정적연소챔버(CVCC)를 활용한 선박용 바이오연료 혼합유의 연소 특성에 관한 기초 연구

다국어 초록 (Multilingual Abstract)

In response to the tightening environmental regulations by the International Maritime Organization(IMO), the introduction of alternative marine fuels has become an urgent challenge for the shipping industry. This study aimed to comprehensively evaluate the combustion characteristics and operational stability of two representative biofuels - biodiesel(BD) and bio-heavy oil(BHO) - when blended with conventional marine fuels, namely marine gas oil(MGO) and very low sulfur fuel oil(VLSFO). Combustion experiments were conducted on 16 types of blended fuels using a Constant Volume Combustion Chamber(CVCC). The main analysis parameters included Ignition Delay(ID), Maximum Rate of Heat Release(MaxROHR), Position of Maximum ROHR(PMR), and Accumulated Rate of Heat Release(AR), which were used to quantitatively compare the ignition quality, combustion intensity, and combustion efficiency of each fuel. Additionally, long-term storage stability tests were performed under ambient (24℃) and low-temperature (1℃) conditions to experimentally investigate the effects of post-storage remixing methods on combustion stability. The results showed that biodiesel acted as an effective combustion improver, shortening ignition delay across all base fuels due to its superior ignition quality. When blended with VLSFO, which has inherently poor ignition properties, biodiesel reduced ignition delay by up to 25.1% and increased MaxROHR by 10.3%, demonstrating its strong potential to enhance the combustion performance of low-grade residual fuels. In contrast, bio-heavy oil exhibited a significant decline in combustion intensity due to its high viscosity and poor atomization characteristics. When blended with VLSFO, it showed the lowest combustion efficiency caused by chemical incompatibility. Storage stability tests revealed that biodiesel blends were prone to oxidation at ambient temperature and wax crystallization or phase separation under low-temperature conditions simulating Arctic routes, leading to physical inhomogeneity of the fuel. Particularly, unremixed fuels after cold storage showed large variations in ignition timing between cycles, causing severe combustion instability. However, mechanical stirring successfully restored combustion stability by rehomogenizing the fuel mixture. This finding highlights the necessity of implementing fuel homogenization systems for the stable operation of biofuel blends in cold environments. In conclusion, the practical application of marine biofuels requires an integrated, system-level approach that goes beyond mere fuel substitution. Factors such as fuel composition, blend compatibility, storage stability, and supply conditions must be holistically considered. Biodiesel presents a realistic and effective option for improving VLSFO combustion performance, whereas bio-heavy oil demands further technological advancements for safe utilization. The outcomes of this study are expected to provide essential scientific and engineering insights for establishing future quality standards and safe operational guidelines for eco-friendly marine fuels. Keywords: Biodiesel, Bio-heavy oil, CVCC, Combustion characteristics, Marine alternative fuels, Low-temperature Storage Stability

목차 (Table of Contents)

• List of Table· ⅲ
• List of Figures ⅳ
• Nomenclature and Abbreviation ⅴ
• Abstract ⅶ
• 1. 서 론· 1
• 1.1 연구 배경 1
• 1.2 선행 연구 동향 3
• 1.3 연구 목표 4
• 2. 이론적 배경 6
• 2.1 바이오 연료의 개요 6
• 2.1.1 바이오디젤 6
• 2.1.2 바이오중유 6
• 2.2 제조 공정 및 기술 동향 7
• 2.2.1 바이오디젤 원료 및 제조 공정· 7
• 2.2.2 바이오중유 원료 및 제조 공정· 9
• 3. 연구 방법 11
• 3.1 실험 구성 및 조건 11
• 3.2 실험 장비· 20
• 3.2.1 FIA-100/FCA 연소 분석 장비 20
• 3.2.2 부속 장비 22
• 3.3 장비의 신뢰성 검증 24
• 3.4 주요 연소 특성 정의 29
• 4. 연구 결과 및 논의· 34
• 4.1 연료 저장 안정성 평가 결과 34
• 4.2 바이오연료 혼합유의 연소 특성 분석 41
• 4.2.1 선박용디젤 + 바이오디젤 41
• 4.2.2 선박용디젤 + 바이오중유 43
• 4.2.3 저유황잔사유 + 바이오디젤 45
• 4.2.4 저유황잔사유 + 바이오중유 47
• 4.3 저온 보관 및 재혼합 방식에 따른 연소 특성 분석 52
• 4.3.1 저온 환경에서 물리적 변화에 대한 이론적 고찰 52
• 4.3.2 재혼합 방식에 따른 연소 특성 분석· 52
• 5. 결 론 58
• 참고문헌· 60
• 국문초록· 65