Methods for stimulation of hydrocarbon-bearing formations while inhibiting corrosion of metal surfaces contacted by acid solutions used in stimulation

Patent metadata

Field	Value
Publication number	US-11840913-B2
Application number	US-202017614181-A
Country	US
Kind code	B2
Filing date	May 8, 2020
Priority date	May 9, 2019
Publication date	Dec 12, 2023
Grant date	Dec 12, 2023

Abstract

A method for stimulation of a hydrocarbon-bearing formation includes inserting a perforating tool and an acidic composition into a wellbore. An outside surface of the tool is pre-treated prior to downhole insertion with a grease containing a first corrosion inhibitor adapted minimize corrosion by exposure of the tool the acidic composition for a duration of the stimulation process. The acidic composition further comprises a second corrosion inhibitor that reacts with the first corrosion inhibitor to generate a corrosion protective layer onto the outside surface of the tool. The method further includes perforating the wellbore with the tool, allowing the acidic composition to come into contact with the perforated area of the wellbore, removing the tool from the wellbore; and initiating the stimulation of the perforated area using a stimulation fluid.

First claim

The invention claimed is:

1. A method for fracking or stimulation of a hydrocarbon-bearing formation, said method comprising:
providing a wellbore to be stimulated;
inserting a plug in the wellbore at a predetermined location;
inserting a perforating tool having an outside surface and a spearhead acidic composition into the wellbore;
wherein said outside surface of said perforating tool is pre-treated prior to downhole insertion with a grease containing a first corrosion inhibitor component adapted to reduce corrosion inflicted upon it by an exposure to the spearhead acidic composition for a duration of the fracking or stimulation and wherein said spearhead acidic composition comprises a second corrosion inhibitor component which reacts with said first corrosion inhibitor component to generate an active corrosion inhibitor, which forms a protective layer onto said outside surface of said perforating tool;
positioning the perforating tool proximate said predetermined location;
perforating the wellbore with the perforating tool thereby creating a perforated area;
allowing the spearhead acidic composition to come into contact with the perforated area for a predetermined period of time sufficient to prepare the formation for fracking or stimulation;
removing the perforating tool from the wellbore; and
initiating the fracking or stimulation of the perforated area using a fracking fluid.

Assignees

• Fluid Energy Group Ltd
• Dorf Ketal Chemicals Fze

Inventors

• Purdy Clay
• Weissenberger Markus
• Lee Adrienne

Classifications

• E21B43/261 Primary

  Separate steps of (1) cementing, plugging or consolidating and (2) fracturing or attacking the formation · CPC title

• C09K8/54

  Compositions for in situ inhibition of corrosion in boreholes or wells · CPC title

• C09K8/74

  combined with additives added for specific purposes · CPC title

• E21B37/06

  using chemical means for preventing or limiting {, e.g. eliminating,} the deposition of paraffins or like substances · CPC title

• E21B43/27 Primary

  by use of eroding chemicals, e.g. acids · CPC title