Study on Technology for Protecting Loose Sandstone Reservoir in Bayan Oilfield
-
摘要: 巴彦油田储层属于中孔、中低渗为主的深部弱胶结砂岩储层,储层水敏性强,在用钻井液为淡水体系,抑制能力差,易引起地层水矿化度变化,导致储层污染。中国具有同样埋藏深度同时又具有类似储层物性特点的油田很少,需要针对疏松砂岩储层特点研发一种新型微米储层保护剂。在分析巴彦油田储层伤害因素的基础上,自主研发了一种兼具成膜与防膨效果的微米乳液储层保护剂,通过激光粒度分析、砂床封堵、PPA封堵滤失、扫描电镜等评价方法,验证了微米暂堵剂的广谱封堵和协同增效效果。该产品粒径D50≤2.17 μm,D90≤7.05 μm,线性膨胀降低率达到51.35%,与钻井液体系配伍性良好,与可酸溶材料配伍形成了一体化广谱封堵技术。室内实验表明,该广谱封堵技术针对弱胶结砂岩储层岩心渗透率恢复值可保持在90%以上。现场试验中,通过表皮系数测试和试油投产数据等综合对比表明,该广谱封堵技术具有良好的储层保护效果。Abstract: The reservoirs in the Bayan oilfield are weakly cemented sandstone reservoirs with medium and low permeability. Those reservoir formations are buried deep and are strongly water sensitive. Fresh water based drilling fluids have long been used to drill the wells, and because of the poor inhibitive capacity of the drilling fluids, the reservoirs are contaminated by the change in the salinity of the formation waters. Oilfields with the same buried depth and the similar reservoir physical properties in China are rarely seen, and a new micrometer sized reservoir protection additive is needed for drilling the loose sandstone reservoirs. Based on the analyses of the factors related to the reservoir damage in the Bayan oilfield, a micrometer sized emulsion reservoir protection agent with both filming and clay swelling inhibitive capacity was developed. The capacity of the reservoir protection agent to plug fractures with wide size distribution and the synergistic effect of the reservoir protection agent is verified using laser particle size analyzer, sand-bed plugging tester, PPA plugging filtration tester and SEM. The particle size of the reservoir protection agent D50 is ≤ 2.17 μm, and the D90 is ≤ 7.05 μm. The percent reduction of the linear swelling of cores tested with the reservoir protection agent is 51.35%. Compatibility of the reservoir protection agent with the drilling fluids in which it is used is satisfactory. The reservoir protection agent, combined with acid soluble materials, forms an integrated reservoir protection fluid capable of protecting reservoirs with various properties. Laboratory experimental results show that using this technology, percent permeability recovery of cores made with rock samples from weakly cemented reservoir sandstones can be 90% or higher. In field supplication, skin factor measurement and well production data all demonstrate the good reservoir protection capacity of this technology.
-
表 1 BH-NFT页岩膨胀实验
体系 页岩膨胀读数 页岩膨胀降低率/% 清水 15.65 7%氯化钾 13.22 15.10 清水+2%BH-NFT 7.61 51.35 表 2 聚合物钻井液的砂床封堵实验
序号 BH-NFT/% 砂床粒径/目 侵入深度/cm ① 0 20~40 30 ② 1 4.9 ③ 0 40~80 30 ④ 1 4.2 ⑤ 0 80~100 30 ⑥ 1 3.4 ⑦ 0 100~120 5.6 ⑧ 1 2.6 注:基浆为:聚合物钻井液+1%BH-HTF-1+1%BH-HTF-2,密度为1.28 g/cm3。 表 3 不同钻井液体系的PPA封堵能力评价实验
配方 不同时间(min)下的滤失量/mL 1 2.5 5 7.5 15 25 30 4%膨润土 5.8 10.0 15.0 22.0 36.0 44.0 52.0 聚合物钻井液 3.8 7.9 13.3 18.8 26.4 35.4 40.7 聚合物钻井液+1%BH-HTF-1 2.9 5.5 8.8 11.7 18.4 22.9 31.8 聚合物钻井液+1%BH-HTF-1+1%BH-HTF-2 1.4 2.2 5.5 6.9 8.2 10.7 12.8 聚合物钻井液+1%BH-HTF-1+1%BH-HTF-2+1%BH-NFT 0 2.4 3.9 5.4 5.9 6.2 6.6 表 4 在不同钻井液中加入复合封堵剂前后的性能
体系 复合封堵剂 PV/
mPa·sYP/
PaFL/
mLFLHTHP/
mL滚动回
收率/%聚合物
钻井液加入前 14 7 5.4 12.2 64.2 加入后 15 7 4.6 10.4 73.3 氯化钾
钻井液加入前 18 6 4.8 10.2 74.6 加入后 18 7 4.6 9.4 82.8 复合盐
钻井液加入前 20 11 4.8 9.8 78.4 加入后 21 10 4 8.6 86.2 注:复合封堵剂为:1%BH-HTF-1+1%BH-HTF-2+1%BH-NFT,FLHTHP在150 ℃、3.5 MPa下测定;滚动回收岩屑为兴华区块岩屑,清水滚动回收率为37.4%。 表 5 在不同钻井液中加入复合封堵剂前后的渗透率恢复值
钻井液 复合封堵剂 岩心号 K0/
mDKd/
mD渗透率
恢复值/%聚合物
钻井液加入前 027 143.7 81.48 56.7 加入后 032 133.56 130.09 97.4 氯化钾
钻井液加入前 4126 31.75 15.05 47.4 加入后 4135 33.67 31.41 93.3 复合盐
钻井液加入前 1688 59.79 35.46 59.3 加入后 1712 55.16 53.77 96.7 注:复合封堵剂为:1%BH-HTF-1+1%BH-HTF-2+1%BH-NFT;岩心污染评价实验条件为120 ℃、3.5 MPa、120 min。 表 6 实施油保前后钻井液性能对比
井号 井深/
m复合
封堵剂ρ/
g/cm3FLAPI/
mLFLHTHP/
mLPV/
mPa·sYP/
PaGel/
Pa/PaVs/
g·L-1MBT/
g·L-1兴华1-105 5012 加入前 1.25 4.8 11.2 22 9 3/8 14 64.35 5091 加入后 1.25 4.0 9.2 20 8 3/12 13 64.35 兴华12-1 5124 加入前 1.24 4.4 12.2 21 9 3/13 13 85.80 5315 加入后 1.24 3.7 9.6 23 13 4/17 15 92.95 注:复合封堵剂为:1%BH-HTF-1+1%BH-HTF-2+1%BH-NFT。 表 7 兴华区块储层保护实验数据对比
井号 试油层位 试油井段/m 产油量/(m3·d-1) 产油增幅/% 表皮系数 备注 兴华1-105 E3l2-2 5086.2~5091.6 34.29 -1.29 储保井 兴华1-111X E3l2-2 5211.0~5218.2 4.50 662 -0.35 对比井 兴华12-1 E3L2-3 5302.4~5315.0 64.80 -3.69 储保井 兴华12 E3L2-3 5238.6~5246.2 0.75 854 2.96 对比井 -
[1] 白小东,蒲晓林,张辉. 纳米成膜剂NM-1的合成及其在钻井液中的应用研究[J]. 钻井液与完井液,2007,24(1):13-14,36.BAI Xiaodong, PU Xiaolin, ZHANG Hui. Synthesis of Nano filming agent NM-1 and its application in drilling fluids[J]. Drilling Fluid & Completion Fluid, 2007, 24(1):13-14,36. [2] 邱正松,逄培成,黄维安,等. 页岩储层防水锁微乳液的制备与性能[J]. 石油学报,2013,34(2):334-339.QIU Zhengsong, PANG Peicheng, HUANG Weian, et al. Preparation and performance of anti-waterblock microemulsion for shale reservoirs[J]. Acta Petrolei Sinica, 2013, 34(2):334-339. [3] 耿学礼,苏延辉,郑晓斌,等. 纳米微球保护储层钻井液研究及应用[J]. 钻井液与完井液,2016,33(4):32-35.GENG Xueli, SU Yanhui, ZHENG Xiaobin, et al. Study and application of reservoir protection drilling fluid treated with Nano spheres[J]. Drilling Fluid & Completion Fluid, 2016, 33(4):32-35. [4] 蒋官澄,毛蕴才,周宝义,等. 暂堵型保护油气层钻井液技术研究进展与发展趋势[J]. 钻井液与完井液,2018,35(2):1-16.JIANG Guancheng, MAO Yuncai, ZHOU Baoyi, et al. Progress made and trend of development in studying on temporarily type plugging reservoir protection drilling fluids[J]. Drilling Fluid & Completion Fluid, 2018, 35(2):1-16. [5] 蒋官澄,程荣超,谭宾,等. 钻井过程中保护低渗特低渗油气层的必要性、 重要性与发展趋势[J]. 钻井液与完井液,2020,37(4):405-411.JIANG Guancheng, CHENG Rongchao, TAN Bin, et al. Protecting the low permeability and ultra-low permeability pay zones during drilling: necessity, importance and developing tendency[J]. Drilling Fluid & Completion Fluid, 2020, 37(4):405-411. [6] 蒋官澄,宣扬,王金树,等. 仿生固壁钻井液体系的研究与现场应用[J]. 钻井液与完井液,2014,31(3):1-5.JIANG Guancheng, XUAN Yang, WANG Jinshu, et al. Study and application of bionic borehole wall strengthening agent[J]. Drilling Fluid & Completion Fluid, 2014, 31(3):1-5. [7] 全晓虎,蒋官澄,吕传炳,等. 双疏型储层保护技术在吉兰泰油田的应用[J]. 钻井液与完井液,2020,37(3):306-312.QUAN Xiaohu, JIANG Guancheng, LV Chuanbing, et al. Reservoir protection with double hydrophobic agent in Jilantai oilfield[J]. Drilling Fluid & Completion Fluid, 2020, 37(3):306-312. [8] 郑淑杰,蒋官澄,肖成才,等. 纳米材料钻井液在大港油田的应用[J]. 钻井液与完井液,2017,34(5):14-19.ZHENG Shujie, JIANG Guancheng, XIAO Chengcai, et al. Application of a nanomaterial drilling fluid in Dagang oilfield[J]. Drilling Fluid & Completion Fluid, 2017, 34(5):14-19. [9] 李颖颖,蒋官澄,宣扬,等. 低孔低渗储层钻井液防水锁剂的研制与性能评价[J]. 钻井液与完井液,2014,31(2):9-12.LI Yingying, JIANG Guancheng, XUAN Yang, et al. Drillingfluid de-sign tO prevent form ation damage in high perm eability quartzarenitesandstones[J]. Drilling Fluid & Completion Fluid, 2014, 31(2):9-12. [10] 杨丽丽,武昀朋,蒋官澄,等. 自修复凝胶堵漏技术研究[J]. 钻井液与完井液,2023,40(1):47-53.YANG Lili, WU Yunpeng, JIANG Guancheng, et al. Lost circulation material and technology research of self-healing hydrogel[J]. Drilling Fluid & Completion Fluid, 2023, 40(1):47-53. [11] ABRAMS A. Mud design to minimize rock impairment due to particle invasion[J]. Journal of Petroleum Technology, 1977, 29(5):586-592. doi: 10.2118/5713-PA [12] 张金波,鄢捷年,赵海燕. 优选暂堵剂粒度分布的新方法[J]. 钻井液与完井液,2004,21(5):4-7.ZHANG Jinbo, YAN Jienian, ZHAO Haiyan. Optimization of bridging particle size distribution of drilling fluid for formation protection[J]. Drilling Fluid & Completion Fluid, 2004, 21(5):4-7. [13] SMITH P S, BROWNE S V, HEINZ T J, et al. Drilling fluid design to prevent formation damage in high permeability quartz arenite sandstones[C]//Paper presented at the SPE Annual Technical Conference and Exhibition, Denver, Colorado, October 1996: SPE36430-MS. -