| It has proven that there are a lot of natural gas hydrate resources in the continental shelf of the South China Sea and continental permafrost zone. Gas hydrates have high energy efficiency. Their combustion products do not pollute environmental, so they can be used as an important alternative energy sources of the future. The gas hydrates has become a new energy for which Countries are competing in-depth study of one kind of new energy. In particular, the study of the mechanism of the hydrate formation has great significance in China’s energy strategy because of its high energy efficiency. Because in reality, the actual sample by mining to obtain is more difficult, therefore, preparation in artificial laboratory has become an important research method. In this paper, a method of generating gas hydrate commonly used in laboratory is PVT. By observing the changes in temperature and gas pressure, we judge the situation which generates hydrate. The study of the impact factors include the initial temperatures initial pressures initial ice particle sizes the second boost heating and temperature changes.We study the effect on the process of the hydrate generating from pure ice and ice containing a surfactant to provide a high promote methods for generating high saturation of hydrate. The main work is as follows:By studying the factor affecting the process of hydrate formation for the process of generating methane hydrate from pure ice, we find that under the same initial temperature, the high initial pressure plays a very significant role in promoting the formation of hydrate. Under the same initial pressure, when the temperature is far from the melting point, the lower the temperature is,the faster the promoting effect of hydrate generation is. For the latter into the diffusion stage, the second supplementary pressure compared to the secondary heating more help to promote hydrate formation. The temperature is raised to near the decomposition temperature and stabilize for a period of time and then quickly cooled to below the melting point of ice, which generates temperature variations has a certain impact on hydrate generating.It can increase the amount of generated hydrate.In the experiment where ice powder containing a surfactant reacted with methane, generating hydrate,we found that types of ice powder using surfactants and their concentration had a great influence on the initial generation phase hydrate.The types and concentration of the surfactant on the initial formation of the hydrate played a significant role. If surfactants containing different types, at the same initial pressure and temperature, wants to most promote hydrate formation, the concentration of the surfactants required is different.Different types of surfactants, the optimum corresponds surfactant concentration is different. The ice powder containing SDS, comprising surfactant concentration respectively 100ppm、300ppm and 500ppm, in the research of generating hydrate,we found that when the SDS concentration were 300ppm, the surfactant on ice powder had the most significant role in promoting generating hydrate. For the ice powder, when the concentrations of the surfactant containing APG were 100ppm、300ppm、500ppm and 1000ppm. we found that the ice powder containing 1000ppm of APG relatively quickly generated hydrate. At the same time, compared to the effect of surfactants on the initial stages of generating hydrate, the initial pressure was not significant, but the initial temperature of hydrate formation was obvious.. When the reaction reached a steady diffusion phase, the effect of the additional pressure in the experimental was not apparent. The secondary heating also had no obvious effect on the reaction. When the temperature rose to near decomposing point under the pressure, whether the reactor was rapidly cooling or rapid cooling after supplement of gas, they both played a certain role in hydrate generates. Furthermore,we found that the methane gas saturated environment promotes the reaction of the generating hydrate. |
PDF Full Text Request