Method and system for acquiring permeability of sediment containing natural gas hydrate

Abstract

The invention discloses a method and a system for acquiring permeability of sediment containing natural gas hydrate. The method comprises the following steps of adding geometrical characteristic representation array parameters of pore hydrate to a geometric class of a model, adding a pore filling type hydrate model in a pore network model calculation method, building a permeability conduction equation in the state, and calculating the permeability of a pore network model containing the natural gas hydrate. The system comprises a pore network model building module, a pore filling type hydrate model adding module, a permeability conduction equation building module and a permeability calculation module, wherein secondary development can be carried out on the basis of an open-source calculation tool OpenPNM of the pore network model. According to the method and the system, the permeability when the pore network model contains the hydrate and the hydrate does not completely block the pore throat is calculated, the selection of various hydrate positions is provided, and a problem that the permeability of the sediment containing the hydrate changes along with the change of the saturationof the hydrate is solved.

Description

technical field [0001] The invention belongs to the technical field of gas hydrate reservoir formation and development, and relates to a method for calculating the permeability of hydrate deposits, in particular to a method and system for obtaining the permeability of gas hydrate-containing deposits based on a pore network model numerical simulation algorithm . Background technique [0002] Natural gas hydrate is a kind of clathrate compound formed by water molecules connecting small gas molecules by hydrogen bonds [Sloan E D, Koh C A. Clathrate hydrates of natural gas [M]. Third Edition ed. Boca Raton: CRC Press, 2007] , when the gas component is methane-based natural gas, it is also called "combustible ice" because it is flammable. Because of its large reserves, it is a promising energy source, so in the past few decades, major energy-consuming countries have invested heavily in hydrate exploration and development technology research [Li J F, Ye J L, Qin X W, et al al.Th...

AI Technical Summary

Problems solved by technology

However, the actual process of hydrate growth in pores is a gradual process (hydrates gradually block pores), and it is difficult for existing methods to reflect this gradual process in the simulation process, and it is difficult to accurately describe the synthesis and decomposition of hydrates in pores

Therefore, the existing technology applied to the numerical simulation of hydrate saturation and permeability has low accuracy, and it is difficult to solve the problem that the permeability of hydrate-containing sediments changes with the change of hydrate saturation.

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