Abstract:
The Arctic area is rich in oil and gas resources. However, its geological and environmental factors such as low temperature, shallow hazards, permafrost and extreme temperature change in wellbore bring many challenges to drilling operation. For this reason, during the "Thirteenth Five-Year Plan" period, Sinopec took safety, environmental protection and efficient drilling as its overall goals and focused on solving the problem of "cold" adaptability of drilling equipments and tools, drilling technologies and measures, wellbore working fluids. Research was performed on key technologies regarding drilling hazard assessment and control, environmental protection, key drilling equipments and tools, drilling techniques, wellbore working fluids, etc. Impressive progresses were made in the quantitative risk assessment method for hazards to shallow gas and gas hydrate formations, the orbital drilling rigs and tools utilized at −50 °C, stability evaluation and borehole stability control in permafrost, and engineering technologies related to drilling fluid and cement slurry under low temperature conditions. As a result, the key technology system of drilling in the Arctic sea was preliminarily developed. As the Arctic oil and gas development enters higher latitudes and thicker permafrost regions on land, and the oceans will advance to deeper waters, perennial ice or thicker ice floes, drilling in Arctic sea will face greater challenges and requires further progress. Therefore, it is necessary to build a complete drilling and completion technology system in the Arctic sea by improving the theories and methods and developing new key equipments and tools. With the system, the demands of efficient exploration and development of oil and gas reservoirs in the Arctic region can be realized, thereby enhancing the economic benefits and core competitiveness of China’s oil companies in international cooperation projects of oil and gas development in this area.