The treatment of produced water, associated with oil & gas production, is envisioned to gain more significant attention in the coming years due to increasing energy demand and growing interests to promote sustainable developments. This review presents innovative practical solutions for oil/water separation, desalination, and purification of polluted water sources using a combination of porous membranes and plasma treatment technologies. Both these technologies can be used to treat produced water separately, but their combination results in a significant synergistic impact. The membranes functionalized by plasma show a remarkable increase in their efficiency characterized by enhanced oil rejection capability and reusability, while plasma treatment of water combined with membranes and/or adsorbents could be used to soften water and achieve high purity.

Zonal isolation and cement sheath integrity are vital for a consistent oil and gas production process in an economic and environmentally conscious manner. However, cement is a brittle material that can fail under repeated application of stresses. The objective of this research is developing a novel material Complex micro-containers (CMC) to induce autonomous self-healing properties to the cement using the mechanism of a self-expanding polyurethane foam formation in a crack area. Complex micro-containers (CMC) consist of polyol-loaded polyurea (PUa) micro- and nanocapsules loaded inside the isocyanate-filled core of larger polyurethane (PU) microcapsules. The method of CMC creation includes several steps. During the first step, an oil-in-oil emulsion, composed of organic solvent and polyol-polyamine solution, is created. The second step is made of a polyurea shell formation directly at the surface of the polyol droplets controlled by an addition of isocyanate. As the result of the interfacial polymerization process, micro- and nanocapsules are formed. Then, they are mixed with the isocyanate solution and further emulsified in the water-based media. The droplets of isocyanate with micro- and nanocapsules are encapsulated through polyurethane shell formation by adding polyol. A variety of factors alter the morphology and size of the micro- and nanocapsules including parameters of emulsion's creation, core/shell ratio, and dispersion speed. The optimal content of isocyanate and polyols in cores of polyurea and polyurethane microcapsules, mechanical mixing parameters, and concentration of emulsifiers in oil-in-oil and oil-in-water emulsions were determined. FTIR-spectroscopy was used to identify the chemical structure and to demonstrate encapsulation of the isocyanate core and the polyurethane shell and the polyol core and polyurea shells. TGA-analysis, optical microscopy, and scanning electron microscopy methods were used to determine the core content of micro- and nanocapsules and their size. The peeling strength test proved that the release of the microcapsules’ core content occurs by pressure application and the diisocyanate reacts with polyol and water and creates the polyurethane material. The main advantage of CMC is its expandable properties due to the formation of a polyurethane foam in the presence of water that can effectively fill the micro-cracks directly in a place of cement breakage. Integration of developed new material into the cement body will allow for improving a long-term wellbore isolation and mitigating a leakage potential in the cemented annuli.

Produced water is by far the largest by product by volume associated with oil and gas production. To minimize environmental impact of the produced water disposal, reuse produced water, and fulfill the targeted Zero-Liquid-Discharge approach, it is necessary to develop new economically viable technologies for water purification. The objectives of the research enclose development of the sustainable ion-exchange resin from the discarded expanded polystyrene via a multi-stage process with plasma treatment. The process of sustainable ion-exchange resins’ preparation includes several consecutive steps. At first, a polystyrene waste is collected and dissolved in an organic solvent.After that the polymeric beads are prepared using a microdroplet precipitation mechanism. Then, one part of the polystyrene beads is modified with the green gas-liquid interfacial plasma (GLIP) sulfonation process producing a strong acidic cation exchange resin. The other part is functionalized by amine groups in cyclopropylamine medium producing strong basic anion exchange resin. Robust and self-sustained process for creating the polystyrene beads was developedusing the «solvent-non-solvent» system. The bead formation process is realized by a controlled, laminar liquid jet broken into equally sized beads by vibrations at optimized frequency value. This process was performed using the in-house state-of-the-art encapsulator instrument. The concentration of waste expanded polystyrene and a filler in a solution was optimized. The size of obtained porous beads was measure around 750-1000 micron and can be controlled by the nozzle size and frequency of vibration. The research describes a new method of sustainable ion-exchange resin creation. The utilization of this novel material is a beneficial approach to re-use plastic waste and reuse it to clean produced water from dissolved salts. Moreover, plasma technology that is used for polystyrene treatment is probably the most versatile surface treatment technique and, moreover, it is environmentally friendly.

Advancing the materials used in oil drilling and production has significantly augmented the industry’s efforts to improving the processes and preventing the operations failures. Presently, oil drilling and production demand that materials do not simply demonstrate better performance, but also possess some degree of intelligence. The intelligence is induced to the materials by preprogramming a certain response to a change in the surrounding conditions to trigger the function of the used materials. This improves the performance and prevents possible physical damage or mitigates negative changes in the downhole environment during production. Smart responsive microcapsules, with the ability to self-heal the materials, delayed and targeted active release, and could become a viable solution for the challenges the oil drilling and production industry is currently facing. This paper provides an overview of the benefits that a microencapsulation technique has demonstrated when applied to the materials involved in oil drilling and production. It outlines possibilities for improving the well drilling process when products containing microcapsules are applied. Several examples demonstrating the ability to perform downhole treatment seamlessly with pre-designed microcapsules are embedded. The paper puts emphasis on developing smart self-healing materials by integrating microcapsules into the cement sheath as well as the coatings of steel pipes to mitigate costly failures. Finally, the paper shows examples of some outstanding results of microencapsulated materials when applied to the most advanced research areas in the oil industry such as enhanced oil recovery (EOR) and hydraulic fracturing.

Materials used in the oil and gas industry are required to possess resilient properties to sustain operational challenges. These include high pressures and temperatures of the working fluids created by both reservoir depths and compressors combined with the inherent aggressive and corrosive components. Multiple solutions have been introduced to the industry to minimize corrosion probability in recent years. Utilizing external and internal tubular non-metallic coating as well as switching to the products entirely made of the non-metallic composites are the most commonly used and best performing solutions. This paper presents a comprehensive overview of the advances of the most promising research and development activities in the area of protective coatings as well as non-metallic composite material products with real case studies in downhole applications. Special emphases are put on the most promising technological breakthroughs such as 3D printing with non-metallic composites containing nano-sized short fibers and continuous nanofibers, which could be potentially used in the fabrication of future downhole composite products. The breakthrough solutions in composite technologies such as self-healing systems, including capsule-based, fiber-based and vascular healing network, which are perfectly aligned with the 4th Industrial Revolution are also described.