| 本文已被：浏览次 下载次 |
码上扫一扫！ |
|
|
| 低温油气藏胍胶压裂液破胶酶的研制与性能评价 |
|
达祺安1,2,姚传进1,2,3,曲晓欢1,2,褚程程1,2,马鑫1,2,雷光伦1,2,3
|
|
(1.非常规油气开发教育部重点实验室(中国石油大学(华东),山东青岛 266580;2. 中国石油大学(华东)石油工程学院, 山东青岛 266580;3.山东省油田化学重点实验室(中国石油大学(华东),山东青岛 266580)
|
|
| 摘要: |
| 针对低温油气藏胍胶压裂液破胶效率低,返排困难造成储层污染严重的问题,通过发酵学方法利用地衣芽孢杆菌GD-551研制出一种低温油气藏胍胶压裂液专用生物酶破胶剂；测试该生物酶破胶剂的储层适应性,对比不同条件下酶破胶剂与常规(NH4)2S2O8破胶剂的破胶性能；通过室内基质岩心与可视化裂缝模型实验对比酶破胶剂与(NH4)2S2O8对储层物性的伤害。结果表明:酶破胶剂适用的油气藏温度为30~60 ℃,pH值为5.5~8.0,总矿化度小于84 g/L；低温条件下酶破胶剂作用4 h后胍胶压裂液破胶率可超过95%且生成的残渣含量低于行业标准(600 mg/L),同条件下(NH4)2S2O8破胶率不足15%且生成的残渣含量较酶破胶剂高77%以上；与(NH4)2S2O8相比,使用酶破胶剂的基质与裂缝模型反向注入压力更低,渗透率与导流能力下降幅度更小,酶破胶剂对基质渗透率与裂缝支撑剂层导流能力造成的伤害远小于传统的(NH4)2S2O8破胶剂。 |
| 关键词: 低温油气藏 储层伤害 胍胶压裂液 酶破胶剂 可视化实验 |
| DOI：10.3969/j.issn.1673-5005.2022.02.014 |
| 分类号::TE 312 |
| 文献标识码:A |
| 基金项目:国家自然科学基金项目(51974341,51874330);山东省重点研发计划项目(2019GSF109095,2019RKE28001); 中央高校自主创新科研计划项目(20CX06070A,19CX05005A-6) |
|
| Preparation and performance evaluation of enzyme gel breaker for guar-based fracturing fluid in low-temperature reservoirs |
|
DA Qi 'an1,2, YAO Chuanjin1,2,3, QU Xiaohuan1,2, CHU Chengcheng1,2, MA Xin1,2, LEI Guanglun1,2,3
|
|
(1.Key Laboratory of Unconventional Oil & Gas Development (China University of Petroleum (East China)), Ministry of Education, Qingdao 266580, China;2.School of Petroleum Engineering in China University of Petroleum (East China), Qingdao 266580, China;3.Shandong Key Laboratory of Oilfield Chemistry(China University of Petroleum(East China)), Qingdao 266580, China)
|
| Abstract: |
| In applying guar gum fracturing fluid in low-temperature reservoirs,serious reservoir damage can occur due to low gel-breaking and flow-back efficiency of the fracturing fluid. In this study, a special enzyme breaker for guar gum fracturing fluid used in low-temperature reservoirs was developed,using Bacillus licheniformis GD-551 by a fermentation method. The reservoir adaptability of the enzyme gel breaker was tested, and its gel breaking performance was compared with a conventional breaker (NH4)2S2O8 under different conditions. The influences on reservoir damage of the two breakers were also investigated using laboratory matrix core via visual fracture model experiments. The results show that the enzyme breaker can be applied at temperature of 30-60 ℃, pH value of 5.5-8.0, and with salinity less than 84 g/L. Under low temperature conditions, the gel breaking efficiency of the enzyme breakercan reach to more than 95% after reaction with the guar gum fracturing fluid for 4 hours, and the residue content generated was lower than the industry standard of 600 mg/L. At the same conditions, the gel breaking efficiency of (NH4)2S2O8 was less than 15%, and its residue content was more than 77% higher than that of the enzyme breaker. After the reaction of the enzyme breaker with the fracturing fluid, the reverse injection pressure of the matrix and fracture became lower, and the reduction in permeability and conductivity was smaller. The damage caused by the enzyme to the matrix permeability and the conductivity of the fracture proppant layers was far less than that of (NH4)2S2O8. |
| Key words: low-temperature reservoir reservoir damage guar-based fracturing fluid enzyme breaker visualization experiment |
