硅酸盐／聚乙烯醇抑制性能研究

摘要

Potassium silicate/polyvinyl alcohol inhibitor was selected to protect the borehole instability in foam drilling ,and its inhibitive properties were evaluated by means of shale self-priming experiment ,mud-making inhibition of bentonite ,rolling recovery experiment and hard-ness test . The results indicate that potassium silicate/polyvinyl alcohol has a good inhibitive properties .Finally ,the inhibition mechanism of the inhibitor was studied by XRD .The results showed that the strong inhibition of potassium silicate/polyvinyl alcohol to the shale is derived from the synergies of potassium silicate and polyvinyl alcohol ,in which sealing property and film-forming ability are the major factors to maintain borehole stability .%针对泡沫钻井井壁失稳问题，优选了硅酸钾/聚乙烯醇作为抑制剂。通过泥页岩自吸、抑制膨润土造浆、滚动回收和硬度测试等实验，评价了其抑制性能。实验结果表明硅酸钾/聚乙烯醇具有良好的抑制特性。借助XRD分析，研究了硅酸钾/聚乙烯醇的强抑制作用机理。研究表明，硅酸钾/聚乙烯醇对泥页岩的强抑制性来源于硅酸钾与聚乙烯醇两者相协同作用的结果，其中封堵性与成膜性是其维持井壁稳定的主要因素。