适用于硅质材料减轻水泥浆的缓凝剂研究

Research on retarder for cement slurry with siliceous extender

针对以硅质材料为减轻剂的大水灰比水泥浆在温度大于50℃时稠化曲线出现“包心”、“鼓包”、“台阶”等异常胶凝现象,采用小分子羧酸盐复配得到一种缓凝剂C-R23L,并对其稠化性能及水泥浆的综合性能进行了评价。实验结果表明,加有C-R23L的水泥浆在50~130℃时,稠化时间可调、稠化曲线正常,可有效抑制“包心”、“鼓包”、“台阶”等异常现象的发生,综合性能良好。C-R23L在南海东部某井中进行了现场应用,固井质量优质。该缓凝剂的研制有效拓宽了以硅质材料为减轻剂的低密度水泥浆的适用范围,为该类水泥浆体系的应用提供了新思路。

In view of the abnormal gelation phenomenon of"core wrapping","bulge wrapping"and"step"in the slurry using siliceous material as lightening agent when the temperature is higher than 50℃,a retarder C-R23L consist of carboxylate compound was obtained and evaluated.The experimental results show that the thickening time of cement slurry is adjustable and the thickening curve is normal at 50~130℃,which can effectively inhibit the occurrence of abnormal phenomena such as"core","bulge wrapping"and"step".C-R23L has been applied in a well in the east South China Sea,and the cementing quality is excellent.The development of the retarder effectively broadens the application scope of low density cement slurry with siliceous material as lightening agent,and provides a new idea for the application of this kind of cement slurry.