A Novel Fluid-Loss Control Pill That Works Without Filter-Cake Formation: Applications in High-Rate Gas Subsea Frac-Pack Completions in Indonesia

Abstract

AbstractLoss of completion fluid during a completion or work over operation not only increases the chance of losing control of the well, but also can severely damage the formation. The best industry recognized method to stop fluid losses into the formation is to use mechanical fluid loss control devices. However, sometimes, the use of mechanical fluid loss control device is not applicable. Two examples where fluid loss control devices are not applicable are (1) Shoot and Pull Tubing Conveyed Perforating (TCP) before a gravel pack or a frac pack, and (2) Single trip perforating and gravel pack or frac pack completions. In these cases the use of fluid loss control pills is necessary. Traditional fluid loss control pills are associated with formation damage, clean up trips and annular pack plugging. This paper presents the application of a Viscoelastic Surfactantbased non-damaging lost circulation pill (VES-PILL) during the completion of sub-sea gas wells in the South China Sea for ConocoPhillips.This novel solids-free fluidloss control pill was applied to insure well control after perforating and before frac packing. This paper describes the cases from the two wells of which one was completed as a single trip multi-zone frac and pack completion and the other as commingled stack frac packs. These commingled stack frac packs consisted of multi-zone frac packs and gravel pack on bottom and a conventional frac pack on top. Both single trip completions considerably exceeded the world record for the longest single trip gravel packed completion. In the first well, well control was achieved and the losses were controlled from 322 bph to 8 bph. In the second application, during a traditional shoot and pull, the losses were controlled from 60 bph to 0 bph. After completion, the wells were tested at 87 and 55 MMSCFD at 400 psi WHP, and were found to exceed pre-drilling production estimates by about 17-24%. This further confirms the non-damaging property of this VES-PILL.