三塘湖盆地裂缝性油藏保护储层暂堵技术研究

马朗凹陷是吐哈油田三塘湖盆地的主要产油区,属典型的低渗裂缝性油藏.通过对适合三塘湖盆地马朗凹陷裂缝性油藏使用的复配暂堵钻井液配方的评价,优选出了保护裂缝性储层的复配暂堵型两性离子聚合物钻井液.该体系对裂缝性油藏有较好的保护作用;与原来使用的钻井液相比,API滤失量可降至5 mL以下,岩心的渗透率恢复值提高20%以上,具有良好的保护储层效果.实验表明,复配暂堵型两性离子聚合物钻井液中使用纤维状暂堵剂XWB-1,明显地提高了裂缝性油藏的暂堵效果;该体系具有很强的抑制性,流变性合理,滤失量低,可很好地保护低渗裂缝性油藏,满足现场施工要求.

Study on temporary plugging technology for protecting fracture-type reservoir in Santanghu basin

Reservoir in Maliang sag which is the main oil producing area in Santanghu basin of Tuha oilfield is typical low permeable fracture type reservoir. A compound formulation temporary plugging amphoteric polymer drilling fluid system has been optimized based on the evaluation of compound temporary plugging formulation of drilling fluid which had used in the sag. The system plays a better roll in protecting fracture type reservoir, and comparing with conventional drilling fluid, its API loss filtration could reach 5 mL below and core permeability recovery value could increase by 20%. Experiment showed that the temporary plugging effect for fracture type reservoir has been improved by using the compound formulation temporary plugging amphoteric polymer drilling fluid because fiber shape particle temporary plugging agent XWB 1 has been used in it and field application requirements have been satisfied with the properties of strong inhibition, good rheology and low filtrate.