An experimental device and experimental method for simulating shale gas fracturing process

Abstract

An experimental device and experimental method for simulating the shale gas pressure fracturing process belong to the technical field of shale gas mining engineering. The invention is composed of a true triaxial loading unit and a pneumatic fracturing system unit. The true triaxial loading unit provides true triaxial stress loading. Under the true triaxial stress state, the pneumatic fracturing system unit simulates the shale gas pressure fracturing process to meet the gas pressure requirements. The fracturing simulation indoor experimental requirements meet the requirements of gas pressurization, realize fracturing and crack expansion of shale samples, and realize waste gas recovery; it can measure the stress-strain relationship of shale samples before the air pressure fracturing experiment, and the shale test After the sample is fractured by air pressure, the change in permeability of the shale sample before and after fracturing can be directly measured and compared to accurately evaluate the fracturing effect; by replacing the fracturing gas in the high-pressure cylinder, it can help the experimenter find the most suitable Fracturing gas, and helping experimenters study the cracking mechanism of shale, providing a theoretical basis for fracturing to increase production.

Description

technical field [0001] The invention belongs to the technical field of shale gas exploitation engineering, and in particular relates to an experimental device and an experimental method for simulating a shale gas pressure fracturing process. Background technique [0002] As a kind of unconventional natural gas, shale gas’s exploitation technology is different from that of conventional natural gas, and mainly includes hydraulic fracturing technology and gas pressure fracturing technology, among which hydraulic fracturing technology is the most mature in the United States, but hydraulic fracturing technology The technology consumes a lot of water resources, and a large amount of chemical agents need to be added to the water, which leads to the pollution of groundwater. Therefore, from the perspective of environmental protection, hydraulic fracturing technology is not environmentally friendly. [0003] Gas fracturing technology, as the latest mining technology, has the advantag...

AI Technical Summary

Problems solved by technology

[0004] At present, in order to further study gas fracturing technology, it is essential to carry out fracturing simulation laboratory experiments, but the existing fracturing simulation laboratory experiments are all aimed at hydraulic fracturing technology, and are used for shale hydraulic fracturing. The experimental device cannot be simply transplanted or adjusted to a shale gas pressure fracturing experimental device, and some existing gas fracturing experimental devices can only meet the fracturing simulation indoor experiments under conventional triaxial conditions. At this stage, there is no shale gas pressure fracturing experiment device. The fracturing experimental device can meet the fracturing simulation indoor experiments under true triaxial conditions, but it cannot achieve the purpose of finding suitable fracturing gas, nor can it accurately evaluate the fracturing effect

Images