Petroleum Exploration and Development (Oct 2022)
Research progress and development direction of low-temperature drilling fluid for Antarctic region
Abstract
By combing the characteristics of drilling in Antarctic region, performance requirements on drilling fluid for Antarctic low temperature conditions, and research progress of low temperature drilling fluid, current problems of the drilling fluid have been sorted out, and the development direction of the drilling fluid has been pointed out. Drilling in the Antarctic region mainly includes drilling in snow, ice and subglacial rock formations, and drilling in Antarctic low temperature conditions will face problems in four aspects: (1) low temperature and large temperature changes in the drilling area; (2) likely well leakage and drillstring-sticking in the snow layer, creep in the ice layer, ice chip gathering jamming in the warm ice layer, well wall collapse in the subglacial rock formations; (3) lack of infrastructure and difficulty in logistical support; (4) fragile environment and low carrying capacity. After years of development, progresses have been made on low-temperature drilling fluids for the Antarctic region. Low-temperature petroleum-based drilling fluid, ethanol/ethylene glycol-based drilling fluid, ester-based drilling fluid and silicone oil-based drilling fluid have been developed. However, these drilling fluids have problems such as insufficient low-temperature tolerance, low environmental performance and weak wellbore stability, etc. In order to meet the performance requirements of drilling fluid under low-temperature conditions in Antarctic region, the working mechanisms of low-temperature drilling fluid must be examined in depth; environment-friendly low-temperature base fluid of drilling fluid and related additives must be developed to prepare environmentally friendly low temperature drilling fluid systems; multi-functional integrated adjustment method for drilling fluid must be worked out to ensure well wall stability and improve cutting-carry capacity when drilling ice formations and ice-rock interlayers; and on-site support operation codes must be established to provide technical support for Antarctic drilling.
