杭锦旗区块新型无土相复合盐水钻井液室内研究

Laboratory Research on New Clay-free Compound Salt Water Drilling Fluid in Hangjinqi Block

根据杭锦旗区块水平井对钻井液防塌抑制性和储层保护要求,优化钻井液性能指标,采用有机盐甲酸钠作为密度调节剂,加入无机盐NaCl和KCl,聚阴离子纤维素作为流变调节剂,优选抗盐抑制剂、抗盐降滤失剂、润滑剂等处理剂得到新型无土相复合盐水钻井液配方。通过实验评价,该钻井液抑制性较强,岩样心膨胀率小于15%,岩屑回收率大于90%,具有较好的储层保护性能,储层伤害评价岩心渗透率恢复率大于80%;钻井液性能能够满足杭锦旗区块水平井施工要求。

According to horizontal well drilling fluid inhibitive ability and reservoir protection requirements in Hangjinqi block,a new clay-free compound salt water drilling fluid was developmented by lab experiment,in which sodium formate was used as a density modifier and inorganic salts were added,polyanionic cellulose was used as a rheology modifier,optimization of salt-resisting inhibitor,salt-resisting fluid loss additive,lubricant and other treating chemical.This drilling fluid had good in anti-collapse performance and reservoir protection effect by experimental evaluation,whose core sample expansion ratio was less than 15% and shale recovery ratio was more than 90% and permeability recovery ratio of core was more than 80% by reservoir damage evaluation.The performance of drilling fluid can meet the Horizontal well construction requirements in Hangjinqi block.