Implementation of One-Trip Acid-Jetting Solution in AX field for an Operator in Nigeria

Abstract

Abstract The paper describes the integration of Service Provider's one-trip washpipe-conveyed Jetting-tool assembly with an 8.5″ open-hole horizontal stand-alone-screen sand-face completion for optimal delivery of acid treatment to the sand-face of injector well typically performed post completion following poor injectivity. AX field injectivity performance has been on the declined mostly attributed to poor sand development, shorter horizontal interval (Low NtG), fines migration, hammer effect, and ineffective removal of filter cakes. To manage this, Operator employed two main approaches to tackle the problems which include the use of check valve screens and Jetting tool for acid treatment at the sand face to effectively dissolve and remove filter cake following a learning from Gulf of Mexico in 2021 (OTC 31713). The integrated team, comprising of Operator and Service provider carried out extensive design upgrade and modifications of the Jetting tool technology. Additional scope included integration with a separate third-party service tool and adapting a barrier valve's shifter tool in the Jetting tool. The Jetting-tool technology has been successfully implemented in the acid treatment of two injector wells in the AX field with reported early positive signs of improved injectivity thereby removing the high cost of post-completion stimulation to enhance injectivity. This new approach allows the operator to save significant post-completion intervention costs by adding the stimulation capability to the completion phase of the well, obtaining a better well-injectivity performance at a reduced cost which would have been otherwise done with coil tubing.