摘要
初步形成适合长庆上古生界低渗、低压气藏的气井 (井深 40 0 0m以内 )CO2 泡沫压裂工艺技术。在压裂液体系的室内研究中 ,选用羟丙基胍胶作为交联的增稠剂 ,研究合成了AC 8酸性交联剂 ,使压裂液在酸性条件下有较高的黏度和携砂能力 ,优选出在清水中发泡性能较好的YFP 1发泡剂和CQ A1、DL 10助排剂。现场压裂施工通过增大CO2 用量来增加施工规模 ,通过提高基液浓度 ,通过添加表面活性剂以保证压裂液与液体CO2 完全混合并乳化 ,以及保持压裂液一定排量来保证实现较高砂比。现场试验 19井次 ,14井次增产效果明显。与常规水基压裂液相比 ,CO2 泡沫压裂液的返排率提高近5 0 %、返排时间缩短了近 40h、对地层的伤害率 (平均为 48.5 1% )降低了近 3 0 %。图 4表 5参
CO 2 foam hydraulic fracturing technology was applied to the low permeability and low pressure Upper Paleozoic gas reservoirs (depth within 4000m) in the Changqing Oilfield for production increase experiment. With HPG as thickening agent, AC 8 acidic cross linker was developed in the frac fluid research. YFP 1 foaming agent, CQ A1 and DL 10 cleaning additives were selected because of their excellent foaming characteristics in water. Intensive hydraulic fractures were produced by applying increased amount of liquefied CO 2 . Comparing with water based frac fluid, application of CO 2 foam frac fluid will typically increase flow back efficiency by 50%, shorten flow back time by 40 hours, and reduce formation damage by 30% (average formation damage is 48.51%).
出处
《石油勘探与开发》
SCIE
EI
CAS
CSCD
北大核心
2003年第4期111-113,共3页
Petroleum Exploration and Development
