This was as a result of treating the well with an ORCA for OBM breaker fluid, one of Cleansorb’s range of well treatment fluids. This formulated fluid removes drilling damage caused by oil-based drill-in fluids in open hole sections of production and injection wells. Water injection across the open hole section of the targeted well, newly drilled offshore, was expected to be impaired by residual drilling damage unless a remedial drilling damage removal treatment was applied. This was a particular concern, as 'backflowing' the injection well in the production direction to remove drilling damage before starting water injection was not possible.
In order to treat the 5000 ft openhole section liquid, OBM was displaced to 1.09 s.g. NaCl brine without fluid losses to the formation. To remove OBM drilling damage, ORCA for OBM breaker fluid was then displaced from the toe to the heel of the open hole section and left in place for approximately one week to solubilise hydrocarbon and water wet and dissolve carbonate mud solids. Meanwhile the upper completion was being run.
Following treatment, the water injection rate was 10% above the target rate without exceeding maximum injection pressure. This was despite the challenge of having to remove OBM-based drilling damage to attain the required water injection rate offshore without backflowing the well. The operator considered the well treatment a definitive success, as it was conclusive proof that ORCA for OBM can be used to remediate the most challenging scenario they face: OBM drilling damage in water injection wells.
“Eliminating oil-based mud filter cake damage can be challenging. In this case, it was complicated by the fact that the well was located offshore, where operator concerns about the effect of hazardous chemicals on the environment are at an all-time high,” said Ian McKay, Director & Co-founder of Cleansorb. “The good news is that we developed ORCA for OBM with these specific concerns in mind. Compared with conventional acids commonly used to clean up filter cake following drilling, ORCA’s benign chemistry means that it is extremely low hazard for both the environment and those who use it. Not only does it leave the well free of OBM damage, it’s simple to use and achieves results quickly, without affecting the environment.”
Read the article online at: https://www.oilfieldtechnology.com/product-news/17062019/well-treatment-solution-increases-production-and-water-injectivity-offshore-middle-east/