裂缝型凝析气藏调剖剂成胶性能的影响因素

Influential factors on gelling performance of profile control agent for fractured gas condensate reservoirs

针对裂缝型凝析气藏调剖剂封堵强度不够、调剖深度有限的难点,通过试验找出了一种新型、性能更加稳定的弱凝胶调剖剂,该调剖体系形成的弱凝胶稳定性好。在对其成胶性能的研究后认为聚合物浓度、交联剂浓度、温度、pH值和矿化度是影响该调剖体系成胶性能的主要因素:聚合物浓度增加,体系成胶时间缩短,强度增强;交联剂浓度增加,成胶时间缩短,强度增加;随着温度升高,成胶时间缩短,强度增加,当温度高到一定值时,弱凝胶强度变弱;该调剖剂在中性至弱碱性环境下利于成胶;聚合物分子具有盐敏性,但矿化度较低时,矿化度对交联体系成胶时间和强度的影响并不大。

In view of less blocking intensity and shallow profile depth of the existing profile control agent for fractured gas condensate reservoirs,a new type of slight gel profile control agent of higher stability was developed.Based on the researches of its gelling performance,concentration of polymer and cross linking agent,temperature,pH value and salinity were found to be the main influential factors.With polymer concentration,concentration of cross linking agent increasing and temperature rising,the gelation time became shortened with the intensity incremented.But when the temperature reaches a particular value,the intensity of slight gelation became becomes weaker.It shows that for the new type of profile control agent,neutral to alkalescent solution is favour of its gelation and it has characteristic of salinity sensitivity.While,at low salinity it has little effect on the gelation time and the intensity of cross linked system.Based on the above analysis,it is proved that this study is of vital importance to the development of fractured gas condensate reservoirs.