Open Access

ARTICLE

Experimental Study on the Influence of Fracturing Fluid Retention on Shale Gas Diffusion Law

Zhiyuan Yao^1,2,3, Jing Sun^1,2,3,*, Dehua Liu^1,2,3

1 Cooperative Innovation Center of Unconventional Oil and Gas (Ministry of Education & Hubei Province), Yangtze University, Wuhan, China
2 Petroleum Engineering College, Yangtze University, Wuhan, China
3 Hubei Shale Gas Development Engineering Technology Research Center, Yangtze University, Wuhan, China

* Corresponding Author: Jing Sun. Email:

(This article belongs to the Special Issue: Simulation of Flow and Transport Problems in Petroleum Engineering)

Energy Engineering 2023, 120(8), 1853-1866. https://doi.org/10.32604/ee.2023.025846

Received 01 August 2022; Accepted 12 December 2022; Issue published 05 June 2023

Abstract

Shale gas reservoirs have poor physical properties and a large number of micro-nano pores have been developed. Shale gas wells have no natural productivity and need fracturing reconstruction measures to put into production. However, the fracturing fluid will enter the reservoir space of shale matrix after fracturing and affect the production of shale gas. At present, there is no consensus on the influence of fracturing fluid retention on gas well production. Based on this, the paper adopts gas molecular transport analyzer to carry out experimental research on the influence of fracturing fluid on shale gas diffusion law after entering matrix pores. The results show that: (1) Compared with the diffusion capacity of single-phase shale gas, the diffusion capacity of shale gas decreases significantly when fracturing fluid is present in the reservoir; (2) In the process of fracturing fluid flowback, when the water saturation in the reservoir decreases from 50% to 0, the gas well productivity increases by about 60%. (3) When fracturing fluid exists in the reservoir, the pore diameter has an exponential relationship with the shale gas diffusion coefficient, and the diffusion coefficient increases exponentially with the increase of pore diameter. The research of this paper provides theoretical basis for guiding the efficient development of shale gas wells.

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Keywords

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