World's First Coiled Tubing Electric Inflatable Packer Deployment of a Fully Hybrid Optical/Electrical Activated Multi-Set Inflatable Element for Selective Acidizing. A Case Study from Iraq

Abstract

Inflatable packers have been the preferred technique for the selective placement of chemical treatments in a wellbore with Coiled Tubing (CT). Traditionally, these have come with some limitations, such as power supply, Real-Time (RT) positioning, surface control, differential pressure activation, ball drop setting, tension, reciprocating set systems, and the ability to quickly change the tool flow path based on treatment response. This paper discusses the first electrically controlled packer implementation that drastically improved operational efficiency in Iraq. This case relates to a mature field in Iraq where precise selective acidization of vuggy carbonate zones with high permeability contrasts was required. The operation was carried out successfully with an electrically controlled packer suitable for acid that provided real-time downhole insight to improve the decision-making process and a precise, flawless acidizing operation. Additionally, the electric actuation system enabled independent control of the flow path position throughout the operation, allowing fluid injection above or below the element to suit the requirements of the operation as needed. The unique solution provided in this paper confirms the benefits of customizing fiber optic and electric technology with an inflatable packer to accurately place the element and selectively stimulate zones with high permeability contrast. A RT downhole sensor module also provides critical information to ensure the operation is carried out as intended. The particular sensors that helped carry out this operation included the Casing Collar Locator (CCL) and Gamma-Ray (GR) to correlate depth, internal and external temperatures, a load module, and internal and external pressure measurements to precisely position the packer in between two layers of a narrow interval without exceeding either the reservoir frac pressure or the packer element differential pressure. This revolutionary technique was successfully implemented on an injection well, saving more than 24 hours of intervention time and allowing early injection to reduce costs for the customer. The CT Electric Inflatable Packer (EIP) enabled the splitting of the operation into two treatments, above and below the packer, during the same run. The approach to this intervention increased operational efficiency while reducing waste to optimize the overall well intervention cost with RT data. This paper describes how a new versatile EIP technology can improve operational efficiency and reduce non-productive time on various applications, such as selective treatments, multiple selective acidizing of sleeves, clusters, intervals, water shut off with sealant fluids, or chemical sand consolation with resins.