Constrained Hydraulic Fracture Optimization Improves Recovery from Low Permeable Oil Reservoirs

Abstract

The petroleum industry needs cost-effective hydraulic fracturing technique to increase recovery from low permeable reservoirs. That leads to the widespread use of various fracture optimization methods to find optimum values of controllable treatment design parameters. Inappropriate values of these parameters cause uncontrolled fracture, resulting in unnecessarily high treatment cost and finally low productivity. Application of the designed treatment parameters obtained from many commercial tools may not be successful to the full extent, as the realistic design constraints are not well defined. Such wells invariably display poor post-frac productivity. While understanding the deficiency of these tools, this article presents a model integrating optimization tool with design constraints, design variables, fracture geometry, a production module, and a cost module. The effectiveness of hydraulic fracturing is highly dependent on successful viscosity scheduling of the fracturing fluid and is particularly influenced by fluid flow behavior index, consistency index, and shear rate in the fracture. These parameters are also included in the free design variables in this work for the first time. The integrated model demonstrates its merits with optimum treatment parameters while applying to a low permeable oil reservoir.

Keywords:

• hydraulic fracturing
• improved recovery
• optimization
• treatment parameters

Acknowledgment

The author acknowledges the individual grant from the Research Affairs of UAE University, which has been utilized to complete this work.