Efficient plugging of leaky wells using nano-additive enhanced barrier materials

Oil and gas wells need robust plugging and abandonment as they reach the end of their productivity. However, the harsh subsurface conditions like high temperatures, pressures and abnormal chemical conditions like low pH pose a challenge to current day plugging materials. Most of them result in formation of leakage pathways in the barrier material either by fractures or debonding between the casing and formation and/or cement. These leakage pathways result in macro-scale effects like pollution disrupting the environment. These challenges could be overcome by understanding the failures and their origin and design materials accordingly to prevent them. In order to achieve durable barrier materials, one important consideration is that the material should be compatible with the natural formation rocks and the natural fluids present. Research has been directed towards studying the compositions and characteristics of natural formation materials in order to design a similar barrier material. One advancement in the design of these materials had been the introduction of Nature based nano-material additives in barrier materials which were shown to have a substantial impact in the betterment of their physical and chemical characteristics. Engineering these hydraulic barrier materials happens in a much shorter time scale compared to naturally engineered formation rocks and has a lot of potential and scope in the future design of barrier materials and is hence the chief focus of our research. Another area to be explored in this research is how nature can heal the faults in natural formations which provide insight into creating self-healing barrier materials.