改性淀粉聚合物溶液在孔隙介质中的不可入孔隙体积效应  

Inaccessible pore volume effect of modified starch polymer solution in porous media

作　　者：吴天江 

机构地区：[1]长庆油田公司油气工艺技术研究院,陕西西安710018

出　　处：《断块油气田》2010年第6期755-758,共4页Fault-Block Oil & Gas Field

摘　　要：不可入孔隙体积影响聚合物在孔隙介质中的流动性,设计注聚时需考虑不可入孔隙体积效应。实验考察了改性淀粉聚合物溶液通过岩心的IPV值,结果表明,改性淀粉聚合物溶液分子线团最大半径主要分布在0.2～1.2μm,吸附层厚度越大,IPV值就越大。由岩心孔隙分布拟合计算出的IPV值略低于双段塞法的实验值,其原因是部分聚合物分子回旋半径虽然小于孔喉半径,但可能在孔隙外部滞留产生了不可入孔隙体积。不可入孔隙体积的存在主要有2个原因:聚合物溶液分子线团尺寸与岩心孔喉尺寸不完全匹配,聚合物分子线团尺寸越小、孔喉尺寸越大,越利于其通过孔隙喉道,产生的不可入孔隙体积就越小,反之越大;孔隙介质中的边界层效应和聚合物溶液滞留吸附作用,相当于降低了孔喉的有效半径,而增大了IPV值。It is necessary to consider the effect of inaccessible pore volume（IPV） on the fluidity of polymer solution in porous media.This paper analyzes the IPV change of modified starch polymers solution in cores.Experiment result shows that the maximum radius of modified starch polymer molecular coil is chiefly 0.2-1.2 μm.The greater the adsorption layer thickness is,the higher the IPV value is.The fitting calculation value of IPV for pore distribution is slightly lower than that of experiment result in cores.The reason is that although the radius of gyration for partial polymer molecular is smaller than pore throat radius,the external detention of polymer can cause the IPV.Two reasons of IPV existence are mainly as follows： one is the incomplete matching size between polymer molecular coil and pore throat.The smaller the size of polymer molecular coil is and the bigger pore throat size is,the smaller IPV is.The other is that the boundary layer effect of porous media and the detention and absorption of polymer solution are corresponding to decreasing the effective radius of pore throat and increasing the IPV value.

关 键 词：改性淀粉聚合物 吸附 滞留 不可入孔隙体积 

分 类 号：TE357.46[石油与天然气工程—油气田开发工程]