淀粉接枝共聚物在多孔介质内成胶效果实验——以渤海油田SZ36-1油藏条件为例

Experiments on the gelling effect of amylum graft copolymer in porous medium:a case study on SZ36-1 oil reservoir in Bohai Oilfield

淀粉接枝共聚物凝胶由于其成胶强度大、成本低、成胶时间可控等优点已经在我国部分油田应用。然而现今针对淀粉接枝共聚物凝胶的研究多集中在合成方法、性能表征和常规方法的成胶强度研究上,结合现场实际情况,尤其是海上油田现场实际情况的成胶效果研究较少。以渤海油田SZ36-1油藏条件为例,研究了淀粉接枝共聚物凝胶在接近油藏实际条件的多孔介质中的成胶效果。结果表明,在玻璃容器内具有良好耐稀释性、抗剪切性、耐油性、耐黏土性和时间稳定性的淀粉接枝共聚物体系,在岩心孔隙内却难以发生交联反应。由此可见,化学反应空间环境对淀粉接枝共聚物成胶效果存在较大影响,空间尺寸越大,成胶效果越好。为增加淀粉接枝共聚物各组成在孔隙内发生碰撞概率即提高成胶效果,需要适当提高常规优化配方中各组分浓度。

Amylum graft copolymer gel has been applied to the construction of some oilfelds in China owing to its advantages of high gelling strength, low cost and controllable gelling time. At present, the researches on amylum graft copolymer gel mostly focus on generation methods, property characterization and gelling strength of conventional methods. However, the gelling effect is less re-searched based on the actual feld conditions, especially the actual situations of offshore oilfelds. In this paper, SZ36-1 oil reservoir in Bohai Oilfeld was taken as the example to investigate the gelling effect of amylum graft copolymer gel in the porous medium which is similar with the actual oil reservoir condition. It is shown that the amylum graft copolymer system which displays the good properties of dilution resistance, shear resistance, oil resistance, clay resistance and time stability in glass containers cannot present crosslinking reaction easily in the pores of cores. It is indicated that the gelling effect of amylum graft copolymer is affected more by the space envi-ronment of chemical reaction. And the larger the space is, the better the gelling effect is. In order to increase the collision probability of compositions of amylum graft copolymer, i.e., to improve the gelling effect, it is necessary to increase appropriately the compositional concentration of conventional optimized formula.