Technology Research On Strengthening NGH Formation By Spiral Pipe Flow And Surfactant

Natural Gas Hydrate is honoured as the most commercially-viablestrategic resources in21st century, and it is also considered to be a highlyefficient gas reservoir for its special cage crystal structure with great gasstorage capacity, which provides a new way to gas storage and transportationtechnology. The primary reasons restricte NGH development are lowformation and growth rate and discontinuous producing. The surfactants aspromoting agent of gas hydrate were verified providing a effective method forindustrial application of NGH transportation and storage technology. In orderto reveal the mechanism of surfactant accelerator on gas hydrate and explorethe effect on CO2hydrate formation,the paper adopt spiral pipe flow andsurfactant compound method to promote gas hydrate formation on the base ofcollection of existing research results home and abroad.New ionic liquidshydrate promoting agent were synthesized and the thermodynamics andkinetics of promoting effect were studied systematacially.First of all, this paper sketched the basic concept of gas hydrate andintroduced the advanced application technology of gas hydrate, comparedstrengths and weaknesses of traditional storage and NGH transportationtechnology. Aim at our research orentation, dynamics mechanismvarious oftypes of surfactant on gas hydrate were expounded. In addition, nature ofthe ionic liquid surfactant were summarized.Secondly, it is biosurfactant rhamnolipid R4and autonomous synthesisedionic liquids hydrate promoting agents [MIMPS] DBSA;[PYPS] DBSA;[PIPS] DBSA was used in CO2hydrate promoting formation experiment.Surface tension of the rhamnolipid R4and other ionic liquid solution weremeasured at different temperatures. The changeing law of between thesolution surface tension and temperature and concentration was researchedand Surface enthalpy entropy Ss and surface enthalpy Hs of hydrate formationsolution were calculated in different promoting agent. The correlationsbetween gas hydrate formation rate with the surface tension of solution wasestablished. Thirdly, the thermodynamics and kinetics of CO2hydrate generationexperiment using the promoting agent above were researched. The paperstudied the effect of rhamnolipid and other three kinds of ionic liquids on CO2hydrate phase equilibrium condition at different temperatures. The phaseequilibrium pressure of CO2hydrate in every kind of promoting agents wasdetermined to analyse and contrast so that the best range of thermodynamicpromoting concentration of every promoting agents can be confirmed. It alsostudied effect of three kinds of ionic liquid on kinetic parameters of CO2hydrate and researched CO2hydrate formation time, generating rate and gasconsumption in various kinds of promoter system. In addition CO2gasconsumption was calculated by reduced equation of state. The experimentalstudy on the pipe flows reinforce natural gas hydrate formation wasinvestigated. The characteristics of hydrate formation in pipeline were studied,and the induction time and the generation time of hydrate formation withdifferent velocity and different twist rate were studied.