Coiled Tubing-Assisted Real-Time Temperature Mapping for DiscerningCompletion Integrity Followed by Optimized Placement and Evaluation of aPorosity Fill Treatment for Water Shutoff in Dual-String Completion Wells:Customized Solution

摘要

Increasing water cut and well integrity are currently major concerns,particularly in mature fields.Excessivewater production can detrimentally affect the profitability of hydrocarbon-producing wells if not controlledproperly.This paper describes a successful zonal isolation case study in a dual-string completion wellwith well integrity challenges and variable permeability intervals using a modified organically crosslinkedpolymer(m-OCP)and coiled tubing(CT)-assisted real-time temperature sensing for effective placementand post-operation evaluation.The m-OCP system is a combination of a thermally activated,organically crosslinked polymer andparticulate material for leakoff control to help ensure shallow matrix penetration.It is acid resistant,H2Stolerant,has controlled penetration,and is easy to clean up using a rotating wash nozzle.The settingtime can be accurately predicted with simple laboratory tests.These characteristics make this system thepreferred choice compared to the traditional cement squeeze method that is both time consuming andexorbitant.Diagnostic services delivered by CT-conveyed fiber-optic distributed temperature sensing(DTS)that add real-time capabilities to monitor well integrity assess reservoir performance and visualize treatmentefficiency.Using real-time diagnostic services,tubing integrity was confirmed,and the treatment was placedin the same run,helping eliminate the possibility of an undesired leakoff.After allowing the setting time,a successful pressure test or post-cleanout DTS(in case pressure test is not feasible)was used to establishthe reliability of this method.The first attempt was made on Well A of the field;however,isolation was successful using m-OCP andconventional CT.Operation execution and production recovery took more time than planned because ofthe uncertainty concerning well integrity in the dual-string completion and lost circulation in the depletedreservoir,which affected the economic deliverability of the operation.The major challenges with Well Bof the same type in the same field remain the same.Thus,as part of lessons learned from the previousintervention,diagnostic services were chosen for a real-time evaluation of the completion to review well integrity and accurately place the optimized treatment,thereby helping improve overall results in the mosttime-saving and lucrative manner.The successful isolation of the water-producing zone/perforations in the southeast Kuwait field using m-OCP and CT-assisted real-time DTS to review well integrity can be considered a best practice for addressingsimilar challenges globally.