Study On The Formation Mechanism And Flow Characteristics Of Hydrate In The Pipe Flow System

Hydrate slurry transport technology is becoming a hot topic,and the premise of realizing the true large-scale industrialization is the formation of the hydrate formation mechanism and the flow characteristics of hydrate slurry.In this paper,the present situation and development trend of gas hydrate at home and abroad are analyzed.The conditions of hydrate formation,the prediction model of hydrate formation,the flow property of hydrate slurry and the application of hydrate slurry are summarized in this paper.The characteristics of hydrate formation,formation mechanism,formation conditions,nucleation,macro growth and related aspects of the fluid system were studied.The model of chemical kinetics,driving force,nucleation,induction time,gas consumption rate,hydrate growth kinetics and inhibitor hydrate growth were established.The principle of hydrate formation in the pipe flow system,the phase equilibrium of hydrate in pipeline,the formation and growth characteristics,the prediction of the formation position,the basic characteristics of the hydrate slurry,the macro micro rheology,the flow theory,and the mathematical model of slurry flow are studied.The simulation of slurry flow in the design condition was carried out using CFD/FLUENT Euler-Euler two fluid model.The flow field distribution law in the horizontal circle was simulated by considering the influence of slurry particle size,concentration and flow rate.The flow rate of 4?6m/s was 2?5m/s,and the flow field distribution of 3D was simulated.The results show that the slurry body reaches the full development process at the level of the horizontal circular pipe,and the concentration of slurry in the same concentration reaches the full development process,and the low concentration of slurry reaches the full development of the high concentration slurry.The flow of the slurry in the 90 degree vertical pipe flow,the flow of the elbow is changed,and the pressure,concentration,velocity of the flow field distribution in the elbow,the formation of the two flow,when the slurry is greater than the flow velocity of 6m/s flow,the solid particle concentration distribution in each section,the fluid presents a homogeneous flow state.Finally,the research directions and suggestions for future hydrate slurry flow in the future are proposed.