Affiliation:
1. Halliburton, Neuquén, Argentina
Abstract
Abstract
This paper highlights the successful implementation of a solids-free fluid loss system during Coiled Tubing (CT) interventions executed in the Austral Basin. This treatment contains a low-viscosity, solids-free, Relative Permeability Modifier (RPM) for lost circulation control during sand cleanout operations performed in these low-pressure reservoir wells where the Bottom Hole Pressure (BHP) exceeds the reservoir pressure. Avoiding fluid losses reduces the likelihood of getting stuck CT from settling sand or differential sticking.
Significant experience has been acquired in Argentina using this system to avoid fluid loss during interventions, and the correct system formulation has been defined based on field information, lab testing, and experience. This system was applied mainly during CT sand cleanout operations in cased gas wells with sandstone formations and severe fluid losses. Pills of RPM are pumped and forced into the fractured zone without any damage to the formation before carrying out the CT sand cleanout intervention.
RPMs are being formulated and used within the oil industry to help mitigate fluid losses during intervention. The objective is to decrease the relative permeability to water without any (or minimum) modification to the relative permeability to oil. This methodology can be applied in water-wet formations without oil permeability modification, and in the Austral Basin in Argentina, this implementation has demonstrated its benefits during workover interventions. Following RPM treatments, wells were cleaned out without any circulation fluid losses or stuck pipe issues, leading to the successful execution of planned well programs.
The findings of this study can benefit the oil and gas industry by offering a viable and alternative solution for the intervention of depleted gas wells where it is necessary to avoid any fluid losses to the formation during any workover or CT intervention.