Simulating device and method for water producing source and pressure-dropping path during coal-rock reservoir discharge and recovery

Abstract

The invention discloses a simulating device and method for a water producing source and a pressure-dropping path during coal-rock reservoir discharge and recovery. The simulating device comprises a sample clamping assembly, a stratum pressure simulating assembly, a fluid supplying / discharging assembly and an information acquisition and control assembly. The sample clamping assembly comprises at least one clamping device, and each clamping device comprises a coal sample clamping device body and a rock sample clamping device body arranged above the coal sample clamping device body. The stratum pressure simulating assembly comprises an oil tank, an oil pressure pump, a flow divider, an axial pressure loading cylinder and a confining pressure loading cylinder. The fluid supplying / discharging assembly comprises a fluid storage tank, a booster pump, a quantitative fluid storage tank and a simulating shaft. Through the simulating device and method, the developing characteristic, the permeability and the water-bearing property of different fractures and flowing of fluids in and between rock stratums in the coal-rock reservoir discharge and recovery process in a combination mode can be simulated, and scientific bases are provided for judgment of the water producing source and the pressure transmission path under the corresponding geological condition.

Description

technical field [0001] The invention belongs to the technical field of coal-rock testing devices, and in particular relates to a coal-rock reservoir drainage production water source and pressure drop path simulation device and method. Background technique [0002] When developing coalbed methane on the ground, the gas adsorbed in the coal reservoir is desorbed mainly through the method of "drainage-depressurization". Therefore, only when the reservoir pressure drops below the critical desorption pressure, can the coalbed methane desorb-migrate-produce out. The drainage of coalbed methane wells is carried out in three-dimensional space. The lithology, permeability, water content, thickness, etc. of coal seams and surrounding rocks cause differences in water production sources, liquid supply capabilities, and effective pressure propagation distances in coal seams during drainage and production of coalbed methane wells. The difference will ultimately affect the gas production ...

AI Technical Summary

Problems solved by technology

[0004] During the drainage process of coalbed methane wells, it is impossible to control the production of coalbed methane wells under coal reservoirs and surrounding rock combinations with different permeability, water content and reservoir pressure. The source of water is unknown and the distance of pressure propagation is unclear, which seriously affects the problem of accurate prediction of gas production. The invention provides a device for identifying the source of water production in the process of coal reservoir drainage under the conditions of different coal seam and surrounding rock combinations.

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