阿姆河地区碳酸盐岩裂缝性地层堵漏技术研究

发布时间：2018-05-04 06:38

本文选题：阿姆河地区 + 裂缝　；参考：《西南石油大学》2015年硕士论文

【摘要】：士库曼斯坦是世界第五大天然气资源国,天然气储量十分丰富,总资源量达到24.6×1012m3。阿姆河地区是土库曼斯坦最大的产气区域,该地区碳酸盐岩地层裂缝发育,为油气提供了良好的储集空间和渗流通道,但也导致了钻井过程中井漏事故频发,且大裂缝恶性漏失常常引起又喷又漏的复杂事故。现有堵漏技术处理恶性漏失成功率低,对储层伤害大,治理周期长,且堵漏材料损失巨大,严重影响了该地区勘探开发进度和经济效益,储层井漏问题已成为制约该地区安全钻井的技术瓶颈。因此,开发出适用于阿姆河地区碳酸盐岩裂缝性储层的堵漏技术十分必要。本文在对阿姆河地区取芯资料、地质资料和钻完井资料进行统计分析的基础上,围绕阿姆河地区碳酸盐岩裂缝性地层堵漏技术建立,从堵漏材料优选和承压封堵能力评价等方面开展了系统的实验研究,主要取得了以下成果和认识： (1)该地区井漏主要集中在卡洛夫～牛津阶碳酸盐岩储层,井漏问题的重点和难点是“漏储同层”,其根本原因是地层承压能力低,钻井安全密度窗口窄。基于此认识,提出了解决该地区井漏问题的技术途径：以现有的堵漏机理为基础,优选出适用于碳酸盐岩储层的高性能堵漏材料,配合一定的施工工艺,通过堵漏材料之间相互协同增效,形成高强度致密段塞,稳定封堵裂缝,从而提高地层承压能力。 (2)以堵漏机理为指导,结合“漏储同层”和提高承压能力对堵漏材料的要求,优选出了适用于阿姆河地区的三种类型的堵漏材料——桥塞材料(方解石颗粒材料、雷特片状材料和雷特纤维材料)、延迟膨胀剂GWS-1和HHH堵漏材料。 (3)以漏失量和承压能力为考察指标,在大量承压堵漏实验的基础上,优选得到了封堵效果较好的堵漏配方。最优堵漏配方为：基浆+5%方解石颗粒+2%雷特片状材料+1%雷特纤维+6%GWS-1+60%HHH+0.2%焦磷酸钠+0.1%NaOH+0.5%纤维+3%石英砂+重晶石,其中基浆配方为：6%膨润土浆+0.3%PAC-HV。该配方在4MPa下封堵3mm裂缝累计漏失量不超过10%。实验证明,该配方对裂缝适应能力强,承压能力高,应用范围广,且可以酸化解堵,但施工时堵漏浆需分先后泵入地层,应全面考虑,精细施工。 (4)该堵漏配方在土库曼斯坦B井的现场试验应用表明,该配方对阿姆河地区碳酸盐岩裂缝储层的严重井漏问题具有较好的封堵效果,但堵漏浆初期流动性偏弱,泵送压力较大,仍需开展进一步研究。
[Abstract]:Skumanstein is the fifth largest natural gas resource country in the world, and its natural gas reserves are very rich, with a total resource of 24.6 脳 1012m3. The Amu River region is the largest gas-producing region in Turkmenistan. The fractures in carbonate strata in this area provide a good reservoir space and seepage passage for oil and gas, but also lead to frequent well leakage accidents during drilling. And the malignant leakage of the big crack often causes the complicated accident of spitting and leaking. The existing plugging techniques have low success rate in treating malignant leakage, great damage to reservoir, long treatment period, and huge loss of plugging materials, which seriously affect the progress of exploration and development and economic benefits in this area. The problem of reservoir well leakage has become a technical bottleneck restricting the safety of drilling in this area. Therefore, it is necessary to develop a plugging technique suitable for fractured carbonate reservoirs in Amu River area. Based on the statistical analysis of the core data, geological data and well drilling and completion data in the Amu River area, this paper establishes the plugging technology for fractured carbonate formation in the Amu River area. A systematic experimental study has been carried out from the aspects of optimal selection of plugging materials and evaluation of plugging capacity under pressure. The following results and understandings have been obtained: In this area, well leakage is mainly concentrated in Karov-Oxford carbonate reservoir. The key and difficult point of well leakage problem is "leaking reservoir with same layer", which is caused by low bearing capacity of formation and narrow window of drilling safety density. Based on this understanding, the technical approach to solve the well leakage problem in this area is put forward: based on the existing plugging mechanism, the high performance plugging material suitable for carbonate reservoir is selected, which is combined with certain construction technology. Through the synergistic and synergistic effect among the plugging materials, a high strength and dense slug is formed to stabilize the sealing of the fractures, thus improving the bearing capacity of the formation. (2) guided by the plugging mechanism, combined with the requirements of "the same layer of leakage storage" and the improvement of pressure bearing capacity, three types of plugging materials (calcite granular materials), which are suitable for the Amu River area, have been selected. Latte sheet and Rete fiber materials, delayed expansion agents GWS-1 and HHH plugging materials. (3) on the basis of a large number of experiments on pressure plugging, a better plugging formula was obtained by taking leakage loss and pressure capacity as the index of investigation. The optimum formula for blocking leakage is as follows: the base pulp is 5% calcite particle 2% latte material 1% Rete fiber 6%GWS-1 60%HHH 0.2% sodium pyrophosphate 0.5% fiber 3% quartz sand barite and the base pulp formula is 0. 3% bentonite slurry 0.3% PAC-HV. The optimum formula is as follows: 1% Rete fiber 6%GWS-1 60%HHH 0. 2% sodium pyrophosphate 0. 5% fiber 3% quartz sand barite. The cumulative leakage of 3mm cracks is not more than 10% under 4MPa. It is proved by experiments that the formula has strong adaptability to cracks, high bearing capacity, wide application range, and can dissolve plugging by acid. However, plugging slurry should be pumped into the formation successively during construction, which should be considered comprehensively and meticulously constructed. 4) the field test of this formula in well B of Turkmenistan shows that the formula has good plugging effect on the serious well leakage problem of carbonate fractured reservoir in Amr River area, but the initial fluidity of plugging slurry is weak, and the pumping pressure is high. Further research is still needed.
【学位授予单位】：西南石油大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TE28

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