Operational Improvements Using a Light Work-Over Rig and Concentric Coiled Tubing Vacuum Technology Delivered an Optimized and Cost-Effective Cleanout and Stimulation

Abstract The opportunity to optimize the logistics of cleaning and stimulating beam pump producing wells was identified. The objective was to provide operational expertise and technical know-how to cleanout ultra-low pressure reservoir wellbore and stimulate formation with one integrated solution between a light workover rig and concentric Coiled Tubing Vacuum Technology (CCTVT). The paper will highlight an engineering design for aligned operations between a light workover rig, coiled tubing unit and ancillary equipment. Additionally, the paper will review an advanced mud acid treatment along with highlighting the required downhole tools to successfully deliver work scope. The approach involved a detailed overview of the operational requirement to have a concentric coiled tubing unit working with a light workover rig. The approach involved the rig-up and lifting procedure, equipment, optimization, and connections required for the well control stack to have one integrated solution between workover rig and concentric Coiled Tubing Unit. Details will include how a vacuuming tool delivered an engineered cleanout and will include the process of a specialty mud acid stimulation along with a specific tool across wire-wrapped screens, then vacuum unspent acid to the surface. The paper will highlight how this approach was a cost-effective improvement method over prior practices. The integrated solution has a workover rig and concentric coiled tubing unit working to achieve cost competitiveness, improved efficiency, and a successful reinstatement of oil producers within a single mobilization. Oil producers have suffered with poor inflow followed by pump failures, and it was expensive for the operator to have multiple well interventions to clean out a deviated well with 2.8765-in. wire-wrapped screens at ultra-low pressure reservoir wellbore. This approach conceptualized the concurrent operations of a light workover rig and concentric coiled tubing unit to reinstate these wells instead of workover rig-CTU-workover rig sequential operation to reduce production downtime and cost. This integrated and engineered solution has delivered improved utilization of resources, and increased oil production at a field trail in Marmul field, Oman. The intervention operations result in the wells returning to production within a week time instead of months. This paper presents new insights into an innovative cleanout and combined well intervention solution where more can be done with less. It offers a practical framework for optimizing a light workover rig and a concentric coiled tubing unit at one well intervention. The paper will explain how an engineering design for cleanout and stimulation can be utilized to deliver a successful and cost-effective well intervention.