A Study of Methane Hydrate Combustion Phenomenon Using The Porous Cylindrical Burner

• Main Authors: Wu, Fang-Hsien, Chen, Guan-Bang, Li, Yueh-Heng, Chao, Yei-Chin
• Other Authors: Department of Aeronautics and Astronautics
• Format: Conference Object
• Language: English
• Published: 2015
• Subjects: methane hydrate; seeding method; porosity; self-preservation effect; porous cylindrical burner; Ice; Methane hydrate; permafrost
• Online Access: http://ir.lib.ncku.edu.tw/handle/987654321/166309; http://ir.lib.ncku.edu.tw/bitstream/987654321/166309/2/3011004000-000002_2.pdf; http://ir.lib.ncku.edu.tw/bitstream/987654321/166309/1/3011004000-000002_1.pdf

There is a large amount of methane hydrate reserves in the permafrost, the mainland coast and the deep waters all over the world. The global methane hydrate contains about 2.5x1015 m3 methane gas. Methane hydrate refers to methane molecules are surrounded by water molecules with crystalline structure and it is formed as an ice-like solid structure (SI structure). Methane hydrate is usually expressed by the chemical formula of CH4 ∙nH2O(s) ( CH4(g) + nH2O(s → l) → CH4 ∙nH2O(s)). N is the hydrate number and its theoretical value is 5.73. The literature shows that approximate 160 m3 methane will be released from the decomposition of 1 m3 methane hydrate. The literature on the use of methane hydrate for energy purpose and even the research concerning direct combustion of methane hydrate is rather limited. According to direct combustion of methane hydrate will extinct due to self-preservation effect and it is unable to get complete combustion of methane hydrate. It is obvious that how to overcome the selfpreservation is a very important issue in the combustion process. The flame phenomenon and pattern of methane hydrate and how to overcome the problem of flame extinction are still not clear. Therefore, we have designed a novel porous cylindrical burner to maintain stable combustion of methane hydrate and the flame patterns and phenomenon are investigated experimentally. It effectively solves the burning issues and sustains a stable flame. The flame radius and methane release rate can be determined from the experiments. In addition, the numerical simulation will be performed to investigate the effects of water on methane/air diffusion flame in the porous cylindrical burner.