potential feedstocks for the production of hydrogen for fuel cell-based(e.g. proton exchange membrane fuel cells (PEMFC) or solid oxide fuel Cells (SOFC) combined heat and power (CHP) applications. To preventdetrimental effects on the

Trapped in the heat: A post-communist type of fuel poverty

International Nuclear Information System (INIS)

Tirado Herrero, Sergio; Ürge-Vorsatz, Diana

2012-01-01

Fuel poverty is a still insufficiently researched social and energy challenge with significant climate change implications. Based on evidence from Hungarian panel apartment blocks connected to district heating, this paper introduces a new variant of fuel poverty that may not be properly captured by existing fuel poverty indicators. This newly defined variant can be largely attributed to post-communist legacies – though it might also exist in other contexts – and assumes that consumers living in poor-efficiency, district-heated buildings are trapped in dwellings with adequate indoor temperatures but disproportionately high heating costs because (a) changing supplier or fuel is difficult because of the existing technical and institutional constraints, and (b) they do not realistically have the option to reduce individually their heating costs through individual efficiency improvements. This situation often translates into payment arrears, indebtedness, risk of disconnection, or reduced consumption of other basic goods and services. State-supported policy responses to date have favoured symptomatic solutions (direct consumer support) combined with superficial retrofits, though it is argued that only state-of-the-art retrofits such as the passive house-based SOLANOVA pilot project in Dunaújváros can fully eradicate fuel poverty in this consumer group. - Highlights: ► We identify a new variant of fuel poverty. ► We explore this variant in panel apartment blocks connected to DH in Hungary, where dwellings are warm enough in winter but have disproportionately high energy costs. ► Affected households react in ways that harm their welfare and put them at risk. ► Deep retrofits in dwellings such as these can eradicate fuel poverty while also contributing to other goals.

Substitution of chlorinated and fluorinated solvents by biodegradable detergent solution in components cleaning of nuclear fuel elements

International Nuclear Information System (INIS)

Vieira, Andre Luiz Pinto da Silva

2000-01-01

As the auxiliary oils used in machining evolved from integral into aqueous emulsion, and later on into aqueous-solution synthetic oils, the components cleaning process with organic solvents, originally adopted at the Fuel Element Factory (FEC), Industrias Nucleares do Brasil S.A. (INB) began to present problems in removing oil residues from machined components, due to the incompatibility between aqueous and organic media. In order to eliminate such incompatibility and adapt the process to the environmental laws restricting production and use of chlorinated or fluorinated solvents as a measure for preserving the atmosphere's ozone layer, in 1995 INB initiated the development of a components cleaning process using biodegradable aqueous detergent. The effort was completed in 2000 with the construction of a machine in keeping with the specific geometry of the fuel-assembly components and the operating conditions required for working with the new process. (author)

ComfortPower. Design, construction and evaluation of a combined fuel-cell and heat pump system

Energy Technology Data Exchange (ETDEWEB)

Silversand, Fredrik (Catator AB, Lund (Sweden))

2010-12-15

Catator AB has constructed, commissioned and evaluated a combined fuel-cell and heat-pump system (ComfortPower). The basic idea behind the project was to demonstrate the possibility to achieve ultrahigh thermal efficiencies when combining fuel-cell technologies and heat pumps. Moreover, the system should provide a great flexibility with respect to the fuel mix and should in addition to heat provide surplus electricity and cooling. The system was built on a HT-PEM platform (high temperature polymer electrolyte fuel cell from Serenergy a/s), which was operated by Catators proprietary Optiformer technology. The power generator was combined with a heat pump module (F1145-5, 230 V), supplied by Nibe. The system was packaged into a cabinet (1.65 x 0.6 x 0.6 m) comprising the power module, the heat pump, all necessary balance-of-plant components and the control system. The power output from the fuel-cell system was around 1.35 kW, which enabled operation of the heat pump compressor. By utilizing surplus heat energy from the fuel cell it was possible to achieve a favourable operation point in the heat pump system, resulting in a high overall COP (coefficient of performance). The heat output from the system was as high as 10 kW whereas 6 kW cooling could be provided. The thermal efficiencies measured in experiments were normally around 200%, calculated on the lower heating value of the fuel. A number of fuels have been investigated in the fuel cell system, including both gaseous (natural gas/LPG) and liquid fuels (alcohols and kerosene). Indeed, the system has a wide fuel flexibility, which opens up for a variety of applications in campus villages and buildings. This study has demonstrated the possibility to reduce the carbon dioxide footprint by a factor of 2 over conventional boilers in heating applications. In addition the unit can be operated on a variety of fuels and can produce cooling and electricity in addition to heat. A fully working system has been designed

Fossil fuels and air pollution in USA after the Clean Air Act

International Nuclear Information System (INIS)

Chuveliov, A.V.

1990-01-01

This paper addresses environmental issues in the USA after the Clean Air Act. Economic damage assessment to population and environment due to air pollution from stationary and mobile sources producing and utilizing fossil fuels in the USA for the period of 1970--1986 is determined and discussed. A comparison of environmental damage assessments for the USA and USSR is provided. The paper also addresses ecologo-economical aspects of hydrogen energy and technology. The effectiveness of hydrogen use in ferrous metallurgy and motor vehicles in the USA is determined and discussed

A study on gap heat transfer of LWR fuel rods under reactivity initiated accident conditions

International Nuclear Information System (INIS)

Fujishiro, Toshio

1984-03-01

Gap heat transfer between fuel pellet and cladding have a large influence on the LWR fuel behaviors under reactivity initiated accident (RIA) conditions. The objective of the present study is to investigate the effects of gap heat transfer on RIA fuel behaviors based on the results of the gap-gas parameter tests in NSRR and on their analysis with NSR-77 code. Through this study, transient variations of gap heat transfer, the effects of the gap heat transfer on fuel thermal behaviors and on fuel failure, effects of pellet-cladding sticking by eutectic formation, and the effects of cladding collapse under high external pressure have been clearified. The studies have also been performed on the applicability and its limit of modified Ross and Stoute equation which is extensively utilized to evaluate the gap heat transfer coefficient in the present fuel behavior codes. The method to evaluate the gap conductance to the conditions beyond the applicability limit of the Ross and Stoute equation has also been proposed. (author)

Fuel flexible distributed combustion for efficient and clean gas turbine engines

International Nuclear Information System (INIS)

Khalil, Ahmed E.E.; Gupta, Ashwani K.

2013-01-01

Highlights: • Examined distributed combustion for gas turbines applications using HiTAC. • Gaseous, liquid, conventional and bio-fuels are examined with ultra-low emissions. • Novel design of fuel flexibility without any atomizer for liquid fuel sprays. • Demonstrated fuel flexibility with emissions x and CO, low noise, enhanced stability, higher efficiency and alleviation of combustion instability. Distributed reaction conditions were achieved using swirl for desirable controlled mixing between the injected air, fuel and hot reactive gases from within the combustor prior to mixture ignition. In this paper, distributed combustion is further investigated using a variety of fuels. Gaseous (methane, diluted methane, hydrogen enriched methane and propane) and liquid fuels, including both traditional (kerosene) and alternate fuels (ethanol) that cover a wide range of calorific values are investigated with emphasis on pollutants emission and combustor performance with each fuel. For liquid fuels, no atomization or spray device was used. Performance evaluation with the different fuels was established to outline the flexibility of the combustor using a wide range of fuels of different composition, phase and calorific value with specific focus on ultra-low pollutants emission. Results obtained on pollutants emission and OH * chemiluminescence for the specific fuels at various equivalence ratios are presented. Near distributed combustion conditions with less than 8 PPM of NO emission were demonstrated under novel premixed conditions for the various fuels tested at heat (energy) release intensity (HRI) of 27 MW/m 3 -atm. and a rather high equivalence ratio of 0.6. Higher equivalence ratios lacked favorable distributed combustion conditions. For the same conditions, CO emission varied for each fuel; less than 10 ppm were demonstrated for methane based fuels, while heavier liquid fuels provided less than 40 ppm CO emissions. Lower emissions of NO ( x can be possible by

Adoption of Clean Cookstoves after Improved Solid Fuel Stove Programme Exposure: A Cross-Sectional Study in Three Peruvian Andean Regions.

Science.gov (United States)

Wolf, Jennyfer; Mäusezahl, Daniel; Verastegui, Hector; Hartinger, Stella M

2017-07-08

This study examined measures of clean cookstove adoption after improved solid fuel stove programmes in three geographically and culturally diverse rural Andean settings and explored factors associated with these measures. A questionnaire was administered to 1200 households on stove use and cooking behaviours including previously defined factors associated with clean cookstove adoption. Logistic multivariable regressions with 16 pre-specified explanatory variables were performed for three outcomes; (1) daily improved solid fuel stove use, (2) use of liquefied petroleum gas stove and (3) traditional stove displacement. Eighty-seven percent of households reported daily improved solid fuel stove use, 51% liquefied petroleum gas stove use and 66% no longer used the traditional cookstove. Variables associated with one or more of the three outcomes are: education, age and civil status of the reporting female, household wealth and size, region, encounters of problems with the improved solid fuel stove, knowledge of somebody able to build an improved solid fuel stove, whether stove parts are obtainable in the community, and subsidy schemes. We conclude that to be successful, improved solid fuel stove programmes need to consider (1) existing household characteristics, (2) the household's need for ready access to maintenance and repair, and (3) improved knowledge at the community level.

An experimental evaluation on air purification performance of Clean-Air Heat Pump (CAHP) air cleaner

DEFF Research Database (Denmark)

Sheng, Ying; Fang, Lei; Sun, Yuexia

2018-01-01

was 96.8%, which indicated that the most of gaseous pollutants were not accumulated in the CAHP. The regeneration temperature for the wheel could affect the air purification performance of CAHP. At 70 °C of regeneration temperature, the air-cleaning efficiency reached 96.7%. Up to 70% of the outdoor air......The escalation of energy consumption in buildings and heightened concerns about acceptable indoor air quality stimulate interest in the usage of air cleaner as an adjunct for indoor environmental conditioning. A regenerative desiccant wheel integrated into a ventilation system termed Clean-Air Heat...... Pump (CAHP) can improve the air quality during the process of dehumidification without using additional energy. An experimental study in a field lab was performed to investigate the air cleaning performance of CAHP. Photoacoustic gas analyzer-INNOVA was used to characterize chemical removal of indoor...

Micro-tubular flame-assisted fuel cells for micro-combined heat and power systems

Science.gov (United States)

Milcarek, Ryan J.; Wang, Kang; Falkenstein-Smith, Ryan L.; Ahn, Jeongmin

2016-02-01

Currently the role of fuel cells in future power generation is being examined, tested and discussed. However, implementing systems is more difficult because of sealing challenges, slow start-up and complex thermal management and fuel processing. A novel furnace system with a flame-assisted fuel cell is proposed that combines the thermal management and fuel processing systems by utilizing fuel-rich combustion. In addition, the flame-assisted fuel cell furnace is a micro-combined heat and power system, which can produce electricity for homes or businesses, providing resilience during power disruption while still providing heat. A micro-tubular solid oxide fuel cell achieves a significant performance of 430 mW cm-2 operating in a model fuel-rich exhaust stream.

Techno-economic analysis of a local district heating plant under fuel flexibility and performance

DEFF Research Database (Denmark)

Rudra, Souman; Rosendahl, Lasse

2017-01-01

are calculated using the same procedure according to the use of various local renewable fuels known as “biogas option,” “solar option,” “heat pump option,” and “imported heat option.” A comparison has been made between the reference option and other options. The greatest reduction in heat cost is obtained from......, an investigation has been made to reduce the use of fossil fuels for district heating system and make use of the local renewable resources (biogas, solar, and heat pump) for district heating purposes. In this article, the techno-economic assessment is achieved through the development of a suite of models...... the biogas option by replacing a new engine, where 66 % of the current fuel is substituted with biogas....

Wood fuel from early thinning and plantation cleaning. Summary of an international review

International Nuclear Information System (INIS)

Puttock, D.

1998-01-01

This paper summaries the results of an international of wood fuel from early thinning and plantation cleaning. The economic and biological benefits from early thinning have been well documented. However, removing forest biomass during early stages of stand development from sites which are low in one or more nutrients may contribute a loss of nutrients and organic matter. Depending on the pre-thinning density and the thinning intensity, the potential yield of wood fuel from early thinning may be as much as 79 dry tons per hectare. Thus, wood fuel from the thinnings could be an important source of revenue to forest owners and would contribute to domestic energy requirements. Motor-manual felling predominates in early thinning, mainly due to the lack of appropriate technology for thinning small trees. However, the productivity of motor-manual felling is greatly affected by the initial stand density and declines dramatically at densities greater than 10 000 stems per ha. Under these conditions, purpose-built wood fuel harvesters with small-tree harvesting capability offer the greatest potential for increasing felling productivity and reducing the cost of wood fuel. The cost of wood fuel from early thinnings varies widely between countries from USD 25.00 - 87.50 per dry ton depending on stand conditions, harvesting system, transport distance, domestic tax rates, and stumpage prices. At the low end of this range, wood fuel chips from early thinning are competitive with wood fuel produced from mill waste, the residues from clearfell operations, or from later thinnings

Application of fuel cells with heat recovery for integrated utility systems

Science.gov (United States)

Shields, V.; King, J. M., Jr.

1975-01-01

This paper presents the results of a study of fuel cell powerplants with heat recovery for use in an integrated utility system. Such a design provides for a low pollution, noise-free, highly efficient integrated utility. Use of the waste heat from the fuel cell powerplant in an integrated utility system for the village center complex of a new community results in a reduction in resource consumption of 42 percent compared to conventional methods. In addition, the system has the potential of operating on fuels produced from waste materials (pyrolysis and digester gases); this would provide further reduction in energy consumption.

Ultra Low Sulfur Home Heating Oil Demonstration Project

Energy Technology Data Exchange (ETDEWEB)

Batey, John E. [Energy Research Center, Inc., Easton, CT (United States); McDonald, Roger [Brookhaven National Lab. (BNL), Upton, NY (United States)

2015-09-30

This Ultra Low Sulfur (ULS) Home Heating Oil Demonstration Project was funded by the New York State Energy Research and Development Authority (NYSERDA) and has successfully quantified the environmental and economic benefits of switching to ULS (15 PPM sulfur) heating oil. It advances a prior field study of Low Sulfur (500 ppm sulfur) heating oil funded by NYSERDA and laboratory research conducted by Brookhaven National Laboratory (BNL) and Canadian researchers. The sulfur oxide and particulate matter (PM) emissions are greatly reduced as are boiler cleaning costs through extending cleaning intervals. Both the sulfur oxide and PM emission rates are directly related to the fuel oil sulfur content. The sulfur oxide and PM emission rates approach near-zero levels by switching heating equipment to ULS fuel oil, and these emissions become comparable to heating equipment fired by natural gas. This demonstration project included an in-depth review and analysis of service records for both the ULS and control groups to determine any difference in the service needs for the two groups. The detailed service records for both groups were collected and analyzed and the results were entered into two spreadsheets that enabled a quantitative side-by-side comparison of equipment service for the entire duration of the ULS test project. The service frequency for the ULS and control group were very similar and did indicate increased service frequency for the ULS group. In fact, the service frequency with the ULS group was slightly less (7.5 percent) than the control group. The only exception was that three burner fuel pump required replacement for the ULS group and none were required for the control group.

The thermal performance of a loop-type heat pipe for passively removing residual heat from spent fuel pool

Energy Technology Data Exchange (ETDEWEB)

Xiong, Zhenqin [School of Nuclear Science and Engineering, Shanghai Jiao Tong University, No. 800 Dongchuan Road, Shanghai 200240 (China); Gu, Hanyang, E-mail: guhanyang@stu.edu.cn [School of Nuclear Science and Engineering, Shanghai Jiao Tong University, No. 800 Dongchuan Road, Shanghai 200240 (China); Wang, Minglu [School of Nuclear Science and Engineering, Shanghai Jiao Tong University, No. 800 Dongchuan Road, Shanghai 200240 (China); Cheng, Ye [Shanghai Nuclear Engineering Research and Design Institute, Shanghai 200233 (China)

2014-12-15

Highlights: • Feasibility of applying loop-type heat pipes for SFP is studied. • The heat transfer rate of the heat pipes was tested. • The heat transfer coefficient was between 200 and 490 W/m{sup 2}/s. • The effect of the water temperature is dominant. • Three kinds of the filling ratio 27%, 21% and 14% are compared. - Abstract: Heat pipe is an efficient heat transfer device without electrically driven parts. Therefore large-scale loop type heat pipe systems have potential uses for passively removing heat from spent fuel pools and reactor cores under the accidental conditions to improve the safety of the nuclear power station. However, temperature difference between the hot water in the spent fuel pool and the ambient air which is the heat sink is small, in the range of 20–60 °C. To understand and predict the heat removal capacity of such a large scale loop type heat pipe in the situation similar to the accidental condition of the spent fuel pool (SFP) for the design purpose, a loop-type heat pipe with a very high and large evaporator has been fabricated and was tested using ammonia as the working fluid. The evaporator with inner diameter of 65 mm and length of 7.6 m is immersed in a hot water tube which simulate the spent fuel pool. The condenser of the loop-type heat pipe is cooled by the air. The tests were performed with the velocity of the hot water in the tube in the range of 0.7–2.1 × 10{sup −2} m/s, the hot water inlet temperature between 50 and 90 °C and the air velocity ranging from 0.5 m/s to 2.5 m/s. Three kinds of the ammonia volumetric filling ratio in the heat pipe were tested, i.e. 27%, 21% and 14%. It is found that the heat transfer rate was in the range of 1.5–14.9 kW, and the heat transfer coefficient of evaporator was between 200 and 490 W/m{sup 2}/s. It is feasible to use the large scale loop type heat pipe to passively remove the residual heat from SFP. Furthermore, the effect of air velocity, air temperature, water flow

The thermal performance of a loop-type heat pipe for passively removing residual heat from spent fuel pool

International Nuclear Information System (INIS)

Xiong, Zhenqin; Gu, Hanyang; Wang, Minglu; Cheng, Ye

2014-01-01

Highlights: • Feasibility of applying loop-type heat pipes for SFP is studied. • The heat transfer rate of the heat pipes was tested. • The heat transfer coefficient was between 200 and 490 W/m 2 /s. • The effect of the water temperature is dominant. • Three kinds of the filling ratio 27%, 21% and 14% are compared. - Abstract: Heat pipe is an efficient heat transfer device without electrically driven parts. Therefore large-scale loop type heat pipe systems have potential uses for passively removing heat from spent fuel pools and reactor cores under the accidental conditions to improve the safety of the nuclear power station. However, temperature difference between the hot water in the spent fuel pool and the ambient air which is the heat sink is small, in the range of 20–60 °C. To understand and predict the heat removal capacity of such a large scale loop type heat pipe in the situation similar to the accidental condition of the spent fuel pool (SFP) for the design purpose, a loop-type heat pipe with a very high and large evaporator has been fabricated and was tested using ammonia as the working fluid. The evaporator with inner diameter of 65 mm and length of 7.6 m is immersed in a hot water tube which simulate the spent fuel pool. The condenser of the loop-type heat pipe is cooled by the air. The tests were performed with the velocity of the hot water in the tube in the range of 0.7–2.1 × 10 −2 m/s, the hot water inlet temperature between 50 and 90 °C and the air velocity ranging from 0.5 m/s to 2.5 m/s. Three kinds of the ammonia volumetric filling ratio in the heat pipe were tested, i.e. 27%, 21% and 14%. It is found that the heat transfer rate was in the range of 1.5–14.9 kW, and the heat transfer coefficient of evaporator was between 200 and 490 W/m 2 /s. It is feasible to use the large scale loop type heat pipe to passively remove the residual heat from SFP. Furthermore, the effect of air velocity, air temperature, water flow rate and

Heat evaluation examination of fuel assembly

International Nuclear Information System (INIS)

Suto, Shinya; Nakabayashi, Hiroki; Yao, Kaoru

2007-03-01

The cooling examination was executed by using the simulated fuel assembly to obtain the basic data of the most effective cooling system in the lazer disassembling process of the spent fuel assembly of prototype fast breeder reactor 'Monju'. As a result, the following have been understood. (1) Before the laser disassembling (there is not any duct tube cutting), it is possible to cool enough by the amount of the wind of 20m 3 /h or more flowing from the handling head side. (2) After the laser disassembling begins (duct tube is cut), 1kW or more of the heat generation cannot be cooled by ventilation from the handling head side. (3) Cooling by the flow across fuel pin is required during lazer disassembling. The basic data of the cooling system was obtained from these examination results. However, for cooling across fuel pin during the laser disassembling, it is necessary to examine shape of the side cooling nozzle, spraying angle, and flow velocity at the nozzle exit, etc. enough. (author)

Linking long-range weather forecasts and heat consumption as a determining factor when buying fuel chips for town heating plants

International Nuclear Information System (INIS)

Rolev, A.-M.

1991-12-01

The aim of this study is to test whether long-range weather forecasts from the meteorological services can be used as a determining factor when buying fuel chips. In the study the fuel consumption of heating plants and the factors determining the monthly consumption are mentioned. Degree-day statistics in Denmark for the last 30 years are explained as well as the difficulties in conjunction with the prediction of long-range weather conditions. This study compares degree days in 1989-1990 month by month with the actual and theoretic chip consumption in three different heating plants the same year. The theoretic chip consumption is calculated on the basis of degree days in a ''standard year'' and the annual chip consumption of the heating plant, among other things. Furthermore, on the basis of degree-day statistics the report makes it possible to estimate the monthly chip consumption of a heating plant in a ''standard year'', in an extremely cold year (maximum degree days), and in an extremely warm year (minimum degree days). However, not everything can be predicted, and it is not yet possible to predict reliable weather forecasts for more than 5 days ahead. The study concludes that long-range weather forecasts cannot be used as a determining factor when buying fuel chips for heating plants. When buying fuel chips one must still use statistics and degree days, supplimented by figures based on experience from actual chip consumption in the individual heating plant. These figures take into consideration the different types of heating plants, as well as heat supply, chip-supplier, storing facilities, other fuels, etc. (au)

Modeling and optimization of a heat-pump-assisted high temperature proton exchange membrane fuel cell micro-combined-heat-and-power system for residential applications

DEFF Research Database (Denmark)

Arsalis, Alexandros; Kær, Søren Knudsen; Nielsen, Mads Pagh

2015-01-01

In this study a micro-combined-heat-and-power (micro-CHP) system is coupled to a vapor-compression heat pump to fulfill the residential needs for heating (space heating and water heating) and electricity in detached single-family households in Denmark. Such a combination is assumed to be attractive...... for application, since both fuel cell technology and electric heat pumps are found to be two of the most efficient technologies for generation/conversion of useful energy. The micro-CHP system is fueled with natural gas and includes a fuel cell stack, a fuel processor and other auxiliary components. The micro......-CHP system assumes heat-led operation, to avoid dumping of heat and the use of complicated thermal energy storage. The overall system is grid-interconnected to allow importing and exporting of electricity as necessary. In this study emphasis is given on the operational characterization of the system...

Heat Transfer Coefficient Variations in Nuclear Fuel Rod Bundles

International Nuclear Information System (INIS)

Conner, Michael E.; Holloway, Mary V.

2007-01-01

The single-phase heat transfer performance of a PWR nuclear fuel rod bundle is enhanced by the use of mixing vanes attached to the downstream edges of the support grid straps. This improved single-phase performance will delay the onset of nucleate boiling, thereby reducing corrosion and delaying crud-related issues. This paper presents the variation in measured single-phase heat transfer coefficients (HTC) for several grid designs. Then, this variation is compared with observations of actual in-core crud patterns. While crud deposition is a function of a number of parameters including rod heat flux, the HTC is assumed to be a primary factor in explaining why crud deposition is a local phenomenon on nuclear fuel rods. The data from this study will be used to examine this assumption by providing a comparison between HTC variations and crud deposition patterns. (authors)

Clean Cities 2012 Annual Metrics Report

Energy Technology Data Exchange (ETDEWEB)

Johnson, Caley [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2013-12-01

The U.S. Department of Energy's (DOE) Clean Cities program advances the nation's economic, environmental, and energy security by supporting local actions to cut petroleum use in transportation. A national network of nearly 100 Clean Cities coalitions brings together stakeholders in the public and private sectors to deploy alternative and renewable fuels, idle-reduction measures, fuel economy improvements, and new transportation technologies, as they emerge. Each year DOE asks Clean Cities coordinators to submit annual reports of their activities and accomplishments for the previous calendar year. Data and information are submitted via an online database that is maintained as part of the Alternative Fuels Data Center (AFDC) at the National Renewable Energy Laboratory (NREL). Coordinators submit a range of data that characterizes the membership, funding, projects, and activities of their coalitions. They also submit data about sales of alternative fuels, deployment of alternative fuel vehicles (AFVs) and hybrid electric vehicles (HEVs), idle-reduction initiatives, fuel economy activities, and programs to reduce vehicle miles traveled (VMT). NREL analyzes the data and translates them into petroleum-use reduction impacts, which are summarized in this report.

Conversion of sewage sludge to clean solid fuel using hydrothermal carbonization: Hydrochar fuel characteristics and combustion behavior

International Nuclear Information System (INIS)

He, Chao; Giannis, Apostolos; Wang, Jing-Yuan

2013-01-01

Highlights: • The hydrothermal carbonization of sewage sludge process is developed. • Hydrochars are solid fuels with less nitrogen and sulfur contents. • The first order combustion reaction of hydrochars is derived. • Main combustion decomposition of hydrochars is easier and more stable. • Formation pathways of hydrochars during hydrothermal carbonization are proposed. - Abstract: Conventional thermochemical treatment of sewage sludge (SS) is energy-intensive due to its high moisture content. To overcome this drawback, the hydrothermal carbonization (HTC) process was used to convert SS into clean solid fuel without prior drying. Different carbonization times were applied in order to produce hydrochars possessing better fuel properties. After the carbonization process, fuel characteristics and combustion behaviors of hydrochars were evaluated. Elemental analysis showed that 88% of carbon was recovered while 60% of nitrogen and sulfur was removed. Due to dehydration and decarboxylation reactions, hydrogen/carbon and oxygen/carbon atomic ratios reduced to 1.53 and 0.39, respectively. It was found that the fuel ratio increased to 0.18 by prolonging the carbonization process. Besides, longer carbonization time seemed to decrease oxygen containing functional groups while carbon aromaticity structure increased, thereby rendering hydrochars highly hydrophobic. The thermogravimetric analysis showed that the combustion decomposition was altered from a single stage for raw sludge to two stages for hydrochars. The combustion reaction was best fitted to the first order for both raw sludge and hydrochars. The combustion of hydrochars is expected to be easier and more stable than raw sludge because of lower activation energy and pre-exponential factor

Optimization of a local district heating plant under fuel flexibility and performance

DEFF Research Database (Denmark)

Rudra, Souman; Rosendahl, Lasse; From, Niels

2011-01-01

are calculated for various local fuels in energyPRO. A comparison has been made between the reference model and the basis for individual solutions. The greatest reduction in heat price is obtained by replacing one engine with a new biogas where heat production is divided by 66% of biogas, 13% natural gas engines......, an investigation has been made to reduce the use of fossil fuels for district heating system and make use of the local renewable resources (Biogas, Solar and Geothermal) for district heating purpose. In this article, the techno-economic assessment is achieved through the development of a suite of models...

BWR spent fuel storage cask performance test. Volume 2. Pre- and post-test decay heat, heat transfer, and shielding analyses

International Nuclear Information System (INIS)

Wiles, L.E.; Lombardo, N.J.; Heeb, C.M.; Jenquin, U.P.; Michener, T.E.; Wheeler, C.L.; Creer, J.M.; McCann, R.A.

1986-06-01

This report describes the decay heat, heat transfer, and shielding analyses conducted in support of performance testing of a Ridhihalgh, Eggers and Associates REA 2033 boiling water reactor (BWR) spent fuel storage cask. The cask testing program was conducted for the US Department of Energy (DOE) Commercial Spent Fuel Management Program by the Pacific Northwest Laboratory (PNL) and by General Electric at the latters' Morris Operation (GE-MO) as reported in Volume I. The analyses effort consisted of performing pretest calculations to (1) select spent fuel for the test; (2) symmetrically load the spent fuel assemblies in the cask to ensure lateral symmetry of decay heat generation rates; (3) optimally locate temperature and dose rate instrumentation in the cask and spent fuel assemblies; and (4) evaluate the ORIGEN2 (decay heat), HYDRA and COBRA-SFS (heat transfer), and QAD and DOT (shielding) computer codes. The emphasis of this second volume is on the comparison of code predictions to experimental test data in support of the code evaluation process. Code evaluations were accomplished by comparing pretest (actually pre-look, since some predictions were not completed until testing was in progress) predictions with experimental cask testing data reported in Volume I. No attempt was made in this study to compare the two heat transfer codes because results of other evaluations have not been completed, and a comparison based on one data set may lead to erroneous conclusions

Overview of material migration and mixing, fuel retention and cleaning of ITER-like castellated structures in TEXTOR

International Nuclear Information System (INIS)

Litnovsky, A.; Philipps, V.; Wienhold, P.; Kreter, A.; Kirschner, A.; Matveev, D.; Brezinsek, S.; Sergienko, G.; Pospieszczyk, A.; Schweer, B.; Schulz, C.; Schmitz, O.; Coenen, J.W.; Samm, U.; Krieger, K.; Hirai, T.; Emmoth, B.; Rubel, M.; Bazylev, B.; Breuer, U.

2011-01-01

Plasma-facing components (PFCs) in ITER will be castellated by splitting them into small-size blocks to maintain the thermo-mechanical stability. However, there are concerns in particular on retention of codeposited radioactive fuel in the gaps. An R and D program is underway in TEXTOR addressing this acute issue of castellation. Material migration and fuel inventory are investigated using long- and short-term discharge-resolved experiments with castellated structures in TEXTOR. Significant impurity transport to the gaps was detected and results were in part quantitatively reproduced with 3D-GAPS code. Deposits containing up to 70 at.% of tungsten on the gap areas closest to the plasma were detected in recent experiments. Deposition in the gaps accompanied by metal mixing demand for development of effective cleaning techniques. In experiments with ITER-like castellation, the gaps were cleaned from carbonaceous deposits using oxygen plasmas at 350 deg. C. This contribution contains an overview of experimental and modeling results along with recommendations for PFCs in ITER.

Selection of criterions of fuels incineration on heat power plants

International Nuclear Information System (INIS)

Bubnov, V.P.; Minchenko, E.M.; Zelenukho, E.V.

2006-01-01

Fuel and energy complex takes first place in industry field of cities and defines in many respects environmental situation of cities. The products of combustion of fuel bring the greatest contribution in environmental contamination. This factor is ignored during calculation of technical and economics indexes. Ecological impact of heat power plants on the environment is determined separately from assessment of ecological damage. Determination of optimal conditions of functioning of heat power plants incineration with respect to technical, economics and ecological indexes with use of multicriterion mathematics model is proposed. (authors)

Gas Temperature and Radiative Heat Transfer in Oxy-fuel Flames

DEFF Research Database (Denmark)

Bäckström, Daniel; Johansson, Robert; Andersson, Klas

This work presents measurements of the gas temperature, including fluctuations, and its influence on the radiative heat transfer in oxy-fuel flames. The measurements were carried out in the Chalmers 100 kW oxy-fuel test unit. The in-furnace gas temperature was measured by a suction pyrometer...... on the radiative heat transfer shows no effect of turbulence-radiation interaction. However, by comparing with temperature fluctuations in other flames it can be seen that the fluctuations measured here are relatively small. Further research is needed to clarify to which extent the applied methods can account...

Heat pipes and solid sorption transformations fundamentals and practical applications

CERN Document Server

Vasiliev, LL

2013-01-01

Developing clean energy and utilizing waste energy has become increasingly vital. Research targeting the advancement of thermally powered adsorption cooling technologies has progressed in the past few decades, and the awareness of fuel cells and thermally activated (heat pipe heat exchangers) adsorption systems using natural refrigerants and/or alternatives to hydrofluorocarbon-based refrigerants is becoming ever more important. Heat Pipes and Solid Sorption Transformations: Fundamentals and Practical Applications concentrates on state-of-the-art adsorption research and technologies for releva

WORKING PARK-FUEL CELL COMBINED HEAT AND POWER SYSTEM

Energy Technology Data Exchange (ETDEWEB)

Allan Jones

2003-09-01

This report covers the aims and objectives of the project which was to design, install and operate a fuel cell combined heat and power (CHP) system in Woking Park, the first fuel cell CHP system in the United Kingdom. The report also covers the benefits that were expected to accrue from the work in an understanding of the full technology procurement process (including planning, design, installation, operation and maintenance), the economic and environmental performance in comparison with both conventional UK fuel supply and conventional CHP and the commercial viability of fuel cell CHP energy supply in the new deregulated energy markets.

An examination of flame shape related to convection heat transfer in deep-fuel beds

Science.gov (United States)

Kara M. Yedinak; Jack D. Cohen; Jason M. Forthofer; Mark A. Finney

2010-01-01

Fire spread through a fuel bed produces an observable curved combustion interface. This shape has been schematically represented largely without consideration for fire spread processes. The shape and dynamics of the flame profile within the fuel bed likely reflect the mechanisms of heat transfer necessary for the pre-heating and ignition of the fuel during fire spread....

Hybrid heat pipe based passive cooling device for spent nuclear fuel dry storage cask

International Nuclear Information System (INIS)

Jeong, Yeong Shin; Bang, In Cheol

2016-01-01

Highlights: • Hybrid heat pipe was presented as a passive cooling device for dry storage cask of SNF. • A method to utilize waste heat from spent fuel was suggested using hybrid heat pipe. • CFD analysis was performed to evaluate the thermal performance of hybrid heat pipe. • Hybrid heat pipe can increase safety margin and storage capacity of the dry storage cask. - Abstract: Conventional dry storage facilities for spent nuclear fuel (SNF) were designed to remove decay heat through the natural convection of air, but this method has limited cooling capacity and a possible re-criticality accident in case of flooding. To enhance the safety and capacity of dry storage cask of SNF, hybrid heat pipe-based passive cooling device was suggested. Heat pipe is an excellent passive heat transfer device using the principles of both conduction and phase change of the working fluid. The heat pipe containing neutron absorber material, the so-called hybrid heat pipe, is expected to prevent the re-criticality accidents of SNF and to increase the safety margin during interim and long term storage period. Moreover, a hybrid heat pipe with thermoelectric module, a Stirling engine and a phase change material tank can be used for utilization of the waste heat as heat-transfer medium. Located at the guide tube or instrumentation tube, hybrid heat pipe can remove decay heat from inside the sealed metal cask to outside, decreasing fuel rod temperature. In this paper, a 2-step analysis was performed using computational fluid dynamics code to evaluate the heat and fluid flow inside a cask, which consisted of a single spent fuel assembly simulation and a full-scope dry cask simulation. For a normal dry storage cask, the maximum fuel temperature is 290.0 °C. With hybrid heat pipe cooling, the temperature decreased to 261.6 °C with application of one hybrid heat pipe per assembly, and to 195.1 °C with the application of five hybrid heat pipes per assembly. Therefore, a dry

New approaches to the modelling of multi-component fuel droplet heating and evaporation

KAUST Repository

Sazhin, Sergei S

2015-02-25

The previously suggested quasi-discrete model for heating and evaporation of complex multi-component hydrocarbon fuel droplets is described. The dependence of density, viscosity, heat capacity and thermal conductivity of liquid components on carbon numbers n and temperatures is taken into account. The effects of temperature gradient and quasi-component diffusion inside droplets are taken into account. The analysis is based on the Effective Thermal Conductivity/Effective Diffusivity (ETC/ED) model. This model is applied to the analysis of Diesel and gasoline fuel droplet heating and evaporation. The components with relatively close n are replaced by quasi-components with properties calculated as average properties of the a priori defined groups of actual components. Thus the analysis of the heating and evaporation of droplets consisting of many components is replaced with the analysis of the heating and evaporation of droplets consisting of relatively few quasi-components. It is demonstrated that for Diesel and gasoline fuel droplets the predictions of the model based on five quasi-components are almost indistinguishable from the predictions of the model based on twenty quasi-components for Diesel fuel droplets and are very close to the predictions of the model based on thirteen quasi-components for gasoline fuel droplets. It is recommended that in the cases of both Diesel and gasoline spray combustion modelling, the analysis of droplet heating and evaporation is based on as little as five quasi-components.

An analysis of heating fuel market behavior, 1989--1990

Energy Technology Data Exchange (ETDEWEB)

1990-06-01

The purpose of this report is to fully assess the heating fuel crisis from a broader and longer-term perspective. Using EIA final, monthly data, in conjunction with credible information from non-government sources, the pricing phenomena exhibited by heating fuels in late December 1989 and early January 1990 are described and evaluated in more detail and more accurately than in the interim report. Additionally, data through February 1990 (and, in some cases, preliminary figures for March) make it possible to assess the market impact of movements in prices and supplies over the heating season as a whole. Finally, the longer time frame and the availability of quarterly reports filed with the Securities and Exchange Commission make it possible to weigh the impact of revenue gains in December and January on overall profits over the two winter quarters. Some of the major, related issues raised during the House and Senate hearings in January concerned the structure of heating fuel markets and the degree to which changes in this structure over the last decade may have influenced the behavior and financial performance of market participants. Have these markets become more concentrated Was collusion or market manipulation behind December's rising prices Did these, or other, factors permit suppliers to realize excessive profits What additional costs were incurred by consumers as a result of such forces These questions, and others, are addressed in the course of this report.

Progress performance report of clean uses of fossil fuels

Energy Technology Data Exchange (ETDEWEB)

Todd, Jr., Lee T.; Boggess, Ronald J.; Carson, Ronald J.; Falkenberg, Virginia P.; Flanagan, Patrick; Hettinger, Jr., William P.; Kimel, Kris; Kupchella, Charles E.; Magid, Lee J.; McLaughlin, Barbara; Royster, Wimberly C.; Streepey, Judi L.; Wells, James H.; Stencel, John; Derbyshire, Frank J.; Hanley, Thomas R.; Magid, Lee J.; McEllistrem, Marc T.; Riley, John T.; Steffen, Joseph M.

1992-01-01

A one-year USDOE/EPSCOR Traineeship Grant, entitled Clean Uses of Fossil Fuels.'' was awarded to the Kentucky EPSCoR Committee in September 1991 and administered through the the DOE/EPSCoR Subcommittee. Ten Traineeships were awarded to doctoral students who are enrolled or accepted into Graduate Programs at either the University of Kentucky or the University of Louisville. The disciplines of these students include Biology, Chemical Engineering, Chemistry, Geological Sciences, and Physics. The methods used for a statewide proposal solicitation and to award the Traineeships are presented. The review panel and Kentucky DOE/EPSCoR Subcommittee involved in awarding the Traineeships are described. A summary of the proposed research to be performed within these awards is presented, along with a description of the qualifications of the faculty and students who proposed projects. Future efforts to increase participation in Traineeship proposals for the succeeding funding period are outlined.

Progress performance report of clean uses of fossil fuels

Energy Technology Data Exchange (ETDEWEB)

1992-09-01

A one-year USDOE/EPSCOR Traineeship Grant, entitled ``Clean Uses of Fossil Fuels.`` was awarded to the Kentucky EPSCoR Committee in September 1991 and administered through the the DOE/EPSCoR Subcommittee. Ten Traineeships were awarded to doctoral students who are enrolled or accepted into Graduate Programs at either the University of Kentucky or the University of Louisville. The disciplines of these students include Biology, Chemical Engineering, Chemistry, Geological Sciences, and Physics. The methods used for a statewide proposal solicitation and to award the Traineeships are presented. The review panel and Kentucky DOE/EPSCoR Subcommittee involved in awarding the Traineeships are described. A summary of the proposed research to be performed within these awards is presented, along with a description of the qualifications of the faculty and students who proposed projects. Future efforts to increase participation in Traineeship proposals for the succeeding funding period are outlined.

Clean Cities Annual Metrics Report 2006

Energy Technology Data Exchange (ETDEWEB)

Bergeron, P.; Putsche, V.

2007-07-01

Report summarizes Clean Cities coalition accomplishments, including membership, funding, sales of alternative fuel blends, deployment of AFVs and HEVs, idle reduction initiatives, and fuel economy activities.

Alternative Fuel News: Official Publication of the U.S. Department of Energy's Clean Cities Network and the Alternative Fuels Data Center; Vol. 5, No. 1

Energy Technology Data Exchange (ETDEWEB)

LaRocque, T.

2001-04-18

A quarterly magazine with articles on recent changes to the Clean Cities Program; the SuperTruck student engineering challenge; alternative fuel use in delivery fleets; and a propane vehicle rally and conference in February 2001, in Kansas City, Mo.

Universal high-temperature heat treatment furnace for FBR mixed uranium and plutonium carbide fuel

International Nuclear Information System (INIS)

Handa, Muneo; Takahashi, Ichiro; Watanabe, Hitoshi

1978-10-01

A universal high-temperature heat treatment furnace for LMFBR advanced fuels was installed in Plutonium Fuel Laboratory, Oarai Research Establishment. Design, construction and performance of the apparatus are described. With the apparatus, heat treatment of the fuel under a controlled gas atmosphere and quenching of the fuel with blowing helium gas are possible. Equipment to measure impurity gas release of the fuel is also provided. Various plutonium enclosure techniques, e.g., a gas line filter with new exchange mechanics, have been developed. In performance test, results of the enclosure techniques are described. (author)

Clean utilization of coal

International Nuclear Information System (INIS)

Yueruem, Y.

1992-01-01

This volume contains 23 lectures presented at the Advanced Study Institute on 'Chemistry and Chemical Engineering of Catalytic Solid Fuel Conversion for the Production of Clean Synthetic Fuels', which was held at Akcay, Edremit, Turkey, between 21 July and August 3, 1991. Three main subjects: structure and reactivity of coal; cleaning of coal and its products, and factors affecting the environmental balance of energy usage and solutions for the future, were discussed in the Institute and these are presented under six groups in the book: Part 1. Structure and reactivity of coal; Part 2. Factors affecting environmental balance; Part 3. Pre-usage cleaning operations and processes; Part 4. Upgrading of coal liquids and gases; Part 5. Oxygen enriched processes; and Part 6. Probable future solution for energy and pollution problems. Separate abstracts have been prepared for all the lectures

Laser pulse heating of nuclear fuels for simulation of reactor power

Indian Academy of Sciences (India)

Laser applications; nuclear fuel elements; nuclear safety. ... accident (LOCA) and reactivity initiated accident (RIA), a laser pulse heating system is under ... As a prelude to work on irradiated nuclear fuel specimens, pilot studies on unirradiated ...

Supply of fossil heating and motor fuels

International Nuclear Information System (INIS)

Kaegi, W.; Siegrist, S.; Schaefli, M.; Eichenberger, U.

2003-01-01

This comprehensive study made for the Swiss Federal Office of Energy (SFOE) within the framework of the Energy Economics Fundamentals research programme examines if it can be guaranteed that Swiss industry can be supplied with fossil fuels for heating and transport purposes over the next few decades. The results of a comprehensive survey of literature on the subject are presented, with a major focus being placed on oil. The study examines both pessimistic and optimistic views and also presents an overview of fossil energy carriers and the possibilities of substituting them. Scenarios and prognoses on the availability of fossil fuels and their reserves for the future are presented. Also, new technologies for exploration and the extraction of fossil fuels are discussed, as are international interdependencies that influence supply. Market and price scenarios are presented that take account of a possible increasing scarcity of fossil fuels. The implications for industry and investment planning are examined

Method of storing the fuel storage pot in a fuel storage tank for away-from-reactor-storage

International Nuclear Information System (INIS)

Ishiguro, Jun-ichi.

1980-01-01

Purpose: To prevent the contact of sodium in the away-from-reactor-storage fuel storage tank with sodium in a fuel storage pool having radioactivity ana always retain clean state therein. Method: Sodium is filled in a container body of the away-from-reactor-storage fuel storage tank, and a conduit, a cycling pump, and cooling means are disposed to form a sodium coolant cycling loop. The fuel storage pool is so stored in the container body that the heat of the pool is projected from the liquid surface of the sodium in the container. Therefore, the sodium in the container is isolated from the sodium in the pool containing strong radioactivity to prevent contact of the former sodium from the latter sodium. (Sekiya, K.)

Airflow Obstruction and Use of Solid Fuels for Cooking or Heating: BOLD Results.

Science.gov (United States)

Amaral, André F S; Patel, Jaymini; Kato, Bernet S; Obaseki, Daniel O; Lawin, Hervé; Tan, Wan C; Juvekar, Sanjay K; Harrabi, Imed; Studnicka, Michael; Wouters, Emiel F M; Loh, Li-Cher; Bateman, Eric D; Mortimer, Kevin; Buist, A Sonia; Burney, Peter G J

2017-09-12

Evidence supporting the association of COPD or airflow obstruction with use of solid fuels is conflicting and inconsistent. To assess the association of airflow obstruction with self-reported use of solid fuels for cooking or heating. We analysed 18,554 adults from the BOLD study, who had provided acceptable post-bronchodilator spirometry measurements and information on use of solid fuels. The association of airflow obstruction with use of solid fuels for cooking or heating was assessed by sex, within each site, using regression analysis. Estimates were stratified by national income and meta-analysed. We carried out similar analyses for spirometric restriction, chronic cough and chronic phlegm. We found no association between airflow obstruction and use of solid fuels for cooking or heating (ORmen=1.20, 95%CI 0.94-1.53; ORwomen=0.88, 95%CI 0.67-1.15). This was true for low/middle and high income sites. Among never smokers there was also no evidence of an association of airflow obstruction with use of solid fuels (ORmen=1.00, 95%CI 0.57-1.76; ORwomen=1.00, 95%CI 0.76-1.32). Overall, we found no association of spirometric restriction, chronic cough or chronic phlegm with the use of solid fuels. However, we found that chronic phlegm was more likely to be reported among female never smokers and those who had been exposed for ≥20 years. Airflow obstruction assessed from post-bronchodilator spirometry was not associated with use of solid fuels for cooking or heating.

Impacts of the Weatherization Assistance Program in fuel-oil heated houses

Energy Technology Data Exchange (ETDEWEB)

Levins, W.P.; Ternes, M.P.

1994-10-01

In 1990, the US Department of Energy (DOE) initiated a national evaluation of its lowincome Weatherization Assistance Program. This report, which is one of five parts of that evaluation, evaluates the energy savings and cost-effectiveness of the Program as it had been applied to single-family houses heated primarily by fuel-oil. The study was based upon a representative sample (41 local weatherization agencies, 222 weatherized and 115 control houses) from the nine northeastern states during 1991 and 1992 program years. Dwelling-specific and agency-level data on measures installed, costs, and service delivery procedures were collected from the sampled agencies. Space-heating fuel-oil consumption, indoor temperature, and outdoor temperature were monitored at each house. Dwelling characteristics, air-leakage measurements, space-heating system steady-state efficiency measurements, safety inspections, and occupant questionnaires were also collected or performed at each monitored house. We estimate that the Program weatherized a total of 23,400 single-family fuel-oil heated houses in the nine northeastern states during program years 1991 and 1992. Annual fuel-oil savings were calculated using regression techniques to normalize the savings to standard weather conditions. For the northeast region, annual net fuel-oil savings averaged 160 gallons per house, or 17.7% of pre-weatherization consumption. Although indoor temperatures changed in individual houses following weatherization, there was no average change and no significant difference as compared to the control houses; thus, there was no overall indoor temperature takeback effect influencing fuel-oil savings. The weatherization work was performed cost effectively in these houses from the Program perspective, which included both installation costs and overhead and management costs but did not include non-energy benefits (such as employment and environmental).

Transient non-boiling heat transfer in a fuel rod bundle during accidental power excursions

International Nuclear Information System (INIS)

Bonaekdarzadeh, S.; Johannsen, K.; Ramm, H.

1977-01-01

The physical problem studied is the transient non-boiling heat transfer of a cylindrical fuel rod consisting of fuel, gap, and cladding to a steady, fully developed turbulent flow. The fuel pin is assumed to be located in the interior region of a subassembly with regular triangular or square arrangements. The turbulent velocity field as well as turbulent transport properties are specified as functions of the coordinates normal to the axial flow direction. The heat generation within the fuel may be specified as an arbitrary function of the three spatial coordinates and time. A digital computer program has been developed. On the basis of finite-difference techniques, to solve the governing partial differential equations with their associated subsidiary conditions. Results have been obtained for a series of exponential power transients of interest to safety of liquid-metal and water cooled nuclear reactors. The general physical features of transient convective heat transfer as explored by previous investigators have qualitatively been substantiated by the present analysis. Emphasis has been devoted to investigate the differences of heat-transfer (coefficient) results from multi-region analysis including a realistic fuel rod model and single-region analysis for the coolant region only. A comparison with the engineering relationships for turbulent liquid-metal cooling by Stein, which are an extension of the heat transfer coefficient concept to account for transient heat fluxes, clearly demonstrates that, at the parameters studied, Stein's approach tends to largely overestimate the convective heat transfer at early times

PORTABLE PEM FUEL CELL SYSTEM: WATER AND HEAT MANAGEMENT

Directory of Open Access Journals (Sweden)

SITI NAJIBAH ABD RAHMAN

2016-07-01

Full Text Available Portable polymer electrolyte membrane (PEM fuel cell power generator is a PEM fuel cell application that is used as an external charger to supply the demand for high energy. Different environments at various ambient temperatures and humidity levels affect the performance of PEM fuel cell power generators. Thermal and water management in portable PEM fuel cells are a critical technical barrier for the commercialization of this technology. The size and weight of the portable PEM fuel cells used for thermal and water management systems that determine the performance of portable PEM fuel cells also need to be considered. The main objective of this paper review was to determine the importance of water and thermal management systems in portable PEM fuel cells. Additionally, this review investigated heat transfer and water transport in PEM fuel cells. Given that portable PEM fuel cells with different powers require different thermal and water management systems, this review also discussed and compared management systems for low-, medium-, and high-power portable PEM fuel cells.

Development of dedicated nuclear heating plants in the Federal Republic of Germany

International Nuclear Information System (INIS)

Goetzmann, C.A.; Schroeter, K.E.

1987-01-01

In many cases district heating is both economically and environmentally superior over directly burning of fossil fuels in individual furnaces primarily because of the efficiency of the usual applied co-generation principle with regard to fuel utilization and flue gas clean up. In principle, this argument should carry even greater weight in conjunction with nuclear energy. The major draw back of dedicated heating reactors as seen up to now concerns the high specific capital cost for the application-dictated small reactor size. The paper discusses by way of a specific example in what directions solutions are being sought. (author)

Development of dedicated nuclear heating plants in the Federal Republic of Germany

International Nuclear Information System (INIS)

Goetzmann, C.A.; Schroeter, K.E.

1988-01-01

In many cases district heating is both economically and environmentally superior over directly burning of fossil fuels in individual furnaces primarily because of the efficiency of the usual applied co-generation principle with regard to fuel utilization and flue gas clean up. In principle, this argument should carry even greater weight in conjunction with nuclear energy. The major draw back of dedicated heating reactors as seen up to now concerns the high specific capital cost for the application-dictated small reactor size. The paper discusses by way of a specific example in what directions solutions are being sought

ENVIRONMENTAL TECHNOLOGY VERIFICATION, TEST REPORT OF MOBILE SOURCE EMISSIONS CONTROL DEVICES: CLEAN DIESEL TECHNOLOGIES FUEL-BORNE CATALYST WITH MITSUI/PUREARTH CATALYZED WIRE MESH FILTER

Science.gov (United States)

The Environmental Technology Verification report discusses the technology and performance of the Fuel-Borne Catalyst with Mitsui/PUREarth Catalyzed Wire Mesh Filter manufactured by Clean Diesel Technologies, Inc. The technology is a platinum/cerium fuel-borne catalyst in commerci...

Process of heat-treating fuels of a bituminous nature, such as shale

Energy Technology Data Exchange (ETDEWEB)

Bergh, S V

1927-11-25

A process is described of heat treating any kind of material of a bituminous nature usable as fuel, like shale, mineral coal, peat, etc., whereby the fuel undergoes in a retort or the like a distillation for recovering from it the total amount or the greatest part of gaseous or vaporous distillation products. The warm distillation residue is burned, characterized by the retorts, containing the fuel going through, being wholly or partly surrounded by materials to be heated. These materials and the warm distillation residue resulting from the distillation during the burning are moved forward independently one of the other.

C1 CHEMISTRY FOR THE PRODUCTION OF ULTRA-CLEAN LIQUID TRANSPORTATION FUELS AND HYDROGEN

Energy Technology Data Exchange (ETDEWEB)

Gerald P. Huffman

2003-09-30

The Consortium for Fossil Fuel Science (CFFS) is a research consortium with participants from the University of Kentucky, University of Pittsburgh, University of Utah, West Virginia University, and Auburn University. The CFFS is conducting a research program to develop C1 chemistry technology for the production of clean transportation fuel from resources such as coal and natural gas, which are more plentiful domestically than petroleum. The processes under development will convert feedstocks containing one carbon atom per molecular unit into ultra clean liquid transportation fuels (gasoline, diesel, and jet fuel) and hydrogen, which many believe will be the transportation fuel of the future. These feedstocks include synthesis gas, a mixture of carbon monoxide and hydrogen produced by coal gasification or reforming of natural gas, methane, methanol, carbon dioxide, and carbon monoxide. Some highlights of the results obtained during the first year of the current research contract are summarized as: (1) Terminal alkynes are an effective chain initiator for Fischer-Tropsch (FT) reactions, producing normal paraffins with C numbers {ge} to that of the added alkyne. (2) Significant improvement in the product distribution towards heavier hydrocarbons (C{sub 5} to C{sub 19}) was achieved in supercritical fluid (SCF) FT reactions compared to that of gas-phase reactions. (3) Xerogel and aerogel silica supported cobalt catalysts were successfully employed for FT synthesis. Selectivity for diesel range products increased with increasing Co content. (4) Silicoaluminophosphate (SAPO) molecular sieve catalysts have been developed for methanol to olefin conversion, producing value-added products such as ethylene and propylene. (5) Hybrid Pt-promoted tungstated and sulfated zirconia catalysts are very effective in cracking n-C{sub 36} to jet and diesel fuel; these catalysts will be tested for cracking of FT wax. (6) Methane, ethane, and propane are readily decomposed to pure

Dimensional Behavior of Matrix Graphite Compacts during Heat Treatments for HTGR Fuel Element Fabrication

International Nuclear Information System (INIS)

Lee, Young-Woo; Yeo, Seunghwan; Cho, Moon Sung

2015-01-01

The carbonization is a process step where the binder that is incorporated during the matrix graphite powder preparation step is evaporated and the residue of the binder is carbonized during the heat treatment at about 1073 K. This carbonization step is followed by the final high temperature heat treatment where the carbonized compacts are heat treated at 2073-2173 K in vacuum for a relatively short time (about 2 hrs). In order to develop a fuel compact fabrication technology, and for fuel matrix graphite to meet the required material properties, it is essential to investigate the relationship among the process parameters of the matrix graphite powder preparation, the fabrication parameters of fuel element green compact and the heat treatments conditions, which has a strong influence on the further steps and the material properties of fuel element. In this work, the dimensional changes of green compacts during the carbonization and final heat treatment are evaluated when compacts have different densities from different pressing conditions and different final heat treatment temperatures are employed, keeping other process parameters constant, such as the binder content, carbonization time, temperature and atmosphere (two hours ant 1073K and N2 atmosphere). In this work, the dimensional variations of green compacts during the carbonization and final heat treatment are evaluated when compacts have different densities from different pressing conditions and different final heat treatment temperatures are employed

Study of a molten carbonate fuel cell combined heat, hydrogen and power system

International Nuclear Information System (INIS)

Hamad, Tarek A.; Agll, Abdulhakim A.; Hamad, Yousif M.; Bapat, Sushrut; Thomas, Mathew; Martin, Kevin B.; Sheffield, John W.

2014-01-01

To address the problem of fossil fuel usage and high greenhouse gas emissions at the Missouri University of Science and Technology campus, using of alternative fuels and renewable energy sources can lower energy consumption and greenhouse gas emissions. Biogas, produced by anaerobic digestion of wastewater, organic waste, agricultural waste, industrial waste, and animal by-products is a potential source of renewable energy. In this work, we have discussed the design of CHHP (combined heat, hydrogen and power) system for the campus using local resources. An energy flow and resource availability study is performed to identify the type and source of feedstock required to continuously run the fuel cell system at peak capacity. Following the resource assessment study, the team selects FuelCell Energy DFC (direct fuel cell) 1500™ unit as a molten carbonate fuel cell. The CHHP system provides electricity to power the university campus, thermal energy for heating the anaerobic digester, and hydrogen for transportation, back-up power and other needs. In conclusion, the CHHP system will be able to reduce fossil fuel usage, and greenhouse gas emissions at the university campus. - Highlights: • A molten carbonate fuel cell tri-generation by using anaerobic digestion system. • Anaerobic digestion system will be able to supply fuel for the DFC1500™ unit. • Use locally available feedstock to production electric power, hydrogen and heat. • Application energy end-uses on the university. • CHHP system will reduce energy consumption, fossil fuel usage, and GHG emissions

A local heating system using wood fuel from farms

International Nuclear Information System (INIS)

Kiukaanniemi, E.; Kurvinen, T.

1998-01-01

This report is a part of the a project on sustainable biomass utilization chains. The project belongs to a larger group of studies on northern biomass utilization by the Thule Institute and the University of Oulu. A cooperative energy society working in the municipality of Perho (3400 inhabitants) in Finland has been studied in this report. The cooperative energy society delivers energy which is generated from wood chips to the Perho municipality. Generated energy has a competitive price compared with fuel oils. In addition, harvesting, chipping and transporting give the members of the society an extra income. Members need not to make any investments in new equipment in order to work in the co-operative society because the machinery needed is the same as the one they use for other forestry activities. The price of the energy generated by wood chips is bound to the price of alternative fuels. There is a 5 MW district heating plant in Perho municipality containing a 1.4 MW solid fuel fired boiler with grate and 1.6 MW and 2.0 MW oil fired boilers. An investment in a heating plant containing a solid fuel fired boiler is often many times greater than that of one containing an oil fired boiler. There are many advantages which are hard to evaluate in generating energy from wood fuel. E.g. employment, increased income from taxes, an increase in the cash flow in the municipality and the advantages for forest growth. When undersized trees are removed from a forest stand, the remaining trees will grow better. The advantage of forestry is, however, hard to evaluate in cash terms. There has been an estimate that the advantage is 50-100 FIM/ha/a when compared to the yield of unthinned pine forest. Studies have shown that the money paid for energy in the area may be recycled several times in purchasing products and services in the area. In Perho municipality, it has been estimated that over half million FIM of extra cash has been generated and invested in the area by the

An experimental investigation of heat transfer from a reactor fuel channel to surrounding water

International Nuclear Information System (INIS)

Gillespie, G.E.

An important feature of the CANDU-PHW reactor is that each fuel channel is surrounded by cool heavy-water moderator that can act as a sink for heat generated in the fuel if other means of heat removal were to fail. During postulated loss-of-coolant accidents there are two scenarios in which the primary cooling system may not prevent fuel-channel overheating. These situations arise when: (1) for a particular break size and location, called the critical break, the coolant flow through a portion of the reactor core stagnates before the emergency coolant injection system restores circulation, or, (2) the emergency coolant injection system fails to operate. In either case, the heat generated in the fuel is transferred mainly by radiation to the pressure tube and calandria tube, and then by boiling heat transfer to the moderator. This paper describes a simple one-dimensional model developed to analyse the thermal behaviour of a fuel channel when the internal pressure is high. Also described is a series of experiments in which the pressure-tube segment is pressurized and heated at a constant rate until it contacts a surrounding calandria-tube segment. Predictions of the one-dimensional model are compared with the experimental results

Development of a water boil-off spent-fuel calorimeter system. [To measure decay heat generation rate

Energy Technology Data Exchange (ETDEWEB)

Creer, J.M.; Shupe, J.W. Jr.

1981-05-01

A calorimeter system was developed to measure decay heat generation rates of unmodified spent fuel assemblies from commercial nuclear reactors. The system was designed, fabricated, and successfully tested using the following specifications: capacity of one BWR or PWR spent fuel assembly; decay heat generation range 0.1 to 2.5 kW; measurement time of < 12 h; and an accuracy of +-10% or better. The system was acceptance tested using a dc reference heater to simulate spent fuel assembly heat generation rates. Results of these tests indicated that the system could be used to measure heat generation rates between 0.5 and 2.5 kW within +- 5%. Measurements of heat generation rates of approx. 0.1 kW were obtained within +- 15%. The calorimeter system has the potential to permit measurements of heat generation rates of spent fuel assemblies and other devices in the 12- to 14-kW range. Results of calorimetry of a Turkey Point spent fuel assembly indicated that the assembly was generating approx. 1.55 kW.

Clean Cities Annual Metrics Report 2009 (Revised)

Energy Technology Data Exchange (ETDEWEB)

Johnson, C.

2011-08-01

Document provides Clean Cities coalition metrics about the use of alternative fuels; the deployment of alternative fuel vehicles, hybrid electric vehicles (HEVs), and idle reduction initiatives; fuel economy activities; and programs to reduce vehicle miles driven.

Heat split imbalance study for annular fuel rod

International Nuclear Information System (INIS)

He Xiaojun; Ji Songtao; Zhang Yingchao

2014-01-01

Annular fuel rod has two gaps at inner and outer side. Under irradiation condition, the dimensional change of pellets is always larger than claddings' due to thermal expansion, swelling and densification, and this tends to enlarge the inner gap and reduce the outer gap. The gap size asymmetry must induce heat split imbalance problem that the heat flux will be larger at outer side of the rod. In this work, computer code AFPAC l.0 is used to simulate this heat split imbalance phenomena. The effect of initial gap size, rod inner pressure, roughness of pellets and cladding is studied, the results reveal that: l) Adjusting initial size of both gaps, reducing inner gap and enlarging outer gap could effectively alleviate heat split imbalance problem; 2) Adjusting the initial roughness of pellets and cladding is another effective approach to reducing heat split imbalance; 3) It seems that changing the rod inner pressure has a little effect on solving the heat flux asymmetry problem. (authors)

Clean Cities 2015 Annual Metrics Report

Energy Technology Data Exchange (ETDEWEB)

Johnson, Caley [National Renewable Energy Lab. (NREL), Golden, CO (United States); Singer, Mark [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-12-01

The U.S. Department of Energy's (DOE's) Clean Cities program advances the nation's economic, environmental, and energy security by supporting local actions to cut petroleum use and greenhouse gas (GHG) emissions in transportation. A national network of nearly 100 Clean Cities coalitions, whose territory covers 80% of the U.S. population, brings together stakeholders in the public and private sectors to deploy alternative and renewable fuels, idle-reduction (IR) measures, fuel economy improvements, and new transportation technologies as they emerge. Each year, DOE asks Clean Cities coordinators to submit annual reports of their activities and accomplishments for the previous calendar year. Progress reports and information are submitted online as a function of the Alternative Fuels Data Center (AFDC) at the National Renewable Energy Laboratory (NREL). Coordinators report a range of information that characterize the membership, funding, projects, and activities of their coalitions. They also document activities in their region related to the development of refueling/charging infrastructure, sales of alternative fuels; deployment of alternative fuel vehicles (AFVs), plug-in electric vehicles (PEVs), hybrid electric vehicles (HEVs), and plug-in hybrid electric vehicles (PHEVs); idle reduction initiatives; fuel economy improvement activities; and programs to reduce vehicle miles traveled (VMT). NREL analyzes the data and translates them into petroleum-use and GHG emission reduction impacts, which are summarized in this report.

Cleaning of the heat exchanger, Task 3.08/04-01; Zadatak 3.08/04-01 - Ciscenje razmenjivaca toplote

Energy Technology Data Exchange (ETDEWEB)

Nikolic, M; Bratic, A; Milosevic, M [Institute of Nuclear Sciences Boris Kidric, Reaktor RA, Vinca, Beograd (Serbia and Montenegro)

1963-12-15

A problem of decreased cooling appeared after longer operation of the reactor at nominal power of 6.5 MW. The reason of increased coolant temperature in the primary coolant loop and lower temperatures in the secondary coolant loop indicated problems to be related to heat exchangers. Deposits of sand and sludge in the secondary coolant pipes caused decrease of he flow, i.e. decrease of the effective surface for heat exchange. Cleaning of the heat exchanger pipes demanded detailed radiation protection plan to avoid higher exposure of the 74 staff members involved in the operation.

The convenient truth LPG: clean energy for a low carbon world

International Nuclear Information System (INIS)

Rolland, M.

2008-01-01

In the context of climate change, no one solution is future-proof. It is going to take a coordinated worldwide effort to find the right mix of energy policies while balancing diverse and sometimes competing priorities. The WLPGA Climate Change Working Group (CCWG) seeks to demonstrate that the technologies needed to continue current rates of development while mitigating climate change already exist and that LP gas can be a major part of today's solutions to this challenge. LP gas is not a zero-GHG fuel. However, in most cases it can make major and immediate contributions to delivering real GHG emissions reductions. In some ways LP Gas can claim to be ahead of its time, for its clean-burning, low-carbon advantage is available at once, so that even using today's technology, most industries can exceed Kyoto GHG reduction targets by switching to LP Gas. The fact is that LP Gas produces lower GHG emissions compared to conventional energy supplies in virtually every application it is used, from stationary applications such as water heating, space heating, cooking and industrial boilers to transportation applications. There are opportunities to switch to clean burning LP gas for virtually every industry as a means meet GHG targets. LP gas is also portable, making it a perfect complement to distributed renewable energy source such as solar, wind and wave energy (and soon the fuel cell), thereby reducing our reliance centrally produced electricity. LP Gas used in combination with these renewable sources also can improve energy reliability while reducing the overall life-cycle costs. The portable and clean burning nature of LP Gas also makes it an ideal substitute for solid fuels in domestic cooking and heating applications. Household solid fuel use, overwhelmingly concentrated in developing countries, accounts for up to 30% of black carbon emissions worldwide according to some statistics. Switching to LP Gas could lower global GHG emissions as well as help to diminish

Heat and mass transfer analysis intermediate temperature solid oxide fuel cells (IT-SOFC)

International Nuclear Information System (INIS)

Timurkutluk, B.; Mat, M. M.; Kaplan, Y.

2007-01-01

Solid oxide fuel cells (SOFCs) have been considered as next generation energy conversion system due to their high efficiency, clean and quite operation with fuel flexibility. To date, yittria stabilized zirconia (YSZ) electrolytes have been mainly used for SOFC applications at high temperatures around 1000 degree C because of their high ionic conductivity, chemical stability and good mechanical properties. However, such a high temperature is undesirable for fuel cell operations in the viewpoint of stability. Moreover, high operation temperature necessitates high cost interconnect and seal materials. Thus, the reduction in the operation temperature of SOFCs is one of the key issues in the aspects of the cost reduction and the long term operation without degradation as well as commercialization of the SOFC systems. With the reducing temperature, not only low cost stainless steels and glass materials can be used as interconnect and sealing materials respectively but the manufacturing technology will also extend. Therefore, the design of complex geometrical SOFC component will also be possible. One way to reduce the operation temperature of SOFC is use of an alternative electrolyte material to YSZ showing acceptable properties at intermediate temperatures (600-800 degree C). As being one of IT-SOFC electrolyte materials, gadolinium doped ceria (GDC) has been taken great deals. In this study, a mathematical model for mass and heat transfer for a single cell GDC electrolyte SOFC system was developed and numerical solutions were evaluated. In order to verify the mathematical model, set of experiments were performed by taking species from four different samples randomly and five various temperature measurements. The numerical results reasonably agree with experimental data

Use of a commercial heat transfer code to predict horizontally oriented spent fuel rod surface temperatures

International Nuclear Information System (INIS)

Wix, S.D.; Koski, J.A.

1993-03-01

Radioactive spent fuel assemblies are a source of hazardous waste that will have to be dealt with in the near future. It is anticipated that the spent fuel assemblies will be transported to disposal sites in spent fuel transportation casks. In order to design a reliable and safe transportation cask, the maximum cladding temperature of the spent fuel rod arrays must be calculated. A comparison between numerical calculations using commercial thermal analysis software packages and experimental data simulating a horizontally oriented spent fuel rod array was performed. Twelve cases were analyzed using air and helium for the fill gas, with three different heat dissipation levels. The numerically predicted temperatures are higher than the experimental data for all levels of heat dissipation with air as the fill gas. The temperature differences are 4 degree C and 23 degree C for the low heat dissipation and high heat dissipation, respectively. The temperature predictions using helium as a fill gas are lower for the low and medium heat dissipation levels, but higher at the high heat dissipation. The temperature differences are 1 degree C and 6 degree C for the low and medium heat dissipation, respectively. For the high heat dissipation level, the temperature predictions are 16 degree C higher than the experimental data. Differences between the predicted and experimental temperatures can be attributed to several factors. These factors include experimental uncertainty in the temperature and heat dissipation measurements, actual convection effects not included in the model, and axial heat flow in the experimental data. This work demonstrates that horizontally oriented spent fuel rod surface temperature predictions can be made using existing commercial software packages. This work also shows that end effects will be increasingly important as the amount of dissipated heat increases

Heat transfer modelling in a spent-fuel dry storage system

International Nuclear Information System (INIS)

Ritz, J.B.; Le Bonhomme, S.

2001-01-01

The purpose of this paper is to present a numerical modelling of heat transfers in a Spent-Fuel horizontal dry storage. The horizontal dry storage is an interesting issue to momentary store spent fuel containers before the final storage. From a thermal point of view, the cooling of spent fuel container by natural convection is a suitable and inexpensive process but it necessitates to well define the dimensions of the concept due to the difficulty to control the thermal environment. (author)

Impacts of the Weatherization Assistance Program in Fuel-Oil Heated Houses

Energy Technology Data Exchange (ETDEWEB)

Levins, W.P.

1994-01-01

In 1990, the U.S. Department of Energy (DOE) initiated a national evaluation of its low-income Weatherization Assistance Program. This report, which is one of five parts of that evaluation, evaluates the energy savings and cost-effectiveness of the Program as it had been applied to single-family houses heated primarily by fuel-oil. The study was based upon a representative sample (41 local weatherization agencies, 222 weatherized and 115 control houses) from the nine northeastern states during 1991 and 1992 program years. Dwelling-specific and agency-level data on measures installed, costs, and service delivery procedures were collected from the sampled agencies. Space-heating fuel-oil consumption, indoor temperature, and outdoor temperature were monitored at each house. Dwelling characteristics, air-leakage measurements, space-heating system steady-state efficiency measurements, safety inspections, and occupant questionnaires were also collected or performed at each monitored house. We estimate that the Program weatherized a total of 23,400 single-family fuel-oil heated houses in the nine northeastern states during program years 1991 and 1992. Annual fuel-oil savings were calculated using regression techniques to normalize the savings to standard weather conditions. For the northeast region, annual net fuel-oil savings averaged 160 gallons per house, or 17.7% of pre-weatherization consumption. Although indoor temperatures changed in individual houses following weatherization, there was no average change and no significant difference as compared to the control houses; thus, there was no overall indoor temperature takeback effect influencing fuel-oil savings. The weatherization work was performed cost effectively in these houses from the Program perspective, which included both installation costs and overhead and management costs but did not include non-energy benefits (such as employment and environmental). Total average costs were $1819 per house ($1192 for

A new method for distribution of consumed heat in a fuel and costs in power and heating plants

Energy Technology Data Exchange (ETDEWEB)

Kadrnozka, J [Technical Univ., Brno (Czech Republic)

1993-09-01

There is described a new method for distribution of consumed heat in a fuel and costs in the power and heating plants, which is based on the relatively the same proportion of advantages followed from combine generation of electricity and heat on electricity and heat. The method is physically substantiated, it is very universal and it is applied for new types of power and heating plants and for distribution of investment costs and other costs. (orig./GL)

Heat and mass release for some transient fuel source fires: A test report

International Nuclear Information System (INIS)

Nowlen, S.P.

1986-10-01

Nine fire tests using five different trash fuel source packages were conducted by Sandia National Laboratories. This report presents the findings of these tests. Data reported includes heat and mass release rates, total heat and mass release, plume temperatures, and average fuel heat of combustion. These tests were conducted as a part of the US Nuclear Regulatory Commission sponsored fire safety research program. Data from these tests were intended for use in nuclear power plant probabilistic risk assessment fire analyses. The results were also used as input to a fire test program at Sandia investigating the vulnerability of electrical control cabinets to fire. The fuel packages tested were chosen to be representative of small to moderately sized transient trash fuel sources of the type that would be found in a nuclear power plant. The highest fire intensity encountered during these tests was 145 kW. Plume temperatures did not exceed 820 0 C

Sustainable development with clean coal

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-08-01

This paper discusses the opportunities available with clean coal technologies. Applications include new power plants, retrofitting and repowering of existing power plants, steelmaking, cement making, paper manufacturing, cogeneration facilities, and district heating plants. An appendix describes the clean coal technologies. These include coal preparation (physical cleaning, low-rank upgrading, bituminous coal preparation); combustion technologies (fluidized-bed combustion and NOx control); post-combustion cleaning (particulate control, sulfur dioxide control, nitrogen oxide control); and conversion with the integrated gasification combined cycle.

Developing clean fuels: Novel techniques for desulfurization

Science.gov (United States)

Nehlsen, James P.

The removal of sulfur compounds from petroleum is crucial to producing clean burning fuels. Sulfur compounds poison emission control catalysts and are the source of acid rain. New federal regulations require the removal of sulfur in both gasoline and diesel to very low levels, forcing existing technologies to be pushed into inefficient operating regimes. New technology is required to efficiently produce low sulfur fuels. Two processes for the removal of sulfur compounds from petroleum have been developed: the removal of alkanethiols by heterogeneous reaction with metal oxides; and oxidative desulfurization of sulfides and thiophene by reaction with sulfuric acid. Alkanethiols, common in hydrotreated gasoline, can be selectively removed and recovered from a hydrocarbon stream by heterogeneous reaction with oxides of Pb, Hg(II), and Ba. The choice of reactive metal oxides may be predicted from simple thermodynamic considerations. The reaction is found to be autocatalytic, first order in water, and zero order in thiol in the presence of excess oxide. The thiols are recovered by reactive extraction with dilute oxidizing acid. The potential for using polymer membrane hydrogenation reactors (PEMHRs) to perform hydrogenation reactions such as hydrodesulfurization is explored by hydrogenating ketones and olefins over Pt and Au group metals. The dependence of reaction rate on current density suggests that the first hydrogen addition to the olefin is the rate limiting step, rather than the adsorption of hydrogen, for all of the metals tested. PEMHRs proved unsuccessful in hydrogenating sulfur compounds to perform HDS. For the removal of sulfides, a two-phase reactor is used in which concentrated sulfuric acid oxidizes aromatic and aliphatic sulfides present in a hydrocarbon solvent, generating sulfoxides and other sulfonated species. The polar oxidized species are extracted into the acid phase, effectively desulfurizing the hydrocarbon. A reaction scheme is proposed for this

Optimization of a thermoelectric generator subsystem for high temperature PEM fuel cell exhaust heat recovery

DEFF Research Database (Denmark)

Gao, Xin; Andreasen, Søren Juhl; Kær, Søren Knudsen

2014-01-01

In previous work, a thermoelectric (TE) exhaust heat recovery subsystem for a high temperature polymer electrolyte membrane (HT-PEM) fuel cell stack was developed and modeled. Numerical simulations were conducted and have identified an optimized subsystem configuration and 4 types of compact heat...... modules are now connected into branches. The procedures of designing and optimizing this TE exhaust heat recovery subsystem are drawn out. The contribution of TE exhaust heat recovery to the HT-PEM fuel cell power system is preliminarily concluded. Its feasibility is also discussed....... exchangers with superior performance for further analysis. In this work, the on-design performances of the 4 heat exchangers are more thoroughly assessed on their corresponding optimized subsystem configurations. Afterward, their off-design performances are compared on the whole working range of the fuel...

Production of brown coal fuel dust as a high value and effective energy carrier for substituting heating oil, natural gas and black coal in the cement and metallurgical industry

Energy Technology Data Exchange (ETDEWEB)

Kubasch, A.

1985-01-01

Poduction and industrial use of brown coal dust in the German Democratic Republic are reviewed. Dust production in 14 brown coal briquetting plants increased from 818.4 kt in 1980 to 2064 kt in 1984 and will exceed 4000 kt in 1990. Quality parameters of dusts according to the TGL 15380 industrial standard are listed. The railroad car loading and shipping technology is explained with the example of modern facilities of the Schwarze Pumpe briquetting plant: dust bunkers of 200 t storage capacity, pneumatic feeding and telescope discharge systems with nitrogen gas inertization, fire prevention, and railroad car cleaning equipment, rail track heating for improved winter loading conditions, etc. Since 1979 the Deuna, Karsdorf and Bernburg cement plants have been converted to brown coal dust combustion after installation of new fuel dust shipping, storage and combustion equipment. Substitution of heating oil and gas in metallurgical blast furnaces by brown coal dust is further described. Techogical advantages of the pneumatic KOSTE fuel feeding method are enumerated.

Extension of the heat flux method to liquid (bio-)fuels

Energy Technology Data Exchange (ETDEWEB)

Meuwissen, R.

2009-01-15

The adiabatic burning velocity S{sub L} of a fuel/oxidizer mixture is a key parameter governing many properties of combustion, such as the shape and stabilization of the flame. It can be applied as an input parameter for many combustion models. Furthermore, kinetic schemes can be validated by the use of this parameter. A great extend of research has been performed on determining the adiabatic burning velocities of gaseous fuels. Liquid fuels however, have been examined far less extensive. Literature available shows eminent scatter amongst the data of independent groups and distinctive techniques. The methods used for measuring burning velocities need certain corrections for flame properties which cause additional uncertainties and make the scattering of data not completely unexpected. The heat flux burner used in this work, previously developed at the TU/e, creates a flat flame coherently no corrections for stretch are necessary. Instead, the heat exchange with the burner is considered; by measuring the temperature distribution over the burner plate, the net heat flux of the flame to the burner can be determined. By tuning the unburnt gas velocity until there is no net heat flux, the adiabatic burning velocity is found by interpolation. An extension to the original design, using a vaporized fluid in a carrier gas flow, enables to measure burning velocities of liquid fuels. In the present research, burning velocity measurements have been performed on vaporized ethanol/air flames in order to validate the setup. Similarities with the latest experimental research have been evaluated and good agreement has been found. Furthermore, temperature dependencies have been elucidated and compared to power law correlations stated by this external research. Again, good resemblance can be claimed, although the expanding of certain input parameters on mixture composition could give more solid confirmation. Subsequently, comparison with numerically performed calculations has been

Cleaning device for fuel assemblies

International Nuclear Information System (INIS)

Kita, Kaoru.

1986-01-01

Purpose: To completely remove obstacles deposited to the lower sides of supporting lattices for fuel assemblies by utilizing water within a pit before reloading of the fuel assemblies. Constitution: A cylindrical can, to which a fuel assembly is inserted through the upper end opening thereof, is vertically disposed within water of a pit and the bottom of the can is communicated with a pump by way of a suction pipe and a filter device disposed out of the pit. While on the other hand, a fuel assembly is suspended downwardly by a crane and inserted to the inside of the can through the upper end of the opening thereof and supported therein followed by starting the pump. As a result, water in the pit is circulated through the inside of the can, suction pipe, filtering device, pump, discharge pipe and to the inside of the pit thereby enabling to completely eliminate obstacles deposited to the lower surface, etc. of supporting lattices for the fuel assembly supported within the can. (Takahashi, M.)

COXPRO-II: a computer program for calculating radiation and conduction heat transfer in irradiated fuel assemblies

International Nuclear Information System (INIS)

Rhodes, C.A.

1984-12-01

This report describes the computer program COXPRO-II, which was written for performing thermal analyses of irradiated fuel assemblies in a gaseous environment with no forced cooling. The heat transfer modes within the fuel pin bundle are radiation exchange among fuel pin surfaces and conduction by the stagnant gas. The array of parallel cylindrical fuel pins may be enclosed by a metal wrapper or shroud. Heat is dissipated from the outer surface of the fuel pin assembly by radiation and convection. Both equilateral triangle and square fuel pin arrays can be analyzed. Steady-state and unsteady-state conditions are included. Temperatures predicted by the COXPRO-II code have been validated by comparing them with experimental measurements. Temperature predictions compare favorably to temperature measurements in pressurized water reactor (PWR) and liquid-metal fast breeder reactor (LMFBR) simulated, electrically heated fuel assemblies. Also, temperature comparisons are made on an actual irradiated Fast-Flux Test Facility (FFTF) LMFBR fuel assembly

Radiation heat transfer model in a spent fuel pool by TRACE code

International Nuclear Information System (INIS)

Sanchez-Saez, F.; Carlos, S.; Villanueva, J.F.; Martorell, S.

2014-01-01

Nuclear policies have experienced an important change since Fukushima Daiichi nuclear plant accident and the safety of spent fuels has been in the spot issue among all the safety concerns. The work presented consists of the thermohydraulic simulation of spent fuel pool behavior after a loss of coolant throughout transfer channel with loss of cooling transient is produced. The simulation is done with the TRACE code. One of the most important variables that define the behavior of the pool is cladding temperature, which evolution depends on the heat emission. In this work convection and radiation heat transfer is considered. When both heat transfer models are considered, a clear delay in achieving the maximum peak cladding temperature (1477 K) is observed compared with the simulation in which only convection heat transfer is considered. (authors)

First operational tests of an oxycoal hot gas cleaning facility; Erste Betriebstests einer Oxycoal-Heissgasreinigung

Energy Technology Data Exchange (ETDEWEB)

Kellermann, A.; Habermehl, M.; Foerster, M.; Kneer, R. [RWTH Aachen University (Germany). Lehrstuhl fuer Waerme- und Stoffuebertragung

2009-07-01

An oxyfuel power plant process using a ceramic high temperature membrane for oxygen supply is investigated within the scope of the OXYCOAL-AC project at RWTH Aachen Uni-versity. Implementing the membrane requires a clean gas at a temperature of 850 C. There-fore a hot gas cleaning facility based on porous ceramic candle filters is used, which is state-of-the-art for the gas cleaning of synthesis gas or for flue gas cleaning in pressurised fluid-ised bed furnaces. However, these applications operate at lower temperatures and in a sig-nificantly different atmosphere. Thus, experiences for dust removal at high temperatures in oxyfuel atmoshere are not available. Experiments with a hot gas cleaning facility were con-ducted at the experimental combustion plant of the Institute of Heat and Mass Transfer, us-ing different candle filter materials. The flue gas was provided by a coal fired 100 kW{sub th} oxy-fuel furnace. The operational behaviour of the filtration facility, the adhesion and dedusting properties of the filter cake were investigated. (orig.)

Clean Cities Now, Vol. 20, No. 1, Summer 2016 - Tackling Transportation: Clean Cities and NPS Team Up to Steer National Parks Toward a Sustainable Future.

Energy Technology Data Exchange (ETDEWEB)

2016-06-01

Clean Cities Now is the official semi-annual newsletter of Clean Cities, an initiative designed to reduce petroleum consumption in the transportation sector by advancing the use of alternative and renewable fuels, fuel economy improvements, idle-reduction measures, and new technologies, as they emerge.

Heat diffusion in cylindrical fuel elements of water cooled reactors

Energy Technology Data Exchange (ETDEWEB)

Randles, J [Technical Assessments and Services Division, Atomic Energy Establishment, Winfrith, Dorchester, Dorset (United Kingdom)

1961-09-15

This report contains a theoretical study of heat diffusion in the cylindrical fuel elements of water reactors. After setting up appropriate boundary conditions on the temperature, the steady state Fourier equation is solved both for a flat and a tilted fission power source. It is shown that source tilting does not have an appreciable effect on the peak fuel temperature while the heat flux to the coolant suffers a circumferential variation of less than a half of that of the fission power. In the last section, the theory is extended to include the effect of a flat, time dependent fission power. The time dependent Fourier equation is solved by means of a Dini series of Bessel functions which is shown to be rapidly convergent. From this series is derived expressions for the fuel element transfer functions required in reactor servo-analysis. These have the form of a rapidly convergent series of time-lag terms. (author)

Thermoacoustic sensor for nuclear fuel temperaturemonitoring and heat transfer enhancement

Energy Technology Data Exchange (ETDEWEB)

James A. Smith; Dale K. Kotter; Randall A. Alli; Steven L. Garrett

2013-05-01

A new acoustical sensing system for the nuclear power industry has been developed at The Pennsylvania State University in collaboration with Idaho National Laboratories. This sensor uses the high temperatures of nuclear fuel to convert a nuclear fuel rod into a standing-wave thermoacoustic engine. When a standing wave is generated, the sound wave within the fuel rod will be propagated, by acoustic radiation, through the cooling fluid within the reactor or spent fuel pool and can be monitored a remote location external to the reactor. The frequency of the sound can be correlated to an effective temperature of either the fuel or the surrounding coolant. We will present results for a thermoacoustic resonator built into a Nitonic-60 (stainless steel) fuel rod that requires only one passive component and no heat exchangers.

Biofuelled heating plants

International Nuclear Information System (INIS)

Gulliksson, Hans; Wennerstaal, L.; Zethraeus, B.; Johansson, Bert-Aake

2001-11-01

reference to the environmental legislation. This means, among other things, that the suggested environmental requirements should be realistic so that they can be fulfilled, but there will also be a strong motive to raise the requirements, but not so high that the new establishment of bio fuelled plants is held back in favour of old-fashioned routine technology or fossil fuels. Concurrent with the expansion of bio fuel plants in Sweden, there is an increasing need for clear and simple practical handling of this type of project in its different phases: The selection of heating system/fuel; The selection of technical solutions; Application or authorization according to environmental legislation; Design and purchasing; Inspection and performance test; Operation and control system. The selection of burning and flue gas cleaning techniques is dependent on the kind of fuel used, and the fuel's moisture content. Pellet burning furnace is the easiest and most developed solution for plants in the smaller range, and grate firing is the best solution for the bigger plants. Pulverized bio fuel burning is not used to a great extent in this particular effect range. Depending on the size and effect of the plant, the plant establishment requires authorization request according to the environmental legislation. The authorization request is different depending on the effect of the plant and the distinction between the two possible kinds is at 10 MW. The term plant size refer to the fuel supplied for all the plant's existing furnaces, which means that several plants need authorization although the effects of the individual bio fuel furnace is lower than 10 MW. An example of an EIA, which is a part of an application or authorization request, is included as an appendix. Flue gas dust cleaning is always required in this effect range. The most frequent cleaning equipment is dynamic separators, (such as multi cyclone batteries), fabric filters, (such as bag filters), and electrical partition

Database for the OECD-IAEA Paks Fuel Project

International Nuclear Information System (INIS)

Szabo, Emese; Hozer, Zoltan; Gyori, Csaba; Hegyi, Gyoergy

2010-01-01

really necessary for the analytical work. The present version of the database can be extended according to the requests of project participants and considering the availability of requested data. The present version of the database was collected by the experts of AEKI in close cooperation with Paks NPP. The work was supported by the International Atomic Energy Agency (IAEA) and the Hungarian Atomic Energy Authority (HAEA). The database has been prepared to support three types of calculations: - Thermal-hydraulic calculations to describe how the inadequate cooling conditions could have established during the incident. - Fuel behaviour simulation to describe the oxidation and degradation mechanisms of fuel assemblies. - Activity release and transport calculations to simulate the release of fission products from the failed fuel rods. The database includes the following main parts: - Design characteristics of VVER-440 fuel assemblies (main geometrical data, some mechanical properties, oxidation kinetics of Zr1%Nb cladding, and integral data of assemblies). - Operational data of damaged fuel assemblies (power histories of fuel assemblies, burnup, fuel rod internal pressure, isotope inventories, decay heat and axial power distribution). - Design characteristic of the cleaning tank (main geometrical data). - Measured data during the incident: (temperature, water level measurements, cleaning tank outlet flowrates). - Activity measurements (measured coolant activity concentrations, activity release through the chimney, flowrate of water make-up system, released activities). - Reports (describing results of investigations, chronology). - Status of fuel (results of visuals observations). The database items were collected from different sources. Some of them were calculated by Paks NPP and AEKI using VVER-440 and Paks specific input data. The details of the present version of the database including the main information on calculational work will be described in the following

Design and evaluation of aircraft heat source systems for use with high-freezing point fuels

Science.gov (United States)

Pasion, A. J.

1979-01-01

The objectives were the design, performance and economic analyses of practical aircraft fuel heating systems that would permit the use of high freezing-point fuels on long-range aircraft. Two hypothetical hydrocarbon fuels with freezing points of -29 C and -18 C were used to represent the variation from current day jet fuels. A Boeing 747-200 with JT9D-7/7A engines was used as the baseline aircraft. A 9300 Km mission was used as the mission length from which the heat requirements to maintain the fuel above its freezing point was based.

Modeling of Rocket Fuel Heating and Cooling Processes in the Interior Receptacle Space of Ground-Based Systems

Directory of Open Access Journals (Sweden)

K. I. Denisova

2016-01-01

Full Text Available The propellant to fill the fuel tanks of the spacecraft, upper stages, and space rockets on technical and ground-based launch sites before fueling should be prepared to ensure many of its parameters, including temperature, in appropriate condition. Preparation of fuel temperature is arranged through heating and cooling the rocket propellants (RP in the tanks of fueling equipment. Processes of RP temperature preparation are the most energy-intensive and timeconsuming ones, which require that a choice of sustainable technologies and modes of cooling (heating RP provided by the ground-based equipment has been made through modeling of the RP [1] temperature preparation processes at the stage of design and operation of the groundbased fueling equipment.The RP temperature preparation in the tanks of the ground-based systems can be provided through the heat-exchangers built-in the internal space and being external with respect to the tank in which antifreeze, air or liquid nitrogen may be used as the heat transfer media. The papers [1-12], which note a promising use of the liquid nitrogen to cool PR, present schematic diagrams and modeling systems for the RP temperature preparation in the fueling equipment of the ground-based systems.We consider the RP temperature preparation using heat exchangers to be placed directly in RP tanks. Feeding the liquid nitrogen into heat exchanger with the antifreeze provides the cooling mode of PR while a heated air fed there does that of heating. The paper gives the systems of equations and results of modeling the processes of RP temperature preparation, and its estimated efficiency.The systems of equations of cooling and heating RP are derived on the assumption that the heat exchange between the fuel and the antifreeze, as well as between the storage tank and the environment is quasi-stationary.The paper presents calculation results of the fuel temperature in the tank, and coolant temperature in the heat exchanger, as

Automatic Gamma-Scanning System for Measurement of Residual Heat in Spent Nuclear Fuel

International Nuclear Information System (INIS)

Osifo, Otasowie

2007-03-01

In Sweden, spent nuclear fuel will be encapsulated and placed in a deep geological repository. In this procedure, reliable and accurate spent fuel data such as discharge burnup, cooling time and residual heat must be available. The gamma scanning method was proposed in earlier work as a fast and reliable method for the experimental determination of such spent fuel data. This thesis is focused on the recent achievements in the development of a pilot gamma scanning system and its application in measuring spent fuel residual heat. The achievements include the development of dedicated spectroscopic data-acquisition and analysis software and the use of a specially designed calorimeter for calibrating the gamma scanning system. The pilot system is described, including an evaluation of the performance of the spectrum analysis software. Also described are the gamma-scanning measurements on 31 spent PWR fuel assemblies performed using the pilot system. The results obtained for the determination of residual heat are presented, showing an agreement of (2-3) % with both calorimetric and calculated data. In addition, the ability to verify declared data such as discharge burnup and cooling time is demonstrated

Gas engine driven freon-free heat supply system complying with multiple fuels (eco-energy city project)

Energy Technology Data Exchange (ETDEWEB)

Yagyu, Sumio; Maekawa, Koich; Sugawara, Koich; Hayashida, Masaru; Fujishima, Ichiro; Fukuyama, Yuji; Morikawa, Tomoyuki; Yamato, Tadao; Obata, Norio [Advanced Technology Lab., Kubota Corp., Amagasaki, Hyogo (Japan)

1999-07-01

This paper describes recent results at Kubota to develop a gas engine driven freon-free heat supply system. Utilizing a gas mixture which consists of CO and H{sub 2} supplied from a broad area energy utilization network, the system produces four heat sources (263 K, 280 K, 318 K, and 353 K) for air-conditioning, hot water supply, and refrigeration in a single system. It also conforms to fuel systems that utilize methane and hydrogen. This multi-functional heat supply system is composed of an efficient gas engine (methanol gas engine) and a freon-free heat pump (heat-assisted Stirling heat pump). The heat-assisted Stirling heat pump is mainly driven by engine shaft power and is partially assisted by thermal power provided by engine exhaust heat. By proportioning the two energy sources to match the characteristics of the driving engine, the heat pump is supplied with the maximum share of the original energy fueling the engine. Developing the system will establish freon-free thermal utilization system technology that satisfies both wide heat demands and various fuel systems. (orig.)

Co-flow anode/cathode supply heat exchanger for a solid-oxide fuel cell assembly

Science.gov (United States)

Haltiner, Jr., Karl J.; Kelly, Sean M.

2005-11-22

In a solid-oxide fuel cell assembly, a co-flow heat exchanger is provided in the flow paths of the reformate gas and the cathode air ahead of the fuel cell stack, the reformate gas being on one side of the exchanger and the cathode air being on the other. The reformate gas is at a substantially higher temperature than is desired in the stack, and the cathode gas is substantially cooler than desired. In the co-flow heat exchanger, the temperatures of the reformate and cathode streams converge to nearly the same temperature at the outlet of the exchanger. Preferably, the heat exchanger is formed within an integrated component manifold (ICM) for a solid-oxide fuel cell assembly.

Influence of fuel composition on the non-oxidizing heating of steel in a waste gas atmosphere

Energy Technology Data Exchange (ETDEWEB)

Minkler, W [LOI Industrieofenanlagen G.m.b.H., Essen (Germany, F.R.)

1979-04-01

On the basis of a number of graphs and data on theoretical combustion temperatures and the difference between the heating value of the fuel and the waste gas in respect of 1 m/sup 3/ of waste gas, the author demonstrates the influence of fuel composition on the non-oxidizing heating of steel in a waste gas atmosphere derived from five different fuels. A rotary-hearth furnace is described for the non-oxidizing heating of pressings from plain carbon and alloy steel.

Heat transfer and pressure drop of a reactor fuel element model with polyzonal spiral finning

Energy Technology Data Exchange (ETDEWEB)

Oka, S; Becirspahic, S [Institute of Nuclear Sciences Boris Kidric, Heat Transfer Department, Vinca, Beograd (Serbia and Montenegro)

1964-10-15

Heat transfer and pressure drop of a reactor fuel element model with polyzonal spiral finning have been investigated. The St-number distribution over length and perimeter of he finning are given. The mean and minimum St{sub k}-number are plotted against the Re-number. The influence of the gap between two fuel elements upon heat transfer and pressure drop, in dependence on the Re-number, and the influence of the length of the fuel element on pressure drop across the gap are shown. The influence of the relative position of the splitters of two neighboring fuel elements on pressure drop and heat transfer is shown. The investigations were performed in the Re-number range 15,000 to 100,000 (author)

COPROCESSING OF FOSSIL FUELS AND BIOMASS FOR CO2 EMISSION REDUCTION IN THE TRANSPORTATION SECTOR

Science.gov (United States)

The paper discusses an evaluation of the Hydrocarb process for conversion of carbonaceous raw material to clean carbon and methanol products. As fuel, methanol and carbon can be used economically, either independently or in slurry form, in efficient heat engines (turbines and int...

Air cleaning using regenerative silica gel wheel

DEFF Research Database (Denmark)

Fang, Lei

2011-01-01

This paper discussed the necessity of indoor air cleaning and the state of the art information on gas-phase air cleaning technology. The performance and problems of oxidation and sorption air cleaning technology were summarized and analysed based on the literature studies. Eventually, based...... on an experimental study, a technology called clean air heat pump is proposed as a practical approach for indoor air cleaning....

Clean Cities Annual Metrics Report 2008

Energy Technology Data Exchange (ETDEWEB)

Johnson, C.; Bergeron, P.

2009-09-01

This report summarizes the Department of Energy's Clean Cities coalition accomplishments in 2008, including petroleum displacement data, membership, funding, sales of alternative fuel blends, deployment of AFVs and HEVs, idle reduction initiatives, and fuel economy activities.

Heat Transfer Enhancement By Three-Dimensional Surface Roughness Technique In Nuclear Fuel Rod Bundles

Science.gov (United States)

Najeeb, Umair

This thesis experimentally investigates the enhancement of single-phase heat transfer, frictional loss and pressure drop characteristics in a Single Heater Element Loop Tester (SHELT). The heater element simulates a single fuel rod for Pressurized Nuclear reactor. In this experimental investigation, the effect of the outer surface roughness of a simulated nuclear rod bundle was studied. The outer surface of a simulated fuel rod was created with a three-dimensional (Diamond-shaped blocks) surface roughness. The angle of corrugation for each diamond was 45 degrees. The length of each side of a diamond block is 1 mm. The depth of each diamond block was 0.3 mm. The pitch of the pattern was 1.614 mm. The simulated fuel rod had an outside diameter of 9.5 mm and wall thickness of 1.5 mm and was placed in a test-section made of 38.1 mm inner diameter, wall thickness 6.35 mm aluminum pipe. The Simulated fuel rod was made of Nickel 200 and Inconel 625 materials. The fuel rod was connected to 10 KW DC power supply. The Inconel 625 material of the rod with an electrical resistance of 32.3 kO was used to generate heat inside the test-section. The heat energy dissipated from the Inconel tube due to the flow of electrical current flows into the working fluid across the rod at constant heat flux conditions. The DI water was employed as working fluid for this experimental investigation. The temperature and pressure readings for both smooth and rough regions of the fuel rod were recorded and compared later to find enhancement in heat transfer coefficient and increment in the pressure drops. Tests were conducted for Reynold's Numbers ranging from 10e4 to 10e5. Enhancement in heat transfer coefficient at all Re was recorded. The maximum heat transfer co-efficient enhancement recorded was 86% at Re = 4.18e5. It was also observed that the pressure drop and friction factor increased by 14.7% due to the increased surface roughness.

Uses of the waste heat from the interim fuel storage facility

International Nuclear Information System (INIS)

Wehrum, A.

It was the objective of this study to investigate the possibilities of a convenient use of the waste heat from the designed interim fuel storage at Ahaus. In this sense the following possibilities have been investigated: district heating, heat for industrial processes, fish-production, green house-heating, production of methane from original waste, agrotherm (agricultur field heating). It has been shown, that an economical behaviour for nearly all variations is not given without the financial help of the government, because of the high costs for heat transport and out-put. The most economical project is the intensive fish production plant. (orig.) [de

Wave heating and the U.S. magnetic fusion energy program

International Nuclear Information System (INIS)

Staten, H.S.

1985-01-01

The U.S. Government's support of the fusion program is predicated upon the long-term need for the fusion option in our energy future, as well as the near-term benefits associated with developments on the frontier of science and high technology. As a long-term energy option, magnetic fusion energy has the potential to provide an inexpensive, vast, and secure fuel reserve, to be environmentally clean and safe. It has many potential uses, which include production of central station electricity, fuel for fission reactors, synthetic fuels, and process heat for such applications as desalination of sea water. This paper presents an overview of the U.S. Government program for magnetic fusion energy. The goal and objectives of the U.S. program are reviewed followed by a summary of plasma experiments presently under way and the application of wave heating to these experiments

Fouling reduction characteristics of a no-distributor-fluidized-bed heat exchanger for flue gas heat recovery

Energy Technology Data Exchange (ETDEWEB)

Jun, Y.D.; Lee, K.B.; Islam, S.Z.; Ko, S.B. [Kongju National University, Kong Ju (Republic of Korea). Dept. for Mechanical Engineering

2008-07-01

In conventional flue gas heat recovery systems, the fouling by fly ashes and the related problems such as corrosion and cleaning are known to be major drawbacks. To overcome these problems, a single-riser no-distributor-fluidized-bed heat exchanger is devised and studied. Fouling and cleaning tests are performed for a uniquely designed fluidized bed-type heat exchanger to demonstrate the effect of particles on the fouling reduction and heat transfer enhancement. The tested heat exchanger model (1 m high and 54 mm internal diameter) is a gas-to-water type and composed of a main vertical tube and four auxiliary tubes through which particles circulate and transfer heat. Through the present study, the fouling on the heat transfer surface could successfully be simulated by controlling air-to-fuel ratios rather than introducing particles through an external feeder, which produced soft deposit layers with 1 to 1.5 mm thickness on the inside pipe wall. Flue gas temperature at the inlet of heat exchanger was maintained at 450{sup o}C at the gas volume rate of 0.738 to 0.768 CMM (0.0123 to 0.0128 m{sup 3}/sec). From the analyses of the measured data, heat transfer performances of the heat exchanger before and after fouling and with and without particles were evaluated. Results showed that soft deposits were easily removed by introducing glass bead particles, and also heat transfer performance increased two times by the particle circulation. In addition, it was found that this type of heat exchanger had high potential to recover heat of waste gases from furnaces, boilers, and incinerators effectively and to reduce fouling related problems.

Design of stationary PEFC system configurations to meet heat and power demands

Science.gov (United States)

Wallmark, Cecilia; Alvfors, Per

This paper presents heat and power efficiencies of a modeled PEFC system and the methods used to create the system configuration. The paper also includes an example of a simulated fuel cell system supplying a building in Sweden with heat and power. The main method used to create an applicable fuel cell system configuration is pinch technology. This technology is used to evaluate and design a heat exchanger network for a PEFC system working under stationary conditions, in order to find a solution with high heat utilization. The heat exchanger network in the system connecting the reformer, the burner, gas cleaning, hot-water storage and the PEFC stack will affect the heat transferred to the hot-water storage and thereby the heating of the building. The fuel, natural gas, is reformed to a hydrogen-rich gas within a slightly pressurized system. The fuel processor investigated is steam reforming, followed by high- and low-temperature shift reactors and preferential oxidation. The system is connected to the electrical grid for backup and peak demands and to a hot-water storage to meet the varying heat demand for the building. The procedure for designing the fuel cell system installation as co-generation system is described, and the system is simulated for a specific building in Sweden during 1 year. The results show that the fuel cell system in combination with a burner and hot-water storage could supply the building with the required heat without exceeding any of the given limitations. The designed co-generation system will provide the building with most of its power requirements and would further generate income by sale of electricity to the power grid.

Solution of heat removal from nuclear reactors by natural convection

Directory of Open Access Journals (Sweden)

Zitek Pavel

2014-03-01

Full Text Available This paper summarizes the basis for the solution of heat removal by natural convection from both conventional nuclear reactors and reactors with fuel flowing coolant (such as reactors with molten fluoride salts MSR.The possibility of intensification of heat removal through gas lift is focused on. It might be used in an MSR (Molten Salt Reactor for cleaning the salt mixture of degassed fission products and therefore eliminating problems with iodine pitting. Heat removal by natural convection and its intensification increases significantly the safety of nuclear reactors. Simultaneously the heat removal also solves problems with lifetime of pumps in the primary circuit of high-temperature reactors.

Fuel management at Washington State Ferries

International Nuclear Information System (INIS)

Brodeur, P.; Olds, J.

2008-01-01

This presentation discussed Washington State Ferry (WSF) operations and provided details of a biodiesel research and demonstration project. Washington has the largest ferry system in the United States, with a total of 28 vessels that operate on 10 routes through 20 terminals. Routes vary by transit times, navigational challenges, and the proximity to population centres. WSF fuel and emissions management initiatives include exhaust emission studies, clean fuel initiatives, machinery upgrades, fuel conservation initiatives, and biodiesel testing. The organization is also using waste heat recovery and a positive restraint system. The WSF biodiesel pilot program was conducted using soy-derived fuels with a purifier disk stack. The program is in agreement with recent legislation requiring that 2 per cent of annual diesel fuel sales are from biodiesel fuels, and state legislation requiring that state agencies use a minimum of 20 per cent biodiesel blends in diesel-powered vessels and vehicles. Details of project partnerships were included. tabs., figs

Heat from renewable energy. Comparison of heating systems and fuels concerning environmental aspects; Waerme aus regenerativen Energien. Heizungssysteme und Brennstoffe im oekologischen Vergleich

Energy Technology Data Exchange (ETDEWEB)

Weinberg, Jana; Stegelmeier, Marina; Kaltschmitt, Martin [TU Hamburg-Harburg (Germany). Inst. fuer Umwelttechnik und Energiewirtschaft

2013-02-01

So far, residential buildings in Germany are mainly heated with fossil fuels like heating oil and natural gas. Those fuels are burned in more or less efficient conversion plants and in doing so produce besides noteworthy amounts of greenhouse gas emissions also nitrogen oxides and particulate matter. Those emissions are not being tolerated any longer with society growing more and more environmentally-conscious. Consequently more environmentally friendly alternatives of supplying heat for residential buildings are in public discussion. For instance this is true for the use of geothermal energy, renewable fuels like biogas or wood and solar energy. Further improvement in the standard on thermal insulation of buildings to lower the absolute heating demand is discussed in parallel. To be able to evaluate these different possibilities concerning selected environmental impacts, the following work focuses on such heating options by means of life-cycle analysis. (orig.)

Hybrid Taxis Give Fuel Economy a Lift, Clean Cities, Fleet Experiences, April 2009 (Fact Sheet)

Energy Technology Data Exchange (ETDEWEB)

2009-04-01

Clean Cities helped Boston, San Antonio, and Cambridge create hybrid taxi programs. The hybrid taxis are able to achieve about twice the gas mileage of a conventional taxi while helping cut gasoline use and fuel costs. Tax credits and other incentives are helping both company owners and drivers make the switch to hybrids. Program leaders have learned some important lessons other cities can benefit from including learning a city's taxi structure, relaying benefits to drivers, and understanding the needs of owners.

REDUCING ULTRA-CLEAN TRANSPORTATION FUEL COSTS WITH HYMELT HYDROGEN

Energy Technology Data Exchange (ETDEWEB)

Donald P. Malone; William R. Renner

2003-07-31

This report describes activities for the third quarter of work performed under this agreement. Atmospheric testing was conducted as scheduled on June 5 through June 13, 2003. The test results were encouraging, however, the rate of carbon dissolution was below expectations. Additional atmospheric testing is scheduled for the first week of September 2003. Phase I of the work to be done under this agreement consists of conducting atmospheric gasification of coal using the HyMelt technology to produce separate hydrogen rich and carbon monoxide rich product stream. In addition smaller quantities of petroleum coke and a low value refinery stream will be gasified. DOE and EnviRes will evaluate the results of this work to determine the feasibility and desirability of proceeding to Phase II of the work to be done under this agreement, which is gasification of the above-mentioned feeds at a gasifier pressure of approximately 5 bar. The results of this work will be used to evaluate the technical and economic aspects of producing ultra-clean transportation fuels using the HyMelt technology in existing and proposed refinery configurations.

Improvement of Reactor Fuel Element Heat Transfer by Surface Roughness

Energy Technology Data Exchange (ETDEWEB)

Kjellstroem, B; Larsson, A E

1967-04-15

In heat exchangers with a limited surface temperature such as reactor fuel elements, rough heat transfer surfaces may give lower pumping power than smooth. To obtain data for choice of the most advantageous roughness for the superheater elements in the Marviken reactor, measurements were made of heat transfer and pressure drop in an annular channel with a smooth or rough test rod in a smooth adiabatic shroud. 24 different roughness geometries were tested. The results were transformed to rod cluster geometry by the method of W B Hall, and correlated by the friction and heat transfer similarity laws as suggested by D F Dipprey and R H Sabersky with RMS errors of 12.5 % in the friction factor and 8.1 % in the Stanton number. The relation between the Stanton number and the friction factor could be described by a relation of the type suggested by W Nunner, with a mean error of 3.1 % and an RMS error of 11.6 %. Application of the results to fuel element calculations is discussed, and the great gains in economy which can be obtained with rough surfaces are demonstrated by two examples.

Improvement of Reactor Fuel Element Heat Transfer by Surface Roughness

International Nuclear Information System (INIS)

Kjellstroem, B.; Larsson, A.E.

1967-04-01

In heat exchangers with a limited surface temperature such as reactor fuel elements, rough heat transfer surfaces may give lower pumping power than smooth. To obtain data for choice of the most advantageous roughness for the superheater elements in the Marviken reactor, measurements were made of heat transfer and pressure drop in an annular channel with a smooth or rough test rod in a smooth adiabatic shroud. 24 different roughness geometries were tested. The results were transformed to rod cluster geometry by the method of W B Hall, and correlated by the friction and heat transfer similarity laws as suggested by D F Dipprey and R H Sabersky with RMS errors of 12.5 % in the friction factor and 8.1 % in the Stanton number. The relation between the Stanton number and the friction factor could be described by a relation of the type suggested by W Nunner, with a mean error of 3.1 % and an RMS error of 11.6 %. Application of the results to fuel element calculations is discussed, and the great gains in economy which can be obtained with rough surfaces are demonstrated by two examples

Assessment of Gap Conductance Impact on Heat Split in Dual Cooled Annular Fuel

Energy Technology Data Exchange (ETDEWEB)

Chun, Kun Ho; Chun, Tae Hyun; In, Wang Kee; Yang, Yong Sik; Song, Kun Woo

2007-07-15

As a next generation fuel for PWR, a dual cooling annular fuel is being considered promisingly due to various advantage. It is able to increase the thermal margin significantly from not only large heat transfer area but also thin fuel pellet thickness. But the thermal margin at nominal condition could be degraded at certain burnup range because of the inappropriate heat split to inner and outer flow channels. A key factor to influence the heat split is the gap conductances in inner and outer clearances, which varies in terms of thermal expansion, swelling, creep, and so on in the cladding and pellet. As results of the investigation, particularly in the case of low gap conductance when the fuel rod burnup is relatively high, there is high probability that design targets might be violated. Therefore some effort is inevitable to address the concern. But, in parallel, it is necessary to more in detail investigate whether the assumed gap conductance for this analysis and the present design targets are reasonable through further reviews.

Characterizing high-temperature deformation of internally heated nuclear fuel element simulators

Energy Technology Data Exchange (ETDEWEB)

Belov, A.I.; Fong, R.W.L.; Leitch, B.W.; Nitheanandan, T.; Williams, A., E-mail: alexander.belov@cnl.ca [Canadian Nuclear Laboratories, Chalk River, Ontario (Canada)

2016-06-15

The sag behaviour of a simulated nuclear fuel element during high-temperature transients has been investigated in an experiment utilizing an internal indirect heating method. The major motivation of the experiment was to improve understanding of the dominant mechanisms underlying the element thermo-mechanical response under loss-of-coolant accident conditions and to obtain accurate experimental data to support development of 3-D computational fuel element models. The experiment was conducted using an electrically heated CANDU fuel element simulator. Three consecutive thermal cycles with peak temperatures up to ≈1000 {sup o}C were applied to the element. The element sag deflections and sheath temperatures were measured. On heating up to 600 {sup o}C, only minor lateral deflections of the element were observed. Further heating to above 700 {sup o}C resulted in an element multi-rate creep and significant permanent bow. Post-test visual and X-ray examinations revealed a pronounced necking of the sheath at the pellet-to-pellet interface locations. A wall thickness reduction was detected in the necked region that is interpreted as a sheath longitudinal strain localization effect. The sheath cross-sectioning showed signs of a 'hard' pellet-cladding interaction due to the applied cycles. A 3-D model of the experiment was generated using the ANSYS finite element code. As a fully coupled thermal mechanical simulation is computationally expensive, it was deemed sufficient to use the measured sheath temperatures as a boundary condition, and thus an uncoupled mechanical simulation only was conducted. The ANSYS simulation results match the experiment sag observations well up to the point at which the fuel element started cooling down. (author)

Waste Classification based on Waste Form Heat Generation in Advanced Nuclear Fuel Cycles Using the Fuel-Cycle Integration and Tradeoffs (FIT) Model

Energy Technology Data Exchange (ETDEWEB)

Denia Djokic; Steven J. Piet; Layne F. Pincock; Nick R. Soelberg

2013-02-01

This study explores the impact of wastes generated from potential future fuel cycles and the issues presented by classifying these under current classification criteria, and discusses the possibility of a comprehensive and consistent characteristics-based classification framework based on new waste streams created from advanced fuel cycles. A static mass flow model, Fuel-Cycle Integration and Tradeoffs (FIT), was used to calculate the composition of waste streams resulting from different nuclear fuel cycle choices. This analysis focuses on the impact of waste form heat load on waste classification practices, although classifying by metrics of radiotoxicity, mass, and volume is also possible. The value of separation of heat-generating fission products and actinides in different fuel cycles is discussed. It was shown that the benefits of reducing the short-term fission-product heat load of waste destined for geologic disposal are neglected under the current source-based radioactive waste classification system , and that it is useful to classify waste streams based on how favorable the impact of interim storage is in increasing repository capacity.

Proceedings of the 1998 oil heat technology conference

Energy Technology Data Exchange (ETDEWEB)

McDonald, R.J.

1998-04-01

The 1998 Oil Heat Technology Conference was held on April 7--8 at Brookhaven National Laboratory (BNL) under sponsorship by the US Department of Energy, Office of Building Technologies, State and Community Programs (DOE/BTS). The meeting was held in cooperation with the Petroleum Marketers Association of America (PMAA). Fourteen technical presentations was made during the two-day program, all related to oil-heat technology and equipment, these will cover a range of research, developmental, and demonstration activities being conducted within the United States and Canada, including: integrated oil heat appliance system development in Canada; a miniature heat-actuated air conditioner for distributed space conditioning; high-flow fan atomized oil burner (HFAB) development; progress in the development of self tuning oil burners; application of HFAB technology to the development of a 500 watt; thermophotovoltaic (TPV) power system; field tests of the Heat Wise Pioneer oil burner and Insight Technologies AFQI; expanded use of residential oil burners to reduce ambient ozone and particulate levels by conversion of electric heated homes to oilheat; PMAA`s Oil Heat Technician`s Manual (third edition); direct venting concept development; evolution of the chimney; combating fuel related problems; the effects of red dye and metal contamination on fuel oil stability; new standard for above ground and basement residential fuel oil storage; plastic and steel composite secondary contained tanks; and money left on the table: an economic analysis of tank cleaning.

Gravity-driven flow and heat transfer in a spent nuclear fuel storage pool

International Nuclear Information System (INIS)

Gay, R.R.

1983-01-01

The GFLOW code analyzes a three-dimensional rectangular porous medium by dividing the porous medium into a number of nodes or cells specified by the user. The finite difference form of the fluid conservation equations is solved for each node by application of a modified ''marker and cell'' numerical technique. The existence of spent nuclear fuel in any node is modeled by using a porosity value less than unity in that node and by including a surface heat transfer term in the fluid energy equation. In addition, local pressure losses due to grid spaces or other planar flow obstructions can be modeled by local loss coefficients. Heat conduction in the fuel is simulated by a fast running implicit finite difference model of the fuel, gap, and clad regions of the fuel rod

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.

Remote Robotic Cleaning System for Contaminated Hot-Cell Floor

International Nuclear Information System (INIS)

Kim, Ki Ho; Park, Jang Jin; Yang, Myung S.; Kwon, Hyo Kjo

2005-01-01

The M6 hot-cell of the Irradiated Material Examination Facility at the Korea Atomic Energy Research Institute (KAERI) has been contaminated with spent fuel debris and other radioactive waste due to the DUPIC nuclear fuel development processes. As the hot-cell is active, direct human workers' access, even with protection, to the in-cell is not possible because of the nature of the high radiation level of the spent PWR fuel. A remote robotic cleaning system has been developed for use in a highly radioactive environment of the M6 hot-cell. The remote robotic cleaning system was designed to completely eliminate human interaction with hazardous radioactive contaminants. This robotic cleaning system was also designed to remove contaminants or contaminated smears placed or fixed on the floor of the M6 hot-cell by mopping it in a remote manner. The environmental, functional and mechanical design considerations, control system and capabilities of the developed remote robotic cleaning system are presented

Clean Cities Now Vol. 17, No. 2

Energy Technology Data Exchange (ETDEWEB)

None

2013-10-23

The Fall 2013 issue of the biannual newsletter for the U.S. Department of Energy's Clean Cities initiative. The newsletter includes feature stories on deployment of alternative fuels and advanced vehicles, and articles on Clean Cities coalition successes across the country.

FUEL FORMULATION EFFECTS ON DIESEL FUEL INJECTION, COMBUSTION, EMISSIONS AND EMISSION CONTROL

Energy Technology Data Exchange (ETDEWEB)

Boehman, A; Alam, M; Song, J; Acharya, R; Szybist, J; Zello, V; Miller, K

2003-08-24

This paper describes work under a U.S. DOE sponsored Ultra Clean Fuels project entitled ''Ultra Clean Fuels from Natural Gas,'' Cooperative Agreement No. DE-FC26-01NT41098. In this study we have examined the incremental benefits of moving from low sulfur diesel fuel and ultra low sulfur diesel fuel to an ultra clean fuel, Fischer-Tropsch diesel fuel produced from natural gas. Blending with biodiesel, B100, was also considered. The impact of fuel formulation on fuel injection timing, bulk modulus of compressibility, in-cylinder combustion processes, gaseous and particulate emissions, DPF regeneration temperature and urea-SCR NOx control has been examined. The primary test engine is a 5.9L Cummins ISB, which has been instrumented for in-cylinder combustion analysis and in-cylinder visualization with an engine videoscope. A single-cylinder engine has also been used to examine in detail the impacts of fuel formulation on injection timing in a pump-line-nozzle fueling system, to assist in the interpretation of results from the ISB engine.

Evaluating the use of renewable fuel sources to heat flue-cured tobacco barns

OpenAIRE

Brown, Robert T

2018-01-01

Evaluating the use of renewable fuel sources to heat flue-cured tobacco barns Robert Taylor Brown ABSTRACT The curing of flue-cured tobacco (Nicotiana tabacum L.) is an energy intensive process and represents a significant portion of the overall cost of production. Given the goal of the industry to reduce the environmental footprint of tobacco production and the energy demand of curing, attention has been directed to explore options for the use of renewable fuels for heating to...

Blending Biodiesel in Fishing Boat Fuels for Improved Fuel Characteristics

International Nuclear Information System (INIS)

Lin, Cherng-Yuan

2014-01-01

Biodiesel is a renewable, clean, alternative energy source with advantages, such as excellent lubricity, superior biodegradability, and high combustion efficiency. Biodiesel is considered for mixing with fishing boat fuels to adjust their fuel characteristics so that toxic pollutants and greenhouse-effect gas emissions from such shipping might be reduced. The effects of blending fishing boat fuels A and B with various weight proportions of biodiesel are experimentally investigated in this study. The results show that biodiesel blending can significantly improve the inferior fuel properties of both fishing boat fuels and particularly fuel B. The flash points of both of these fuels increases significantly with the addition of biodiesel and thus enhances the safety of transporting and storing these blended fuels. The flash point of fishing boat fuel B even increases by 16% if 25 wt.% biodiesel is blended. The blending of biodiesel with no sulfur content is found to be one of the most effective ways to reduce the high sulfur content of fishing boat fuel, resulting in a reduction in the emission of sulfur oxides. The addition of only 25 wt.% biodiesel decreased the sulfur content of the fishing boat fuel by 37%. The high kinematic viscosity of fishing boat fuel B was also observed to be reduced by 63% with the blending of just 25 wt.% biodiesel. However, biodiesel blending caused a slight decrease in heating value around 1–4.5%.

Blending Biodiesel in Fishing Boat Fuels for Improved Fuel Characteristics

Energy Technology Data Exchange (ETDEWEB)

Lin, Cherng-Yuan, E-mail: lin7108@ntou.edu.tw [Department of Marine Engineering, National Taiwan Ocean University, Keelung, Taiwan (China)

2014-02-24

Biodiesel is a renewable, clean, alternative energy source with advantages, such as excellent lubricity, superior biodegradability, and high combustion efficiency. Biodiesel is considered for mixing with fishing boat fuels to adjust their fuel characteristics so that toxic pollutants and greenhouse-effect gas emissions from such shipping might be reduced. The effects of blending fishing boat fuels A and B with various weight proportions of biodiesel are experimentally investigated in this study. The results show that biodiesel blending can significantly improve the inferior fuel properties of both fishing boat fuels and particularly fuel B. The flash points of both of these fuels increases significantly with the addition of biodiesel and thus enhances the safety of transporting and storing these blended fuels. The flash point of fishing boat fuel B even increases by 16% if 25 wt.% biodiesel is blended. The blending of biodiesel with no sulfur content is found to be one of the most effective ways to reduce the high sulfur content of fishing boat fuel, resulting in a reduction in the emission of sulfur oxides. The addition of only 25 wt.% biodiesel decreased the sulfur content of the fishing boat fuel by 37%. The high kinematic viscosity of fishing boat fuel B was also observed to be reduced by 63% with the blending of just 25 wt.% biodiesel. However, biodiesel blending caused a slight decrease in heating value around 1–4.5%.

The Feasibility of Onsite Electrolysis as Primary and Clean Production Source of Fuel Hydrogen in Brazil

International Nuclear Information System (INIS)

COSTA, Andre R

2006-01-01

In accordance with the International Monetary Fund Brazil is currently the world's 12. largest and Latin America's largest economy, with a nominal GPD in the amount of US dollars 732,078 millions. Despite the fact that energy production is still heavily based on hydrocarbons, such as oil, natural gas and coal, the country is often indicated as one of the worldwide leaders in implementing renewable energy sources, primarily due to the spread utilization of bio-ethanol in transportation and the electricity production from hydropower. The purpose of this study is to assess the feasibility of onsite electrolysis as primary and clean source of fuel hydrogen in Brazil, indicating the main advantages of this production method. A perspective of the most significant challenges and actions to be taken regarding the accomplishment of a clean Brazilian hydrogen economy will be presented herein. (author)

Life Cycle Assessment of Miscanthus as a Fuel Alternative in District Heat Production

DEFF Research Database (Denmark)

Parajuli, Ranjan; Dalgaard, Tommy; Nguyen, Thu Lan Thi

2013-01-01

better than in the boilerfrom the stand point of GWP and savings in fossil fuels, but leads to a higher LU.A comparison between Miscanthus and NG shows that the former in spite of possessing advantage in reducing GWP and NRE use,additional land required for it could be seen as a disadvantage. Key words......This study assesses the environmental performance of district heat production based on Miscanthus as a fuel input and compares it with Natural Gas (NG). As a baseline scenario, we assume that the process of energy conversion from Miscanthus to heat takes place in a Combined Heat and Power (CHP...

Self-sustained cabinet based on fuel cell technology and solar energy

Energy Technology Data Exchange (ETDEWEB)

Correa, Rafael Augusto de Oliveira; Valentim, Rafael Bertier; Glir, Joao Raphael Zanlorensi; Stall, Alexandre; Sommer, Elise Meister; Sanches, Luciana Schimidilin; Dias, Fernando Gallego; Korndorfer, Heitor Medeiros de Albuquerque; Vargas, Jose Viriato Coelho [Universidade Federal do Parana (DEMEC/UFPR), Curitiba, PR (Brazil). Dept. de Engenharia Mecanica], Email: rafaelcorrea123@hotmail.com; Ordonez, Juan Carlos [Florida State University, Tallahasse, Florida (United States). Dept. of Mechanical Engineering. Center for Advanced Power Systems

2010-07-01

Along the past few years, there has been intensive research on clean and renewable energy production. Two main reasons have been pointed out: pollution caused by oil based fuels consumption and their availability diminution, which increases their production costs. Fuel Cells have shown to be a clean and renewable energy source, which reveals them as a promising solution, although their technology needs further development. Fuel Cells produce electricity, water and heat consuming hydrogen and oxygen, this provided pure or from a natural air source. Present research has combined different equipment to compose a self-sustaining fuel cells technology based cabinet for energy production, which is a Regenerative Fuel Cell System (RFC). This system contains: fuel cells stack, electrolyzer, photovoltaic panel, batteries, current inverter and a charge controller. Photovoltaic panel charges the batteries, while charge controller controls the batteries loading. Batteries are connected to an inverter which converts direct current into alternating current. Inverter is connected to an electrolyzer (Hogen GC 600) which splits the water molecule into hydrogen and oxygen molecules. Produced hydrogen supplies the fuel cell stack and the oxygen is released directly to the atmosphere. Fuel cell stacks power production is transformed into mechanical energy by a fan. Electrical power generated by Ballard stack is 5.124 W, with a voltage of 36.6 V and current of 0.14 A. The system proved to have a great efficiency and to be capable to assemble two renewable energy sources (solar and fuel cell technology) in a self-sustainable cabinet. It has also been shown that equipment such as Electrolyzer, Fuel Cell Stack and Photovoltaic panel can be fit together in the order to produce energy. Therefore, research on Fuel Cells Regenerative System reveals great importance for developing a new, clean, renewable and regenerative energy production system. (author)

Heat transfer burnout in tube-type fuel elements of nuclear power reactors

International Nuclear Information System (INIS)

Subbotin, V.; Alexeev, G.; Peskov, O.; Sapankevic, A.

1976-01-01

The conditions are formulated under which the results of the experimental research of the boilino. water heat transfer burnout carried out on models may be applied to fuel elements of nuclear reactors. Experimental material providing data on the heat transfer burnout was expanded by the results of measurements of the uneven (cosine) longitudinal distribution of heat sources. The results of the effects of helical fins or wires on heat transfer burnout are presented. (F.M.)

Heat transfer burnout in tube-type fuel elements of nuclear power reactors

Energy Technology Data Exchange (ETDEWEB)

Subbotin, V; Alexeev, G; Peskov, O; Sapankevic, A

1976-08-01

The conditions are formulated under which the results of the experimental research of the boiling. water heat transfer burnout carried out on models may be applied to fuel elements of nuclear reactors. Experimental material providing data on the heat transfer burnout was expanded by the results of measurements of the uneven (cosine) longitudinal distribution of heat sources. The results of the effects of helical fins or wires on heat transfer burnout are presented.

Clean Cities 2011 Annual Metrics Report

Energy Technology Data Exchange (ETDEWEB)

Johnson, C.

2012-12-01

This report details the petroleum savings and vehicle emissions reductions achieved by the U.S. Department of Energy's Clean Cities program in 2011. The report also details other performance metrics, including the number of stakeholders in Clean Cities coalitions, outreach activities by coalitions and national laboratories, and alternative fuel vehicles deployed.

Clean Cities 2010 Annual Metrics Report

Energy Technology Data Exchange (ETDEWEB)

Johnson, C.

2012-10-01

This report details the petroleum savings and vehicle emissions reductions achieved by the U.S. Department of Energy's Clean Cities program in 2010. The report also details other performance metrics, including the number of stakeholders in Clean Cities coalitions, outreach activities by coalitions and national laboratories, and alternative fuel vehicles deployed.

Simulation of nuclear fuel rods by using process computer-controlled power for indirect electrically heated rods

International Nuclear Information System (INIS)

Malang, S.

1975-11-01

An investigation was carried out to determine how the simulation of nuclear fuel rods with indirect electrically heated rods could be improved by use of a computer to control the electrical power during a loss-of-coolant accident (LOCA). To aid in the experiment, a new version of the HETRAP code was developed which simulates a LOCA with heater rod power controlled by a computer that adjusts rod power during a blowdown to minimize the difference in heat flux of the fuel and heater rods. Results show that without computer control of heater rod power, only the part of a blowdown up to the time when the heat transfer mode changes from nucleate boiling to transition or film boiling can be simulated well and then only for short times. With computer control, the surface heat flux and temperature of an electrically heated rod can be made nearly identical to that of a reactor fuel rod with the same cooling conditions during much of the LOCA. A small process control computer can be used to achieve close simulation of a nuclear fuel rod with an indirect electrically heated rod

Making the clean available: Escaping India’s Chulha Trap

International Nuclear Information System (INIS)

Smith, Kirk R.; Sagar, Ambuj

2014-01-01

Solid cookfuel pollution is the largest energy-related health risk globally and most important cause of ill-health for Indian women and girls. At 700 million cooking with open biomass chulhas, the Indian population exposed has not changed in several decades, in spite of hundreds of programs to make the “available clean”, i.e. to burn biomass cleanly in advanced stoves. While such efforts continue, there is need to open up another front to attack this health hazard. Gas and electric cooking, which are clean at the household, are already the choice for one-third of Indians. Needed is a new agenda to make the “clean available”, i.e., to vigorously extend these clean fuels into populations that are caught in the Chulha Trap. This will require engaging new actors including the power and petroleum ministries as well as the ministry of health, which have not to date been directly engaged in addressing this problem. It will have implications for LPG imports, distribution networks, and electric and gas user technologies, as well as setting new priorities for electrification and biofuels, but at heart needs to be addressed as a health problem, not one of energy access, if it is to be solved effectively. - Highlights: • Pollution from cooking with solid fuels is largest health hazard for Indian women and girls. • 700 million Indians are caught in a trap using solid fuels with little change in number exposed for decades. • Efforts to make the biomass fuel clean through advanced stoves have made only modest progress in decades. • A major new effort is needed to make the clean available, in the form of gas and electricity. • This will require forging new partnerships and rethinking how these fuels are currently promoted

Clean Cities Now, Vol. 18, No. 1

Energy Technology Data Exchange (ETDEWEB)

None

2014-04-30

The Spring 2014 edition of the semi-annual newsletter for the U.S. Department of Energy's Clean Cities initiative. The newsletter includes feature stories on deployment of alternative fuels and advanced vehicles, and articles on Clean Cities coalition successes across the country.

Slow heat release - solid fuel stove with acetat-trihydrate heat storage sodium; Slow heat release - Braendeovn med salthydratvarmelager

Energy Technology Data Exchange (ETDEWEB)

Zielke, U.; Bjerrum, M.; Noergaard, T. (Teknologisk Institut, Aarhus (Denmark))

2012-07-01

Of the 700,000 solid fuel stoves in Denmark, 600,000 are installed in permanent residences, and 100,000 are installed in summer cottages. Recent examinations have shown that in the heating season, these stoves contribute with a not negligible share of air pollution in the cities. The reason is often inexpedient firing and an inappropriate performance of the stove. In many cases the thermal output of the stove exceeds the heating demand of a modern residence; and the user typically reduces the stove's combustion air supply with the purpose of lowering the temperature of the accommodation space. The result is a sooting combustion followed by undesired and environmentally damaging emissions. In worst case the user fires throughout the night reducing the air to an absolutely minimum. In these situations the fuel smoulders all night, and the stove emits large amounts of undesirable and unhealthy emissions. By constructing the stove with a heat storage that can accumulate the heat from the stove and emit the heat later (when not firing), the problem with the unhealthy ''night firings'' should be eliminated. The project started with a pre-examination regarding suitable materials for a heat storage and a literature study of the subject. By using an OGC material, in this case sodiumacetat-trihydrat, the weight of the stove, in spite of the heat storage, could be held within reasonable frames, since 130 kg PCM can contain the same heat amount as 1,200 kg stone. The great challenge was to compensate for PCM's poor heat conductivities, to distribute the heat in the whole heat storage, making it melt regularly without generating local boiling. This problem was solved by construction measures. The system with sodiumacetat-trihydrat, which melts by 58 deg. C, came to function satisfactorily. 14 hours after the last firing, the temperature of the heat storage was 30 deg. C. The tests with PCM were followed by an extensive emission measuring program

Burner and dissolver off-gas treatment in HTR fuel reprocessing

International Nuclear Information System (INIS)

Barnert-Wiemer, H.; Heidendael, M.; Kirchner, H.; Merz, E.; Schroeder, G.; Vygen, H.

1979-01-01

In the reprocessing of HTR fuel, essentially all of the gaseous fission products are released during the heat-end tratment, which includes burning of the graphite matrix and dissolving of the heavy metallic residues in THOREX reagent. Three facilities for off-gas cleaning are described, the status of the facility development and test results are reported. Hot tests with a continuous dissolver for HTR-type fuel (throughput 2 kg HM/d) with a closed helium purge loop have been carried out. Preliminary results of these experiments are reported

Validation of a Waste Heat Recovery Model for a 1kW PEM Fuel Cell using Thermoelectric Generator

Science.gov (United States)

Saufi Sulaiman, M.; Mohamed, W. A. N. W.; Singh, B.; Fitrie Ghazali, M.

2017-08-01

Fuel cell is a device that generates electricity through electrochemical reaction between hydrogen and oxygen. A major by-product of the exothermic reaction is waste heat. The recovery of this waste heat has been subject to research on order to improve the overall energy utilization. However, nearly all of the studies concentrate on high temperature fuel cells using advanced thermodynamic cycles due to the high quality of waste heat. The method, characteristics and challenges in harvesting waste heat from a low temperature fuel cell using a direct energy conversion device is explored in this publication. A heat recovery system for an open cathode 1kW Proton Exchange Membrane fuel cell (PEM FC) was developed using a single unit of thermoelectric generator (TEG) attached to a heat pipe. Power output of the fuel cell was varied to obtain the performance of TEG at different stack temperatures. Natural and forced convections modes of cooling were applied to the TEG cold side. This is to simulate the conditions of a mini fuel cell vehicle at rest and in motion. The experimental results were analysed and a mathematical model based on the thermal circuit analogy was developed and compared. Forced convection mode resulted in higher temperature difference, output voltage and maximum power which are 3.3°C, 33.5 mV, and 113.96mW respectively. The heat recovery system for 1 kW Proton Exchange Membrane fuel cell (PEM FC) using single TEG was successfully established and improved the electrical production of fuel cell. Moreover, the experimental results obtained was in a good agreement with theoretical results.

Effect of heat storage and fuel price on energy management and economics of micro CCHP cogeneration systems

Energy Technology Data Exchange (ETDEWEB)

Askari, I. Baniasad [University of Zabol, Zabol (Iran, Islamic Republic of); Sadegh, M. Oukati [University of Sistan and Baluchestan, Zahedan (Iran, Islamic Republic of); Ameri, M. [Shahid Bahonar University, Kerman (Iran, Islamic Republic of)

2014-05-15

In the present work, a typical combined cooling, heating and power (CCHP) system comprised of boiler, flat solar collectors, absorption chiller and heat storage tank was investigated. The described system was considered to supply the given electricity, cooling and heating demand of a residential building; with heating and cooling needs of 100 and 50 kW, respectively. To find the optimum hybrid configurations with high reliability, low costs, low fuel consumption and emissions, a computer program was provided by authors in FORTRAN language. Different fuel prices were considered in the present work. The results indicated that the optimal operation strategy changes with Boiler and NGG fuel prices while it also changes with increasing the number of solar collectors, heat storage capacity and consequently decreasing total annual emission.

Heat recovery subsystem and overall system integration of fuel cell on-site integrated energy systems

Science.gov (United States)

Mougin, L. J.

1983-01-01

The best HVAC (heating, ventilating and air conditioning) subsystem to interface with the Engelhard fuel cell system for application in commercial buildings was determined. To accomplish this objective, the effects of several system and site specific parameters on the economic feasibility of fuel cell/HVAC systems were investigated. An energy flow diagram of a fuel cell/HVAC system is shown. The fuel cell system provides electricity for an electric water chiller and for domestic electric needs. Supplemental electricity is purchased from the utility if needed. An excess of electricity generated by the fuel cell system can be sold to the utility. The fuel cell system also provides thermal energy which can be used for absorption cooling, space heating and domestic hot water. Thermal storage can be incorporated into the system. Thermal energy is also provided by an auxiliary boiler if needed to supplement the fuel cell system output. Fuel cell/HVAC systems were analyzed with the TRACE computer program.

Heating with wood. An advisor for a correct and clean heating; Heizen mit Holz. Ein Ratgeber zum richtigen und sauberen Heizen

Energy Technology Data Exchange (ETDEWEB)

Behnke, Anja [Umweltbundesamt, Dessau (Germany); Kemper, Bernd-Michael [Landesanstalt fuer Umwelt, Messungen und Naturschutz Baden-Wuerttemberg (LUBW), Karlsruhe (Germany)

2010-02-15

Correctly used, wood is an environmental-friendly fuel. With well prepared wood, the wood furnace or wood boiler provides for comfortable warmth and does not load the environment too much. The brochure under consideration gives hints, how a wood heating is to be operated correctly.

Methodology for verification of heat transfer crisis in the nuclear fuel assemblies

International Nuclear Information System (INIS)

Sharaevsky, I. G.; Sharaevskaya, E. I.; Domashev, E. D.; Arkhypov, A. P.; Kolochko, V. N.

2003-01-01

Reliable operation of water-water type nuclear energy units and design of new generation reactors are not to be provided with wide application of best estimate ThermalHydraulic (TH) codes. It is accepted to consider that up-to-date versions of the codes are featured not only by wide range of NPPs equipment modeling and high ergonomic characteristics of realized in the codes interfaces but comprehensive substantiation of its governing component viz correlations and closure relations systems The pointed correlations and closure relations provide mathematical restraint of the main differential equations system which are necessary for adequate description of the main classes of two-phase flow TH regimes. The principal fact is that without physically justificated correlations and adequate closure relations first of all concerning heat transfer crisis at boiling (DNB) the acceptable reliability of numerical solutions cannot be guaranteed by the codes. But the significant part of realized in the codes correlations mainly on heat transfer crisis are based on the experimental data obtained more than 30 years ago for cylindrical channels. It is known that for TH reliability calculations of the WWERs core with rod fuel elements, such correlations can be applied with caution as it give significantly conservative values of critical heat flux especially at under pressure accident regimes. Moreover because of irregularity of the flow TH parameters on fuel rod elements cross-section distribution the heat transfer crisis regimes are originated only in separate 'hot' cells. Additionally it should be underlined that realized in the codes correlations and closure relations do not consider possibility occurring in the steam generating channels high frequency oscillation instability which poses a threat to the reactor safety. The high frequency oscillations can bring to the fuel elements destruction at heat fluxes much less than the critical ones. Now this type of oscillation

77 FR 72746 - Regulation of Fuels and Fuel Additives: Modifications to Renewable Fuel Standard and Diesel...

Science.gov (United States)

2012-12-06

... Fuels and Fuel Additives: Modifications to Renewable Fuel Standard and Diesel Sulfur Programs AGENCY... Fuel Standard (``RFS'') program under section 211(o) of the Clean Air Act. The direct final rule also... marine diesel fuel produced by transmix processors, and the fuel marker requirements for 500 ppm sulfur...

Auxiliary plasma heating and fueling models for use in particle simulation codes

International Nuclear Information System (INIS)

Procassini, R.J.; Cohen, B.I.

1989-01-01

Computational models of a radiofrequency (RF) heating system and neutral-beam injector are presented. These physics packages, when incorporated into a particle simulation code allow one to simulate the auxiliary heating and fueling of fusion plasmas. The RF-heating package is based upon a quasilinear diffusion equation which describes the slow evolution of the heated particle distribution. The neutral-beam injector package models the charge exchange and impact ionization processes which transfer energy and particles from the beam to the background plasma. Particle simulations of an RF-heated and a neutral-beam-heated simple-mirror plasma are presented. 8 refs., 5 figs

Fuelling clean air : municipal fuel purchasing policies that reduce emissions contributing to poor air quality and climate change

International Nuclear Information System (INIS)

Perrotta, K.

2003-03-01

Air quality can be improved by low sulphur fuels in two ways: through the direct reduction of sulphates, sulphur dioxide and PM; and by improving the effectiveness of existing emission control devices. This report examined three case studies involving the fuel purchasing policies in three Ontario municipalities: Toronto, Waterloo, and Brampton. Toronto favors purchasing conventional fuels with lower sulphur levels. Waterloo will purchase on-road diesel for its off-road diesel fleet; ultra low sulphur diesel (ULSD) for buses; and 10 per cent ethanol blended with 90 per cent gasoline (E10) for its gasoline-fuelled fleet. Brampton purchased 20 per cent biodiesel blended with 80 per cent on-road diesel (B20). Two approaches were examined for lowering emissions from gasoline fuelled vehicles: favouring gasoline with the lowest sulphur levels, and purchasing E10. It was recommended that the Greater Toronto Area (GTA) Clean Air Council look into: ownership of emissions trading credits created as a result of fuel purchasing policies; the benefits of, and mechanisms available for, pooling fuel purchases; and, establishing a subcommittee to monitor developments related to fuels, vehicles and emission control technologies. 48 refs., 18 tabs

Combined heat and power with the use of fuel cells; Kraft-Waerme-Kopplung mit Brennstoffzellen

Energy Technology Data Exchange (ETDEWEB)

Arends, G; Lehmann, M [Deutsches Brennstoffzellenforum e.V., Bonn (Germany)

1997-12-01

Fuel cell systems have the potential to cause increased efficiency, cleanness and decentralization in all areas of energy consumption. This article describes technical characteristics and current development status of the different fuel cell types with a view to their use as cogeneration facilities. The following types of fuel cell are examined: - Proton Exchange Membrane Fuel Cell (PEMFC), - Phosphoric Acid Fuel Cell (PAFC), - Molten Carbonate Fuel Cell (MCFC), - Solid Oxide Fuel Cell (SOFC). (orig.) [Deutsch] Brennstoffzellensysteme haben das Potential, in allen Sektoren des Endenergieverbrauchs wesentliche Verbesserungen bezueglich Effizienz, Sauberkeit und Dezentralisierung zu bewirken. In dem folgenden Aufsatz werden die technischen Eigenschaften und der aktuelle Entwicklungsstand verschiedener Brennstoffzellentypen im Hinblick auf ihren Einsatz in der Kraft-Waerme-Kopplung beschrieben. Ein Ueberblick ueber neueste Demonstrationsprojekte informiert ueber den Stand der Technik. Konkrete - wenngleich unsichere - Angaben zur Wirtschaftlichkeit projektierter Brennstoffzellensystme ergeben, dass die genannten Vorteile der Brennstoffzellentechnologie moeglicherweise schon um die Jahrhundertwende auch oekonomisch interessant werden. (orig.)

Direct synthesis of Pt-free catalyst on gas diffusion layer of fuel cell and usage of high boiling point fuels for efficient utilization of waste heat

International Nuclear Information System (INIS)

Nandan, Ravi; Goswami, Gopal Krishna; Nanda, Karuna Kar

2017-01-01

Graphical abstract: Direct-grown boron-doped carbon nanotubes on gas-diffusion layer as efficient Pt-free cathode catalyst for alcohol fuel cells, high boiling point fuels used to obtain hot fuels for the enhancement of cell performance that paves the way for the utilization of waste heat. Display Omitted -- Highlights: •One-step direct synthesis of boron-doped carbon nanotubes (BCNTs) on gas diffusion layer (GDL). •Home built fuel-cell testing using BCNTs on GDL as Pt-free cathode catalyst. •BCNTs exhibit concentration dependent oxygen reduction reaction and the cell performance. •Effective utilization of waste heat to raise the fuel temperature. •Fuel selectivity to raise the fuel temperature and the overall performance of the fuel cells. -- Abstract: Gas diffusion layers (GDL) and electrocatalysts are integral parts of fuel cells. It is, however, a challenging task to grow Pt-free robust electrocatalyst directly on GDL for oxygen reduction reaction (ORR) – a key reaction in fuel cells. Here, we demonstrate that boron-doped carbon nanotubes (BCNTs) grown directly on gas-diffusion layer (which avoid the need of ionomer solution used for catalyst loading) can be used as efficient Pt-free catalyst in alcohol fuel cells. Increase in boron concentration improves the electrochemical ORR activity in terms of onset and ORR peak positions, half-wave potentials and diffusion-limited current density that ensure the optimization of the device performance. The preferential 4e − pathway, excellent cell performance, superior tolerance to fuel crossover and long-term stability makes directly grown BCNTs as an efficient Pt-free cathode catalyst for cost-effective fuel cells. The maximum power density of the fuel cell is found to increase monotonically with boron concentration. In addition to the application of BCNTs in fuel cell, we have introduced the concept of hot fuels so that waste heat can effectively be used and external power sources can be avoided. The fuel

Alternative Fuels Data Center: Alternative Fuel Vehicles Beat the Heat,

Science.gov (United States)

was the networking assistance they got from the local Clean Cities coalition. "Valley of the Sun ." For more natural gas maintenance and safety information, contact your local Clean Cities Clean Cities brought us together with other fleets and industry experts and proved highly instrumental

About calculation results of heat transfer in the fuel assembly clusters cooled by water with supercritical parameters

International Nuclear Information System (INIS)

Grabezhnaya, V.A.

2008-01-01

Paper reviews the numerical investigation into the heat transfer in the supercritical water cooled fuel assemblies on the basis of the various commercial codes. The turbulence available models specified in the codes describe adequately the experimental data in tubes within the range of flow temperatures away from the pseudocritical point, as well as under high mass velocities. There are k-ε type turbulence models that show qualitatively the local acceleration (slowdown) of the heat transfer in tubes, but they fail to describe the mentioned phenomena quantitatively. To determine the effect of grid spacers on the suppression of the heat transfer local slowdown and on the heat transfer acceleration in fuel assemblies and to ensure more accurate calculation of the fuel element cladding maximum temperature one should perform a number of the experiments making use of the fuel assembly models [ru

Heat recovery properties from fuel cell system for telecommunications use; Tsushin`yo nenryo denchi system ni okeru hainetsu kaishu tokusei

Energy Technology Data Exchange (ETDEWEB)

Ishizawa, M.; Iida, S.; Abe, I.; Yamamoto, M. [NTT Integrated Information and Energy Systems Laboratories, Tokyo (Japan)

1997-08-20

NTT is developing a phosphoric-acid fuel-cell energy system for telecommunication co-generation systems to reduce energy costs and help preserve the environment. Fuel cells are used to provide electrical power to telecommunication equipment and the heat energy that is generated is used by the absorption refrigerators to cool the telecommunication rooms throughout the year. We field-tested this fuel-cell energy system in a telephone office. Two heat recovery methods were applied in the test: one uses direct steam heat recovery from fuel-cell stack coolant to keep the heat recovery temperature high and to avoid requiring a heat exchanger for the recovery; the other uses heat recovery from the reformer exhaust gas that is directly in contact with the heat recovery water to recover heat more economically. Our field tests confirmed that the average efficiency of heat recovery from fuel-cell stack coolant is 16%, and from the reformer exhaust gas is 9% under 80-kW continuous operation. Maximum total efficiency including electrical power efficiency was confirmed to be about 73% under the condition of 100-kW and an S/C ratio of 2.5 in the winter period: heat recovery from the fuel-cell stack coolant was 23%, from the reformer exhaust gas was 10%, and from electrical conversion was about 40%. 9 refs., 12 figs., 1 tab.

Heat transfer coefficient for lead matrixing in disposal containers for used reactor fuel

International Nuclear Information System (INIS)

Mathew, P.M.; Taylor, M.; Krueger, P.A.

1985-02-01

In the Canadian Nuclear Fuel Waste Management Program, metal matrices with low melting points are being evaluated for their potential to provide support for the shell of disposal containers for used fuel, and to act as an additional barrier to the release of radionuclides. The metal matrix would be incorporated into the container by casting. To study the heat transfer processes during solidification, a steady-state technique was used, involving lead as the cast metal, to determine the overall heat transfer coefficient between the lead and some of the candidate container materials. The existence of an air gap between the cast lead and the container material appeared to control the overall heat transfer coefficient. The experimental observations indicated that the surface topography of the container material influences the heat transfer and that a smoother surface results in a greater heat transfer than a rough surface. The experimental results also showed an increasing heat transfer coefficient with increasing temperature difference across the container base plates; a model developed to base-plate bending can explain the observed results

Alternative Solvents and Technologies for Precision Cleaning of Aerospace Components

Science.gov (United States)

Grandelli, Heather; Maloney, Phillip; DeVor, Robert; Hintze, Paul

2014-01-01

Precision cleaning solvents for aerospace components and oxygen fuel systems, including currently used Vertrel-MCA, have a negative environmental legacy, high global warming potential, and have polluted cleaning sites. Thus, alternative solvents and technologies are being investigated with the aim of achieving precision contamination levels of less than 1 mg/sq ft. The technologies being evaluated are ultrasonic bath cleaning, plasma cleaning and supercritical carbon dioxide cleaning.

Bioremediation Potential of Terrestrial Fuel Spills †

OpenAIRE

Song, Hong-Gyu; Wang, Xiaoping; Bartha, Richard

1990-01-01

A bioremediation treatment that consisted of liming, fertilization, and tilling was evaluated on the laboratory scale for its effectiveness in cleaning up a sand, a loam, and a clay loam contaminated at 50 to 135 mg g of soil−1 by gasoline, jet fuel, heating oil, diesel oil, or bunker C. Experimental variables included incubation temperatures of 17, 27, and 37°C; no treatment; bioremediation treatment; and poisoned evaporation controls. Hydrocarbon residues were determined by quantitative gas...

Association of Solid Fuel Use With Risk of Cardiovascular and All-Cause Mortality in Rural China.

Science.gov (United States)

Yu, Kuai; Qiu, Gaokun; Chan, Ka-Hung; Lam, Kin-Bong Hubert; Kurmi, Om P; Bennett, Derrick A; Yu, Canqing; Pan, An; Lv, Jun; Guo, Yu; Bian, Zheng; Yang, Ling; Chen, Yiping; Hu, Frank B; Chen, Zhengming; Li, Liming; Wu, Tangchun

2018-04-03

When combusted indoors, solid fuels generate a large amount of pollutants such as fine particulate matter. To assess the associations of solid fuel use for cooking and heating with cardiovascular and all-cause mortality. This nationwide prospective cohort study recruited participants from 5 rural areas across China between June 2004 and July 2008; mortality follow-up was until January 1, 2014. A total of 271 217 adults without a self-reported history of physician-diagnosed cardiovascular disease at baseline were included, with a random subset (n = 10 892) participating in a resurvey after a mean interval of 2.7 years. Self-reported primary cooking and heating fuels (solid: coal, wood, or charcoal; clean: gas, electricity, or central heating), switching of fuel type before baseline, and use of ventilated cookstoves. Death from cardiovascular and all causes, collected through established death registries. Among the 271 217 participants, the mean (SD) age was 51.0 (10.2) years, and 59% (n = 158 914) were women. A total of 66% (n = 179 952) of the participants reported regular cooking (at least weekly) and 60% (n = 163 882) reported winter heating, of whom 84% (n = 150 992) and 90% (n = 147 272) used solid fuels, respectively. There were 15 468 deaths, including 5519 from cardiovascular causes, documented during a mean (SD) of 7.2 (1.4) years of follow-up. Use of solid fuels for cooking was associated with greater risk of cardiovascular mortality (absolute rate difference [ARD] per 100 000 person-years, 135 [95% CI, 77-193]; hazard ratio [HR], 1.20 [95% CI, 1.02-1.41]) and all-cause mortality (ARD, 338 [95% CI, 249-427]; HR, 1.11 [95% CI, 1.03-1.20]). Use of solid fuels for heating was also associated with greater risk of cardiovascular mortality (ARD, 175 [95% CI, 118-231]; HR, 1.29 [95% CI, 1.06-1.55]) and all-cause mortality (ARD, 392 [95% CI, 297-487]; HR, 1.14 [95% CI, 1.03-1.26]). Compared with persistent solid fuel

A prediction method of the effect of radial heat flux distribution on critical heat flux in CANDU fuel bundles

International Nuclear Information System (INIS)

Yuan, Lan Qin; Yang, Jun; Harrison, Noel

2014-01-01

Fuel irradiation experiments to study fuel behaviors have been performed in the experimental loops of the National Research Universal (NRU) Reactor at Atomic Energy of Canada Limited (AECL) Chalk River Laboratories (CRL) in support of the development of new fuel technologies. Before initiating a fuel irradiation experiment, the experimental proposal must be approved to ensure that the test fuel strings put into the NRU loops meet safety margin requirements in critical heat flux (CHF). The fuel strings in irradiation experiments can have varying degrees of fuel enrichment and burnup, resulting in large variations in radial heat flux distribution (RFD). CHF experiments performed in Freon flow at CRL for full-scale bundle strings with a number of RFDs showed a strong effect of RFD on CHF. A prediction method was derived based on experimental CHF data to account for the RFD effect on CHF. It provides good CHF predictions for various RFDs as compared to the data. However, the range of the tested RFDs in the CHF experiments is not as wide as that required in the fuel irradiation experiments. The applicability of the prediction method needs to be examined for the RFDs beyond the range tested by the CHF experiments. The Canadian subchannel code ASSERT-PV was employed to simulate the CHF behavior for RFDs that would be encountered in fuel irradiation experiments. The CHF predictions using the derived method were compared with the ASSERT simulations. It was observed that the CHF predictions agree well with the ASSERT simulations in terms of CHF, confirming the applicability of the prediction method in fuel irradiation experiments. (author)

Heat transfer analysis of the geologic disposal of spent fuel and high-level waste storage canisters

International Nuclear Information System (INIS)

Allen, G.K.

1980-08-01

Near-field temperatures resulting from the storage of high-level waste canisters and spent unreprocessed fuel assembly canisters in geologic formations were determined. Preliminary design of the repository was modeled for a heat transfer computer code, HEATING5, which used the Crank-Nicolson finite difference method to evaluate transient heat transfer. The heat transfer system was evaluated with several two- and three-dimensional models which transfer heat by a combination of conduction, natural convention, and radiation. Physical properties of the materials in the model were based upon experimental values for the various geologic formations. The effects of canister spacing, fuel age, and use of an overpack were studied for the analysis of the spent fuel canisters; salt, granite, and basalt were considered as the storage media for spent fuel canisters. The effects of canister diameter and use of an overpack were studied for the analysis of the high-level waste canisters; salt was considered as the only storage media for high-level waste canisters. Results of the studies on spent fuel assembly canisters showed that the canisters could be stored in salt formations with a maximum heat loading of 134 kw/acre without exceeding the temperature limits set for salt stability. The use of an overpack had little effect on the peak canister temperatures. When the total heat load per acre decreased, the peak temperatures reached in the geologic formations decreased; however, the time to reach the peak temperatures increased. Results of the studies on high-level waste canisters showed that an increased canister diameter will increase the canister interior temperatures considerably; at a constant areal heat loading, a 381 mm diameter canister reached almost a 50 0 C higher temperature than a 305 mm diameter canister. An overpacked canister caused almost a 30 0 C temperature rise in either case

Removal of sulphur-containing odorants from fuel gases for fuel cell-based combined heat and power applications

Energy Technology Data Exchange (ETDEWEB)

De Wild, P.J.; Nyqvist, R.G.; De Bruijn, F.A.; Stobbe, E.R. [ECN Hydrogen and Clean Fossil Fuels, Petten (Netherlands)

2006-02-15

Natural gas (NG) and liquefied petroleum gas (LPG) are important potential feedstocks for the production of hydrogen for fuel cell-based (e.g. proton exchange membrane fuel cells (PEMFC)) or solid oxide fuel Cells (SOFC) combined heat and power (CHP) applications. To prevent detrimental effects on the (electro)catalysts in fuel cell-based combined heat and power installations (FC-CHP), sulphur removal from the feedstock is mandatory. An experimental bench-marking study of adsorbents has identified several candidates for the removal of sulphur containing odorants at low temperature. Among these adsorbents a new material has been discovered that offers an economically attractive means to remove TetraHydroThiophene (THT), the main European odorant, from natural gas at ambient temperature. The material is environmentally benign, easy to use and possesses good activity (residual sulphur levels below 20 ppbv) and capacity for the common odorant THT in natural gas. When compared to state-of-the-art metal-promoted active carbon the new material has a THT uptake capacity that is up to 10 times larger, depending on temperature and pressure. Promoted versions of the new material have shown potential for the removal of THT at higher temperatures and/or for the removal of other odorants such as mercaptans from natural gas or from LPG.

Removal of sulphur-containing odorants from fuel gases for fuel cell-based combined heat and power applications

Energy Technology Data Exchange (ETDEWEB)

de Wild, P.J.; Nyqvist, R.G.; de Bruijn, F.A.; Stobbe, E.R. [Energy Research Centre of The Netherlands ECN, P.O. Box 1, 1755 ZG Petten (Netherlands)

2006-09-22

Natural gas (NG) and liquefied petroleum gas (LPG) are important potential feedstocks for the production of hydrogen for fuel cell-based (e.g. proton exchange membrane fuel cells (PEMFC) or solid oxide fuel Cells (SOFC) combined heat and power (CHP) applications. To prevent detrimental effects on the (electro)catalysts in fuel cell-based combined heat and power installations (FC-CHP), sulphur removal from the feedstock is mandatory. An experimental bench-marking study of adsorbents has identified several candidates for the removal of sulphur containing odorants at low temperature. Among these adsorbents a new material has been discovered that offers an economically attractive means to remove TetraHydroThiophene (THT), the main European odorant, from natural gas at ambient temperature. The material is environmentally benign, easy to use and possesses good activity (residual sulphur levels below 20ppbv) and capacity for the common odorant THT in natural gas. When compared to state-of-the-art metal-promoted active carbon the new material has a THT uptake capacity that is up to 10 times larger, depending on temperature and pressure. Promoted versions of the new material have shown potential for the removal of THT at higher temperatures and/or for the removal of other odorants such as mercaptans from natural gas or from LPG. (author)

Allocation of fossil and nuclear fuels. Heat production from chemically and physically bound energy

International Nuclear Information System (INIS)

Wagner, U.

2008-01-01

The first part of the book presents the broad field of allocation, transformation, transport and distribution of the most important energy carriers in the modern power industry. The following chapters cover solid fossil fuel, liquid fuel, gaseous fuel and nuclear fuel. The final chapters concern the heat production from chemically and physically bound energy, including elementary analysis, combustion calculations, energy balance considerations in fossil fuel fired systems, and fundamentals of nuclear physics

Experimental investigation on combustion and heat transfer characteristics in a furnace fueled with unconventional biomass fuels (date stones and palm stalks)

International Nuclear Information System (INIS)

Al-Omari, S.-A.B.

2006-01-01

The combustion of date stones and palm stalks in a small scale furnace with a conical solid fuel bed is investigated experimentally. This investigation (to the best of the knowledge of the author) is the first addressing date stones as a new renewable energy source. Different experimental conditions are investigated where different fuel feed conditions and different combustion air flow rates are considered. The major results are given in terms of the fuel reduction rates and the heat transferred to the cooling water flowing in a water jacket around the furnace as functions of time. Combustion of the biomass fuels considered here in the investigated furnace is initiated by using LPG fuel as a starter. The hot products of LPG combustion, which is taking place in a burner built prior to the investigated solid fuel furnace, are allowed to penetrate the conical fuel bed for 2-3 min from its bottom base in the upward direction, causing effective heating and gasification and pyrolysis of the solid fuel in the bed to take place. The resulting combustible gases mix with the combustion air and subsequently are ignited by an external ignition source. The results of the present study highlight date stones as a renewable energy source with a good potential

State heating oil and propane program. Final report, 1996--1997

International Nuclear Information System (INIS)

Hunton, G.

1997-01-01

The following is a summary report of the New Hampshire Governor's Office of Energy and Community Services (ECS) participation in the State Heating Oil and Propane Program (SHOPP) for the 1996-97 heating season. SHOPP is a cooperative effort, linking energy offices in East Coast and Midwest states, with the Department of Energy (DOE), Energy Information Administration (EIA) for the purpose of collecting retail price data for heating oil and propane. The program funded by the participating state with a matching grant from DOE. SHOPP was initiated in response to congressional inquires into supply difficulties and price spikes of heating oil and propane associated with the winter of 1989/90. This is important to New Hampshire because heating oil controls over 55% of the residential heating market statewide. Propane controls 10% of the heating market statewide and is widely used in rural areas where Natural GAs is not available. Lower installation cost, convenience, lower operating costs compared to electricity and its perception as a clean heating fuel has increased the popularity of propane in New Hampshire and should continue to do so in the future. Any disruption in supply of these heating fuels to New Hampshire could cause prices to skyrocket and leave many residents in the cold

METHODOLOGY FOR DETERMINING THE OPTIMAL CLEANING PERIOD OF HEAT EXCHANGERS BY USING THE CRITERIA OF MINIMUM COST

Directory of Open Access Journals (Sweden)

Yanileisy Rodríguez Calderón

2015-04-01

Full Text Available One of the most serious problems of the Process Industry is that when planning the maintenance of the heat exchangers is not applied the methodologies based on economic criteria to optimize periods of cleaning surfaces resulting in additional costs for the company and for the country. This work develops and proposes a methodical based on the criterion of Minimum Cost for determining the optimal cleaning period. It is given an example of application of this method to the case of intercoolers of a centrifugal compressor with a high fouling level.It occurs this because is used sea water with many microorganisms as cooling agent which severely embeds transfer surfaces of side water. The methodology employed can be generalized to other applications.

Free automotive and heating fuels for home and farm

International Nuclear Information System (INIS)

Murray, K.

1991-01-01

This book is for farmers or any landowners with access to free materials, such as agricultural wastes, that can be converted with minimum expense to heating fuel of to ethanol for automotive use. Farmers can learn how to make and use stoves, furnaces or stills for processing their own free materials for their own use or their neighbors. If one is a good mechanic one can learn how to adjust carburetors, to start a business converting engines to burn ethanol. The book is intended to provide the information you need to make practical use of waste materials and to save money. The book contains five chapters: Ethanol feedstocks; Crops for burning; Conversion to fuel; Fuel Utilization; and Business Opportunities. These chapters have been processed separately for inclusion on the data base

Applying Physics to Clean Energy Needs

Science.gov (United States)

Environmental Science and Technology, 1975

1975-01-01

Solar and ocean thermal energy sources offer real potential for an environmentally clean fuel by the year 2000. A review of current research contracts relating to ocean-thermal energy, cost requirements of plant construction and uses of the electricity produced, such as synthesizing ammonia and synthetic fuels, are discussed. (BT)

Clean Air for London (CLEARFLO) Final Campaign Summary

Energy Technology Data Exchange (ETDEWEB)

Worsnop, D. R. [Aerodyne Research, Inc., Billerica, MA (United States); Williams, L. R. [Aerodyne Research, Inc., Billerica, MA (United States); Herndon, S. C. [Aerodyne Research, Inc., Billerica, MA (United States); Dubey, M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Ng, N. L. [Georgia Inst. of Technology, Atlanta, GA (United States); Thornton, J. [Univ. of Washington, Seattle, WA (United States); Knighton, B. [Montana State Univ., Bozeman, MT (United States); Coulter, R. [Argonne National Lab. (ANL), Argonne, IL (United States); Prévôt, Ash [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

2016-03-01

This field campaign funded the participation of scientists from seven different research groups and operated over thirty instruments during the Winter Intensive Operating Period (January-February 2012) of the Clean Air for London (ClearfLo) campaign. The campaign took place at a rural site in Detling, UK, 45 kilometers southeast of central London. The primary science questions for the ClearfLo winter IOP (intensive operational periods) were: 1) “what is the urban increment of particulate matter (PM) and other pollutants in the greater London area?” and 2) “what is the contribution of solid fuel use for home heating to wintertime PM?” An additional motivation for the Detling measurements was the question of whether coatings on black carbon particles enhance absorption.

CFD Simulation of Heat and Fluid Flow for Spent Fuel in a Dry Storage

International Nuclear Information System (INIS)

In, Wangkee; Kwack, Youngkyun; Kook, Donghak; Koo, Yanghyun

2014-01-01

A dry storage system is used for the interim storage of spent fuel prior to permanent depository and/or recycling. The spent fuel is initially stored in a water pool for more than 5 years at least after dispatch from the reactor core and is transported to dry storage. The dry cask contains a multiple number of spent fuel assemblies, which are cooled down in the spent fuel pool. The dry cask is usually filled up with helium gas for increasing the heat transfer to the environment outside the cask. The dry storage system has been used for more than a decade in United States of America (USA) and the European Union (EU). Korea is also developing a dry storage system since its spent fuel pool is anticipated to be full within 10 years. The spent fuel will be stored in a dry cask for more than 40 years. The integrity and safety of spent fuel are important for long-term dry storage. The long-term storage will experience the degradation of spent fuel such as the embrittlement of fuel cladding, thermal creep and hydride reorientation. High burn-up fuel may expedite the material degradation. It is known that the cladding temperature has a strong influence on the material degradation. Hence, it is necessary to accurately predict the local distribution of the cladding temperature using the Computational Fluid Dynamics (CFD) approach. The objective of this study is to apply the CFD method for predicting the three-dimensional distribution of fuel temperature in a dry cask. This CFD study simulated the dry cask for containing the 21 fuel assemblies under development in Korea. This paper presents the fluid velocity and temperature distribution as well as the fuel temperature. A two-step CFD approach was applied to simulate the heat and fluid flow in a dry storage of 21 spent fuel assemblies. The first CFD analysis predicted the helium flow and temperature in a dry cask by a assuming porous body of the spent fuel. The second CFD analysis was to simulate a spent fuel assembly in the

Clean Cities Now Vol. 19, No. 1

Energy Technology Data Exchange (ETDEWEB)

None

2015-07-24

Now is the official bi-annual newsletter of Clean Cities, an initiative designed to reduce petroleum consumption in the transportation sector by advancing the use of alternative and renewable fuels, fuel economy improvements, idle-reduction measures, and new technologies, as they emerge.

Impact of thermodynamic properties and heat loss on ignition of transportation fuels in rapid compression machines

KAUST Repository

Ahmed, Ahfaz

2018-01-30

Rapid compression machines (RCM) are extensively used to study autoignition of a wide variety of fuels at engine relevant conditions. Fuels ranging from pure species to full boiling range gasoline and diesel can be studied in an RCM to develop a better understanding of autoignition kinetics in low to intermediate temperature ranges. In an RCM, autoignition is achieved by compressing a fuel/oxidizer mixture to higher pressure and temperature, thereby initiating chemical reactions promoting ignition. During these experiments, the pressure is continuously monitored and is used to deduce significant events such as the end of compression and the onset of ignition. The pressure profile is also used to assess the temperature evolution of the gas mixture with time using the adiabatic core hypothesis and the heat capacity ratio of the gas mixture. In such RCM studies, real transportation fuels containing many components are often represented by simpler surrogate fuels. While simpler surrogates such as primary reference fuels (PRFs) and ternary primary reference fuel (TPRFs) can match research and motor octane number of transportation fuels, they may not accurately replicate thermodynamic properties (including heat capacity ratio). This non-conformity could exhibit significant discrepancies in the end of compression temperature, thereby affecting ignition delay (τign) measurements. Another aspect of RCMs that can affect τign measurement is post compression heat loss, which depends on various RCM parameters including geometry, extent of insulation, pre-heating temperature etc. To, better understand the effects of these non-chemical kinetic parameters on τign, thermodynamic properties of a number of FACE G gasoline surrogates were calculated and simulated in a multi-zone RCM model. The problem was further investigated using a variance based analysis and individual sensitivities were calculated. This study highlights the effects on τign due to thermodynamic properties of

Impact of thermodynamic properties and heat loss on ignition of transportation fuels in rapid compression machines

KAUST Repository

Ahmed, Ahfaz; Hantouche, Mireille; Khurshid, Muneeb; Mohamed, Samah; Nasir, Ehson Fawad; Farooq, Aamir; Roberts, William L.; Knio, Omar; Sarathy, Mani

2018-01-01

Rapid compression machines (RCM) are extensively used to study autoignition of a wide variety of fuels at engine relevant conditions. Fuels ranging from pure species to full boiling range gasoline and diesel can be studied in an RCM to develop a better understanding of autoignition kinetics in low to intermediate temperature ranges. In an RCM, autoignition is achieved by compressing a fuel/oxidizer mixture to higher pressure and temperature, thereby initiating chemical reactions promoting ignition. During these experiments, the pressure is continuously monitored and is used to deduce significant events such as the end of compression and the onset of ignition. The pressure profile is also used to assess the temperature evolution of the gas mixture with time using the adiabatic core hypothesis and the heat capacity ratio of the gas mixture. In such RCM studies, real transportation fuels containing many components are often represented by simpler surrogate fuels. While simpler surrogates such as primary reference fuels (PRFs) and ternary primary reference fuel (TPRFs) can match research and motor octane number of transportation fuels, they may not accurately replicate thermodynamic properties (including heat capacity ratio). This non-conformity could exhibit significant discrepancies in the end of compression temperature, thereby affecting ignition delay (τign) measurements. Another aspect of RCMs that can affect τign measurement is post compression heat loss, which depends on various RCM parameters including geometry, extent of insulation, pre-heating temperature etc. To, better understand the effects of these non-chemical kinetic parameters on τign, thermodynamic properties of a number of FACE G gasoline surrogates were calculated and simulated in a multi-zone RCM model. The problem was further investigated using a variance based analysis and individual sensitivities were calculated. This study highlights the effects on τign due to thermodynamic properties of

Enhancement of heat transfer in HPLWR fuel assemblies

International Nuclear Information System (INIS)

Bastron, A.; Hofmeister, J.; Meyer, L.; Schulenberg, T.

2005-01-01

A study on different methods for enhancement of heat transfer in fuel assemblies for a High Performance Light Water Reactor has been performed to indicate the potential for a further increase of core outlet temperature at given cladding temperatures, or for reduction of peak cladding temperatures at the envisaged core outlet temperature. As a result, the introduction of an artificial surface roughness or the use of a staircase type grid spacer should increase the heat transfer coefficient of the coolant at the cladding surface by more than a factor of two, which will reduce the peak cladding temperature by at least 50 degC. The paper provides further details for realization of these measures. (author)

Sociology: Clean-energy conservatism

Science.gov (United States)

McCright, Aaron M.

2017-03-01

US conservatives receive a steady stream of anti-environmental messaging from Republican politicians. However, clean-energy conservatives sending strong counter-messages on energy issues could mobilize moderate conservatives to break away from the dominant right-wing defence of fossil fuels.

Combined Heat and Power (CHP) as a Compliance Option under the Clean Power Plan: A Template and Policy Options for State Regulators

Energy Technology Data Exchange (ETDEWEB)

None

2015-07-30

Combined Heat and Power (CHP) is an important option for states to consider in developing strategies to meet their emission targets under the US Environmental Protection Agency's Clean Power Plan. This Template is designed to highlight key issues that states should consider when evaluating whether CHP could be a meaningful component of their compliance plans. It demonstrates that CHP can be a valuable approach for reducing emissions and helping states achieve their targets. While the report does not endorse any particular approach for any state, and actual plans will vary dependent upon state-specific factors and determinations, it provides tools and resources that states can use to begin the process, and underscores the opportunity CHP represents for many states. . By producing both heat and electricity from a single fuel source, CHP offers significant energy savings and carbon emissions benefits over the separate generation of heat and power, with a typical unit producing electricity with half the emissions of conventional generation. These efficiency gains translate to economic savings and enhanced competitiveness for CHP hosts, and emissions reductions for the state, along with helping to lower electric bills; and creating jobs in the design, construction, installation and maintenance of equipment. In 2015, CHP represents 8 percent of electric capacity in the United States and provides 12 percent of total power generation. Projects already exist in all 50 states, but significant technical and economic potential remains. CHP offers a tested way for states to achieve their emission limits while advancing a host of ancillary benefits.

Problems of heat transfer within the containing vessel of high performance LMFBR spent fuel shipping casks

International Nuclear Information System (INIS)

Pope, R.B.; Gartling, D.K.; Schimmel, W.P. Jr.; Larson, D.W.

1976-01-01

A preliminary assessment of heat transfer problems internal to a LMFBR spent fuel shipping cask is reported. The assessment is based upon previous results obtained in full-scale, electrically heated mockups of an LMFBR assembly located in a containing pipe, and also upon analytical and empirical studies presented in this paper. It is shown that a liquid coolant will be required to adequately distribute the decay heat of short-cooled assemblies from the fuel region to the containing cask structure. Liquid sodium apparently provides the best heat transfer, and sufficient data are available to adequately model the heat transfer processes involved. Dowtherm A is the most efficient organic evaluated to date and presented in the open literature. Since the organic materials have high Prandtl and usually high Rayleigh numbers, natural convection is the predominant mode of heat transfer. It is shown that a more comprehensive understanding of the convective processes will be required before heat transfer with an organic coolant can be adequately modeled. However, in view of systems considerations, Dowtherm A should be further considered as an alternative to sodium for use as a LMFBR spent fuel shipping cask coolant

Modeling of Heating and Evaporation of FACE I Gasoline Fuel and its Surrogates

KAUST Repository

Elwardani, Ahmed Elsaid

2016-04-05

The US Department of Energy has formulated different gasoline fuels called \\'\\'Fuels for Advanced Combustion Engines (FACE)\\'\\' to standardize their compositions. FACE I is a low octane number gasoline fuel with research octane number (RON) of approximately 70. The detailed hydrocarbon analysis (DHA) of FACE I shows that it contains 33 components. This large number of components cannot be handled in fuel spray simulation where thousands of droplets are directly injected in combustion chamber. These droplets are to be heated, broken-up, collided and evaporated simultaneously. Heating and evaporation of single droplet FACE I fuel was investigated. The heating and evaporation model accounts for the effects of finite thermal conductivity, finite liquid diffusivity and recirculation inside the droplet, referred to as the effective thermal conductivity/effective diffusivity (ETC/ED) model. The temporal variations of the liquid mass fractions of the droplet components were used to characterize the evaporation process. Components with similar evaporation characteristics were merged together. A representative component was initially chosen based on the highest initial mass fraction. Three 6 components surrogates, Surrogate 1-3, that match evaporation characteristics of FACE I have been formulated without keeping same mass fractions of different hydrocarbon types. Another two surrogates (Surrogate 4 and 5) were considered keeping same hydrocarbon type concentrations. A distillation based surrogate that matches measured distillation profile was proposed. The calculated molar mass, hydrogen-to-carbon (H/C) ratio and RON of Surrogate 4 and distillation based one are close to those of FACE I.

Clean Coal Technology Demonstration Program. Program update 1994

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-04-01

The Clean Coal Technology Demonstration Program (CCT Program) is a $7.14 billion cost-shared industry/government technology development effort. The program is to demonstrate a new generation of advanced coal-based technologies, with the most promising technologies being moved into the domestic and international marketplace. Clean coal technologies being demonstrated under the CCT program are creating the technology base that allows the nation to meet its energy and environmental goals efficiently and reliably. The fact that most of the demonstrations are being conducted at commercial scale, in actual user environments, and under conditions typical of commercial operations allows the potential of the technologies to be evaluated in their intended commercial applications. The technologies are categorized into four market sectors: advanced electric power generation systems; environmental control devices; coal processing equipment for clean fuels; and industrial technologies. Sections of this report describe the following: Role of the Program; Program implementation; Funding and costs; The road to commercial realization; Results from completed projects; Results and accomplishments from ongoing projects; and Project fact sheets. Projects include fluidized-bed combustion, integrated gasification combined-cycle power plants, advanced combustion and heat engines, nitrogen oxide control technologies, sulfur dioxide control technologies, combined SO{sub 2} and NO{sub x} technologies, coal preparation techniques, mild gasification, and indirect liquefaction. Industrial applications include injection systems for blast furnaces, coke oven gas cleaning systems, power generation from coal/ore reduction, a cyclone combustor with S, N, and ash control, cement kiln flue gas scrubber, and pulse combustion for steam coal gasification.

Drying of bio fuel utilizing waste heat; Torkning av biobraenslen med spillvaerme

Energy Technology Data Exchange (ETDEWEB)

Johansson, Inge; Larsson, Sara; Wennberg, Olle [S.E.P. Scandinavian Energy Project AB, Goeteborg (Sweden)

2004-10-01

Many industries today have large sources of low grade heat (waste heat), however this energy is mainly lost with effluents to air and water. The aim of this study has been to investigate the technical and economical aspects of utilizing this low grade heat to dry biofuel. The project has been mainly focused towards the forest industry since they have both large amounts of biofuel and waste heat available. Drying of biofuel could generate added revenue (or reduced purchase costs) and through that also create larger incentives for further energy saving modifications to the main process. Due to the higher moisture content together with the risk of frozen bark in the winter time, additional fuels (such as oil) to combust bark in the existing boiler. This is mainly the case when mechanical dewatering is not available. Drying of bark results in an added energy value, which makes it possible to combust the bark without additional fuel. The primary energy demand, in the form of electricity and optional additional heating at load peaks, is low when waste heat is used for the drying process. In this way it is possible to increase the biofuel potential, since the primary energy input to the drying process is essentially lower then the increased energy value of the fuel. Drying also decreases the biological degradation of the fuel. Taking all the above into consideration, waste heat drying could result in a 25 % increase of the biofuel potential in the forest industry in Sweden, without additional cutting of wood. A survey has been done to state which commercial technologies are available for biofuel drying with waste heat. An inquiry was sent out to a number of suppliers and included a few different cases. Relations for approximating investment cost as well as electric power demand were created based on the answers from the inquiry. These relations have then been used in the economical evaluations made for a number of cases representing both sawmills and pulp and paper mills

A Critical Heat Generation for Safe Nuclear Fuels after a LOCA

Directory of Open Access Journals (Sweden)

Jae-Yong Kim

2014-01-01

Full Text Available This study applies a thermo-elasto-plastic-creep finite element procedure to the analysis of an accidental behavior of nuclear fuel as well as normal behavior. The result will be used as basic data for the robust design of nuclear power plant and fuels. We extended the range of mechanical strain from small or medium to large adopting the Hencky logarithmic strain measure in addition to the Green-Lagrange strain and Almansi strain measures, for the possible large strain situation in accidental environments. We found that there is a critical heat generation after LOCA without ECCS (event category 5, under which the cladding of fuel sustains the internal pressure and temperature for the time being for the rescue of the power plant. With the heat generation above the critical value caused by malfunctioning of the control rods, the stiffness of cladding becomes zero due to the softening by high temperature. The weak position of cladding along the length continuously bulges radially to burst and to discharge radioactive substances. This kind of cases should be avoid by any means.

Modelling and Evaluation of Heating Strategies for High Temperature Polymer Electrolyte Membrane Fuel Cell Stacks

DEFF Research Database (Denmark)

Andreasen, Søren Juhl; Kær, Søren Knudsen

2008-01-01

Experiments were conducted on two different cathode air cooled high temperature PEM (HTPEM) fuel cell stacks; a 30 cell 400W prototype stack using two bipolar plates per cell, and a 65 cell 1 kW commercial stack using one bipolar plate per cell. The work seeks to examine the use of different...... model to simulate the temperature development of a fuel cell stack during heating can be used for assistance in system and control design. The heating strategies analyzed and tested reduced the startup time of one of the fuel cell stacks from 1 h to about 6 min....

Sensitivity of district heating system operation to heat demand reductions and electricity price variations: A Swedish example

International Nuclear Information System (INIS)

Åberg, M.; Widén, J.; Henning, D.

2012-01-01

In the future, district heating companies in Sweden must adapt to energy efficiency measures in buildings and variable fuel and electricity prices. Swedish district heating demands are expected to decrease by 1–2% per year and electricity price variations seem to be more unpredictable in the future. A cost-optimisation model of a Swedish local district heating system is constructed using the optimisation modelling tool MODEST. A scenario for heat demand changes due to increased energy efficiency in buildings, combined with the addition of new buildings, is studied along with a sensitivity analysis for electricity price variations. Despite fears that heat demand reductions will decrease co-generation of clean electricity and cause increased global emissions, the results show that anticipated heat demand changes do not increase the studied system's primary energy use or global CO 2 emissions. The results further indicate that the heat production plants and the fuels used within the system have crucial importance for the environmental impact of district heat use. Results also show that low seasonal variations in electricity price levels with relatively low winter prices promote the use of electric heat pumps. High winter prices on the other hand promote co-generation of heat and electricity in CHP plants. -- Highlights: ► A MODEST optimisation model of the Uppsala district heating system is built. ► The impact of heat demand change on heat and electricity production is examined. ► An electricity price level sensitivity analysis for district heating is performed. ► Heat demand changes do not increase the primary energy use or global CO 2 emissions. ► Low winter prices promote use of electric heat pumps for district heating production.

Clean energy from a carbon fuel cell

Science.gov (United States)

Kacprzak, Andrzej; Kobyłecki, Rafał; Bis, Zbigniew

2011-12-01

The direct carbon fuel cell technology provides excellent conditions for conversion of chemical energy of carbon-containing solid fuels directly into electricity. The technology is very promising since it is relatively simple compared to other fuel cell technologies and accepts all carbon-reach substances as possible fuels. Furthermore, it makes possible to use atmospheric oxygen as the oxidizer. In this paper the results of authors' recent investigations focused on analysis of the performance of a direct carbon fuel cell supplied with graphite, granulated carbonized biomass (biocarbon), and granulated hard coal are presented. The comparison of the voltage-current characteristics indicated that the results obtained for the case when the cell was operated with carbonized biomass and hard coal were much more promising than those obtained for graphite. The effects of fuel type and the surface area of the cathode on operation performance of the fuel cell were also discussed.

Hydrogen energy - Abundant, efficient, clean: A debate over the energy-system-of-change

Energy Technology Data Exchange (ETDEWEB)

Winter, Carl-Jochen [International Association for Hydrogen Energy (IAHE), c/o ENERGON Carl-Jochen Winter e.K., Obere St.-Leonhardstr. 9, 88662 Ueberlingen (Germany)

2009-07-15

Both secondary energies, electricity and hydrogen, have much in common: they are technology driven; both are produced from any available primary energy; once produced both are environmentally and climatically clean over the entire length of their respective conversion chains, from production to utilization; they are electrochemically interchangeable via electrolyses and fuel cells; both rely on each other, e.g., when electrolyzers and liquefiers need electricity or when electricity-providing low temperature fuel cells need hydrogen; in cases of secondary energy transport over longer distances they compete with each other; in combined fossil fuel cycles both hydrogen and electricity are produced in parallel exergetically highly efficiently; hydrogen in addition to electricity helps exergizing the energy system and, thus, maximizing the available technical work. There are dissimilarities, too: electricity transports information, hydrogen does not; hydrogen stores and transports energy, electricity does not (in macroeconomic terms). The most obvious dissimilarity is their market presence, both in capacities and in availability: Electricity is globally ubiquitous (almost), whilst hydrogen energy is still used in only selected industrial areas and in much smaller capacities. The article describes in 15 chapters, 33 figures, 3 tables, and 2 Annexes the up-and-coming hydrogen energy economy, its environmental and climatic relevance, its exergizing influence on the energy system, its effect on decarbonizing fossil fueled power plants, the introduction of the novel non-heat-engine-related electrochemical energy converter fuel cell in portable electronics, in stationary and mobile applications. Hydrogen guarantees environmentally and climatically clean transportation on land, in air and space, and at sea. Hydrogen facilitates the electrification of vehicles with practically no range limits. (author)

Heaters to simulate fuel pins for heat transfer tests in single-phase liquid-metal-flow

International Nuclear Information System (INIS)

Casal, V.; Graf, E.; Hartmann, W.

1976-09-01

The development of heaters for thermal simulation of the fuel elements of liquid metal cooled fast breeder reactors (SNR) is reported. Beginning with the experimental demands various heating methods are discussed for thermodynamic investigations of the heat transfer in liquid metals. Then a preferred heater rod is derived to simulate the fuel pins of a SNR. Finally it is reported on the fabrication and the operation practice. (orig.) [de

CleanFleet. Final report: Executive summary

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-12-01

CleanFleet, formally known as the South Coast Alternative Fuels Demonstration, was a comprehensive demonstration of alternative fuel vehicles (AFVs) in daily commercial service. Between April 1992 and September 1994, five alternative fuels were tested in 84 panel vans: compressed natural gas (CNG), propane gas, methanol as M-85, California Phase 2 reformulated gasoline (RFG), and electricity. The AFVs were used in normal FedEx package delivery service in the Los Angeles basin alongside 27 {open_quotes}control{close_quotes} vans operating on regular gasoline. The liquid and gaseous fuel vans were model year 1992 vans from Ford, Chevrolet, and Dodge. The two electric vehicles (EVs) were on loan to FedEx from Southern California Edison. The AFVs represented a snapshot in time of 1992 technologies that (1) could be used reliably in daily FedEx operations and (2) were supported by the original equipment manufacturers (OEMs). A typical van is shown in Figure 2. The objective of the project was to demonstrate and document the operational, emissions, and economic status of alternative fuel, commercial fleet delivery vans in the early 1990s for meeting air quality regulations in the mid to late 1990s. During the two-year demonstration, CleanFleet`s 111 vehicles travelled more than three million miles and provided comprehensive data on three major topics: fleet operations, emissions, and fleet economics. Fleet operations were examined in detail to uncover and resolve problems with the use of the fuels and vehicles in daily delivery service. Exhaust and evaporative emissions were measured on a subset of vans as they accumulated mileage. The California Air Resources Board (ARB) measured emissions to document the environmental benefits of these AFVs. At the same time, CleanFleet experience was used to estimate the costs to a fleet operator using AFVs to achieve the environmental benefits of reduced emissions.

Economic analysis of using excess renewable electricity to displace heating fuels

DEFF Research Database (Denmark)

Pensini, Alessandro; Rasmussen, Claus Nygaard; Kempton, Willett

2014-01-01

. Because excess electricity appears to be cost-optimum, this raises the question as to whether the excess electricity, which in the case of wind power is predominately produced in colder weather, might displace other fuels for purposes such as heat. This study models using excess electricity for heating......, based on an analysis of electricity and heat use in a TSO in the North-Eastern part of the United States (PJM Interconnection). The heating system was modeled as heat pump based district heating (HPDH) with thermal energy storage (TES). Thus, excess electricity is transformed into heat, which is easy....... An algorithm that calculates the total cost of a unit of heat was used to determine the economically optimal size of the system’s main components and the influence that natural gas (NG) and electricity prices have on this optimum. It was found that a system based on heat pumps (HP) and centralized thermal...

Fuel element services

International Nuclear Information System (INIS)

Marta, H.; Alvarez, P.; Jimenez, J.

2006-01-01

Refuelling outages comprise a number of maintenance tasks scheduled long in advance to assure a reliable operation throughout the next cycle and, in the long run, a safer and more efficient plant. Most of these tasks are routine service of mechanical and electrical system and likewise fuel an be considered a critical component as to handling, inspection, cleaning and repair. ENUSA-ENWESA AIE has been working in this area since 1995 growing from fuel repair to a more integrated service that includes new and spent fuel handling, inserts, failed fuel rod detection systems, ultrasonic fuel cleaning, fuel repair and a comprehensive array of inspection and tests related to the reliability of the mechanical components in the fuel assembly, all this, performed in compliance with quality, safety, health physics and any other nuclear standard. (Author)

Carbon deposition on 20/25/Nb steel using an electrically heated AGR fuel pin

International Nuclear Information System (INIS)

Blanchard, A.; Campion, P.

1980-01-01

The radiolysis of carbon dioxide in gas-cooled reactors leads to the production of active species capable of reacting with the graphite moderator to form carbon monoxide with a resultant gradual loss of moderator. In the early days of gas-cooled reactor design, the intention was to allow the carbon monoxide concentration to increase and use this reaction product to inhibit the initial radiolysis of the carbon dioxide. Exploratory irradiation experiments using 4 to 7% carbon monoxide revealed that low density deposits ranging in colour from light grey through brown to black were found in the temperature range 470 to 600 K. In view of the fact that this type of deposition could adversely affect heat transfer processes in both fuel channels and heat exchangers, together with the fact that carbon monoxide was not sufficiently powerful as a graphite oxidation inhibitor, methane was selected as the primary inhibitor for the AGR series of power stations. This paper describes some carbon deposition experiments using an electrically heated 'dummy fuel element' linked to a recirculating carbon dioxide irradiation loop in which carbon monoxide concentration, methane concentration, fuel pin temperature and the chemical nature of the fuel pin surface were varied. (author)

Reaction layer growth and reaction heat of U-Mo/Al dispersion fuels using centrifugally atomized powders

International Nuclear Information System (INIS)

Ryu, Ho Jin; Han, Young Soo; Park, Jong Man; Park, Soon Dal; Kim, Chang Kyu

2003-01-01

The growth behavior of reaction layers and heat generation during the reaction between U-Mo powders and the Al matrix in U-Mo/Al dispersion fuels were investigated. Annealing of 10 vol.% U-10Mo/Al dispersion fuels at temperatures from 500 to 550 deg. C was carried out for 10 min to 36 h to measure the growth rate and the activation energy for the growth of reaction layers. The concentration profiles of reaction layers between the U-10Mo vs. Al diffusion couples were measured and the integrated interdiffusion coefficients were calculated for the U and Al in the reaction layers. Heat generation of U-Mo/Al dispersion fuels with 10-50 vol.% of U-Mo fuel during the thermal cycle from room temperature to 700 deg. C was measured employing the differential scanning calorimetry. Exothermic heat from the reaction between U-Mo and the Al matrix is the largest when the volume fraction of U-Mo fuel is about 30 vol.%. The unreacted fraction in the U-Mo powders increases as the volume fraction of U-Mo fuel increases from 30 to 50 vol.%

Description of heat flux measurement methods used in hydrocarbon and propellant fuel fires at Sandia.

Energy Technology Data Exchange (ETDEWEB)