自产气泡沫酸酸化技术

Acid Treating Technology in Self-productive Gas Foamed Acid

针对低渗透油田重复酸化油井由于地层的非均质性和能量不足,造成酸液在地层中指进严重、返排速度慢、酸化效果差等现象,提出了自产气泡沫酸酸化技术。通过研制的自产气剂和DXQ-1高温起泡助排剂,实现自产气泡沫酸化。室内评价得出,自产气剂在酸液中或温度高于57℃时即可产生CO2气体,发气量大。DXQ-1高温起泡助排剂初期起泡速度快,稳泡能力强,具有较高的表面活性和耐温性。自产气剂在井下生成泡沫,利用泡沫产生的贾敏效应,封堵地层中的大孔道,使后续酸液转向,提高了酸液与地层的作用效率;产生的气体和起泡剂具有高表面活性,大大提高了返排效果。在新民采油厂油井用该体系酸化,注入压力明显提高,返排速度快,增油效果好,施工工艺简单。

Inhomageneity and energy scarcity of the formation in Oil-well treated repeatedly with acid in low permeability oil-field lead to serious fingering and poor backflow of acid liquid, resulting in poor acidizing impact. In order to solve the problem, self-pro- ductive gas agent and hot foaming cleanup additive called DXQ-1 are used for Foamed Acid by Self-productive Gas. Laboratory study indicates that self-productive gas agent can produce abundant carbon dioxide in the presence of acids or at high temperature （ 〉57 ℃ ） . DXQ-1 with high surface activity and strong ability of anti- temperature can make acid liquid into foam quickly at the first period and enhance the stabilization of foam. The foam produced in formation can block big porous channel so that it change flowing diversion of following acid liquid because of ＂Jiamin action＂ and increase injection pressure, which increases the reaction efficiency between acid and formation. The gas and the foaming agent with high surface activity can decrease crude viscosity and is favorable to flowing back. It was found that the system had some characters as follows： improving injection pressure apparently; high flowing back speed; increasing oil production obviously; simple construction process, when it was applied in oil well of Xinmin oil production plant.