双河油田注水井酸化解堵研究

Acidizing to Remove Reservoir Plugging in Injection Well in Shuanghe Field

基于双河油田的储层物性特征,通过室内岩心评价实验研究了注水井堵塞机理:注入水中存在大量的固相悬浮颗粒堵塞储层;双河区水敏性矿物含量较高引起粘土膨胀和微粒运移;注入水与地层水不配伍引起结垢降低了储层渗透率。为了解除双河油田注水堵塞,针对注水井堵塞原因,研制了含粘土稳定剂、缓蚀剂、铁离子稳定剂、互溶剂的酸液配方,优化了低伤害酸与土酸结合的复合酸化工艺。物理模拟实验和矿场试验证明了酸液的有效性。

Based on the reservoir character, plugging mechanism of injection wells is studied by laboratory experiment in Shuanghe Oilfield. The formation is jammed by a mass of suspended particle, clay swelling and fine grain escape, and stratum crustation, which can decrease the permeability. In order to release from reservoir choke near injector, acidizing fluid is developed, which contains clay inhibitor, anti-corrosive agent, Fe stabilizer and mutual solvent. At the same time, multiple acidification technique about low damage acid and mud acid is selected based on formation damage mechanism. The acid validity is verified by physics simulation experiment and field test.