Enriching Productivity by Using Organophilic Clay-Free Reservoir Drilling Fluid Technology on Tight Reservoirs

Maximizing asset value is one of several drilling challenges in super-tight reservoir fields. This paper presents the methodology for developing Drill-In Organophilic Clay-Free (DIOCF) invert emulsion fluid technology that enhances well production through fundamental geological studies and fluid testing. It is a success story that resulted in significant accomplishments. Precise quantitative and qualitative analytical methods granted milestone results. Design phases for the drilling fluid began with geological studies of the natural core, including computed tomography (CT scan) and high-resolution imaging, which was used to qualify the core samples. Standard drilling fluid and return permeability tests were then completed by stressing the fluid beyond the normal upstream conditions. Optimizing the proposed fluids against the original core gave the operator the projections required to drill super-tight reservoir wells. From planning to execution, valuable observations were recorded. Using a customized DIOCF system resulted in successfully drilling and completing substantially tight permeability reservoirs. Only seven days of drilling time were required to drill this section, saving eighteen days of authorization for expenditure (AFE) time. No critical path of time was wasted because of uncertainty or changes to the approved plan. As a result of using a fit-for-purpose fluid, the actual Equivalent Circulating Density (ECD) was 0.03 specific gravity (SG) lower than that previously experienced with a conventional fluid. As reported in the offset wells, the recorded reduction in ECD resulted in a two-thirds reduction in induced downhole losses. Significantly, on this promising profile, the productivity recorded was 250 percent higher than expected, with a negligible skin damage value. The significant savings in AFE days were due to a four times faster rate of penetration (ROP), alongside reasonable control over ECD; both factors contributed to lowering the overall well's total cost of ownership. The invaluable increase in well production has encouraged the operator to apply the same procedures in all the tight reservoir sections on the same campaign and nationwide.