Research Progress Of Gas Lift Mining And The Imagination Using Gas Lift System To Extract Natural Gas Hydrate

Today in the 21 st century,the rapid development of the global economy is accompanied by a large amount of traditional energy consumption and serious damage to the natural environment.In this situation,people urgently need to find new clean energy.Natural gas hydrate,also known as combustible ice,has the advantages of huge reserves,cleanliness,and high calorific value.It is recognized as the best alternative energy source for traditional energy in the 21 st century.So far,there have been several trial productions of natural gas hydrates in the world,and the field of deep-sea mining has also been developed for many years.In this paper,by enumerating and analyzing the advantages and disadvantages of each mining method,this paper puts forward the idea of combining solid fluidized mining with the most recognized deep-sea mining gas lift system to extract natural gas hydrate.Based on the enumeration and summary of the current research progress of multi-phase flow pattern classification,gas lift theoretical model,gas lift system performance,gas lift system lifting efficiency and other factors,The theoretical model of the gas lift system with wider application and less error is summarized,include: solid-phase lift critical velocity models and gas lift system lift efficiency models.Examples are the on-site gas lift experiment in the coastal sand mine,the indoor gas lift experiment in the borehole hydraulic mining,the borehole hydraulic mining lift experiment in the iron-manganese lead-zinc mine area,and the indoor series of experimental research on the gas lift system in the Professor Tangchuanlin's project group.(1)The use of gas lift system with drilling hydraulic and pulse jet methods can greatly reduce the development cost and improve the lift efficiency;(2)The gas injection system theoretically indicates the deeper the position of gas injection,the higher the lift efficiency,but The economic cost needs to be considered,so the selection of gas injection depth should be combined with the actual working conditions to select the optimal value;(3)The lift performance of the gas lift system increases first to the maximum value and then slowly decreases with the increase of the gas injection volume.The principle is the conversion of the internal flow pattern of the lift pipe controlled by the gas injection volume;(4)Under the same gas injection volume and gas injection depth,the lift performance of the gas lift system will increase with the increase of the immersion rate.Aiming at the deep-sea weakly cemented natural gas hydrate,an idea of lifting to the sea surface through a deep-sea mining gas lift system after solid fluidization is proposed.The liquid velocity,the coefficient of drag along the solid-liquid mixed fluid,the critical gas injection depth,gas injection pressure and gas injection volume,the hydrate decomposition characteristics in the lift pipe and the mathematical model of the system lifting efficiency.It can provide a theoretical basis for the numerical simulation and experiment of natural gas hydrate exploitation in the later stage.