EXPERIMENTAL STUDY OF NATURAL GAS HYDRATE DISSOCIATION IN POROUS MEDIA WITH A 2D EXPERIMENTAL SYSTEM BY CONTINUOUS THERMAL STIMULATION AND DEPRESSURIZATION

Experimental study on NGH dissociation was carried out with a special designed 2D experimental system. The experiment was performed by injecting hot brine and decreasing pressure (thermal stimulation plus depressurization). The change of temperature, gas production rate, water production rate and energy efficiency were analyzed during the NGH dissociation. Experimental results demonstrate that the injecting hot brine water does not bring in the full dissociation of all of NGH in the model. So it is necessary to decrease pressure. Then the dissociated gas can be obviously divided into thermal dissociated gas and depressurized dissociation gas. Water production rate of the thermal stimulation is obviously greater than that of depressurization. Thermal stimulation together with depressurization can achieve higher energy efficiency and therefore is a better method for NGH dissociation and production.