| Gemini surfactant is a new kind of environmental friendly surfactant,due to its superior promoting performance,it has attracted the attention of many researchers in China and abroad in recent years.This essay chooses two different structures of Gemini surfactants,Dioctyl Sodium Sulfosuccinate（AOT）and Sodium Lauryl Diphenyl Ether Disulfonate(C12-MADS),examine their effects through their influence on carbon dioxide and methane hydrate generation process,and built the model through mechanism analysis.This essay mainly studied as following four plates.（1）AOT plate.Respectively discusses the influence about AOT and kinetics of carbon dioxide and methane hydrate formation.From the thermodynamics point of view,the conditions of different AOT concentrations to carbon dioxide and methane hydrate formation almost have no affection.From the angle of kinetics analysis,through the contrast of the distilled water system and AOT system,the addition of AOT significantly shortened the induction period of methane hydrate.And with the increase of AOT concentration,the slowdown in the rapid growth late area of carbon dioxide and methane hydrate was gradually eliminated.AOT existence improved the hydrate growth rate,especially for the process of methane hydrate formation.（2）C12-MADS plate.Respectively discusses the influence about C12-MADS and kinetics of carbon dioxide and methane hydrate formation.From the thermodynamics point of view,the low concentration C12-MADS has no obvious influence on the formation of carbon dioxide and methane hydrate,but high levels of C12-MADS has certain inhibitory effect on carbon dioxide hydrate formation process.From the angle of kinetics analysis,through the contrast of the distilled water system and C12-MADS system,it is found that the existence of C12-MADS could inhibit hydrate nucleation and growth under the experimental conditions of high temperature,but the inhibition of C12-MADS would transform to promotion with the decrease of the experimental temperature.However,if the experiment temperature is too low,the promoting effect will be weakened.In addtions,the inhibition effect could become stronger with the increase of C12-MADS concentration.The addition of AOT increased the growth rate of methane hydrate,eliminated the induction period and weakened the hydration formation process S trajectory in the distilled water system.The promotion of C12-MADS in methane hydrate formation process was enhanced with the system temperature reduction and the increase of concentration.（3）Gemini and SDS plate.Through analysis between the different structure types of Gemini surfactants and SDS on the kinetics influence of hydrate formation,it is found that the double hydrophobic group structure of AOT is beneficial for increasing the growth rate of type I hydrate and keep high gas storage capacity.The promoting performance of Gemini is better than SDS in the milder experimental conditions.Because of the complexity of the connection between benzene rings and hydrophilic groups in C12-MADS struction,the performance of C12-MADS on type I hydrate growth effect is susceptible to the interference of gas solubility and temperature conditions,C12-MADS can even restrain the growth of the soluble type I hydrate in the case of the certain temperature.（4）Model plate.Based on Chen-Guo double step mechanism model of hydrate formation process,it is assumed that methane hydrate nucleation usually occurred in the induction period,methane gas is adsorped at connection holes between hydrates during the rapid increasing area.And relied on Englezos growth dynamics theory and isothermal adsorption first order reaction kinetics theory,it is developed as the theory model of the kinetics of methane hydrate growth in Gemini system.The average relative error of the model is obtained as 7.17%by calculating.It shows that the presented model has good predictability for methane hydrate growth process. |
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