• 대한환경공학회지
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• 제27권3호
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• pp.286-292
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• 2005

본 연구는 향후 산업적으로 질소산화물 규제가 중요한 문제로 대두될 만한 산업용 보일러를 대상으로 수행하였다. 일반적으로 SNCR 방법의 산업용 보일러로의 적용은 혼합을 위한 충분한 체류시간을 제공하지 못한다는 점에서 적합하지 않은 것으로 알려져 있다. 본 연구의 목적은 SNCR 장치의 산업용 보일러 적용가능성을 조사하기 위한 것이다. 구체적으로 연료로 중유를 사용하는 시간당 스팀 발생량 40톤 규모의 산업용 보일러를 연구 대상으로 하였다. 사업용 보일러의 수치 해석을 위한 3-D 직교좌표계 프로그램에는 난류 유동, 난류 연소반응, NOx의 생성과 환원제와의 반응을 통한 소멸반응 등을 포함하고 있다. 또한 개발된 코드에는 Lagrangian 방법에 의한 입자궤적 프로그램이 포함되어 있고, 주입구에서 접선방향으로의 선회효과를 계산에 의해 고려하였다. 선회버너 효과를 고려한 결과 단화염이 생성되었으며 NOx 환원반응에 적합한 온도 영역의 증가로 인해 NOx 제거효율도 향상되었다. 실험결과와의 비교를 통하여 프로그램을 검증하였으며, 계산결과 혼합용 공기 주입을 통한 환원제와의 혼합 향상을 통해서 SNCR 방법의 산업용 보일러 적용가능성을 확인하였다.

• 설비공학논문집
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• 제21권3호
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• pp.157-166
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• 2009

The pulverized coal combustion behavior in the coal fired utility boiler has been investigated with the CFD and process analysis techniques. The used commercial software were CFX and PROATES, and these were coupled each other to get more reliable boundary condition set-up, resulting in more reliable solution. For two cases which were the actual operation condition of A power plant, the calculated values from the coupled CFD and process analysis for thermal energy system were compared with the plant data, and the good agreements were obtained for Case 1 and 2. The calculated temperature distributions on the surface of heat exchangers were compared with the plant data for the steam temperatures across heat exchangers, and these explained the actual operating situation very well. The temperature deviation across the final superheater tube, which was believed to be the main cause of the frequent tube failure, were also explained very well with the calculated distributions of gas temperature and radiation on the plane of the final superheater.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2008년도 춘계학술대회 논문집
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• pp.415-418
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• 2008

This paper presents an innovative prototype of a new conceptual electromagnetic induction-based fluid beating appliance using voltage-fed type scries capacitor-compensated load resonant high-frequency IGBT inverter with a phase-shifted PWM and a power factor correction schemes. Its operating characteristics in steady-state are illustrated including unique features and evaluated on the basis of its computer simulation and experimental results of 10kw breadboard appliance for hot water producer and superheated steamer. The promising cost effective inverter-fed boiler appliances for electromagnetic induction-heated type fluid-heating in the pipeline systems are proposed for induction-heated boiler, super heat steamer, high temperature water producer, hot gas producer and metal catalyst heating for exhaust gas cleaning in engine, which are more suitable and acceptable for industrial, chemical, and consumer energy utilization for household and business from a practical point of view.

• 청정기술
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• 제5권2호
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• pp.53-61
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• 1999

대형 산업용 환경폐기물 처리 및 열병합 플랜트의 연소 및 소각 공정 후 발생하는 배기가스의 폐열회수장치 설계 방법을 제시하였다. 본 연구는 폐열회수장치의 기본 설계 개념을 폐열회수를 위한 보일러와 폐열을 이용한 증기 동력 사이클로 구성되는 것으로 가정하였고, 폐열회수장치에 필요한 각 구성요소들에 대한 모델링 기법과 그에 따른 설계 기준 및 설계 개념을 기술하였다. 또한 본 설계방법을 이용하여, 동일한 배기가스 조건에 대해, 폐열회수 보일러의 작동 압력 및 폐열회수 열교환기 설계에 따라 폐열회수장치의 열성능이 어떻게 변화되는지를 검토하였다.

• Nuclear Engineering and Technology
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• 제19권3호
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• pp.198-204
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• 1987

발전소 과도현상과 비냉각재 상실사고를 모의할 수 있는 가압경수로발전소 모의코드 MCSIM을 개발하였다. 원자로 냉각재계통은 에너지 방정식과 운동량 방정식을 분리 취급하면서 Drift Flux 2상 유동모델, 적분 운동량 방정식 등을 사용하여 모델링하였다. 증기발생기의 모사는 Pot Boiler 모델을 사용하였고, 2차계통을 위해서는 분리 취급된 정상상태 에너지 방정식과 운동량방정식을 핵출력 계산을 위해서는 점 동특성 방정식을 사용하였다. 현재의 코드성능을 시험하기 위해 완전 냉각재 유동상실사고와 제어봉 집합체 인출 사고를 계산하여 그 결과를 원자력 5/6호기 최종 안전 보고서의 결과와 비교하였다.

• 한국항해항만학회지
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• 제48권2호
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• pp.125-136
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• 2024

This research presents an innovative integrated ethanol solid oxide fuel cell (SOFC) system designed for applications in marine vessels. The system incorporates an exhaust gas heat recovery mechanism. The high-temperature exhaust gas produced by the SOFC is efficiently recovered through a sequential process involving a gas turbine (GT), a regenerative system, steam Rankine cycles, and a waste heat boiler (WHB). A comprehensive thermodynamic analysis of this integrated SOFC-GT-SRC-WHB system was performed. A simulation of this proposed system was conducted using Aspen Hysys V12.1, and a genetic algorithm was employed to optimize the system parameters. Thermodynamic equations based on the first and second laws of thermodynamics were utilized to assess the system's performance. Additionally, the exergy destruction within the crucial system components was examined. The system is projected to achieve an energy efficiency of 58.44% and an exergy efficiency of 29.43%. Notably, the integrated high-temperature exhaust gas recovery systems contribute significantly, generating 1129.1 kW, which accounts for 22.9% of the total power generated. Furthermore, the waste heat boiler was designed to produce 900.8 kg/h of superheated vapor at 170 ℃ and 405 kP a, serving various onboard ship purposes, such as heating fuel oil and accommodations for seafarers and equipment.

• 한국산업보건학회지
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• 제21권3호
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• pp.123-127
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• 2011

Objectives: The purpose of this study was to investigate the status of asbestos-containing materials (ACMs) used on ships and to consider measures for preventing worker exposure to asbestos fibers. Methods: A total of 17 ships including 16 ships under repair and a ship under construction at shipyards in Korea were investigated. Bulk samples were collected from suspected ACMs on engine exhaust pipes, boiler steam pipes, generator exhaust pipes, and etc. in ships in order to identify the presence of ACMs. Types and contents of asbestos were determined using polarized light microscopy (PLM). Results: ACMs were found from 14 ships out of 17 ships investigated. Only chrysotile asbestos was found from all samples. ACMs were mainly found from samples collected at the exhaust pipes of the engine, generator and incinerator, and boiler steam pipes where exhaust gases or steam of high temperature pass through. In most cases, types of ACMs were asbestos-containing fabrics such as asbestos tape. Friable ACMs were also found in some cases. Use of ACMs on ships was relevant to built time and owner of the ships rather than type and tonnage of the ships. Conclusions: ACMs were found from most ships built prior to 2000s. Therefore, measures for preventing asbestos-related diseases such as preparation of asbestos map on the ship and installation of warning signs, hazard communication with workers (ship-repairing workers, engine room workers and etc.), and follow-up for worker's health management are needed.

• 한국압력기기공학회 논문집
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• 제12권1호
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• pp.101-106
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• 2016

NSSS (Nuclear Steam Supply System) and BOP (Balance of Plant) design works for PGSFR (Prototype Gen-IV Sodium Fast Reactor) have been conducted in Korea. NSSS major components, e.g. reactor vessel, steam generator and secondary sodium main pipes, are designed according to the rule of ASME boiler and pressure vessel code division 5, in which DBA (Design by Analysis) methods are used in the stress assessments. However, there is little discussions about detail rules for BOP piping design. In this paper, the detail methodologies of BOP piping stress assessment are discussed including safety systems and non-safety system pipings. It is confirmed that KEPIC MGE(ASME B31.1) and ASME BPV code division 5 HCB-3600 can be used in stress assessments of non-safety pipes and class B pipes, respectively. However, class A pipe design according to ASME BPV code division 5 HBB-3200 has many difficulties applying to PGSFR BOP design. Finally, future development plan for class A pipe stress assessment method is proposed in this paper.

• 대한기계학회논문집B
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• 제25권11호
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• pp.1616-1623
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• 2001

A basic experimental study has been carried out to find out the design parameters of fuel 2-staging atomizers in order to reduce nitrogen oxides(NOx) rate emitted from the steam boilers used the liquid fuel. The heavy fuel oil(B-Coil) and fuel 2-staging Y-jet twin-fluid atomizers were adopted in this study. The results of this paper were obtained from the real as well as the model scale atomizers. In the case of model atomizers test, NOx reduction rate was strongly dependent on the staged fuel rate, but it was weakly dependent on the injection hole arrangement and air swirl conditions. The real scale atomizers was designed and manufactured on the base of these test results, and those was mounted and operated in the real boiler generates 185 ton steam per an hour. The reduction rate of the model and real plant was reached 10∼30% of base NOx by atomizers. but dust was sharply increased in the low O$_2$combustion region of the real plant.

• 한국해양공학회지
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• 제13권2호통권32호
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• pp.90-98
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• 1999

Boiler high-temperature pipelines such as main steam pipe, header and steam drum in fossil power plants are degraded by creep damage due to severe operationg conditions like high temperature and high pressure for an extended period time. Such material degradation lead to various component faliures causing serious accidents at the plant. Conventional measurement techniques such as replica method, electric resistance method, and hardness test method have such disadvantages as complex preparation and measurement procedures, too many control parameters, and therefore, low practicality and they were applied only to component surfaces with good accessibility. In this study, both artificial creep degradation test using life prediction formula and frequency analysis by ultrasonic tests for their preparing creep degraded specimens have been carried out for the purpose of nondestructive evaluation for creep damage which can occur in high-temperature pipelline of fossil power plant. As a result of ultrasonic tests for crept specimens, we confirmed that the high frequency side spectra decrease and central frequency components shift to low frequency bans, and bandwiths decrease as increasing creep damage in backwall echoes.