Barmatov, E, Hughes, T, Li, J et al. (3 more authors) (2021) Staged acid corrosion inhibition for matrix acidizing treatments: Concept summary and performance in laboratory experiments. In: Society of Petroleum Engineers - SPE International Oilfield Corrosion Conference and Exhibition 2021, OFCS 2021. SPE International Oilfield Corrosion Conference and Exhibition 2021, 16-17 Jun 2021, Online. SPE ISBN 9781613997840
Abstract
This paper describes a staged acid corrosion inhibition concept for application in matrix acidizing treatments. The approach optimizes the performance of acid corrosion inhibitor (ACI) formulations used to protect coiled tubing (CT) and downhole casing during acid injection and flowback. The concept relies on polymerizable ACI chemistry.
Matrix acidizing formulations are currently designed with a fixed ACI dosage throughout acid injection. The staged approach uses a higher ACI dosage (first stage) to establish a persistent inhibitor film followed by a lower ACI dosage (second stage) to maintain that film. The persistence of the first stage inhibitor film relies on polymerizable ACI chemistry. Staged performance was evaluated by weight loss and electrochemical testing on CT and casing steels in 15% hydrochloric acid at temperatures in the range 60 to 121°C. Rotating cylinder electrodes (RCEs) were used to compare performance under laminar and realistic turbulent flow conditions. An electrochemical flow cell (EFC) was used to quantify performance when the ACI dosage was changed during flow.
The ACI dosage used in the second stage can be at least one order of magnitude lower than that in the first stage. Staged treatments can be designed for enhanced corrosion protection using a lower total quantity of inhibitor relative to conventional treatments. Optimum first and second stage ACI dosages depend on temperature and metal type. For CT in 15% hydrochloric acid, typical stage 1 and stage 2 dosages are 0.2 and 0.01 %, respectively, at temperatures ranging 77 to 99°C; these dosages increase to 1.0 and 0.05–0.1 % at 121°C. RCE testing showed robust performance under realistic dynamic flow conditions, and EFC testing showed good performance when the ACI dosage was changed during flow.
The staged ACI concept achieves enhanced corrosion protection of CT and wellbore casing using a lower total quantity of inhibitor relative to conventional treatments. The next step is to evaluate the performance of staged ACI treatments in field experiments.
Metadata
Item Type: | Proceedings Paper |
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Authors/Creators: |
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Keywords: | materials and corrosion, riser corrosion, pipeline corrosion, subsurface corrosion, corrosion inhibition, oilfield chemistry, well integrity, h2s management, corrosion management, corrosion inhibitor |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Mechanical Engineering (Leeds) > Institute of Functional Surfaces (Leeds) |
Funding Information: | Funder Grant number EPSRC (Engineering and Physical Sciences Research Council) EP/R511717/1 |
Depositing User: | Symplectic Publications |
Date Deposited: | 28 Oct 2021 15:05 |
Last Modified: | 28 Oct 2021 15:05 |
Status: | Published |
Publisher: | SPE |
Identification Number: | 10.2118/205032-MS |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:179492 |