| The study of adsorption behavior of asphaltene on quartz sands and wettability characteristics due to adsorption of asphaltene and physical chemistry percolation under different wetting condition,involves in Surface Colloidal Chemistry,Analytical chemistry,spectrum organic chemistry,physics,fluid mechanics,et al. It also relates to multi-discipline basic theory research as well as industrial technologies on petroleum engineering,geology,electron microscope,environmental engineering,pedology and so on.Improving crude oil production depends on thorough understanding about the interaction between reservoir fluids and rocks. Adsorption and wettability study can benefit that. Now,the understanding about adsorption phenomenon of crude oil /brine /rock system,and the relationship between adsorption and wettability as well as the relationship among adsorption,wettability and recovery is very insufficient. As for the micro-displacement mechanism on the different wetting reservoir,much work is required.The aim of this paper is to explore and develop a new way to understand the adsorption behavior and adsorption mechanisms,wettability change due to asphaltene adsorption,and further displacement mechanisms and recovery change according to different wetting reservoirs. Much effort is taken to promote and consummate recovery theory and reservoir mathematical simulation.The following four aspects are highlighted in this paper. The first one is about the research on adsorption behavior,adsorption characteristic and covering degree under different experimental condition. The second is about wettability measurement of quartz sands due to adsorption of asphaltene and resin. The third is about the cause of wettability change. And the last is about the dynamic simulation and displacement mechanisms of water driving air,oil driving air,oil flooding,water flooding,NAPS polymer flooding,NAPS polymer flooding after water flooding and miscible displacement in different wetted cores filled with quartz sands adsorbed by asphaltene.The primary achievements of the paper are:1. A series of research area is developed,including the adsorption of asphaltene and resin on quartz sands,wettability research,and physical-chemicalpercolation in porous media under different wetting condition.2. Kerosene is employed as a solvent for asphaltene and resin,not toluene because of its virulence. It's proved that asphaltene and resin coexist in a colloid under certain concentration and a special method is established to measure adsorption by adsorption isotherm.3. Distribution and size of asphaltene micelle is measured with fluorescence microscope.4. Adsorbed state of asphaltene on quartz sands is observed microcosmically with electron scanning microscope and adsorption mode is then deduced,which explains why the wettability of quartz sands changed into mixed wettability from strong water -wettability.5. Feasibility of wettability measured by n-heptanol method is proved,which not only adapts to quantitative oil-wetted percentage measurement for quartz sands or other grains,but also for the cores.6. It's found that the whole flowing network remains unstable with the change of flooding condition through studying fluid displacement under certain wetting condition.7. A new phenomenon is observed that new type polymer displaces oil in a changeable piston mode (the shape of the interface changed with pore size).8. Displacing oil after water flooding,polymer moves through water-flow channels in fingering. Simultaneously,polymer displacement can extend sweeping areas continuously.9. Oil miscible flooding tests show that even for single-phase flow of oil,oil flows through only certain channels and once the tunnels are created,they will keep constant.10. Intermittent water or polymer injection can greatly improve oil displacement efficiency.11. Microscopic immiscible displacement mechanisms are observed under different wetting conditions,which are jump mechanism,converting direction effect due to gas-in-oil,s...
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