聚合盐钻井液体系研究

针对北80井区强水敏储层及使用白油基钻井液成本高的问题，开展了具有强抑制性及良好封堵能力的水基钻井液体系研究。通过对聚合盐JN（胶体，干基的有效浓度为25％）性能评价，确定聚合盐在钻井液中的加量为40％，并优选了与之配伍的处理剂，形成了一套性能优良的聚合盐钻井液体系。室内评价结果表明，聚合盐钻井液的储层渗透率恢复值高于柴油基钻井液，略低于白油基钻井液，可满足北80井区储层保护要求。聚合盐钻井液具有较强的抑制性和滤失造壁性，流变性易调控，润滑性、抗温性及抗污染能力较强，其抑制效果和储层保护效果与油基钻井液基本相当，可满足北80井区强水敏储层钻井施工要求。

Researches on Polyelectrolyte Drilling Fluids

Research was done on an inhibitive water base mud with good sealing capacity to replace the expensive white oil base mud used in the Bei 80 area,in which the reservoir is strongly water sensitive.A polyelectrolyte was selected to use in 40% with other compatible additives,and a set of water base muds with excellent mud properties was developed.Laboratory research shows that reservoirs drilled with polyelectrolyte mud have permeability recovery even higher than that of reservoirs drilled diesel oil base muds,only slightly less than that of reservoirs drilled with white oil base muds.Polyelectrolyte mud has strong inhibition and good mud cake forming ability.The Rheology of the mud is easy to control.This mud also has good contamination resistence,and can be used at elevated temperatures.It is comparable with oil base muds in hale inhibition and reservoir protection,and can satisfy the needs for drilling in Bei 80 area.