• 에너지공학
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• 제23권4호
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• pp.49-55
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• 2014

석탄화력 발전소 보일러의 부식 메카니즘에 대한 실증적 고찰을 위하여 500MW 표준화력 발전소 보일러에 대한 보일러 튜브의 두께측정 및 수치해석을 병행하여 분석을 시행하였다. 그 결과 접선연소방식의 보일러 수냉벽 튜브의 부식에 가장 핵심적인 영향을 미치는 메카니즘은 퇴적된 미연탄소분에 포함된 유황분에 의한 부식이었으며, 두 번째 요소는 보일러 내부에서 국부적인 환원성 분위기가 생성되는 위치에서의 $H_2S$ 가스에 의한 부식으로 나타났다. 이와 같은 수냉벽튜브 부식을 완화시키기 위해서는 보일러의 다단연소 운전을 감소시키는 것이 필요하며, 미연분 감소를 위한 엄격한 미분도 관리 및 부식 취약부위에 대한 내부식 코팅보강 작업이 필요하다.

• 환경영향평가
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• 제24권5호
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• pp.472-486
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• 2015

국내 석탄화력발전소에서는 매년 800만 톤 이상의 석탄회가 배출되고 있으며, 이에 대한 최종적인 처리는 현재 약 70% 수준의 재활용, 그리고 해안 회처리장을 통해 매립 처리하고 있다. 그러나 실질적으로 개별 발전시설의 회처리장마다 수년 내에 만지(포화) 시기의 도래가 예상되며, 석탄회처리장 건설로 인한 환경영향에 대한 우려로 신규 확보도 어려운 상황이다. 향후 "제7차 전력수급기본계획"을 반영하여 추가적으로 건설될 석탄화력 발전시설을 고려했을 때(2020년 기준 1,000만 톤 배출 예상), 회처리장의 신규조성이 불가피하다. 그러나 회처리장 조성으로 인해 기존의 양호한 자연해안지역이 훼손되는 문제가 우려될 수 있다. 따라서 본 연구에서는 석탄회로 인한 환경영향을 최소화하기 위해, 근본적으로 추가적인 석탄화력 발전시설과 회처리장의 건설을 줄여나가고 더불어 배출된 석탄회의 유효이용 및 재활용 활성화를 위한 정책적 방안을 제시하고자 하였다.

• 에너지공학
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• 제26권4호
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• pp.45-56
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• 2017

Coal power plants produce electricity for the nation's power grid, but they also produce more hazardous air emissions than any other industrial pollution sources. The quantity is staggering, over 386,000 tons of 84 separate hazardous air pollutants spew from over 400 plants in 46 states. In South Korea also, annual coal ash generation from coal-fired power plants were about 6 million tons in 2015. Pollutants containing particulate matter 10, 2.5 (PM10, PM2.5), heavy metals and dioxins from coal-fired power plant. The emissions threaten the health of people who live near these power plants, as well as those who live hundreds of miles away. These pollutants that have long-term impacts on the environment because they accumulate in soil, water and animals. The present study is to investigate the physical and chemical characteristics of coal-fired power plant fly ash and bottom ash contains particulate matter, whose particulate sizes are lower than $PM_{10}$ and $PM_{2.5}$ and heavy metals. There are wide commercial technologies were available for monitoring the PM 2.5 and ultra-fine particles, among those carbonation technology is a good tool for stabilizing the alkaline waste materials. We collected the coal ash samples from different coal power plants and the chemical composition of coal fly ash was characterized by XRF. In the present laboratory research approach reveals that potential application of carbonation technology for particulate matter $PM_{10}$, $PM_{2.5}$ and stabilization of heavy metals. The significance of this emerging carbonation technology was improving the chemical and physical properties of fly ash and bottom ash samples can facilitate wide re use in construction applications.

• KEPCO Journal on Electric Power and Energy
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• 제1권1호
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• pp.121-125
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• 2015

Distribution of rare earth metals (REMs) and rare valuable metals (RVMs) contents in coal ashes (fly ash, bottom ash, and pond ash) and leachate from 11 coal-fired power plants in Korea were investigated. Coal ashes and leachates were found to contain important REMs and RVMs such as Yttrium (Y) and Neodymium (Nd), which was in the range of 23~75 mg/kg. However, it still requires developing effective recovery and separation methods in order to utilize REMs and RVMs in ash and leachate. Recovery of valuable elements (Y and Nd) from various and extensive ash sources (8.21 million tons/year in 2013) can provide the existing power plants with additional profit; therefore, it can significantly improve economics of the power plants.

• 환경영향평가
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• 제9권1호
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• pp.1-11
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• 2000

An environmental geochemical survey of heavy metal distribution in marine surface sediments around the ocean of Samcheonpo coal-fired power plant was conducted to investigate the possibility of coal-ash leakage from ash pond and the associated heavy metal pollution in sedimental deposits due to the operation of the coal-fired power plant. The X-Ray Diffractometry (XRD) analysis showed that the main leakage point of coal-ash was limited to a single site of the first ash pond. It also appeared that the amounts of organic carbon and metal elements were positively correlated to the grain size distribution, and that Co, Cr, Cu, Fe, Ni, and Zn were bounded to organic ligands. However, the distributions of Cd, Hg, and Mn did not have any significant correlation with the sediment grain size and organic matters. In particular, the distribution of Cd appeared to be affected by the concentration of the carbonate materials in the study area.

• 조명전기설비학회논문지
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• 제26권8호
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• pp.88-95
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• 2012

When controling combustion air flow in coal fired power plant the furnace safety must be considered first prior to plant efficiency. therefore it is very important to set air flow demand exactly for safe operation and maintenance. This paper analyze air flow control loop in power plant and introduce the method to improve dynamic response time. Simulation result shows this scheme is adoptable and provide better performance.

• 전기학회논문지
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• 제57권12호
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• pp.2285-2290
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• 2008

Even though efficiency of coal-fired power plant is proportional to operating temperature, increasement of operating temperature is limited by a technological level of each power plant component. It is an alternative plan to increase operating pressure up to ultra super critical point for efficiency enhancement. It is difficult to control process of power plant in ultra super critical point because that point has highly nonlinear characteristics. In this paper, new control logic, Unit Response Optimizer Controller(URO Controller) which is based on Fuzzy logic and Model Predictive Controller, is introduced for better performance. Then its performance is tested and analyzed with design guideline.

• 한국산업보건학회지
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• 제33권4호
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• pp.464-470
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• 2023

Objectives: This study evaluated occupational exposures to noise and heat stress during routine non-outage works in three coal-fired power plants in the Republic of Korea. Methods: The data were collected during the summer of 2020. Full shift noise exposure of 52 workers were measured using noise dosimeters. Heat stress of 16 worksites were measured for 70 minutes using wet-bulb globe temperature monitors. Results: The noise dosimetry results revealed time-weighted averages that ranged from 47.5 to 88.9 dBA. 2 out of 52 noise measurements exceeded 85 dBA. Based on the arithmetic mean, the coal service group showed the highest level at 80.2 dBA by job tasks. Noise exposures exceeding 85 dBA were measured in the coal service and plant operator group. Heat stress index measurements ranged from 20.3℃ to 37.2℃. 1 out of 9 indices measured in coal facilities and 4 out of 7 indices measured in boiler house exceeded 1 hour TWA during moderate work. Heat stress indices measured from boiler houses were significantly higher than those measured from coal equipment. Conclusions: The results show that overexposure to noise and heat stress may be encountered during routine non-outage work activities in coal-fired power plants. Appropriate actions should be taken to reduce future health outcome from occupational exposure to noise and heat stress in the industry.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.1817-1818
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• 2008

Even though efficiency of coal-fired power plant is proportional to operating temperature, increasement of operating temperature is limited by a technological level of each power plant components. It is an alternative plan to increase operating pressure up to ultra super critical point for efficiency enhancement. It is difficult to control in that pressure within safety guideline that many unexpected phenomena are happen because that region is highly nonlinear region. In this paper, Advanced process control algorithm, ARX and Fuzzifier, is introduced. Then power plant control logics applied Unit Step Optimizer, which is combination of ARX and Fuzzifier are proposed. Its performance is tested and analyzed with design guide line.

• Journal of Information Processing Systems
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• 제15권1호
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• pp.189-202
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• 2019

During thermal power coal-fired boiler operation, it is very important to detect the pulverized coal concentration in the air pipeline for the boiler combustion stability and economic security. Because the current measurement methods used by power plants are often involved with large measurement errors and unable to monitor the pulverized coal concentration in real-time, a new method is needed. In this paper, a new method based on microwave circular waveguide is presented. High Frequency Electromagnetic Simulation (HFSS) software was used to construct a simulation model for measuring pulverized coal concentration in power plant pipeline. Theoretical analysis and simulation experiments were done to find the effective microwave emission frequency, installation angle, the type of antenna probe, antenna installation distance and other important parameters. Finally, field experiment in Jilin Thermal Power Plant proved that with selected parameters, the measuring device accurately reflected the changes in the concentration of pulverized coal.