【作者】 赵国庆；

【导师】 李英；

【作者基本信息】 山东大学 ， 物理化学， 2007， 硕士

【摘要】 本论文研究包括两部分内容：第一部分主要研究水基泡沫表观性能，建立了系统的泡沫表观性能的评价方法，并考察了其主要的影响因素；第二部分主要探讨了泡沫在高温下的稳定机制，并研究了高温地层自生泡沫组合物在稠油开采中的应用。泡沫是气体和液体混合而成的多孔膜状分散体系，因其独特的物理化学性质，在石油化学、日用化学、食品科学、矿物浮选等领域被广泛应用，引起众多学者的关注。本文在前人工作的基础上，建立了一系列对水基泡沫表观性能的评价方法，对泡沫生成方式、泡沫剂的起泡能力、泡沫稳定性、泡沫的携液和析液、泡沫粘度、泡沫尺寸分布等进行了研究，并考察了表面活性剂结构类型、表面活性剂浓度、表面活性剂复配、聚合物的加入等因素对泡沫表观性能的影响，探讨泡沫的表观性能、微观机制和实际应用三者之间的内在联系。泡沫的形成是一个能量升高的过程，因此表面张力越低，形成单泡所需要的能量越低，起泡能力越好，但是本文研究表明，起泡能力和表面张力往往不呈线形对应关系，引入能量的方式和大小对泡沫的形成有重要的影响，在引入能量相等的条件下，对比生成泡沫量的多少，以考察起泡能力才能够给出对实际应用有指导意义的结论。泡沫稳定性一直是水基泡沫研究的核心问题，也是影响其实际应用的关键问题，本文在低温时（＜100℃）采用泡沫衰减法；高温时（＞100℃）采用泡沫岩芯封堵法，考察了多种表面活性剂的泡沫稳定性，并探讨了表面活性剂结构类型、表面活性剂浓度、表面活性剂复配、聚合物的加入、温度等因素对泡沫稳定性的影响。低温下泡沫的衰减一般经历泡沫析液区、泡沫破灭区和泡沫亚稳定区。亚稳定区的泡沫在无外力干扰时能稳定存在，但此时泡沫膜很薄，稍有干扰就会迅速破裂，因此本文采用半衰期和衰减曲线相结合，综合考察泡沫的稳定性。泡沫的析液对泡沫稳定性非常重要，在没有外界干扰的情况下，快速的析液可能导致泡沫快速的破灭。本文采用电导法定量检测泡沫析液，该方法对泡沫液膜的变化敏感，能实时反应泡沫内液体含量的多少，简单而准确。而且该方法还可反映界面膜组成的变化，为从理论上探讨泡沫的稳定机理提供重要信息。本文采用电导法考察泡沫析液的实验结果表明，随着表面活性剂浓度的升高，泡沫的携液和持液能力都增强；聚合物的加入提高了溶液的粘度，延长了泡沫的析液时间，但是液相粘度仅为辅助因素，若没有足够的表面活性剂形成稳定的界面膜，聚合物增强泡沫稳定性的功能就不能充分发挥，因此严格控制聚合物和表面活性剂的比例，才能保证聚合物增强泡沫的效果。水基泡沫的应用范围非常广泛，有些重要应用涉及高温下泡沫的形成和稳定性，但目前对泡沫稳定性的研究报道基本集中在常规温度下的泡沫，泡沫在极高温条件下的稳定机理非常缺乏，严重制约了泡沫在高温条件下的应用，如在稠油热采中提高采收率。本文分别用泡沫衰减法和泡沫岩芯封堵法测定在不同温度下的泡沫稳定性，并采用动态表面张力、界面流变、分子模拟等手段分析泡沫稳定机理。实验表明，引起泡沫的衰变的原因主要是泡沫中液体的流失和气体透过液膜扩散。低温时，气体的扩散和水的蒸发都较慢，相对来说，对泡沫稳定性影响更大的是排液过程；随着温度的升高，水分的蒸发和气体的扩散急剧加快，此时界面膜的结构和强度起决定作用。本文的研究发现超长疏水链（碳数＞20）型的离子型表面活性剂，在高温下头基的“锚定作用”减弱，其疏水链无法在气／水界面直立或分立地存在，疏水链相互交叉缠绕，增加了界面膜的强度，减缓了气体通过液膜的扩散，形成的泡沫在高温下有较好的稳定性，即表面活性剂的疏水链构象及相互作用对高温下泡沫的稳定性有重要影响，并提出了新的高温泡沫稳定机理。另外，本文还研究了高温地层自生泡沫在稠油开发中的应用，提出一种新的高温地层自生泡沫方法。选用能产生N₂或CO₂气体的反应，考察了反应的起始温度、反应物的浓度等对产气条件的影响，得到适用的产气体系，并选择一种耐高温并具有高油／水界面活性和高泡沫稳定性的表面活性剂做为起泡剂，形成高温地层自生泡沫组合物。高温蒸汽驱油实验表明，初期注入组合物，然后注入蒸汽引发反应，在岩芯中自发产生稳定的泡沫，泡沫封堵防止汽窜，提高高温蒸汽的波及系数，并提高吸油效率和促使原油有效分散，从而大幅度提高稠油采收率，是一种很有潜力的稠油开采方法。本论文的主要创新点：1．建立了一系列水基泡沫表观性能的评价方法，对泡沫生成方式、起泡能力、泡沫稳定性、泡沫的携液和析液、泡沫粘度、泡沫尺寸分布等开展了较系统的研究，考察了表面活性剂的结构类型、表面活性剂浓度、表面活性剂复配、聚合物的加入等因素对泡沫表观性能的影响。2．本文分别用泡沫衰减法和泡沫岩芯封堵法测定不同温度下的泡沫稳定性，并采用动态表面张力、界面流变、分子模拟等手段分析泡沫的稳定机理，提出了水基泡沫在高温下稳定的新机制。3．提出一种高温地层自生泡沫方法，并开发了高温地层自生泡沫复合物用于稠油开采提高采收率。经高温蒸汽驱油实验表明，初期注入高温地层自生泡沫组合物，然后注入蒸汽引发反应，在岩芯中自发产生稳定的泡沫，泡沫封堵防止汽窜，提高高温蒸汽的波及系数，促使原油有效分散，从而大幅度提高稠油采收率，是一种很有潜力的稠油开采方法。更多还原

【Abstract】 There were two sections in this paper. One was about the evaluation of foam apparent properties and their influencing factors. The other was about the foam stability mechanism study under high temperature and the stratum authigenic foam used in heavy oil recovery.Foam was an especial colloidal disperse system engendered by the dispersing of indiscerptible or tinily dissolved gas into liquid solution, which was used widely in petrochemistry, cosmetics, detergent chemistry, mineral floatation, food and so on because of its special properties.A series of foam properties evaluation methods were developed in this paper based on the former work, and systematic research work about foam generation way, foamability, foam stability, the ability to take and keep liquid, foam viscosity and foam size distribution had been done. And the effect of factors surfactant structure, surfactant concentration, surfactant synergism and polymer on the foam apparent properties were also studied, in order to find the relationship among foam apparent properties, micro mechanism and foam application.The formation of bubble was an energy increasing process, the energy needed to form a bubble increased with surface tension, so the lower surface tension it has, the better foamability it was. It was found in the paper that the foamability didn’t have a linear relationship with the surface tension because of the introduction of gas and energy affected by bulk solution and foam, and it suggested that foamability should be evaluated at the situations that the foam was generated with the same energy.Foam stability was crucial for foam study and its application. The foam stability at temperature below 100℃ and above 100℃ was investigated by foam colume decay method and foam block in sand-pack pipe method.It was unsuitable to reflect the foam stability by half-life bucause of the sub-stable foam which was very sensitive to disturbance and useless for application. In the paper the foam stability was evaluated by half-life and foam decay curve together.Foam drainage was also very important for foam stability. Fast drainage resulted in fast foam break-up under no disturbance. In the paper electric conductivity method was used to measure foam drainge process, which was simple and accurate, and was very sensitive to the interfacial changes. The experimental results showed that, the ability for foam to take and keep liquid increased with surfactant concentration, and the foam drainage process was staved by adding polymer, but the polymer could not strengthen foam stability only if the surfactant could form stable interfacial films.Most reports on foam stability were under low temperature（<100℃）, and the foam stability mechanism under high temperature was still unclear, while which is important for foam used at ultra-high temperature. Foam stability of surfactants with different hydrophobic chain length, was investigated by gas flow method and foam-block in sand-pack pipe method at different temperature. The experimental results showed that the foam stability increased with the chain length. Dynamic surface tension, interfacial rheometer and molecular simulation were used to study the stable mechanism of foam under high temperature in the paper, and a new foam stable mechanism was found out.The foam decay was dominated by foam drainage and gas dispersion through the foam film, and the foam decay was controlled by foam drainge when the temperature was low, because the foam drainage and gas dispersion rate was slowly. When temperature increased, the evaporation and gas dispersion increased and the foam stability was dominated by the film structure and strength. When the carbon number of the hydrophobic chain of surfactant was larger than 20, the hydration of the head group of surfactant could not support the chain to keep vertical and unattached, and the hydrophobic chain cross-link with each other, which result the viscoelastic modulus of the film increase sharply, then the foam film was strengthened, and the gas dispersion was decreased, so that the foam could be stable under high temperature.Besides, a new type of stratum authigenic foam mixture which could be used in heavy oil recovery was studied in the paper. A typical reaction which could released N² and CO₂ was chosen, and its reactive conditions including reactant concentration, reactive temperature and deflation rate were studied. The authigenic foam mixture still included a surfactant which could make the foam stable under high temperature, and had high oil/water interface activity. The oil recovery experiment results showed that, the reaction started and released gas after the authigenic foam mixture was injected into the sand-pack pipe with steam, and foam was generated in the sand-pack pipe and improve both vertical and horizontal sweep efficiency of the hot steam by plugging high permeability zones and the oil recovery was improved. The innovations in the thesis are as follows:1. A series of foam properties evaluation method were developed in this paper, systematic research work about foam generation way, foamability, foam stability, the ability to take and keep liquid, foam viscosity and foam size distribution had been done. And the effect of factors surfactant structure, surfactant concentration, surfactant synergism and polymer on the foam apparent properties were also studied.2. Foam stability of surfactants with different hydrophobic chain length at different temperature was investigated by foam decay method and foam-block in sand-pack pipe method. Dynamic surface tension, interfacial rheometer and molecular simulation were used to study the stable mechanism, and a new foam stable mechanism under high temperature was put forward.3. A new type of stratum authigenic foam mixture which could be used in heavy oil recovery was studied. The oil recovery room experiment results showed that, the reaction started in the sand-pack and gas was released after the authigenic foam mixture was injected into the sand-pack pipe with steam, by which foam was generated, both vertical and horizontal sweep efficiency of the steam were improved because high permeability zones were pluged by foam, and then the oil recovery was enhanced.更多还原