http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
물분사 폐열회수 보일러의 효용성 검증을 위한 기초 연구
서준선(Jun-Sun Seo),이창언(Chang-Eon Lee),박태준(Tae-joon Park),문석수(Seok-su Moon),김형래(Hyoung-Rae Kim),강영각(Young-Kag Kang) 대한기계학회 2021 大韓機械學會論文集B Vol.45 No.8
본 논문에서는 개발 중인 물분사 폐열회수 보일러(HR-B/WS)의 효용성을 검증하는 예비 결과를 소개한다. HR-B/WS는 폐열회수 과정에서 발생하는 고온 응축수를 유입 공기에 재순환 분사하는 보일러로 폐열 회수량을 증가시키고 동시에 공기비에 무관하게 화염 온도를 낮추어 NOx 생성을 억제시키고자 고안된 것이다. HR-B/WS는 동일 환수온도 조건의 컨덴싱 보일러에 비해 NOx, CO 농도는 약 50% 정도저감시키나 효율 증가는 2~3%로 예상보다 크지 않음을 확인하였다. 그 원인을 HR-B/WS의 열·물질 정산 분석을 통해 파악하고 효율 개선을 위한 폐열회수 시스템의 설계 방안을 확인하였다. This paper introduces a preliminary study to validate the efficacy of a heat recovery boiler with water spray (HR-B/WS) that is currently under development. The HR-B/WS, where high temperature water condensed in the system is sprayed onto the inlet airstream, is designed to increase the recovery of waste heat and reduce NOx formation by lowering the flame temperature irrespective of the air ratio. Compared to the basic condensing boiler with the same return water temperature, HR-B/WS reduces the NOx and CO emission by approximately 50%. However, the rise in the efficiency was estimated at 2~3%, which was less than expected. This study identified its causes by analyzing the heat and mass balances based on the preliminary results and confirmed the design points of the heat recovery system aimed at improving the efficiency.
난방용 보일러에서 NG-H₂ 혼소율에 따른 열 및 공해 성능의 검토
서준선(JUNSUN SEO),김영직(YOUNG-JIC KIM),박준규(JUNKYU PARK),이창언(CHANG-EON LEE) 한국수소및신에너지학회 2021 한국수소 및 신에너지학회논문집 Vol.32 No.6
Hydrogen is evaluated as one of the new energy sources that can overcome the limitations and pollution problems of conventional fossil fuels. Although hydrogen is CO₂-free, attention is required in NOx emission and flame stability in order to use hydrogen in existing gas fuel system. However, use of electric grids is an unrealistic strategy for decarbonization for residential and commercial heating. Instead, use of H₂ that utilizes city gas grid is suggested as a reasonable alternative in terms of compatibility with existing systems, economic feasibility, and accessibility. In this study, the thermal efficiency and NOx performance of the boiler according to the H₂ mixture ratio and vapor humidified ratio are reviewed for a humidified NG-H₂ boiler that vapor humidity to combustion air. Mixed fuel with H₂ (20%) is almost similar to NG in terms of efficiency, flame temperature, and pollution performance. Thus, it is expected to be directly compatible with the existing NG system. If the exhaust temperature of the H₂ boiler is lowered to around 60℃ at a humidified ratio of 15-20%, the NOx emission concentration can be suppressed to about 5-10 ppm. The level of efficiency reaches 87% of the rated load efficiency, which is equivalent to the highest grade achievable.
Enhancement of PLED lifetime using thin film passivation with amorphous Mg-Zn-F
강병호,김도옥,김재현,서준선,강신원,김학린,이형락,Dae-Hyuk Kwon 한국정보디스플레이학회 2010 Journal of information display Vol.11 No.1
In this study, a new thin films passivation technique using Zn with high electronegativity and MgF2, a fluorine material with better optical transmittance than the sealing film materials that have thus far been reported was proposed. Targets with various ratios of MgF2 to Zn (5:5, 4:6 and 3:7) were fabricated to control the amount of Zn in the passivation films. The Mg-Zn-F films were deposited onto the substrates and Zn was located in the gap between the lattices of MgF2 without chemical metathesis in the Mg-Zn-F films. The thickness and optical transmittance of the deposited passivation films were approximately 200 nm and 80%,respectively. It was confirmed via electron dispersive spectroscopy (EDS) analysis that the Zn content of the film that was sputtered using a 4:6 ratio target was 9.84 wt%. The Zn contents of the films made from the 5:5 and 3:7 ratio targets were 2.07 and 5.01 wt%, respectively. The water vapor transmission rate (WVTR) was determined to be 38℃, RH 90-100%. The WVTR of the Mg-Zn-F film that was deposited with a 4:6 ratio target nearly reached the limit of the equipment, 1×10-3 g/m2·day. As the Zn portion increased, the packing density also increased, and it was found that the passivation films effectively prevented the permeation by either oxygen or water vapor. To measure the characteristics of gas barrier, the film was applied to the emitting device to evaluate their lifetime. The lifetime of the applied device with passivation was increased to 25 times that of the PLED device,which was non-passivated.