An Analysis for the Influences of Fracture Network System on Multi-Stage Fractured Horizontal Well Productivity in Shale Gas Reservoirs

Abstract

This paper presents two representative models to analyze the flow dynamic of multi-scale porous medium in hydraulic fractured horizontal shale gas wells. In this work, considering the characteristic mechanisms (multi-scale porous space, desorption and diffusion), flow equations in shale are established. After that, two representative models (discrete fracture model and dual-porosity model) are tailored to our issues. Solved by the control-volume finite element method (CVFEM), influences of fracture network system on productivity in shale reservoirs are analyzed in detail. Based on the analysis, the effects can be summarized as follow: at the beginning of production, high conductivity fracture network means more free gas could be produced; at the later part of production, high conductive fracture network can form a large low pressure region, which can not only stimulate the desorption of adsorbed gas, but also reduce the flow resistance to the well. Finally, the sensitivities of characteristic parameters in shale are discussed.

Multifracture response to supercritical CO 2 ‐EGS and water‐EGS based on thermo‐hydro‐mechanical coupling method

“…Distribution of stimulated and natural formation fractures (modified from Zhang et al) [Colour figure can be viewed at wileyonlinelibrary.com]…”

A Multi-Parameter Optimization Model for the Evaluation of Shale Gas Recovery Enhancement

“…The commercial development of shale gas has been driven by three key advances in technology and science: (1) horizontal well plus multi-stage hydraulic fracturing [1][2][3][4][5][6], (2) the understanding of gas storage mechanisms [1], and (3) the understanding of multi-scale mechanisms of gas flows from shale matrix to hydraulic fracture [7][8][9][10]. A shale gas reservoir has free gas stored in matrix pores and natural fractures, and adsorbed gas on the organic matter [11,12].…”

Sealing Failure Analysis on V-Shaped Sealing Rings of an Inserted Sealing Tool Used for Multistage Fracturing Processes

“…Multistage fracturing technology is a method widely used in oil/gas reservoir stimulation. In the process of performing the multistage fracturing [3,4], an inserted sealing tool is frequently used in downhole operations to connect the upper tubing and lower fracturing string so as to balance the downhole pressure and prevent the fracturing fluid from flowing backward or overflowing. A typical inserted sealing tool used in the field is shown in Figure 1.…”