• 제목/요약/키워드: fuel pellet

검색결과 252건 처리시간 0.033초

COSMOS : A Computer Code for the Analysis of LWR $UO_2$ and MOX Fuel Rod

  • Koo, Yang-Hyun;Lee, Byung-Ho;Sohn, Dong-Seong
    • Nuclear Engineering and Technology
    • /
    • 제30권6호
    • /
    • pp.541-554
    • /
    • 1998
  • A computer code COSMOS has been developed based on the CARO-D5 for the thermal analysis of LWR UO$_2$ and MOX fuel rod under steady-state and transient operating conditions. The main purpose of the COSMOS, which considers high turnup characteristics such as thermal conductivity degradation with turnup and rim formation at the outer part of fuel pellet, is to calculate temperature profile across fuel pellet and fission gas release up to high burnup. A new mechanistic fission gas release model developed based on physical processes has been incorporated into the code. In addition, the features of MOX fuel such as change in themo-mechanical properties and the effect of microscopic heterogeneity on fission gas release have been also taken into account so that it can be applied to MOX fuel. Another important feature of the COSMOS is that it can analyze fuel segment refabricated from base irradiated fuel rods in commercial reactors. This feature makes it possible to analyze database obtained from international projects such as the MALDEN and RISO, many of which were collected from refabricated fuel segments. The capacity of the COSMOS has been tested with some number of experimental results obtained from the HALDEN, RISO and FIGARO programs. Comparison with the measured data indicates that, although the COSMOS gives reasonable agreement, the current models need to be improved. This work is being performed using database available from the OECD/NEA.

  • PDF

산업용 대마 목부를 이용한 고밀화 펠릿 연료 제조 (Densified Pellet Fuel from Woody Core of Industrial Hemp)

  • 신수정;한규성;심화섭;안병국
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 한국신재생에너지학회 2008년도 춘계학술대회 논문집
    • /
    • pp.221-224
    • /
    • 2008
  • We made densified wood pellet by hemp woody core as replacing wood resource. Hemp was separated into the bast fiber and the woody core by hot steaming treatment. The hemp woody core had a similar lignin content and carbohydrate composition with hardwood. Also, the hemp had a low ash content, which resulted in a low ash formation in pellet burning. Heating value of the hemp pellet had a very similar to the pellet made by hardwoods. The hemp woody core can replace hardwood for densified wood pelletmaking.

  • PDF

안전성이 높은 산업용 목재펠릿 보일러 개발 (Development of Industrial Wood Pellet Boiler with High Safety)

  • 정찬홍;박민철;이성영
    • 한국신뢰성학회지:신뢰성응용연구
    • /
    • 제13권1호
    • /
    • pp.31-44
    • /
    • 2013
  • Recently, due to the high rise of energy costs and environmental problem issues, much attention has been paid to wood pellets. Wood pellets are produced by compressing woody biomass into cylindrical form. Wood pellets are suitable for use at various scales in industrial furnaces for heat production to replace conventional fossil fuel energy sources since the use of wood pellet that is carbon neutral can alleviate global warming. This study presents the result of developing two industrial wood pellet boilers with high safety having capacities of 290kW and 440kW. Efficiency has been improved by using a rotating screw bar grate burner. Special attention has been paid to the improvement of the safety of the wood pellet boilers from backfire by adopting a triple protecting system composed of a rotary feeder, an air curtain, and a backfire protecting DC-fan.

해외 바이오매스 에너지자원 확보를 위한 기초조사 1 - 팜 바이오매스 (Basic Study on Oversea Biomass Energy Resources 1 - Palm Biomass)

  • 이형우
    • Journal of the Korean Wood Science and Technology
    • /
    • 제42권4호
    • /
    • pp.439-449
    • /
    • 2014
  • 2012년 신재생에너지공급의무화제도 시행으로 국내 목재펠릿 수요가 급증하고 있으나, 현재 우리나라의 목재펠릿 자급률은 10% 수준에 머물러, 급증하는 수요를 충족하기 어려울 것으로 예상된다. 따라서 안정적인 공급과 가격이 보장될 수 있는 새로운 바이오매스의 발굴을 통하여 목재펠릿에 대한 폭발적인 수요를 대체하는 일은 우리뿐만 아니라 세계적으로 시급한 과제라 할 수 있다. 본 연구의 분석결과 고체 팜 바이오매스 중 대표적인 EFB (empty fruit bunch)와 MF (mesocarp fiber)의 2012년도 연간 발생량(함수율 10% 기준)이 말레이시아와 인도네시아에서 각각 약 2,800만톤과 2,000만 톤으로, 두 지역에서만 연간 총 4,800만 톤이 발생되는 것으로 추정된다. 연료적 특성에 있어서도 EFB의 발열량이 목재의 90% 수준을 상회하므로 목재펠릿을 대체할 수 있는 우수한 바이오매스 에너지자원이라 할 수 있다. 다만, 높은 회분함량으로 인하여 주택이나 온실의 난방용으로는 부적합하지만 발전용이나 산업용으로는 충분히 사용가능할 것으로 판단된다.

Study on the Fluidized-Bed Drying Characteristics of Sawdust as a Raw-Material for Wood-Pellet Fuel

  • Lee, Hyoung-Woo
    • Journal of the Korean Wood Science and Technology
    • /
    • 제34권2호
    • /
    • pp.30-36
    • /
    • 2006
  • Wood fuel must be dried before combustion to minimize the energy loss. Sawdust of Japanese red pine was dried in a batch type fluidized-bed to investigate the drying characteristics of sawdust as a raw material for bio-fuel. The minimum fluidization air velocity was increased as particle size was increased. It took about 21 minutes and 8 minutes to dry 0.08 m-deep bed of particles with average particle size of 1.3 mm from 100% to 10% moisture content at air temperature of $20^{\circ}C$ and $50^{\circ}C$, respectively.

농업부문에서 신재생에너지로의 연료전환이 시설원예에 미치는 영향 분석 -목재펠릿을 중심으로- (Fuel Conversion to Renewable Energy Analysis of the Impact on the Horticulture in the Agricultural Sector -Mainly Wood Pellets-)

  • 윤성이;김태곤
    • 한국유기농업학회지
    • /
    • 제22권4호
    • /
    • pp.531-547
    • /
    • 2014
  • This study analyzed the effect of Greenhouse of wood pellet fuel conversing from Diesel. Analyzed through a life cycle assessment of greenhouse gas emissions of carbon dioxide for the environmental assessment, In evaluation of the Ministry of the Environment, analyzed through the life cycle assessment of carbon dioxide emissions of the greenhouse gas and, In the case of economic evaluation, we analyzed the investment payback period to the total revenue generated by each of the calculated incentive based on the RHI and institutions reduction projects a reduction of costs associated with the reduction of fuel costs.

안전성을 고려한 고효율 목재펠릿 보일러 개발 (Development of a High Efficiency Wood Pellet Boiler with Improved Safety)

  • 정찬홍;박민철
    • 한국신뢰성학회지:신뢰성응용연구
    • /
    • 제12권1호
    • /
    • pp.35-46
    • /
    • 2012
  • Wood pellet is one of biomass energy fuels, which is produced by compressing woody biomass such as sawdust, planer shavings, and whole-tree removal or tree tops and branches leftover after logging into cylindrical form. Latterly much attention has been paid to wood pellet boiler which is suitable for use at various scales in domestic and industrial furnaces for heat production to replace conventional fossil fuel energy sources since the use of wood pellet that is carbon neutral can alleviate global warming. This study presents the result of developing a high efficiency wood pellet boiler with 55MJ/h capacity. Efficiency has been improved by using a rotating disk burner with a shorter screw feeder. Special attention has been paid to the improvement of the safety of the wood pellet boiler from backfire by adopting a double protecting system composed of a shutter and an air curtain. The result shows that the efficiencies of the wood pellet boiler are 97.2% and 89.2% based on lower and higher heating values, respectively, at 15.1kW of heating output.

PROGRESS IN NUCLEAR FUEL TECHNOLOGY IN KOREA

  • Song, Kun-Woo;Jeon, Kyeong-Lak;Jang, Young-Ki;Park, Joo-Hwan;Koo, Yang-Hyun
    • Nuclear Engineering and Technology
    • /
    • 제41권4호
    • /
    • pp.493-520
    • /
    • 2009
  • During the last four decades, 16 Pressurized Water Reactors (PWR) and 4 Pressurized Heavy Water Reactors (PHWR) have been constructed and operated in Korea, and nuclear fuel technology has been developed to a self-reliant state. At first, the PWR fuel design and manufacturing technology was acquired through international cooperation with a foreign partner. Then, the PWR fuel R&D by Korea Atomic Energy Research Institute (KAERI) has improved fuel technology to a self-reliant state in terms of fuel elements, which includes a new cladding material, a large-grained $UO_2$ pellet, a high performance spacer grid, a fuel rod performance code, and fuel assembly test facility. The MOX fuel performance analysis code was developed and validated using the in-reactor test data. MOX fuel test rods were fabricated and their irradiation test was completed by an international program. At the same time, the PWR fuel development by Korea Nuclear Fuel (KNF) has produced new fuel assemblies such as PLUS7 and ACE7. During this process, the design and test technology of fuel assemblies was developed to a self-reliant state. The PHWR fuel manufacturing technology was developed and manufacturing facility was set up by KAERI, independently from the foreign technology. Then, the advanced PHWR fuel, CANFLEX(CANDU Flexible Fuelling), was developed, and an irradiation test was completed in a PHWR. The development of the CANFLEX fuel included a new design of fuel rods and bundles.. The nuclear fuel technology in Korea has been steadily developed in many national R&D programs, and this advanced fuel technology is expected to contribute to a worldwide nuclear renaissance that can create solutions to global warming.

1D AND 3D ANALYSES OF THE ZY2 SCIP BWR RAMP TESTS WITH THE FUEL CODES METEOR AND ALCYONE

  • Sercombe, J.;Agard, M.;Struzik, C.;Michel, B.;Thouvenin, G.;Poussard, C.;Kallstrom, K.R.
    • Nuclear Engineering and Technology
    • /
    • 제41권2호
    • /
    • pp.187-198
    • /
    • 2009
  • In this paper, three power ramp tests performed on high burn-up Re-crystallized Zircaloy2 - UO2 BWR fuel rods (56 to 63 MWd/kgU) within the SCIP project are simulated with METEOR and ALCYONE 3D. Two of the ramp tests are of staircase type up to Linear Heat Rates of 420 and 520 W/cm and with long holding periods. Failure of the 420 W/cm fuel rod was observed after 40 minutes. The third ramp test consisted of a more standard ramp test with a constant power rate of 80 W/cm/min up to 410 W/cm with a short holding time. The tests were first simulated with the METEOR 1D fuel rod code, which gave accurate results in terms of profilometry and fission gas releases. The behaviour of a fuel pellet fragment and of the cladding piece on top of it was then investigated with ALCYONE 3D. The size and the main characteristics of the ridges after base irradiation and power ramp testing were recovered. Finally, the failure criteria validated for PWR conditions and fuel rods with low-to-medium burn-ups were used to analyze the failure probability of the KKL rodlets during ramp testing.