高温高密度水基钻井液体系的研究及应用

Research and Application of High-temperature and High-density Water-based Drilling Fluid System

在四川泸州区块,由于地层压力高、地层温度梯度高、气层埋藏深,导致该地区井底温度高、密度高,为节省成本直井段均为水基钻井液钻进,但以往的水基钻井液无法满足该地区要求,为解决该问题,基于前期的实验通过正交实验,研究出一种高温高密度水基钻井液体系配方。该体系在1.6~2.2 g/cm^(3)均具有良好的携带岩屑的能力和良好的封堵孔隙的能力;具有良好的抑制性、强的润滑性、良好的封堵性和较好的抗温能力;抗岩屑污染能力达到8%。该体系在泸203H123平台成功应用,钻井液性能稳定、井壁稳定、携砂正常、起下钻摩阻小,表现出了优良的性能。

In the Luzhou block of Sichuan Province,due to high formation pressure,high formation temperature gradient,and deep gas reservoir burial,the bottom hole temperature and density in the area are high.In order to save costs,water-based drilling fluid is used for drilling straight sections.However,previous water-based drilling fluids cannot meet the requirements of the area.To solve this problem,based on previous experiments and orthogonal experiments,the author has developed a high-temperature and high-density water-based drilling fluid system formula.The system has good ability to carry rock debris and seal pores in the range of 1.6~2.2 g/cm^(3) has good inhibitory properties,strong lubricity,good sealing properties,and good temperature resistance.The ability to resist rock debris pollution reaches 8%.This system has been successfully applied on the Lu 203H123 platform,with stable drilling fluid performance,wellbore stability,normal sand carrying,and low friction during tripping,demonstrating excellent performance.