含油泡沫改善井筒稠油流动性实验研究

发布时间：2018-04-04 00:36

本文选题：井筒稠油　切入点：含油泡沫　出处：《西南石油大学》2015年硕士论文

【摘要】：降低稠油粘度并改善稠油流动性的方法很多,其中通过形成含油泡沫从而改善稠油流动性是一种新颖的方法。在稀油紧缺,掺稀降黏经济性降低的时候,它为改善稠油井筒流动性提供了一种经济有效的补充。由于含油泡沫是气液两相流体,并且井筒中环境复杂多变,影响井筒中含油泡沫流变特征的因素很多。论文针对塔河油田7区稠油特点及现场实际情况,开展了以下几方面研究。 1.针对目标区块高矿化度地层水,优选了S156复配起泡体系。泡沫评价实验结果表明S156体系在23×104mg/L矿化度条件下具有良好适应性,在浓度0.2%时,FCI值最高达到3755.9mL.min。 2.研究了常温常压条件下影响含油泡沫性能的因素,对比总结出最有利于含油泡沫生成和稳定的条件。研究结果表明：在稠油黏度18620mPa·s,油水比1：2,S156浓度0.7%,较长的搅拌时间,适当的搅拌速率和较低温度条件下,更有利于获得稳定含油泡沫。在常温常压实验基础上,模拟井筒温度和压力条件,将气体融入液相配制活油。通过观察压力降低后的起泡情况,得出了有利于含油泡沫生成稳定的条件。在井筒压力足够高的情况下,加药点处的压力以高于20MPa为宜,氮气比空气和二氧化碳更适用,压降速度越大越有利于泡沫油形成。 3.通过物模实验模拟井筒中稠油流动状态,研究了含油泡沫在不同井筒深度的表观黏度分布,以及各深度下含油泡沫相对于井筒原始流体的降黏效率,并对管线出口端流体形态加以比对。实验结果显示,随井筒深度变浅,含油泡沫的表观黏度因温度降低逐渐增大,在1064m、1596m和2128m处的降黏效率分别为57.98%、79.48%和87.10%。出口流体对比结果表明,加入起泡剂和氮气后形成的含油泡沫和原始流体形态差异明显,油相、气相和水相能够在管线中充分混合形成含油泡沫,实现提高稠油流动性的目的。论文研究成果对塔河油田7区稠油开采有积极意义,并为类似稠油油田开展含油泡沫改善井筒稠油流动性的研究提供了有益参考与借鉴。
[Abstract]:There are many ways to reduce viscous oil viscosity and improve heavy oil fluidity.When the dilute oil is in short supply and the economy of reducing viscosity is reduced, it provides an economic and effective supplement for improving the wellbore fluidity of heavy oil.Because the oil-bearing foam is a gas-liquid two-phase fluid, and the environment in the wellbore is complex and changeable, there are many factors affecting the rheological characteristics of oil-bearing foam in the wellbore.According to the characteristics of heavy oil and the actual situation in Tahe Oilfield area 7, the following aspects have been studied in this paper.1.For high salinity formation water of target block, S 156 foaming system is selected.The results of foam evaluation show that S156 system has good adaptability under the condition of 23 脳 104mg/L mineralization, and the highest value of FCI is 3755.9 mL 路min when the concentration is 0.2.2.The factors affecting the properties of oil-bearing foam under normal temperature and atmospheric pressure were studied and the conditions most favorable to the formation and stability of oil-bearing foam were compared and summarized.The results show that when the viscosity of heavy oil is 18620mPa s, the ratio of oil to water is 1: 2, the concentration of S156 is 0.7, the stirring time is longer, the appropriate stirring rate and the condition of lower temperature are more favorable to obtain stable oil-bearing foam.On the basis of the experiment at room temperature and atmospheric pressure, the conditions of wellbore temperature and pressure are simulated, and the gas is mixed into liquid phase to prepare live oil.By observing the foaming condition after the pressure is reduced, the conditions conducive to the formation and stability of the oil-bearing foam are obtained.When the wellbore pressure is high enough, the pressure at the dosing point is higher than that of 20MPa, nitrogen is more suitable than air and carbon dioxide, and the higher the pressure drop is, the more favorable the foam oil is.3.The distribution of apparent viscosity of oil-bearing foam at different wellbore depths and the viscosity reduction efficiency of oil-containing foam compared with the original fluid in wellbore were studied by simulating the flow state of heavy oil in wellbore by physical model experiment.The fluid morphology at the outlet of the pipeline is compared.The experimental results show that the apparent viscosity of the oil-bearing foam increases gradually due to the decrease of temperature with the wellbore depth becoming shallower, and the viscosity reduction efficiency at 1064 m / 1596m and 2128m is 57.98% and 87.10%, respectively.The results of export fluid comparison show that the oil-bearing foam formed by adding foaming agent and nitrogen is obviously different from the original fluid. The oil phase, gas phase and water phase can be mixed in the pipeline to form the oil-bearing foam, and the purpose of enhancing the flow of heavy oil is achieved.The research results of this paper have positive significance for heavy oil recovery in area 7 of Tahe Oilfield, and provide useful reference and reference for similar heavy oil fields to carry out research on improving wellbore heavy oil fluidity with oil foam.
【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】：TE345

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