OS6C-6：EXPERIMENTS AND INSIGHTS OF GAS HYDRATE DISSOCIATION IN WATER/OIL DISPERSED SYSTEMS

Jun CHEN, Changyu SUN *, Ning REN, Menglei JIA, Kele YAN, Yining LV, Guangjin CHEN *,
State Key Laboratory of Heavy Oil Processing, China University of Petroleum, CHINA
   
    Gas hydrate dissociation in water/oil dispersed system especially in water/oil emulsions is an important process in the transportation of gas and oil via using hydrate slurry transportation technology. An understanding of the mechanism for gas hydrates dissociation in water/oil dispersed systems is of significance for both the solution to the blockage of hydrates and the application of the hydrate slurry transportation technology.
   
    Three apparatuses are used to investigate the process of gas hydrate dissociation in w/o dispersed systems: an autoclave with PVM (particle video microscope) and FBRM (focused beam reflectance measurement) probes, a high pressure sapphire cell with air bath and a flow loop with water bath. The experiments were focused on the morphologies of the gas hydrate during its dissociation. PVM pictures combined with FBRM mean chord length and chord length distributions of the chord lengths are also analyzed. It found that the release of large numbers of gas bubbles and agglomeration often appear during gas hydrate dissociation in water/oil dispersed systems. Based on the experimental results, a new mechanism for gas hydrates dissociation including diffusion, dissolution of gas and hydrate agglomeration was proposed to describe the process of gas hydrate dissociation in water/oil dispersed systems. The proposed mechanism can effectively explain the gas bubble and agglomeration phenomenon appeared during gas hydrate dissociation. The mechanism can help to understand gas hydrate dissociation and to establish gas hydrate dissociation model in water in oil dispersed systems well, which will help to solve hydrate problems in gas and oil transportation.