Most of the prolific producer zones of KOC have depleted over the years leading to reservoirs with sub-hydrostatic pressures. Unfortunately these reservoirs are still being drilled as they were being done at its prime. Damage to the reservoir while drilling under over-balanced conditions are not receiving the attention it deserves, leading to further reduction in production and a long term damage yet to be assessed. Recently, a study ascertained feasibility of drilling UBD in Fields of Kuwait. The results derived from this study have showed the way for the future of drilling in Kuwait.
Tangible benefits for drilling underbalanced Horizontals in all the major producing reservoirs are manifold. Properly engineered and executed underbalanced drilling operations would definitely maximize wellbore productivity and provide real time reservoir evaluation, while eliminating fluid losses and increasing penetration rates. Reduction in formation damage due to invasion of drilled solids would translate in to enhanced production.
It has been said about MPD (Manage Pressure Drilling) information or UBD (Underbalanced Drilling) reservoir characterization, that it consistently delivers results that are not expected by the petroleum engineering team. Certain fields that had been identified as tight in the reservoir models actually exhibited some of the highest permeability that had been seen in the field. This needs a paradigm shift in the entire approach to oil well drilling. The future of oil well drilling will be less in discovery of new fields but more in terms of enhancing production of existing fields.
This paper will present what UBD could mean for Kuwait Oil Company in terms of strategy for the future. The authors will present the technical feasibility of drilling these wells with the existing technology. The clarion call of the hour is to drill these reservoirs under Managed Pressure or UBD regime. It is for us to heed it and change our future.