Abstract
Chemical stimulation has a strong track record of production improvement, and has always adapted to suit ever new environments, regulations and scenarios. From early arsenic based chemical techniques, the approaches have moved on and matured to HF and HCl solutions, and more recently with environmentally friendly additives. However, the pendulum continues to move and due to an increasing impact of conventional acid systems on ageing production infrastructure, facilities and pipelines as well as an inability to commercially support independent intervention and/or flow-back, even these systems are sometimes considered unacceptable.
Fortunately, the industry is now in the privileged position of being able to address these issues, it simply does not yet appear to have fully appreciated this widely. All too often stimulation interventions are reasonably justified on the basis of poor well performance; only to be disregarded when it becomes clear that simplistic deployment and flow-back are not considered available options, due to corrosive stimulation fluid behaviour. However, more recently synthetic acid formulations have removed the majority of these concerns; with neutral pH, inert corrosion behaviour and environmentally acceptable chemistry, they are the ideal answer to the range of issues that have mounted over recent years.
This paper will demonstrate that the oilfield has recently developed the necessary solutions, that when combined together provide for a low cost, environmentally friendly, low impact, integrity aligned approach to well stimulation operations under the majority of conditions. Certainly requiring a multi-disciplinary deployment approach, these new chemistries and methodologies offer the very tantalising prospect of a reinvigorated chemical stimulation business, particularly in mature/high-cost/remote basins. With case histories, process considerations and holistic intervention considerations; the paper will demonstrate the extensive opportunity that is currently simply waiting to be accessed by these techniques throughout the brownfield environment. No longer referred to as "acid treatments", these twenty-first century approaches to stimulation, offer the industry the unique potential to redefine and reclassify the delivery from these operations.
Maximising recovery from existing assets is heavily relied upon in annual wellwork; particularly in challenging commercial environments. While wellbore stimulation can deliver this, historically, the percentage of delivery from intervention has reduced, due to increasing issues related to environmental, integrity and commercial challenges. The deployment of synthetic acids as environmentally, integrity and commercially attractive solutions; offers an opportunity for a complete revitalization of chemical stimulation in mature and commercially challenged basins.
