共查询到18条相似文献,搜索用时 296 毫秒
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聚合物驱作为一种成熟的提高采收率的方法,得到了工业化的推广应用并且取得了显著效果。为了更加经济有效的使用聚合物驱油,需要对聚合物溶液在微观孔道中的渗流机理、流动特征进行详细的研究。本文将油藏孔隙简化为突缩孔道,应用有限体积方法对黏弹性聚合物溶液在微观孔道中的流动进行模拟,得到了较高威森博格数(We)下的数值解。利用数值分析得到的数值解绘制速度等值线图、流函数等值线图、压力等值线图以及相关曲线,分析研究粘弹性聚合物溶液在微观孔道中的渗流特征。研究表明,聚合物溶液的黏弹性是影响波及效率的主要因素,随着威森博格数(We)的增加,孔道直径突变形成的凸角处流体的速度逐渐增加,波及的范围逐渐增大,有利于凸角处的残余油变成可动油,从而提高聚合物溶液的微观波及效率。 相似文献
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以聚丙烯酰胺(HPAM)和梳形聚合物(KYPAM)两类具有代表性的聚合物为研究对象,对其驱油过程进行了室内实验模拟,分析不同相对分子质量HPAM和KYPAM的黏弹性、毛管数对原油驱采效率及残余油饱和度的影响规律,对比分析不同质量浓度条件下HPAM和KYPAM溶液在驱采过程中其自身黏度、幂律指数及黏弹性等参数的变化规律,结合实验结果剖析驱采过程中不同流体的微观作用机理.结果表明:驱油效率与毛管数成正相关,前者随后者的增加而增加;可以通过适当增加毛管数,或者提高聚合物溶液弹性以提高驱油效率;梳形聚合物具有较高的黏度和较低的弹性,在毛管数一致的情况下,其驱油效率的数值较低;驱油效率受聚合物溶液的弹性微观力主导,与黏度无关. 相似文献
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电渗析处理后油田污水在聚合物驱和复合驱中的应用 总被引:1,自引:0,他引:1
利用电渗析法处理油田污水,研究了处理前后3种水所配制的聚合物溶液的流变性;淡水所配制的聚合物溶液黏度最高;指出矿化度和阳离子是造成3种水聚合物溶液流变性不同的根本原因,淡水可以作为聚合物驱的配注水。通过3种水在不同质量分数碱(0.4%、0.6%、0.8%、1.0%、1.2%)的三元复合体系的界面张力曲线,得出浓水三元复合体系达到超低界面张力时碱的质量分数范围最宽(0.4%~1.1%)。根据现场三元复合体系配方(聚合物质量浓度为1350mg/L,ORS-41的质量分数为0.3%,碱的质量分数为1%)选择了浓水三元复合体系碱的质量分数为0.6%时,两个三元复合体系黏度相近。对两个三元复合体系配方在光刻模型上进行了微观驱油实验,结果表明:浓水低碱三元复合体系也能驱替各种残余油,具有良好的驱油效果。 相似文献
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《应用化工》2022,(Z1):194-197
聚合物驱过程中由于三相渗流现象,相对渗透率曲线的确定有很大的难度。基于渤海油田物理模型,进行数值模拟研究,确定聚合物驱不同阶段的相对渗透率曲线,并对比分析异同点。结果表明:①吸附滞留的聚合物分子对岩心的水相渗透率选择性降低,但对油相渗透率影响较小,为选择性调剖堵水提供理论依据。不同阶段水相渗透率曲线为聚合物驱过程中含水率的变化提供了理论依据;②水相渗透率的降低程度和地层中聚合物的含量相关,直接聚驱、水驱后聚驱的水相渗透率曲线差别相对较小;③直接聚驱、水驱后聚驱、后续水驱阶段均能很好的降低水相渗透率,但水驱后聚驱的残余油饱和度最低,说明事先注入一定量的水,能更好地发挥聚合物提高波及体积和驱油效率的作用,采出更多的残余油。以上研究为矿场聚合物驱数值模拟提供参数,指导聚合物驱矿场试验。 相似文献
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聚合物驱油技术是油田进入开发后期的一种重要的三次采油技术,该技术用聚合物水溶液为驱油剂,以增加注入水的粘度,提高其波及效率,从而达到提高原油采收率的目的。配制的聚合物溶液的粘度越高,其波及面积越大,驱油效果也就越理想。因此聚合物驱油的关键是保持聚合物溶液的粘弹性,因此,我们在实施聚合物驱油之前,首先要搞清影响聚合物溶液粘度的主要因素,以便在设计聚合物溶液配制体系时,最大限度提高聚合物溶液的粘度,从而提高聚合物溶液粘度的保留率,确保聚合物驱的效果。本文即针对影响聚合物溶液粘度的主要因素展开了研究和探讨,并提出应对措施。 相似文献
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Jamal Aalaie Khosrow Jarrahian Saeed Ghorashi Vali Ahmad Sajjadian 《Iranian Polymer Journal》2014,23(11):827-834
Four polymeric solutions based on xanthan, high and low molecular weight sulfonated polyacrylamides, and hydrolyzed polyacrylamide were prepared in aqueous solutions and their behaviors in enhanced oil recovery applications were investigated. The effect of thermal aging on polymer solutions was evaluated through rheological measurement. Pendant drop method was also used for measuring the interfacial tension (IFT) between crude oil and brine containing different polymer solutions. Moreover, the zeta potential of the oil reservoir particles treated with oil and polymer was determined by electrophoresis method in a nano-zeta meter instrument. In addition, sand pack and core flooding setup were used for evaluating the effectiveness of the polymer solutions in porous media. Polymer solutions displayed non-Newtonian behavior in almost the whole range of the shear rate applied; a shear thinning behavior was seen. Furthermore, the aging of polymers in formation water decreased the shear viscosity of all the polymers. The oil/water IFT decreased by the addition of polymers to water. The effect of xanthan polymer on zeta potential value was greater than that of the three acrylamide-based polymers. According to sand pack tests, by increasing the polymer concentration, the incremental oil recovery initially increased up to a polymer concentration of 3,500 ppm and then started to fall. Recovery factor increased from 50 to 65 % using the polymer solution in core flooding experiments. By increasing the injection rate from 0.2 to 3 mL/min, the injected fluid had less time to sweep the pores and consequently the amount of recovered oil decreased. 相似文献
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不同分子量聚合物驱相对渗透率曲线对比研究 总被引:3,自引:0,他引:3
聚合物驱相对渗透率曲线是描述多孔介质中多相渗流动态及油田聚驱开发指标计算和预测的重要基础资料,而增大聚合物的相对分子量是提高采出程度的重要措施之一。本文选取五种不同分子量的聚合物,通过大量岩心实验,利用非稳态法测定了不同分子量分别在相同浓度和相同粘度条件下的聚合物驱相对渗透率曲线。结果表明,随着聚合物分子量的增加,在相同含水饱和度下聚合物相的相对渗透率逐渐降低;油水两相跨度逐渐增大;曲线的右端点和等渗点都随着分子量的增大向右偏移,说明增加聚合物溶液的粘弹性确实可以提高岩心内部的微观驱油效率。文中还首次给出了聚合物驱残余油饱和度与聚合物分子量之间的数学关系式,为不同分子量聚合物驱数值模拟研究过程中数学模型的完善提供了理论基础。 相似文献
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A water‐soluble micro‐crosslinked associating polymer (PASA‐PL): poly (acrylamide/butyl styrene/sodium 2‐acrylamido‐2‐methylpropane sulphonate) (PASA)–phenolic aldehyde (PL) was prepared to reduce the critical associated concentration and enhance the thickening properties for the linear PASA polymer in aqueous and brine solutions. The consecutive steady shear and viscoelastic properties were investigated to explore the correlations between the rheologic performance and supramolecular structures for the PASA‐PL brine solutions. Upon consecutive steady shear, the intermolecular hydrophobic association is greatly reinforced because of the expansion of the coiled PASA‐PL chains at the suitable shear rate, and the brine solution exhibits obvious shear thickening behavior. The steady shear results show that the intermolecular hydrophobic association is reversible, and that the polymer chains do not degrade upon shearing. The PASA‐PL brine solutions with 50 g L−1 NaCl have predominantly elastic character over the angular frequency range at the polymer concentration higher than 1.0 g L−1, which is remarkably strengthened with a slight increase in polymer concentration. The PASA‐PL brine solutions display a salt‐thickening effect and predominantly exhibit elastic character over the angular frequency range at 10–50 g L−1 NaCl. These results demonstrate that the viscoelastic behavior of the PASA‐PL solutions mainly depends on the formation of hydrophobically associated structures via the intermolecular association strengthened by the micro‐crosslink of PASA with PL. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
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《Journal of Industrial and Engineering Chemistry》2014,20(2):656-667
Polymer flooding has been widely used in petroleum industry. With the development of theory and technology, some problems in the existing models of polymer flooding appear during simulation. Based on the characteristics of polymer and offshore oilfield such as viscoelasticity, degradation effect and strong salt-sensitive effect, a novel model of viscoelastic polymer flooding is built, and the validation is verified. After comparing the distributions of effective viscosity and residual oil of taking account of elasticity and taking no account of elasticity, it is used to investigate the effects of injection rate, polymer molecular weight, salinity, degradation rate and well space. 相似文献
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与常规聚驱采出水相比,高含聚采出水中聚合物浓度较高,粘度较大,Zeta电位电负值较高,小油珠所占比例较大,乳化程度较高,使得高含聚采出水油水分离难度远远高于常规聚驱采出水。高含聚采出水经过24h静沉,水中残余含油量能达到过滤单元进水要求;高含聚采出水中悬浮固体随着沉降时间的延长呈现忽高忽低的交替变化,仅仅通过单一沉降方式,其去除率不高;通过引入气浮的方式,能大大缩短油水分离时间,有效提高高含聚采出水油水分离效率;离心分离技术能在很短的时间内实现油、水、固三相的有效分离,并达到聚驱高渗透回注水指标要求。 相似文献