| As the oil and gas industry move towards the deeper sea gradually,the natural gas hydrate "ice block" issue in oil and gas multiphase pipeline has to be settled urgently in nowadays.The natural gas hydrate slurry transportation technology,as the key in the deep-water flow assurance of hydrate risk control,has become a focal point in the hydrate research field.Among the other researches,research on the characteristics of the natural gas hydrate slurry multiphase flow in the pipeline system is the key to prevent natural gas hydrate to form "ice block" and carry out hydrate slurry transportation technology in oil and gas multiphase pipeline.Therefore,to apply natural gas hydrate blockage risk control by taking hydrate slurry transportation technology,the regular pattern of hydrate slurry solid-liquid flow characteristic should be mastered.Hydrate slurry solid-liquid flow mechanism model in the horizontal tube has been established in this paper,which is applied to water-in-oil system.The model is in reference to the basis of the classic three layers of solid-liquid flow model,combine with the characteristics of hydrate slurry,solid particle dynamics and the theory of multiphase flow,and it is solved numerically in Gauss-Newton method.Compared with high-pressure hydrate slurry multiphase flow experimental data,the feasibility of the solid-liquid flow mechanism model is verified.Then,the factors that influence on the model critical parameters: deposition velocity,mobile layer height and system pressure drop are analyzed in detail.At the last,the model is applied to calculate the lager diameter pipeline operation conditions.Obtained the pressure date of different hydrate particle concentration,oil viscosity,hydrate aggregate size,and the calculated pressure variation trend is accord with the high-pressure hydrate slurry multiphase flow experimental trend,this shows that the model can be applied to the larger diameter pipeline. |
