CO2压裂技术在杏南试验区的应用研究CO2 fracturing technique applied in Xingnan test area
马健,张春龙
MA Jian1,2
摘要(Abstract)：
与常规压裂技术相比,CO2压裂技术具有低滤失、高返排、对油层伤害小、增产幅度大、有效期长等优点,该技术在利用CO2作为介质造缝的同时,还具备在地层温度下CO2快速气化、溶混于原油中、大幅度降低原油粘度和增加溶解气驱能量的独特增产机理。该文对该技术所适用的地质条件、压裂选井的原则及压裂施工的具体流程进行了阐述。杏南试验区3口井CO2压裂的现场应用效果表明,该技术不仅适用于厚油层和老井的重复压裂,而且对于表外储层和有效厚度小于0.5 m的薄差层也具有更好的增产效果。运用压裂有效期内最低增油模型,计算出该技术比普通压裂可多创效5.8~13.8万元,经济效益更为可观。CO2压裂技术是低压、低渗油层的一项较好的增产改造措施,它扩大了压裂选井选层的范围、提高了压裂效果,在杏南试验区具有广阔的应用前景。
Compared with conventional fracturing technique,CO2 fracturing technique has several advantages including low filtration,high flowback,small damage in reservoir,increasing production with a great degree and longer effective period.The technique has unique increasing-production mechanism when CO2 is acted as medium to develop fracture,which makes CO2 fast gasify,dissolve in crude oil,largely decline oil viscosity and increase capacity of solution gas drive.In addition,geologic condition,fracturing selected well principles and procedure for fracturing operation are described in this paper.Its application effects show that,this technique is not only adapted to thick oil layer and repeated fracturing for oil wells but also achieves better results for out-surface reservoir and thin and poor layers with the effective thickness of less than 0.5m.Lowest increasing oil model in effective period is used to calculate profits by using this technique,showing that more than RMB $5.8×104-13.8 ×104 are obtained.CO2 fracturing technique is a better increasing production and reworked measures in low pressure and low permeable reservoirs.It enlarges the area for fracturing selected wells and layers and improves fracturing effects and has wide future in Xingnan development area.
关键词(KeyWords)：
CO2压裂;机理;地质条件;应用效果;经济效益
CO2 fracturing;mechanism;geologic condition;application effects;economic benefit
基金项目(Foundation):
作者(Author):
马健,张春龙
MA Jian1,2