Qingping Li

Experimental simulation of gas hydrate decomposition in porous sediment

Gas hydrate decomposition in sediments involves complicated multiphase flow and heat and mass transfer processes because of heat absorption by solid hydrates. Factors affecting gas hydrate decomposition in sediments include sediment type, mineral composition, pore size distribution, particle size, pore water composition, hydrate saturation distribution, initial formation pressure and temperature and cement characteristics. In this paper, experimental simulations of gas hydrate decomposition are carried out on an artificial core to investigate the effects of initial pressure and temperature, particle size and pore size. The experiments show that the characteristics of gas hydrate decomposition in sediments differ completely from those in a pure water system. The decomposition rate of hydrate sediments increases with the initial pressure increasing and decreasing temperatures. Furthermore, the decomposition rate of hydrate sediments decreases with decreasing particle size and increasing pore size.