Experimental Research On Physical Parameters Of Natural Gas Hydrate Sediments

As a potential sustainable development of mineral resources in the future,natural gas hydrates are stored in the natural world due to clean and non-polluting after combustion,and the researchers believe that they are the most valuable energy sources for mining and utilization.Natural gas hydrates are mostly found in seabed sediments.The seabed area is characterized by difficulty in core removal,complicated process and high core cost.This paper synthesizes natural gas hydrate by SHW-3 hydrate rock sample acoustic power test device.Sediments and experimental studies.In this paper,a series of experiments on the synthesis of natural gas hydrate deposits were carried out by using the SHW-3 hydrate rock sample acoustic power test device.The research contents include:experimental study on the influence of the particle size of a single type of sand particles,the experimental study on the influence of the proportion of mixed sand components,and the experimental study on the influence of the particle size of mixed sand particles.Firstly,combined with the mechanism and characteristics of hydrate synthesis,a method for calculating the pore saturation of natural gas hydrate deposits in loose porous media is presented.Then,the particle size of sediment particles and the mixing of different sediment particles are studied by acoustic-electric technology.The influence of physical,electrical,mechanical and other physical parameters in the synthesis of natural gas hydrate sediments,and finally the analysis and summary of the changes of physical parameters,combined with the theory of natural gas hydrate synthesis and rock mechanics related theory to give the mechanism and reasons for the change of physical parameters.Research indicates:(1)In the 22 groups of experiments,For natural gas hydrate deposits synthesized by single sand,the shear wave velocity,longitudinal wave beam and resistance resistance value after the end of synthesis increase with the decrease of sand particle size.With the increase of the number of synthetic sands in natural gas hydrate deposits,the ability to resist compression deformation is gradually enhanced,the degree of cementation is gradually increased,and the Young's modulus and bulk modulus are also increasing.When the same number of meshes,the brown corundum sample is stronger than quartz sand,and the dynamic Poisson ratio has no obvious regularity after comparative analysis.(2)After synthesizing natural gas hydrate sediment samples by mixing mesh sand,the sonic wave velocity,bulk modulus,Young's modulus and resistance resistance are closer to the synthetic samples of single sand with higher mesh number.The ability of natural gas hydrate deposits to resist compression deformation gradually increases with the increase of high mesh sand content in synthetic sand.(3)Mixing the same mesh of brown corundum with quartz sand for the synthesis of natural gas hydrate deposits.By comparing the experimental data,it can be concluded that the longitudinal wave velocity of the pure sand mixed sand sample is significantly closer to that of the quartz sand sample.The longitudinal wave velocity of the sample is between the quartz sand and the brown corundum single sand sample.The Young's modulus and bulk modulus of the natural gas hydrate deposits after synthesis are closer to those of quartz sand.(4)When single sand is synthesized into natural gas hydrate deposits,when the mesh number of synthetic sand is more than 200 mesh,the synthesis time of hydrate in the sediment is greatly shortened,and the synthesis time can be shortened to 30?46 min.When the natural gas hydrate deposits are mixed with different meshes and the higher meshes reach a certain proportion,the hydrate synthesis is more effective than the single mesh,and the synthesis time can be shortened to 18?25min.