• 설비공학논문집
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• 제22권8호
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• pp.545-552
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• 2010

Research and development efforts to reduce $CO_2$ emission are in progress to cope with global warming. $CO_2$ emission from fossil fuel fired power plants is a major greenhouse gas source and the post-combustion $CO_2$ capture is considered as a short or medium term option to reduce $CO_2$ emissions. In this study, the application of the post-combustion $CO_2$ capture system, which is based on chemical absorption and stripping processes, to typical fossil fuel fired power plants was investigated. A coal fired plant and a natural gas fired combined cycle plant were selected. Performance of the MEA-based $CO_2$ capture system combined with power plants was analyzed and overall plant performance including the energy consumption of the $CO_2$ capture process was investigated.

• Elastomers and Composites
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• 제55권3호
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• pp.222-228
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• 2020

Rubber materials, used in nuclear power plants, need high heat-oxidation resistance to curing or cracking under a heat aging environment. This is because they are applied to environments with high temperature, high humidity, and radiation exposure. Nuclear radiation causes additional hardening or degradation, therefore, rubber materials need radiation resistance that satisfies the general and any accidental conditions produced in the power plant. Therefore, in this study, we developed a rubber material with excellent heat and radiation resistance for the diaphragm seal of a nuclear steam generator nozzle dam. The rubber material greatly improved the reliability of the steam generator nozzle dam. In addition, 30 inch and 42 inch diaphragm seals were manufactured using the developed rubber material. A nozzle dam was installed in a nuclear power plant and tested under the same conditions as a steam generator to evaluate safety and reliability. In the future, the performance and safety of diaphragm seals developed through field tests of nuclear power plants will be evaluated and applied to currently operating and new nuclear power plants.

• 한국안전학회지
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• 제34권5호
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• pp.159-166
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• 2019

The seismic PSA is to probabilistically estimate the potential damage that a large earthquake will cause to a nuclear power plant. It integrates the probabilistic seismic hazard analysis, seismic fragility analysis, and system analysis and is utilized to identify seismic vulnerability and improve seismic capacity of nuclear power plants. Recently, the seismic risk of domestic multi-unit nuclear power plant sites has been evaluated after the Great East Japan Earthquake and Gyeongju Earthquake in Korea. However, while the currently available methods for system analysis can derive basic required results of seismic PSA, they do not provide the detailed results required for the efficient improvement of seismic capacity. Therefore, for in-depth seismic risk evaluation, improved system analysis method for seismic PSA has become necessary. This study develops a system analysis method that is not only suitable for multi-unit seismic PSA but also provides risk information for the seismic capacity improvements. It will also contribute to the enhancement of the safety of nuclear power plants by identifying the seismic vulnerability using the detailed results of seismic PSA. In addition, this system analysis method can be applied to other external event PSAs, such as fire PSA and tsunami PSA, which require similar analysis.

• Nuclear Engineering and Technology
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• 제52권12호
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• pp.2812-2820
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• 2020

House load operation (HLO) occurs when the generator supplies power to the house load without triggering reactor trips during grid disturbances. In Korea, the HLO capability of optimized power reactor 1000 (OPR1000) plants has prevented several reactor trips. Operational experiences demonstrate the difference in the reactor trip incidence due to grid disturbances between OPR1000 plants and Westinghouse plants in Korea, attributable to the availability of the HLO capability. However, probabilistic safety assessments (PSAs) for OPR1000 plants have not considered their specific design features in the initiating event analyses. In an at-power PSA, the HLO capability can affect the initiating event frequencies of general transients (GTRN) and loss of offsite power (LOOP), resulting from transients within the grid system. The initiating event frequencies of GTRN and LOOP for an OPR1000 plant are reduced by 17.7% and 78.7%, respectively, compared to the Korean industry-average initiating event frequencies, and its core damage frequency from internal events is reduced by 15.2%. The explicit consideration of the HLO capability in initiating event analyses makes significant changes in the risk contributions of the initiating events. Consequently, for more realistic at-power PSAs in Korea, we recommend incorporating plant-specific HLO-related design features when estimating initiating event frequencies.

• Nuclear Engineering and Technology
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• 제38권8호
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• pp.697-732
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• 2006

In this paper, a historical review of the developments in the safety of LWR power plants is presented. The paper reviews the developments prior to the TMI-2 accident, i.e. the concept of the defense in depth, the design basis, the large LOCA technical controversies and the LWR safety research programs. The TMI-2 accident, which became a turning point in the history of the development of nuclear power is described briefly. The Chernobyl accident, which terrified the world and almost completely curtailed the development of nuclear power is also described briefly. The great international effort of research in the LWR design-base and severe accidents, which was, respectively, conducted prior to and following the TMI-2 and Chernobyl accidents is described next. We conclude that with the knowledge gained and the improvements in plant organisation/management and in the training of the staff at the presently-installed nuclear power stations, the LWR plants have achieved very high standards of safety and performance. The Generation 3+LWR power plants, next to be installed, may claim to have reached the goal of assuring the safety of the public to a very large extent. This review is based on the historical developments in LWR safety that occurred primarily in USA, however, they are valid for the rest of the Western World. This review can not do justice to the many fine contributions that have been made over the last fifty years to the cause of LWR safety. We apologize if we have not mentioned them. We also apologize for not providing references to many of the fine investigations, which have contributed towards LWR safety earning the conclusions that we describe just above.

• 전기학회논문지
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• 제59권3호
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• pp.492-498
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• 2010

Since it is almost impossible to train the dispatchers with real power system, the dispatcher training simulator(DTS) is used for the training. Among various components of the DTS, the power system model(PSM) emulates the dynamic behavior of the power system to calculate the frequency and voltage. The frequency is calculated from various parameters such as mechanical power of power plants, load, inertia, and the damping of the power system. In the PSM, the power plants are modeled as differential equations, so the mechanical power of the power plants are calculated by the numerical methods. Conventionally, the fixed step-size algorithm has been used in the PSM, however it has some drawbacks. This paper develops the prototype PSM using the Matlab, and analyzes the problems of the fixed step-size algorithm by comparing the results with those of PSCAD simulation. In order to overcome the limitations, this paper proposes a modified frequency calculation method using the adaptive step-size algorithm. From the simulation using the proposed method, it is verified that the accuracy of frequency calculation increases substantially while the simulation time is not greatly increased.

• KEPCO Journal on Electric Power and Energy
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• 제2권4호
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• pp.525-529
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• 2016

바이오매스 혼소는 신재생 에너지의 비중을 늘리면서 석탄화력발전에서의 $CO_2$ 배출을 저감할 수 있는 단중기적으로 가장 효과적인 방법이다. 본 논문에서는 이 중 기존 화력발전소에 가장 적은 초기투자비로 적용할 수 있는 직접 혼소법에 대하여 주로 고찰을 수행하고, 국내외 현황 및 전망에 대해 기술하였다. 직접 혼소법은 바이오매스 전용 미분기를 사용하여 혼소율을 늘리는 방법과 저 혼소율에서 초기투자비를 최소화하는 기존 석탄 미분기 사용 바이오매스 혼소법으로 나눌 수 있다. 유럽 및 미국에서는 혼소율을 높이기 위해 많은 상용발전소에서 바이오매스 전용 미분기를 사용하여 10~20% 가량의 혼소율(열량 기준)로 운전을 수행하고 있으나, 국내의 경우에는 RPS 대응을 위해 3~5% 가량의 혼소율에서 기존 석탄 미분기를 그대로 사용하여 바이오매스 혼소를 수행하고 있다. 신기후체제가 시작되고 석탄화력발전에서의 $CO_2$ 저감 요구가 점점 더 증대될 것으로 예상되는 바, 향후 바이오매스 고혼소율이 수행될 수 있는 기술적/저책적 방안이 모색되어야 하며, 이 경우 발생할 수 있는 설비에의 악영향을 면밀히 고려한 연료 표준화 및 전처리 기술이 개발되어야 한다.

• 터널과지하공간
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• 제17권1호
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• pp.26-31
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• 2007

우리나라에는 현재 고리, 월성, 영광 등 11기의 원자력 발전소가 운영되면서 전체 전력생산량의 40% 이상을 담당하고 있으며, 2006년까지는 12기가 추가 건설되어 총 23기의 원자력 발전소가 운영되어 국내 총 전력생산량의 절반 이상을 담당하게 될 예정이다. 하지만 이러한 원자력 발전은 필연적으로 인체에 유해한 각종 방사성 폐기물을 생산하게 되므로 이에 대한 처분기술은 대단히 높은 안전율을 고려하여 확보되어야 한다. 한국 원자력연구소의 기초연구에 의하면 국내 실정상 지하 암반내 심층처분이 가장 유리한 시스템인 것으로 보고되고 있으며, 그 중에서도 심도 500 m 이상의 고심도 지하 암반내에 터널을 뚫고 터널 바닥면에 처분공을 일렬로 굴착하여 이 처분공 내에 canister로 밀봉된 방사성폐기물을 유기하는 KBS-3 처분 시스템을 제안하고 있다. 본 연구에서는 KBS-3 처분 시스템을 고려할 경우, 필연적으로 야기되는 고심도 지하에서의 초기응력성분이 처분 시스템에 미치는 영향을 분석하기 위해 수치해석을 실시하였으며 이와 함께 제반 설계정수 중에서 초기응력값이 어떠한 비중을 차지하는지를 살펴보았다.

• 플랜트 저널
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• 제17권2호
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• pp.32-41
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• 2021

최근 미세먼지 등 대기환경 문제가 국가적 이슈로 급부상 하고있는 추세이며 특히 석탄화력발전소에 대한 강도높은 환경규제치가 적용되고 있는 실정이다. 본 연구는 석탄화력발전소 주요 대기오염 배출물질인 황산화물과 먼지 제거를 위한 탈황설비 성능개선 사례에 대해 소개하고 있으며 현재 운영중인 1,000 MW 발전소의 성능개선을 위한 네가지 Case Study를 수행하고 공사를 하였다. 탈황설비 흡수탑 개조를 통해 액기비를 증대시켰으며 산화공기 유량을 증대시켜 기액 반응을 촉진하였다. 또한 가스가스히터 누설률을 개선하여 최종 탈황설비 효율을 향상시켰다. 기존 설비와 조화를 고려한 성능개선 공사를 통해 2023년부터 적용될 규제치(황산화물 25ppm, 먼지 5mg/Sm³)를 만족할 것으로 예상되며 타 화력발전소에 검토 및 적용하는데 참고될 수 있다고 기대된다.

• 한국가스학회지
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• 제15권1호
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• pp.74-80
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• 2011

최근 국내의 많은 에너지 플랜트가 10여년 이상 가동되면서 설비의 장수명화 및 노후설비에 대한 건전성 확보에 대한 요구가 증가하고 있다. 이에 따라 플랜트의 RAM (reliability, availability and maintainability)에 대한 중요도가 높아지고 있다. 플랜트의 RAM을 높이기 위해 RBI (Risk Based Inspection)는 중요한 핵심 기술이다. RBI 기술은 주로 정류 플랜트 설비, 매설배관 설비, 원자력플랜트 설비 등의 에너지 플랜트 분야에서 개발이 진행되어 왔다. 하지만, 기 개발된 RBI 절차는 화력 발전플랜트 등 다른 에너지 플랜트에서의 적용이 어려웠다. 본 연구에서는 에너지 플랜트에서의 최적 예방점검을 위한 일반적인 RBI 표준 절차를 개발하여 보고하였다.