Novel Enzyme Based Solution for Stuck Pipe Remediation: A Field Application in Harsh Downhole Conditions

Abstract Enzymatic treatment has long been recognized as an effective and environmentally safe method for removing biopolymer-based drilling-mud filter cakes. However, a novel enzyme system has now been successfully deployed to release stuck pipe in newly drilled wells. Enzymes, as biocatalysts composed of amino acid chains, function by accelerating chemical processes without leaving harmful byproducts. Their efficacy depends on their three-dimensional structure, which determines substrate binding, catalysis, and regulation. This paper demonstrates the application of a specially developed enzyme protein system engineered to withstand harsh downhole conditions while effectively addressing stuck pipe incidents. Stuck pipe contingencies, particularly in horizontal and deviated wells, typically necessitate the use of harsh chemicals such as acids, solvents, and other aggressive agents that pose potential risks to reservoirs and downhole tools. In contrast, the enzyme system introduced in this study efficiently breaks down polymer chains in drilling mud systems, dissolving the filter cake and reducing the surface area of contact, thus enabling the release of differentially stuck pipe. A field application of this novel enzyme technology was carried out in the A & B field in North-Eastern part of India, targeting the middle Y sands. The exploratory well was drilled to a depth of 3564m in an 8½″ hole section using Logging While Drilling (LWD) tools. During the Pipe Conveyed Logging (PCL) operation at 3235m, the string became stuck. Conventional remediation attempts, including mud acid treatment, conventional spotting, and string shots, failed to free the pipe. Given the persistent non-productive time (NPT), the joint operations team opted for an enzyme treatment program. An advanced pre-flush solution was pumped, followed by enzyme application at the stuck region. Within 4.5 hours of soaking, after 9 days of NPT (non-productive time), the drill pipe was successfully freed. DCST (Drill Collar Severing Tool) job plan was subsequently cancelled, and expensive logging tools were retrieved intact, allowing drilling to resume as planned. This successful enzyme application represents a pioneering approach by the Operator and marks the first deployment of this technology in the region to resolve differential sticking. The results underscore the potential of enzyme-based solutions as a viable alternative to conventional chemical treatments, offering an efficient, safe, and environmentally friendly method for mitigating stuck pipe incidents in drilling operations.