Enhancing Gas Production and Fluid Recovery in Water Sensitive HPHT Sandstone Formation by Using Pre-Pad CO2 Proppant Fracturing Stimulation

Abstract For decades, traditional hydraulic fracturing has played an important role in increasing production from gas reservoirs. Over time, the industry has witnessed substantial innovations in fracturing methodologies, fluids, and techniques. Although CO₂ has proven effective, its deployment in wells have faced challenges stemming from complexities related to foamed fluid rheology and proppant transportation under extreme conditions. Nevertheless, employing pre-pad CO₂ offers a promising solution, mitigating typical formation damage caused by conventional fracturing fluids and facilitating expedited well cleanup. The CO₂ pre-pad followed by conventional proppant fracturing offers a streamlined approach that reduces equipment requirements, resource utilization, and operational intricacy compared to foamed CO₂ fracturing. This methodology provides a viable alternative where foamed fluid systems may be untested or unapproved. By leveraging pre-pad liquid CO₂, operators can accelerate cleanup processes and minimize formation damage relative to conventional cross-linked fluid methods. This paper focus on pre-pad CO₂ technique on a water-sensitive sandstone formation that covers challenges encountered during the design and execution phases, highlighting valuable lesson learned from the experience. Adopting the pre-pad CO₂ strategy holds promise for significantly reducing operational timelines and expenditures. Pumping pre-pad CO₂ not only boosts well productivity but also simplifies operations, overcome temperature constraints, and reduces the risks associated with screened-out fractures, thus offering a compelling advantage over traditional foamed proppant fracture treatments. In a remarkable turnaround, this innovative technique unlocked wells and gained gas that cannot be stimulated at conventional proppant fracturing. Through the strategic deployment of a single-stage pre-pad CO₂ treatment, followed with well-designed conventional proppant fracture within the same formation, the well was recovered and restored to commercially viable production levels. The simplicity and effectiveness of this approach make it particularly suitable for formations where foamed fluid systems remain untested. Furthermore, the reduced equipment footprint and cost compared to foamed CO₂ treatments highlight its operational efficiency and economic viability.