Effect of temperature on safety and stability of gas hydrate during coal mine gas storage and transportation

In this study, the hydrate dissociation experiment is conducted by using visual hydrate formation and dissociation experimental device for two kinds of CMG samples under four different temperatures. The thermal stimulation method (above the equilibrium temperature) is applied for hydrate dissociation. Based on the experimental data, it is found that the pressure curve during gas hydrate dissociation is mainly composed of three stages, including rapid dissociation, slow dissociation, and stable stages. Temperature has a significant effect on the average dissociation rate for the gas system, where a higher temperature is related to greater average dissociation rate. The maximum average dissociation rate is determined to be 4.34 ∙ 10−3 mol/min (System II-4). The mole number of methane increases obviously with the increase of temperature, while nitrogen and oxygen change slightly. It demonstrates that methane hydrate has higher risk in storage and transportation.
Source: Safety Science - Category: Occupational Health Source Type: research