Pedchenko N. Improvement of methods of gas hydrate deposits development and control of hydrate formation

The dissertation presents a theoretical generalization and solution to the scientific and practical task of increasing the efficiency of the gas extraction and transportation technology of marine deposits. The purpose of the work is increase the efficiency of the development of gas hydrates marine deposits by improving technology based on energy-efficient technological solutions and managing man-made hydrate formation. Based on the research results, the mechanism of influence of submerged jets on natural gas hydrate in the composition of hydrate-bearing rock is proposed. The mechanism of gas hydrate extraction from marine deposits without spending thermal energy on its melting is substantiated. It involves stimulation of gas hydrate recrystallization as a result of the combined effect of submerged water jets and associated processes. A gas hydrate extraction method has been developed and substantiated. At the same time, the principle of energy-efficient liquefaction for hydrate-bearing rock and the initial gas hydrate separation is proposed and substantiated, which, provided that the minimum distance between the hydromonitor and the fracture front is maintained, provides: disintegration of the rock with a high-pressure jet; partial dissociation of the gas hydrate due to the heat dissipation of jet energy and rock inclusions release as a result; repeated hydrate formation after gas escapes from the overheated zone, but without agglomeration with the rock. The principle of the process for underground gas hydrate separation from the hydro-mixture is also proposed and substantiated, which involves the formation of a mine in the hydro-mining process, the gravitational separation of the hydro-mix in it into rock sediment and gas hydrate concentrate, and its selection from the concentration zone. Also, the mechanism of anomalous the gas hydrate stability when it comes into contact with a high-concentration inhibitor solution is recorded and theoretically substantiated, which consists in the formation of a ice layer on the hydrate crystals surface, which prevents its direct contact with the inhibitor. The established mechanism of phase transformations in the presence of a concentrated solution for an thermodynamic action inhibitor should be taken into account in case of complications in the systems of collection and preparation of oil and gas industry products.