杏13区块三类油层聚合物吸附特性及其驱油实验研究

杏13区块三类油层在实施聚合物驱油时,研究聚合物在油藏孔隙中的吸附滞留情况及对驱油效果的影响。通过室内油砂吸附性实验及岩芯驱替实验,对相对分子质量为700×104抗盐聚合物、相对分子质量为1 800×104和2 500×104进行不同层位不同质量浓度的聚合物吸附研究及其驱油效果对比。结果表明,在三类油层上,不同相对分子质量的聚合物在油砂上的吸附量不同;不同质量浓度的聚合物溶液吸附损失对聚合物溶液的黏度影响不同;在相同质量浓度下,相对分子质量为700×104抗盐聚合物和2 500×104聚合物在水驱基础上化学驱采出程度在11%~14%;相对分子质量1 800×104聚合物水驱基础上化学驱采出程度在10%~12%。

Experimental Study on Polymer Flooding and Its Adsorption Properties in Xing 1 3 Block of Class III Reservoir

Adsorption and retention of the polymer in reservoir pore as well as the effects on oil displacement efficiency arestudied when polymer flooding is used in class III reservoir of Xing 1 3 block.In order to compare the displacement effect, sand adsorption experiments and core displacement experiments are carried out to study the adsorption condition of salt-resistant polymer （relative molecular mass 700×104 ）and two other polymer （relative molecular mass 1 800×104 and 2 500× 104 ）in different horizon and concentration.The results show that in Class III reservoir,the adsorption quantity of the polymers with different relative molecular mass in the sand is different.The adsorption loss of the polymer with different concentration has different effect on the viscosity.On the condition of the same concentration,the chemical flooding recovery degree by the salt resistant polymer （relative molecular mass of 700×104）and the polymer （relative molecular mass of 2 500×104）can reach 11%-14% based on the water flooding.While the recovery degree by the polymer （relative molecular mass of 1 800× 104 ）can only be 10%-12%.