【摘要】：針對H1區(qū)塊高溫、高滲、大孔道的地層特點(diǎn)及聚合物驅(qū)后出現(xiàn)水竄、無效水循環(huán)等,開展了弱凝膠體系配方研制,通過成膠特性、穩(wěn)定性、粘彈性、流變性等參數(shù),確定了最佳配方。并對影響配方成膠性的因素進(jìn)行測定,主要有配制水中溶解氧含量、細(xì)菌含量、不溶懸浮物含量及金屬離子等。配方成膠時(shí)間為在70℃狀態(tài)下10小時(shí)開始成膠,900小時(shí)后開始破膠,21小時(shí)粘度達(dá)到最大值32000 mPa.s,100小時(shí)后調(diào)剖劑強(qiáng)度趨于穩(wěn)定,粘度保持在11000-13000mPa.s;彈性模量及粘性模量適中,溶液形變過程中能量儲存較好;當(dāng)溶解氧含量接近時(shí)1.5mg/L弱凝膠溶液成膠效果差、強(qiáng)度低、破膠時(shí)間快,含氧量為7mg/L時(shí)弱凝膠調(diào)驅(qū)體系達(dá)到最佳效果;細(xì)菌會(huì)對弱凝膠體系產(chǎn)生強(qiáng)烈降解作用,當(dāng)細(xì)菌含量為1000個(gè)/mL時(shí),溶液粘度相對于無菌樣品下降幅度為15%;60mg/L不溶懸浮物含量對弱凝膠影響最大,溶液配置僅6天即完全破膠;三價(jià)鐵離子對弱凝膠無影響;二價(jià)鐵離子會(huì)嚴(yán)重降解弱凝膠,當(dāng)Fe2+質(zhì)量濃度為5mg/L時(shí),弱凝膠溶液粘度損失率約為5%,隨著Fe2+質(zhì)量濃度的增高,弱凝膠粘度急劇下降。文章最后對配方進(jìn)行模擬地層的巖心實(shí)驗(yàn),測定弱凝膠溶液對不同滲透率巖心的封堵性、壓力梯度、分流率及最佳注入段塞等。弱凝膠配方3對模擬地層的提高采收率性能均較好,壓力梯度為24 MPa/m,當(dāng)弱凝膠注入量為0.2PV時(shí)采收率可提高19.06%,而超過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，

本文編號：2127452