泥浆地面降温联合隔热钻杆调控特深钻探井筒泥浆温度的分析研究

Analysis of surface drilling fluid cooling combined with insulated drill pipe for wellbore temperature regulation in extra-deep drilling

摘要:

地层超高温是超万米科学钻探面临的核心挑战，针对现有单一降温技术无法满足13000 m井筒控温需求的瓶颈，采用数值模拟方法，以井底泥浆循环温度、井筒泥浆最高温度和出井泥浆温度为评价指标，研究了泥浆地面降温与隔热钻杆联合技术的控温效果。结果表明：在11000~13000 m井段应用泥浆地面降温联合隔热钻杆可将井底泥浆循环温度、井筒泥浆最高温度和出井泥浆温度控制在285、291、63 ℃；增加隔热钻杆的应用长度可有效降低井筒泥浆温度；地温梯度每降低0.1 ℃/100 m，井底泥浆循环温度和井筒泥浆最高温度会同步降低9 ℃。研究表明，泥浆地面降温联合隔热钻杆可将特深钻探井筒关键温度参数控制在安全范围内，这不仅为超万米科学钻探钻井工程设计与科学选址提供重要的理论依据，也为工程顺利实施提供了坚实的技术支撑。

Abstract:

Ultra-high formation temperature poses a core challenge for extra-deep scientific drilling. To address the bottleneck where existing single cooling technologies fail to meet the temperature control requirements of a 13000 m wellbore， this study employs numerical simulation to evaluate the cooling performance of a combined approach integrating surface drilling fluid cooling and insulated drill pipe， with bottom-hole circulating temperature， maximum wellbore drilling fluid temperature， and return drilling fluid temperature as evaluation indices. The results indicate that applying the combined technology from 11000 to 13000 m can control the bottom-hole circulating temperature， maximum wellbore drilling fluid temperature， and outlet drilling fluid temperature at 285 ℃， 291 ℃， and 63 ℃， respectively. Increasing the application length of insulated drill pipes can effectively reduce wellbore drilling fluid temperatures， and for every 0.1 ℃/100 m decrease in geothermal gradient， the bottom-hole circulating temperature and maximum wellbore drilling fluid temperature both decrease by 9 ℃. This research demonstrates that the combined technology can control key temperature parameters within a safe range for extra-deep drilling operations， providing a crucial theoretical basis for drilling engineering design and site selection， and offering technical support for the successful implementation of extra-deep scientific drilling projects.