Development of Hydraulic Fracturing Evaluation Techniques Using Microchip Sensing System
Authors: Zhang Shang , Zheng Danzhu , Yu Mengjiao , Jakaria Md 
Published: August 2024

A successful hydraulic fracturing operation is the key to enabling economic production from low permeability reservoirs. In order to identify problems during the fracturing job and optimize the hydraulic fracturing design for future development, an effective method for monitoring and evaluating the hydraulic fracturing operation is needed. Due to the complex nature of the process, most of the existing techniques for hydraulic fracturing diagnostics and evaluation are limited.

In this research, a comprehensive hydraulic fracturing model was first developed to study both pressure and temperature responses during the operation for injection and warm-back, considering the dynamic fracture propagation, dynamic fracturing width growth, and dynamic pressure-dependent fluid leak-off. The model was validated with well-known analytical models.

A cost-effective distributed microchip sensing (DMS) system was developed and tested under in-situ conditions. Laboratory test results showed that the DMS system provided reliable pressure and temperature data at the perforation inside the wellbore. The deployment cost of the distributed microchip sensing system would be only a fraction of current measuring techniques, such as fiber-optic sensing. The DMS system will benefit the hydraulic fracturing design and fracture efficiency evaluation.

1. INTRODUCTION

Hydraulic fracturing is a process that could improve the recovery of hydrocarbons from formations, especially for low permeability formations. A successful hydraulic fracturing operation is the key to enabling economic production from low permeability reservoirs. Because of lacking affordable data acquisition technologies during the operation, it has been a "black-box" tool for the industry for decades, although many researchers have tried to measure or numerically describe the hydraulic fracturing process (Warpinski et al., 1994; Cipolla & Wright, 2000).

One of the reasons for this situation is the difficulty of verification. The actual fracture geometry that is located at extreme in-situ conditions thousands of feet under the surface is nearly impossible to obtain directly. Another reason is that the whole process is extremely complex. A poorly designed operation or problems during the fracturing job, such as inadequate fluid volumes, inappropriate proppant selection, and insufficient treatment stages, would result in a less efficient fracture network, contributing to the flow in the production phase (Sinha & Ramakrishnan, 2011). A poor hydraulic fracturing job will also influence the zonal isolation and cause cement failure (Zheng et al., 2023; Zheng et al., 2024) If no proper evaluation techniques were deployed during the fracturing operation, operators could not realize the underperformance of the well until it had been put into production for a while. Since then, a workover or re-fracturing job has been needed to optimize production, which would cause a considerable amount of extra cost and an enormous amount of non-productive time (NPT).