가압 기포 유동층 반응기에서의 Ni계 촉매 CO2 메탄화 특성 연구

다국어 초록 (Multilingual Abstract)

Storing the surplus energy from renewable energy resource is one of the challenges related to intermittent and fluctuating nature of renewable energy electricity production. CO2 methanation is well known reaction that is of interest as a carbon capture and storage (CCS) process and as a renewable energy storage system. CO2 methanation requires a catalyst to be active at relatively low temperatures (250-500℃) and selectivity towards methane. In this study, the catalytic performance test was conducted using a pressurized bubbling fluidized bed reactor (Diameter: 0.025 m and Height: 0.35 m) with Ni/α/γ-Al2O3 (Ni 70% and Ni 40%) catalyst. The range of the reaction conditions were H2/CO2 mole ratio range of 4.0-6.0, temperature of 240-420℃, pressure of 1-9bar, and gas velocity (Uo/Umf) of 1-5. As the H2/CO2 mole ratio, temperature, CO2 conversion increases at the experimental temperature range. However, CO2 conversion decreases with increasing gas velocity due to poor mixing characteristics in the fluidized bed. The maximum CO2 conversion of O-Ni/α-Al2O3 of 99.6% was obtained with the operating condition as follows; H2/CO2 ratio of 5, temperature of 400℃, pressure of 3bar, and Uo/Umf of 3. And the maximum CO2 conversion of C-Ni/γ-Al2O3 was confirmed with the operating condition as follows; H2/CO2 ratio of 5, temperature of 280℃, pressure of 1bar, and Uo/Umf of 3. The long term tests for both show that the CO2 conversion was kept constant for 30 hours.

목차 (Table of Contents)

• Ⅰ. 서론 1
• Ⅱ. 이론적 배경 4
• 2.1. Power to gas 4
• 2.2. CO2 메탄화 8
• 2.2.1. 메탄화 반응 메커니즘 10
• 2.2.2. 메탄화 반응기의 종류 12
• 2.2.3. 메탄화 촉매 15
• 2.3. 이론식 17
• 2.3.1. CO2 전환율, CH4 선택도, CH4 수율 식 17
• Ⅲ. 실험 18
• 3.1. 실험 재료 18
• 3.1.1. 촉매 18
• 3.1.2. 층물질 19
• 3.2. 실험 방법 23
• 3.2.1. 반응기 23
• 3.2.2. 실험 방법 25
• Ⅳ. 결과 및 고찰 27
• 4.1. 온도에 따른 반응 특성 27
• 4.2. 압력에 따른 반응 특성 30
• 4.3. H2/CO2 ratio에 따른 반응 특성 33
• 4.4. 유속에 따른 반응 특성 36
• 4.5. 장기 운전에 따른 특성 40
• Ⅴ. 결론 45
• Abstract 47
• 참고문헌 49