Testing system and method for simulating hole wall damage condition during exploitation of natural gas hydrate

Abstract

The invention provides a testing system and method for simulating a hole wall damage condition during the exploitation of natural gas hydrate. A model test box device includes a pressure chamber, a soil sample storage chamber, and a pressuring plate for sealing and isolating the pressure chamber and the soil sample storage chamber, wherein the pressure chamber and the soil sample storage chamber are arranged up and down; a vertical pressure system is used for applying pressure to the pressure chamber to push the pressuring plate to move downwards; soil samples are stored in the soil sample storage chamber; through holes are formed in a back plate of the soil sample storage chamber in an array mode, and each of the through holes is connected to a pore water pressure gauge; the left side andthe right side of the soil sample storage chamber correspondingly communicate with a water outlet and a water inlet, a waterproof strain piece is attached to a screen positioned at the water outlet in a bonding mode and is used for measuring horizontal and vertical strain of the screen positioned at the water outlet; a seepage system communicates with the water inlet to input water-air mixture into the soil sample storage chamber; a deformation measuring system measures movement and deformation conditions of sand bodies in the soil sample; and a hole pressure measuring system obtains the spatial distribution and evolution characteristics with time of soil sample pore water pressure.

Description

technical field [0001] The invention relates to a test system and method for simulating hole wall damage caused by sand production during natural gas hydrate mining, which is used to simulate soil sample consolidation deformation, well wall stress-deformation-destruction, and sand particles in the real water-gas flow process. Flow state, pore water pressure and other characteristics. Background technique [0002] Gas hydrate is an ice-like crystalline substance distributed in deep-sea sediments and formed by natural gas and water under high-pressure and low-temperature conditions. It has high resource density, wide global distribution, and extremely high resource value. It is regarded as an important alternative energy source in the post-petroleum era, and thus has become a long-term research hotspot in the oil and gas industry. According to the experience of international gas hydrate trial production, the depressurization method is currently recognized as the best natural ...

AI Technical Summary

Problems solved by technology

[0004] The technical problem to be solved by the present invention is to overcome the defects that the existing conventional test equipment can only study the quality of the sand body during sand production and cannot consider the stress state of the borehole wall, and provide a test system that is more in line with the actual engineering needs. It can meet the test needs of accurate measurement of soil sample consolidation deformation, well wall force-deformation-destruction, sand flow state, pore water pressure, etc. in the real water-air flow process

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