Friction Pressure Performance of Commonly Used Viscous Gravel-Packing Fluids

Abstract

Gravel packing is increasingly used in long horizontal wells and challenging environments. Key to executing the gravel-pack job successfully is selecting an appropriate gravel-carrier fluid. Frictional pressure loss exhibited by gravel-packing fluids is an important consideration in their selection. This paper discusses the friction pressure performance of commonly used gravel-packing fluids in the industry today, which include the viscoelastic surfactant (VES) types of fluids, xanthan, and hydroxyethyl cellulose (HEC).In wells with a long horizontal section or narrow margin between pore pressure and fracture gradients, the frictional pressure loss exhibited by these fluids in the wash pipe and washpipe/base-pipe annulus governs whether these wells can be gravel packed without fracturing the formation. In gravel packs with alternative-path configuration (shunts), the frictional pressure loss through the shunts controls the maximum length that can be gravel packed.This paper discusses in detail the fluid friction pressure performance while pumping these fluids through various conduits including circular pipe, eccentric annuli, and rectangular tubes (shunts). These data were generated in field-scale yard tests under controlled conditions, for both ambient and elevated temperatures. The paper also discusses the rheological properties of these fluids at ambient and elevated temperatures. The effect of factors such as surfactant/ polymer concentration, addition of gravel, and temperature on the frictional pressure loss of these fluids is presented, which will help in fluid selection/optimization under different scenarios.

Turbulent drag reduction of viscoelastic wormlike micellar gels

“…The focus of our experiments is a viscoelastic surfactant (VES) similar to an EDAB solution, which was subject of a recent rheological study by Gupta et al [21]. In addition to the aforementioned rheological studies, turbulent flow investigations have been rare, with the only published data being from Jain et al [16] and Goyal et al [17]. However, they only presented friction factor data as a function of the Reynolds number with limited rheological measurements.…”

“…The particles are then placed between the reservoir and a mesh screen to act as a filter to sand particles and to add structural rigidity the well [15]. Examples of gravel-packing fluids are xanthan gum and zwitterionic surfactants in semi-dilute concentrations [16,17]. In this paper, we put forward an experimental investigation of the turbulent flow of one such surfactant solution, which was recently characterized via shear rheology for the most part [18,19,20,21], but whose high Reynolds number turbulent characteristics are relatively unknown.…”