Mechanism of Frequency Conversion Vibration Stimulating Exploiting Technology with Marine Gas Hydrate and its Numerical Simulation

Abstract

Gas hydrate is a new energy in the 21st century with the characteristics of high energy density, huge amount of resources and cleaning. It has important significances for resources development, environmental protection and global climate changing. Due to the limitations of the occurrence mode and the technical level of marine gas hydrates, at present, the development and utilization of the resources are still tentative. This article analyzed and evaluated several key technologies to develop marine gas hydrates, that is depressurization, thermal methods, chemical injection method, CO2 replacement method, and fluorine gas+microwave method. However, these methods are difficult to control in the mining process. The research based on the properties of the occurrence of marine gas hydrate, used the principle of gas hydrate decomposition caused by vibration, by adjusting the excitation intensity, frequency, and amplitude. Different local oscillator strength applied on the Occurrence of gas hydrate layer. Gas hydrate stable state changed in mining region, prompting the gas hydrate conversing from solid to gas. Numerical simulations show: Low-frequency vibration should be used in the layers with higher hydrate saturation. The vibration frequency should be improved in the layers with lower hydrate saturation. The method has a good controllability for the region and the process of mining, avoiding geological disasters and environmental issues in the seabed caused by the mining process losing control.