高密度高炉矿渣水泥浆固井技术研究

Study of High-density Blast Furnace Slag(BFS) Slurry

以低密度矿渣水泥浆研究结果为基础 ,设计高密度水泥浆 ,使油气井全井段使用矿渣水泥浆固井 ,以提高固井质量 ,降低固井成本 .以高炉矿渣为水化胶凝材料 ,添加少量水泥和碱性激活剂 ,结合 MTC固井技术和多功能钻井液固井技术 ,设计密度 1 .75～ 1 .93 g/cm3 的矿渣水泥浆、矿渣MTC浆和矿渣 UF浆 .对 3种高密度矿渣水泥浆在 45～ 75℃条件下水泥石的抗压强度 ,水泥浆的凝结时间、流变性和稳定性进行试验对比 .试验结果表明 :3种水泥浆水泥石抗压强度从大到小依次为 :矿渣 UF浆 ,矿渣 MTC浆 ,矿渣水泥浆 .3种体系水泥石抗压强度满足油气井井下射孔作业对水泥石抗压强度的要求 .在 45～ 75℃条件下 ,随着温度的升高 ,高密度矿渣水泥浆和矿渣 UF浆水泥石抗压强度呈降低趋势 .矿渣 MTC浆和矿渣 UF浆的流变性。

Cementing well by using slag slurry in whole length can improve the quality of well cementing and reduce the cost of it. Based on MTC cementing well technique, universal drilling fluid cementing technology and the study of low density slag slurry, three high density BFS slurries were developed. They are called as BFS cement slurry, BFS MTC cement slurry, and BFS UF cement slurry separately. In the slurry system, BFS was used as hydration gelling material, a little amount of cement and alkalic activator was added. The density of three slurries in the range of 1.75~1.93g/cm 3. The setting time, rheology and stability of them, and their compression strength after setting were measured. The results show that, the order of their compression strength from high to low is BFS UF, BFS MTC and BFS. The strength can meet the need of downhole perforating operation. The rheology, stability and thickening time of BFS MTC slurry and BFS UF slurry can be changed by adding different kind and amount of drilling fluid.