The influence of the gas hydrates morphology on the rate of dissociation and the manifestation of self-preservation in non-equilibrium conditions

The object for the research was samples of artificially formed gas hydrate of different morphology. Gas hydrates are clathrate compounds of water molecules and hydrate-forming gases. They create significant problems for the oil and gas industry. At the same time, they contain enormous natural gas resources. The study of gas hydrates requires the production of quality samples in laboratory conditions and the availability of appropriate laboratory equipment. However, it is customary to use averaged physical indicators when performing calculations and in works on modeling gas-hydrate processes. At the same time, their morphological differences are not taken into account. Therefore, there is a risk of obtaining distorted research results. Based on this, the paper presents an analysis of the morphological differences of artificially formed gas-hydrate structures depending on the method of their formation. An assessment of the influence of the method of gas hydrate formation and the morphology of artificially formed gas hydrate samples on its stability is also given. In addition, recommendations are provided for choosing a method of forming samples of gas-hydrate structures that simulate natural samples. Gas hydrate samples for research were obtained at a laboratory facility by changing the method of mixing the contents of the reactor. The basis of the research methodology was the analysis of enlarged images of gas hydrate samples. The morphology of the gas hydrate samples was studied through the transparent viewing windows of the reactor. For obtain high-quality images, an optical system with a light source inside the reactor was used. The stability of the gas hydrate samples was investigated with gradual pressure release in the reactor. The difficulty of obtaining adequate samples of artificial gas hydrates for modeling the properties of natural analogues is shown. It is shown that morphological differences in the macro- or microstructure of artificially formed gas hydrate samples can affect the results of research. It was concluded that the results of experimental studies with samples of artificially obtained gas hydrate cannot be considered adequate for real conditions without appropriate corrections.