Discussion of Environmental Safety Factors in Subsea Natural Gas Hydrate Exploitation

The demand towards natural gas continues to grow in China and large-scale exploitation of subsea natural gas hydrate is inevitable; however, environmental protection in conjunction with methane hydrate production poses challenges. At present, the exploitation of subsea gas hydrate is still in its initial stages, and no commonly accepted method of exploitation has been developed yet. The main reason for production delays is that the exploitation of gas hydrate is likely to cause instantaneous release of gas hydrate and lead to serious environmental disasters. This paper analyzes the exploitation principle of gas hydrate, investigates exploitation practices, and emphasizes that the most important physical process in gas hydrate exploitation is gasification. Gasification requires a large amount of heat, whereas, heat transmission in formation is slow. Therefore, the exploitation of gas hydrate should be conducted at a moderate pace on the premise of maintaining a manageable but not catastrophic release of gas hydrate.