Unified Fracturing Design for Water Injection Well under Steady State Flow Regime

Abstract

Unified Fracture Design for fracturing optimization is a simple and reliable way to push the limit of the injection ability, reported frequently in recent years. However, most studies focus on fracture design under pseudo-steady state flow regime. The analysis of the different pressure systems between water injection well and oil production well tells us that the steady flow regime in the formation takes up most life span of water injection wells, associated with the field experience. To maximize injection capability for fractured vertical water wells under this regime, a physical optimization method is developed based on the concept of proppant number. Meanwhile, two new type curves without consideration of formation damage are obtained for quantifying the correlation between dimensionless injectivity and dimensionless conductivity. Then, calibrated design procedures accounting for gel damage and non-darcy effect, are also proposed. Finally, sensitivity studies are addressed to clarify the effect of several variables on the optimum fracture geometry.