frac-pack gas completions The significance of non-darcy and multiphase flow effects in high-rate

Hydraulic fracturing combined with gravel packing in high-permeability gas reservoirs (frac-packing, or F&P) is currently considered the most reliable completion technology for offshore Gulf of Mexico (GoM) completions. Such treatments are designed to bypass damage near the wellbore and prevent formation sand production. Despite the relative maturity of this technology, there has been insufficient focus on non-Darcy flow, particularly in the fracture, in F&P wells in the literature. Previously published work, based on single-phase inflow equations, acknowledged that a very high pressure drop exists near the wellbore in F&P completions, but this has been usually attributed to a limited number of effective perforations. In this work, we used reservoir simulation and an inflow equation for pressure drop across the perforation tunnels to quantify the relative pressure drop contributions in the reservoir, fracture, and gravel pack system. We considered both non-Darcy and multiphase flow in our evaluation. We found that non-Darcy flow in the fracture and perforation tunnels results in substantial near-wellbore pressure drops for typical F&P gas wells with gas rates greater than 0.2 to 3 MMscf/D/ft. Increasing fracture conductivity and fracture lengths and using proppants with lower non-Darcy flow coefficients can help in reducing non-Darcy pressure drops and optimizing F&P completions. Copyright 2004, Society of Petroleum Engineers Inc.

The significance of non-darcy and multiphase flow effects in high-rate, frac-pack gas completions Conference Paper