宽相对分子质量分布聚合物溶液性能及驱油效果研究

Experimental Study on Performance of Polymer Solution with Broad Molecular Weight Distribution and Flooding Effect

针对油田实际需求,笔者运用仪器分析、物理模拟和油藏工程理论方法,开展了复配聚合物黏度及其影响因素、分子线团尺寸Dh及其分布和驱油效果实验研究,并对复配宽相对分子质量分布聚合物驱提高采收率机理进行了分析。结果表明,对于由"超高分"、"高分"和"中分"等3种聚合物复配而成的宽相对分子质量分布聚合物,随"超高分"聚合物所占比重增大,复配聚合物中分子线团尺寸Dh增大,视黏度增加。与"高分"聚合物相比较,复配聚合物分子线团尺寸Dh分布变宽,抗盐性和抗剪切性增强。物理模拟表明,在聚合物溶液黏度相同条件下,复配聚合物驱增油效果好于"高分"聚合物驱。随复配聚合物中"超高分"聚合物所占比重增加,采收率增幅增加。

In order to meet the practical demand of the field, with the means of the instrumental analysis, physics modeling and the reservoir engineering theory, the viscosity and molecular coil dimension of the compound polymer, obtained by mixing the polymers with different molecular weight of 1400 × 104, 1900 × 104 and 2500 × 104, named as ＂middle molecular＂, ＂high molecular＂ and ＂ultra-high molecular＂, and the oil displacement etticiency were investigated, in addition, the EOR mechanism of the compound polymer was also presented. The results showed that with the proportion of the ＂ultra-high molecular＂ polymer increasing, the molecular coil dimension and the viscosity of the compound polymer increased. Compared to the ＂high molecular＂ polymer, the molecular coil dimension of the compound polymer was broader and the abilities of salinity resistance and shearing resistance was stronger. The physics model experiment indicated that as far as the polymer solution with the same viscosity as was considered, the oil displacement efficiency of the compound polymer solution was better than that of ＂high molecular＂ polymer. The enhancement of oil recovery increased with the proportion of the ＂ultra-high molecular＂ polymer increasing.