• 방사성폐기물학회지
• /
• 제21권2호
• /
• pp.255-269
• /
• 2023

Compared to operational wastes, nuclear power plant (NPP) decommissioning wastes are generated in larger quantities within a short time and include diverse types with a wider range of radiation characteristics. Currently used 200 L drums and IP-2 type transport containers are inefficient and restrictive in packaging and transporting decommissioning wastes. Therefore, new packaging and transport containers with greater size, loading weight, and shielding performance have been developed. When transporting radioactive materials, radiological safety should be assessed by reflecting parameters such as the type and quantity of the package, transport route, and transport environment. Thus far, safety evaluations of radioactive waste transport have mainly targeted operational wastes, that have less radioactivity and a smaller amount per transport than decommissioning wastes. Therefore, in this study, the possible radiation effects during the transport from NPP to disposal facilities were evaluated to reflect the characteristics of the newly developed containers and decommissioning wastes. According to the evaluation results, the exposure dose to transport workers, handling workers, and the public was lower than the domestic regulatory limit. In addition, all exposure dose results were confirmed, through sensitivity analysis, to satisfy the evaluation criteria even under circumstances when radioactive materials were released 100% from the container.

• 방사성폐기물학회지
• /
• 제12권2호
• /
• pp.165-169
• /
• 2014

원자력발전을 지속가능한 에너지원으로 활용하기 위해서는 원전 해체 및 운영 과정에서 발생하는 방사성폐기물의 안전하고 효율적인 처분이 매우 중요하다. 방사성폐기물 종류는 다양하지만 해체과정에서 가장 많이 발생할 것으로 예상되는 극저준위방사성폐기물 인수기준수립은 원전해체전략수립에 큰 영향을 줄 것으로 보인다. 본 연구에서는 영국과 미국의 극저준위방사성폐기물처분장 인수기준을 경주에 건설 중인 원자력환경센터의 인수기준과 비교분석을 통해 향후 우리나라 극저준위방사성폐기물 처분을 위한 폐기물 인수기준을 분석하고자 한다.

• 한국방사성폐기물학회:학술대회논문집
• /
• 한국방사성폐기물학회 2019년도 춘계학술논문요약집
• /
• pp.211-212
• /
• 2019

• 한국방사성폐기물학회:학술대회논문집
• /
• 한국방사성폐기물학회 2005년도 Proceedings of The 6th korea-china joint workshop on nuclear waste management
• /
• pp.290-299
• /
• 2005

Two decommissioning projects are carried out at the KAERI (Korean Atomic Energy Research Institute), one for the Korea research reactors, KRR-1 and KRR-2, and another for the uranium conversion plant (UCP). The concept of the management of the wastes from the decommissioning sites was reviewed with a relation of the decommissioning strategies, technologies for the treatment and the decontamination, and the characteristics of waste. All the liquid waste generated from KRR-1 and KRR-2 decommissioning site is evaporated by a solar evaporation facility and all the liquid waste from the UCP is treated together with lagoon sludge waste. The solid wastes from the decommissioning sites are categorized into three groups; not contaminated, restricted releasable and radioactive waste. The not-contaminated waste will be reused and/or disposed at an industrial disposal site, and the releasable waste is stored for the future disposal at the KAERI. The radioactive waste is packed in containers, and will be stored at the decommissioning sites till they are sent to a national repository site. The reduction of the radioactive solid waste is one of the strategies for the decommissioning projects and could be achieved by the repeated decontamination. By the achievement of the minimization strategy, the amount of radioactive waste was reduced and the disposal cost will be reduced, but the cost for manpower, for direct materials and for administration was increased.

• Nuclear Engineering and Technology
• /
• 제53권7호
• /
• pp.2261-2267
• /
• 2021

This paper evaluates the efficacy of magnesium potassium phosphate cements (MKPCs) as waste forms for the solidification of radioactive concrete powder wastes produced by the decommissioning of nuclear power plants. MKPC specimens that contained up to 50 wt% of simulated concrete powder wastes (SCPWs) were evaluated. We measured the porosity and compressive strength of the MKPC specimens, observing them using scanning electron microscopy and X-ray diffraction. The addition of SCPWs reduced the porosity and increased the compressive strength of the MKPC specimens. Struvite-K crystals were well-synthesized, and no additional crystal phase was formed. After thermal cycling and after immersion, MKPC specimens with 50 wt% SCPWs satisfied the waste-acceptance criteria (WAC) for compressive strength. Semi-dynamic leaching tests were performed using the ANS 16.1 method; the leachability indices of Cs, Co, and Sr were 11.45, 17.63, and 15.66, respectively, which also satisfy the WAC. Thus, MKPCs can provide stable matrices to immobilize radioactive concrete wastes generated by the decommissioning of nuclear power plants.

• 방사성폐기물학회지
• /
• 제11권3호
• /
• pp.213-227
• /
• 2013

원자로시설 해체계획서 작성은 원자로시설의 안전한 해체, 해체폐기물의 발생 최소화, 사람과 환경 보호 등을 위해 원자로시설 해체에 앞서 반드시 필요하다. 우리나라는 고리 1호기, 월성 1호기가 머지않은 시기에 해체를 맞이하게 되지만, 해체계획서를 작성하는데 필요한 관련 세부 지침이 미비한 상황이다. 이에 따라 본 논문에서는 IAEA의 원자력 국제 안전기준과 원자로시설 해체경험과 선진화된 규제체계를 보유하고 있는 미국, 영국, 프랑스의 해체계획서 작성 지침을 비교분석하고 국내 상황을 감안하여 원자로시설 해체계획서 세부 작성지침(안)을 개발하였다. 본 논문에서 개발한 작성지침(안)은 국내 원자로시설 해체 관련 법령을 정비하고 해체사업자가 원자로시설을 해체하고자 할 때 미리 준비사항을 알려주는 역할을 할 것으로 기대되고 있다.

• 한국방사성폐기물학회:학술대회논문집
• /
• 한국방사성폐기물학회 2003년도 가을 학술논문집
• /
• pp.645-649
• /
• 2003

제염 해체 설계단계에서 예견하였던 것과는 다르게 실제 제염$\cdot$해체 과정에서는 다양한 조건과 상황이 야기됨으로써, 실제 폐기물의 특성과 양이 당초 예상과는 다른 금속성 폐기물도 발생하게 된다. 이러한 금속성 폐기물을 관리하기 위한 관리시스템을 분석하고, 이에 대한 최적 처리방법 및 공정을 선정할 수 있는 단위기술을 고찰하였다. 또한 원자력시설 제염$\cdot$해체 동안 예견되는 상황에서 사용할 수 있는 적절한 기술과 공정관리시스템도 도출하였다.

• 방사성폐기물학회지
• /
• 제20권1호
• /
• pp.65-98
• /
• 2022

The nuclear legacy that remains in the United Kingdom (UK) is complex and diverse. Consisting of legacy ponds and silos, redundant reprocessing plants, research facilities, and non-standard or one-off reactor designs, the clean-up of this legacy is under the stewardship of the Nuclear Decommissioning Authority (NDA). Through a mix of prompt and delayed decommissioning strategies, the NDA has made great strides in dealing with the UK's nuclear legacy. Fuel debris and sludge removal from the legacy ponds and silos situated at Sellafield, as part of a prompt decommissioning strategy for the site, has enabled intolerable risks to be brought under control. Reactor defueling and waste retrievals across the Magnox fleet is enabling their transition to a period of care and maintenance; accelerated through the adopted 'Lead and Learn' approach. Bespoke decommissioning methods implemented by the NDA have also enabled the relevant site licence companies to tackle non-standard reactor designs and one-off wastes. Such approaches have potential to influence and shape nuclear decommissioning decision making activities globally, including in Korea.

• 방사성폐기물학회지
• /
• 제17권2호
• /
• pp.203-212
• /
• 2019

처분 부적합 폐기물이란 원전운영이나 해체 시 처리, 고화 및 포장이 요구되는 방사성폐기물 등을 일컬으며, 대표적으로 분산 특성을 갖는 입자성 방사성폐기물을 예로 들 수가 있다. 이들 폐기물에는 원전 운영과정에서 발생되는 농축폐액의 건조분말, 슬러리 및 슬러지, 향후 원전 해체과정에서 발생되는 온갖 분말 상태의 폐기물(콘크리트 파쇄물, 제염 슬러지 등), 그리고 제염이 용이치 못한 미세 크기의 방사능오염 토양 등이 있다. 입자성 폐기물을 기존의 고화방식으로 처리할 경우에는 최종 폐기물의 부피가 증가하는 단점을 갖게 되어 처분 비용의 증가 및 처분장의 수용성을 감소하는 결과를 야기할 수가 있다. 따라서 이들 문제를 해결하고자 본 연구에서는 최종 폐기물 부피의 감용화를 위해 롤 압축 기술을 이용하여 분말의 펠렛화 연구를 수행하였다.

• 방사성폐기물학회지
• /
• 제21권2호
• /
• pp.247-253
• /
• 2023

According to NSSC Notice No. 2021-10, safety analysis needs to be introduced in the decommissioning plan. Public and occupational dose analyses should be conducted, specifically for unexpected radiological accidents. Herein, based on the risk matrix and analytic hierarchy process, the method of selecting accident scenarios during the decommissioning of nuclear power plants has been proposed. During decommissioning, the generated spent resin exhibits relatively higher activity than other generated wastes. When accidents occur, the release fraction varies depending on the conditioning method of radioactive waste and type of radioactive nuclides or accidents. Occupational dose analyses for 2 (fire and drop) among 11 accident scenarios have been performed. The radiation doses of the additional exposures caused by the fire and drop accidents are 1.67 and 4.77 mSv, respectively.