【作者】 胡绍彬；

【导师】 刘永建；

【作者基本信息】 东北石油大学 ， 油气田开发工程， 2011， 博士

【摘要】 注蒸汽是提高稠油油藏采收率的有效方法。但在注蒸汽开采中,蒸汽“超覆”和“汽窜”导致注入的蒸汽大量损失和波及系数的降低,影响开采效果。不利的流度比是造成蒸汽超覆与汽窜的重要原因之一,改善流度比是提高蒸汽波及效率的有效途径。本文围绕改善注蒸汽热采流度比开展了以下研究：其一,开展了耐高温发泡剂研制与室内评价。首先,研制了阴离子型表面活性剂AGS-8和PMP-1。其次,开展了发泡剂室内静态和动态实验评价,将AGS-8和PMP-1与五种商业发泡剂F240B.SuntechⅣ、ATS、AOS2024和LD-Foam进行性能对比。结果表明：F240B、AGS-8、PMP-1在耐高温、发泡体积、半衰期、抗盐以及抗油等方面,综合性能最好；F240B、AGS-8及PMP-1发泡剂产生的阻力因子较大,且随温度的升高阻力因子下降幅度较小,表明这三种发泡剂具有良好的蒸汽流度控制能力；驱替0.5pv时,F240B、AGS-8和PMP-1的驱油效率分别达到65.3%、58.9%和51.6%。最后,开展了泡沫控制蒸汽流度的敏感因素研究。结果表明：当发泡剂溶液浓度较低时,阻力因子随发泡剂浓度增大迅速增大,当发泡剂溶液浓度超过0.5%以后,随发泡剂浓度的增加,阻力因子增大的趋势减缓；当含油饱和度超过15%时,随含油饱和度的继续增加,泡沫控制蒸汽流度的能力急剧降低；渗透率增大时阻力因子增大,渗透率高于8μm2后阻力因子基本不变；气液比在0.5～1.5的范围内泡沫具有较高的阻力因子,在现场施工中应尽量将气液比控制在0.5～1.5之间。其二,开展了蒸汽冷凝水流度控制化学剂筛选与评价。首先,根据蒸汽驱过程中在温度前缘前后温度发生大幅度变化的特性,提出采用具有特殊性质的化学剂来控制冷凝水相的流度。其原理是化学剂通过在地层中暂时和选择性地在水流通道中结晶,部分堵塞冷凝水流动通道降低冷凝水相的渗透率,从而控制其流度。其次,对化学剂控制水相流度进行了理论分析,论证了化学剂可以到达蒸汽前缘,分析了加入化学剂对蒸汽驱流度比、驱替效率的影响。再次,根据流度控制剂的性能要求,通过筛选,确定MCA可用于蒸汽驱中控制水相流度的化学剂。最后,开展了冷凝水流度控制室内模拟实验。结果表明,当MCA饱和度为1%pv时,岩心渗透率可减小到初值的20%左右；随着岩心中的MCA逐渐被溶解驱出,饱和度逐渐减小,岩心渗透率可恢复到初始渗透率的93%以上,表明由MCA结晶导致的岩心渗透率减小具有暂时性和可逆性。驱替2pv左右时,未添加MCA的驱油实验的平均驱油效率为53.24%,添加MCA的驱油实验的平均驱油效率为61.25%,使用MCA可使线性驱替实验的驱替效率平均增加原始地质储量的8%左右。其三,开展了稠油就地裂解催化体系研制与评价。首先,考察了辽河稠油水热裂解降粘与强化的可行性。结果表明：辽河稠油在240℃条件下经过24小时的水热裂解反应,粘度降低7.26%,其饱和烃、芳香烃含量增加,胶质和沥青质含量有所降低；反应体系中油砂的加入可使反应后的稠油降粘率增加了1倍左右；0.3%的硫酸亚铁与油砂共同作用可使稠油粘度降低55.02%,四氢化萘与矿物共同作用下,稠油降粘率可提高到40%左右,表明辽河稠油具有水热裂解反应性,催化剂与供氢剂能够强化辽河稠油水热裂解降粘。其次,以含镍和钴的矿物为原料制备了稠油就地裂解反应催化剂主剂,性能评价表明所研制的催化剂热稳定性良好、与地层水配伍、与油藏矿物具有协同性；筛选甲苯或混苯作为稠油催化裂解反应的供氢剂；选择石油磺酸盐作为助剂进一步提高稠油就地降粘效果。本文研制的稠油裂解降粘催化体系为：油酸钴/油酸镍催化剂加量0.2%、供氢剂甲苯加量1.0%、助剂石油磺酸盐加量0.3%。最后,稠油就地裂解催化体系室内评价结果表明,稠油在催化体系作用下进行水热裂解反应后,稠油品质得到提高,其饱和烃、芳香烃含量明显增大,胶质、沥青质含量明显降低,反应后稠油中C原子含量降低,H原子含量增加,硫元素含量明显下降,粘度不可逆地降低,降粘率可达90%左右,提高了稠油的流度。最后,进行了流度控制剂现场实施方案初步设计。关于流度控制剂的具体注入量、注入时机以及注入方式等需要根据油田实际情况进行后续计算、设计与完善。更多还原

【Abstract】 Thermal recovery by steam injection is an effective EOR method for heavy oil reservoir. But in the process of steam injection, "steam overlying" and "steam channeling" will cause adverse consequences of steam loss and sweep efficiency decrease, influencing the recovery effect. Unfavorable mobility ratio is one of the essential reasons causing steam overlying and channeling. It is an efficient way to promote the sweep efficiency of steam flooding through mobility ratio controlling. In order to improve the mobility ratio in steam injection process, the following work was carried out in this dissertation.Firstly, high-temperature foaming agents were prepared and evaluated in laboratory. First of all, anionic surfactant AGS-8 and PMP-1 were prepared. Next, the static and dynamic experimental evaluations were carried out to compare the properties of foaming agents AGS-8, PMP-1, F240B, SuntechⅣ, ATS, AOS2024 and LD-Foam. The results showed that in terms of temperature resistance, foam volume, foam half-life, salt tolerance, oil resistance, the agents of F240B, AGS-8 and PMP-1 have the best performance. F240B, AGS-8 and PMP-1 can generate large resistance factors, which decrease a little as temperature increasing, indicating that F240B, AGS-8 and PMP-1 can achieve good effect in steam mobility control. When flooded by 0.5pv, the displacement efficiencies of F240B, AGS-8 and PMP-1 are 65.3%,58.9% and 51.6% respectively. Finally, the sensitivity factors of steam mobility control by foam were studied. The results showed that for low concentration of foaming agent, the resistance factor of foam increased rapidly as the concentration increase, while for the foaming solution with concentration over 0.5%, the increasing tendency of resistance factor becomes weaker. The mobility control ability of foam decreased dramatically as the oil saturation increases to above 15%. The resistant factor increased as the increase of permeability, and after the permeability was higher than 8μm2, the resistant factor remained basically unchanged. The resistant factor was high as the gas-liquid ratio is in the range of 0.5～1.5.Secondly, chemical agent for controlling the mobility of steam condensation water was selected and evaluated. At First, in view of the characteristic of temperature change at the temperature front during the process of steam injection, the method to control mobility of water phase by chemical agent with special properties was put forward. The principle is to decrease the permeability of the condensation water through partially blocking the water flow channel by the temporary and selective crystallization of special chemical agent. Next, the mechnism of water phase mobility control by chemical agent was analyzed theoretically, the possibility of chemical agent to reach the steam front was demonstrated, and the influences of chemical agent on mobility ratio and displacement efficiency of steam flooding were analyzed. Then, according to the quality demand of mobility control agent, MCA was selected to be used as the agent to control the mobility of water phase in the process of steam flooding. Finally, laboratory simulated experiments on condensation water mobility control were carried out. The results showed that, when the core was saturated by MCA with a saturation of 1%pv, the permeability of the core was decreased to about 20% of the initial value; with the MCA was gradually dissolved and swept out of the core, the saturation decreased and the permeability recovered gradually, the permeability can return to above 93% of the initial value, showing that the permeability reduction caused by the crystallization of MCA is temporary and invertible. When displaced by about 2pv, the average efficiency of the displacements without addition of MCA was 53.24%, while the average efficiency of MCA added displacements was 61.25%, the application of MCA can increase the efficiency of the linear displacement experiments with a value about 8% of the OOIP averagely.Thirdly, catalysis system for heavy oil in-situ upgrading was prepared and evaluated. First of all, the possibility and reinforcement of viscosity reduction by aquathermolysis of Liaohe heavy oil were investigated. The results showed that after aquathermolysis for 24 hours at 240℃, the viscosity reduced 7.26%, and the content of saturated hydrocarbon and aromatic hydrocarbon increased, while the content of resin and asphaltene decreased a little; oil sands can increase the viscosity reduction of the reacted heavy oil about 1 time; 0.3% ferrous sulphate together with oil sands can decrease the heavy oil viscosity by 55.02%, and after the aquathermolysis under the action of tetralin and oil sands, the viscosity reduction of heavy oil can increase about 40%, showing the Liaohe heavy oil can occur aquathermolysis, and the catalyst and hydrogen donor can reinforce the viscosity reduction by aquathermolysis. Next, the main agent of in-situ upgrading catalysis system was developed with nickel and cobalt contained minerals. The performance evaluation showed that the thermal stability of the developed catalyst is good, it is compatible with formation water, and has coordination with reservoir minerals; methylbenzene or mixed benzene was selected as the hydrogen donor for the catalytic aquathermolysis; sulfonic acid anionic surfactant was selected as the auxiliary agent to gain further improvement on the in-sity viscosity reduction. The formula of catalysis system developed is 0.2% cobalt/nickel oleate mixture,1.0% mehtylbenzene,0.3% mahogany sulfonate. Finally, the results of laboratory evaluation on the catalysis system developed showed that after aquathermolysis with the action of catalysis system, the quality of heavy oil is upgraded, the content of saturated hydrocarbon and aromatic hydrocarbon increased, while the content of resin and asphaltene decreased obviously, the content of carbon in heavy oil decreased, while the content of hydrogen increased, and the content of sulphur decreased markedly, the viscosity decreased inconvertibly with a viscosity reduction ratio of about 90%, as a result, the mobility of the heavy oil was improved.At last, the implementation program for field application of mobility control agents was preliminary designed. More work should be done in the future to optimize the injection volume, injection time and injection pattern and so on.更多还原