• 제목/요약/키워드: spent nuclear fuels

검색결과 202건 처리시간 0.03초

Development of a Teleoperated Manipulator System for Remote Handling of Spent Fuel Bundles

  • Ahn Sung Ho;Jin Jae Hyun;Yoon Ji Sup
    • Nuclear Engineering and Technology
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    • 제35권3호
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    • pp.214-225
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    • 2003
  • A teleoperated manipulator system has been developed for remote handling of the spent fuel bundles. A heavy-duty power manipulator with high reduction ratio joints is used for the slave manipulator in the developed system since the handling tasks of the spent fuel bundles need power. Also, the universal type master manipulator, which has force reflecting capability, is used for precise remote manipulation. The power manipulators so frequently occur the control input saturation that the precise control performances are not achieved due to the windup phenomenon. An advanced bilateral control scheme compensating for the saturation is applied to the teleoperated manipulator system. The validity of the developed system is verified by the grid cutting and fuel transportation tasks from the mockup spent fuel bundle.

High-efficiency deep geological repository system for spent nuclear fuel in Korea with optimized decay heat in a disposal canister and increased thermal limit of bentonite

  • Jongyoul Lee;Kwangil Kim;Inyoung Kim;Heejae Ju;Jongtae Jeong;Changsoo Lee;Jung-Woo Kim;Dongkeun Cho
    • Nuclear Engineering and Technology
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    • 제55권4호
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    • pp.1540-1554
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    • 2023
  • To use nuclear energy sustainably, spent nuclear fuel, classified as high-level radioactive waste and inevitably discharged after electricity generation by nuclear power plants, must be managed safely and isolated from the human environment. In Korea, the land area is limited and the amount of high-level radioactive waste, including spent nuclear fuels to be disposed, is relatively large. Thus, it is particularly necessary to maximize disposal efficiency. In this study, a high-efficiency deep geological repository concept was developed to enhance disposal efficiency. To this end, design strategies and requirements for a high-efficiency deep geological repository system were established, and engineered barrier modules with a disposal canister for pressurized water reactor (PWR)-type and pressurized heavy water reactor type Canada deuterium uranium (CANDU) plants were developed. Thermal and structural stability assessments were conducted for the repository system; it was confirmed that the system was suitable for the established strategies and requirements. In addition, the results of the nuclear safety assessment showed that the radiological safety of the new system met the Korean safety standards for disposal of high-level radioactive waste in terms of radiological dose. To evaluate disposal efficiency in terms of the disposal area, the layout of the developed disposal areas was assessed in terms of thermal limits. The estimated disposal areas were 2.51 km2 and 1.82 km2 (existing repository system: 4.57 km2) and the excavated host rock volumes were 2.7 Mm3 and 2.0 Mm3 (existing repository system: 4.5 Mm3) for thermal limits of 100 ℃ and 130 ℃, respectively. These results indicated that the area and the excavated volume of the new repository system were reduced by 40-60% compared to the existing repository system. In addition, methods to further improve the efficiency were derived for the disposal area for deep geological disposal of spent nuclear fuel. The results of this study are expected to be useful in establishing a national high-level radioactive waste management policy, and for the design of a commercial deep geological repository system for spent nuclear fuels.

CANDU 사용후핵연료 처분시스템 효율향상 개념 도출 (Alternative Concept to Enhance the Disposal Efficiency for CANDU Spent Fuel Disposal System)

  • 이종열;조동건;국동학;이민수;최희주
    • 방사성폐기물학회지
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    • 제9권3호
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    • pp.169-179
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    • 2011
  • 우리나라에서 운영하는 원자력발전소는 PWR형과 CANDU형 2종류가 있으며, 원자력발전에 의한 지속적인 에너지 공급을 위하여 이들로부터 발생하는 사용후핵연료에 대한 안전관리는 매우 중요한 인자이다. 사용후핵연료 처분을 위한 연구는 1997년부터 시작하여 한국형 사용후핵연료 처분시스템을 개발하였으며, 현재는 개발된 기술에 대한 실증 및 처분시스템의 효율향상을 위한 연구를 진행하고 있다. 또한, PWR형 사용후핵 연료의 경우 사용후핵연료 재활용 공정을 거쳐 원료물질로 다시 사용하는 연구가 진행 중이므로, 이들 공정으로부터 발생하는 고준위폐기물을 처분하는 방안을 강구하고 있다. 이에 따라 본 논문에서는 PWR형과 CANDU형 사용후핵연료 모두를 직접 처분하는 개념으로 개발한 한국형 사용후핵연료 처분시스템을 바탕으로 CANDU형 사용후핵연료 처분 시스템의 처분효율을 향상시키는 방안을 도출하고자 하였다. 이를 위하여, 한국형 사용후핵연료 처분시스템의 CANDU 사용후핵연료 처분용기를 개선하여 현재 원자력발전소에서 사용하고 있는 사용후핵연료 60 다발(Bundle) 용량의 저장바스켓을 포장 활용하는 개념을 도출하고, 열해석을 통하여 처분시스템 완충재의 온도가 $100^{\circ}C$를 넘지 않도록 하는 요건을 만족하는 처분터널 및 처분공 간격을 정하여 이들에 대한 처분시스템 개념을 도출하였다. 이렇게 설정된 개념들을 단위면적당 열효율, 우라늄밀도(U-density), 처분면적, 굴착량, 완충재 및 폐쇄 물질량 측면에서 분석하여 처분효율이 가장 높은 방안을 제안하였다. 본 연구의 결과는 추후 실제 부지특성자료와 연계하여 PWR 사용후핵연료 재활용공정으로부터 발생한 고준위폐기물 처분시스템과 함께 복합 처분장 설계에 활용될 것이다.