摘要
在潮湿的环境下,油气构造中富含的CO2对水泥石产生碳化腐蚀,使水泥石渗透率变大、抗压强度降低,诱发流体窜流、塑性地层井壁坍塌等事故,造成很大的经济损失。分析认为,CO2腐蚀水泥石的机理主要有淋滤作用、溶蚀作用、碳化收缩作用和高矿化度地层水的协同作用。通过CO2腐蚀水泥石的试验得知:时间越长,腐蚀深度越深;压力越高,腐蚀速度越快;在压力相同的情况下,温度越高,腐蚀速度越慢。根据CO2腐蚀水泥石速度的主要影响因素,指出了水泥石抗CO2腐蚀的技术原理,并提出了提高水泥石抗CO2腐蚀的方法。
Under a wet environment, the carbon dioxide in pay zones caused carbonized corrosion to the cement stone. Therefore the permeability of cement stone increased and the compressive strength decreased resulting in the fluid channeling, borehole wall sloughs in plastic formations and huge economic loss. The mechanism of carbonized corrosion to the cement stone includes leaching effect, denudation, carbonization contract, and synergetic effect of formation fluids with high mineral concentration after analysis. The experiments show that the longer the corrosion time, the deeper the corrosion; the higher the pressure, the higher the corrosion speed; under the same pressure, the higher the temperature, the lower the corrosion speed. Based on the main parameters impacting the carbonized corrosion to the cement stone, the principles of anti-corrosion and the methods to improve anti-corrosion were provided.
出处
《石油钻探技术》
CAS
北大核心
2008年第2期42-44,共3页
Petroleum Drilling Techniques
基金
中国石油天然气集团公司应用基础研究计划“高含硫气藏安全开发基础理论研究”(编号:06A100101)部分内容
关键词
CO2
水泥石
腐蚀
腐蚀试验
防腐
carbon dioxide
cement sheath
corrosion
corrosion test
corrosion control
