高温油藏弱凝胶深部调驱技术室内研究

Experimental Study on Profile Control of Weak Gelling Deep Displacement in High Temperature Reservoirs

针对高温油藏特点,采用非离子聚丙烯酰胺与甲醛和苯酚进行了地层条件下的成胶性能研究。结果表明,该体系成胶时间长,在30h后开始大量成胶,苯酚与甲醛比例的增加有利于羟甲基苯酚的生成,交联剂和非离子聚丙烯酰胺含量的增加有利于体系成胶。综合考虑成本,采用苯酚与甲醛比例为1∶2,交联剂浓度为1200mg/L,非离子聚丙烯酰胺2000mg/L。最后通过并联驱替模拟试验表明,该弱凝胶能使后续水驱转向,提高低渗透油层的采收率。

In allusion to the characteristics of high temperature reservoirs,nonionic polyacrylamide was used to react with formaldehyde and phenol form weak gel.The experiment result shows that gelling of the system needs a long time of more than 30 hours,the ratio of phenol and formaldehyde increase is beneficial for hydroxymethylphenol,the increase of proportion of crosslinking agent and nonionic polyacrylamide is beneficial for gelling.The oil displacement profile control agent is composed of crosslinking-agent of 1200mg/L (ratio of phenol and formaldehyde is 1∶2),nonionic polyacrylamide of 2000mg/L.The result of the experiment shows that the weak gel can divert the following fluids and enhance the oil recovery percent in low permeability reservoirs.