Advanced Flowback in the Powder River Basin: Securing Stimulation Investments

Campos, Mario (Schlumberger) | Potapenko, Dmitriy (Schlumberger) | Moncada, Katharine (Schlumberger) | Krishnamurthy, Jayanth (Schlumberger)

OnePetro 

Abstract

An optimized stimulation and flowback strategy was devised from formation structure and reservoir properties in the Powder River Basin (PRB) to keep fluid production rates and bottomhole flowing pressure (Pwf) inside a secure operating envelope (SOE) of operational parameters. Keeping operations within the SOE helps ensure

  • Long-term preservation of propped fracture connectivity to the wellbore by minimizing proppant flowback and the associated pinch-off risk.
  • Reduction and/or elimination of a remedial lateral cleanout.
  • Reduction of sand-related well and surface facilities failures such as worn standing valves, junked pumps, and abrasion-related surface leaks.
  • Reduction of proppant waste and its disposal associated costs by keeping proppant inside the fracture network and not flowing it back.

Well completion design and proppant placement are understood across the industry, but more recently long-term stimulation integrity has become more of a focus. A look-back analysis of offset wells showed considerable amounts of proppant produced during flowback. Traditional flowback approaches focus on surface rate control rather than differential pressure across the proppant pack. The pressure and flow rate are both drivers for proppant production risk.

A geomechanical earth model and stimulation design were used to establish an advanced flowback strategy to minimize risk of proppant flowback. Communication protocols between operations and engineering teams, a tailored SOE, and a flow simulator were then used to make on-time choke size decisions that maximized early-time production and minimized proppant flowback.

Using this advanced flowback strategy, an average of 30 pounds of proppant per well was estimated to be produced using hourly samples during the early production of the well compared with an average of 75,000 pounds of proppant per well recovered before the implementation of this strategy. The engineered flowback approach was implemented in a total of 15 wells with repetitive success that materially helped position these wells as top quartile producers within the PRB.

Based on the results of the implementation of this methodology, the engineered flowback approach was adopted as a standard operating practice within the production management organization of a major oilfield service provider in all assets in which wells are completed using hydraulic fracturing stimulation.