Worldwide's First Time Successful Hydraulic Fracture Operation Through GRE Composite Fiberglass Lined API 5CT Carbon Steel String

Abstract

In an attempt that is considered the first in well stimulation techniques by means of Hydraulic Fracture practice in GRE lined tubing, Badr Petroleum Company, BAPETCO (A SHELL Joint Venture in Egypt) has a successful experience to report. The company performed a hydraulic fracture operation through one of its water injection well installations completed with GRE (fiberglass) lining. The need for fiberglass tubular lining raised from the fact that the injected water in Neag-1 field is saturated with 1000 ppb of oxygen content and a range between 60,000 to 80,000 of salinity which led to an active corrosion cell within the downhole injection strings. The company has been using GRE fiberglass lining for their downhole tubing since 2013 for corrosion protection. However, whenever a frac job was required in a GRE lined string, the tubing had to be pulled out of hole, a frac string had to be run allowing for flowback through the temporary frac string and then the GRE lined string to be re-run again. This sequence of processes lead to a significant downtime and increased workover costs. The concerns about the hydraulic fracture jobs with a GRE lined string came from the fear that the proppants flowing back would erode away the internal GRE lining. There was no availability of any test reports on erosion from conditions mimicking frac jobs through GRE lined tubing that could duplicate the flow back conditions. In two of the wells already completed with GRE lined tubing since 2014, the operations required hydraulic fracture job to be carried out using proppants. The injection rates were high at 20 barrels per minute (28,800 bpd flow rate) for a period of 30 minutes. The proppant injection pressure was 4000 psi. The flow back (cleaning post frac) took 24 hours to complete. 90,000 lb of proppants was injected. At the completion of the fracture job operations in 2018, no returns of GRE or flare or corrosion barrier ring pieces were collected in the surface. The paper will share the intervention jobs that have been recently run through the tubing that corroborates with the fact that the GRE lining inside the tubing is intact. This paper demonstrates the preparatory steps taken by the company to carry out hydraulic fracture jobs through a fiberglass GRE lined string and the learnings from this operation. It also sets a new limit on the erosional resistance of GRE lined tubing. The paper will also highlight the gains of Bapetco utilizing GRE within their water injection wells for corrosion protection. The injection flowrate gains will also be shared in detail, as well as the economic gains of performing the frac job through an already RIH GRE lined string instead of using the conventional frac string operation procedures.