H1块聚驱后弱凝胶调驱配方体系研究

发布时间：2018-07-16 19:35

【摘要】：针对H1区块高温、高渗、大孔道的地层特点及聚合物驱后出现水窜、无效水循环等,开展了弱凝胶体系配方研制,通过成胶特性、稳定性、粘弹性、流变性等参数,确定了最佳配方。并对影响配方成胶性的因素进行测定,主要有配制水中溶解氧含量、细菌含量、不溶悬浮物含量及金属离子等。配方成胶时间为在70℃状态下10小时开始成胶,900小时后开始破胶,21小时粘度达到最大值32000 mPa.s,100小时后调剖剂强度趋于稳定,粘度保持在11000-13000mPa.s;弹性模量及粘性模量适中,溶液形变过程中能量储存较好;当溶解氧含量接近时1.5mg/L弱凝胶溶液成胶效果差、强度低、破胶时间快,含氧量为7mg/L时弱凝胶调驱体系达到最佳效果;细菌会对弱凝胶体系产生强烈降解作用,当细菌含量为1000个/mL时,溶液粘度相对于无菌样品下降幅度为15%;60mg/L不溶悬浮物含量对弱凝胶影响最大,溶液配置仅6天即完全破胶;三价铁离子对弱凝胶无影响;二价铁离子会严重降解弱凝胶,当Fe2+质量浓度为5mg/L时,弱凝胶溶液粘度损失率约为5%,随着Fe2+质量浓度的增高,弱凝胶粘度急剧下降。文章最后对配方进行模拟地层的岩心实验,测定弱凝胶溶液对不同渗透率岩心的封堵性、压力梯度、分流率及最佳注入段塞等。弱凝胶配方3对模拟地层的提高采收率性能均较好,压力梯度为24 MPa/m,当弱凝胶注入量为0.2PV时采收率可提高19.06%,而超过0.2PV注入量后提高采收率效果提升甚微。
[Abstract]:In view of the stratigraphic characteristics of high temperature, high permeability, large pore channel, water channeling after polymer flooding and ineffective water circulation in H1 block, the formulation of weak gel system was developed, and the parameters such as gelation characteristics, stability, viscoelasticity, rheology and so on were carried out. The best formula was determined. The factors affecting the gelling property of the formulation were determined, including dissolved oxygen content, bacterial content, insoluble suspended matter content and metal ions in the prepared water. The gelation time of the formula is that at 70 鈩，

本文编号：2127452