Study On Stabilization Mechanism And Plugging Effect Of Fly Ash Three-phase Foam

The energy issue is the focus of common concern in today's world.In China,the contradiction between energy supply and demand is particularly prominent.In recent years,China's oil dependence has been increasing,and improving the efficiency of oil and gas development has become the focus and hotspot of China's oil and gas industry.Most of China's oilfields have entered the middle and late stages of development,with increased water content and strong heterogeneity.Traditional oil displacement systems cannot further improve oil recovery.Therefore,there is an urgent need for a technology to change the status quo.In view of this,this paper uses the Warning Blender method and uses sodium ?-olefin sulfonate(AOS),sodium dodecyl benzene sulfonate(SDBS),dodecyldimethylamine(BS-12),phenol polyoxyethylene ether(OP-10),sodium soil and fly ash in order to get a high performance three-phase foam system.It is found that AOS has the best compatibility with fly ash.When its concentration is 0.5wt%,pulverized coal the ash to sodium soil concentration ratio is 2:1,and the solid phase concentration is 5.0wt%,the three-phase foam has the best foaming performance and foam stability.The three-phase foam stability mechanism is studied by using an interfacial tension meter and a stability analyzer.The results show that the larger the foaming agent concentration,the smaller the interface expansion modulus,but the foam stability increases first and then decrease with the increase of the foaming agent concentration.This is because when the concentration of the foaming agent is low,the foaming agent monolayer adsorbs on the solid particles,the hydrophobic group is outward,which changes the wettability of the solid particles,improves the particle interfacial dispersing ability,and the foam stability is enhanced;When high,the foaming agent forms a double-layer adsorption on the surface of the particles,and the hydrophilicity is enhanced,and at the same time,the foaming agent forms a competitive adsorption with the solid particles at the interface,and the foam stability is weakened.The higher the solid particle concentration,the stronger the foam stability.The increase of solid phase concentration not only increases the bulk viscosity,but also increases the adsorption amount of solid particles at the interface,and the strength of the interface film increases.Scanning electron microscopy and particle size analyzer are used to study the morphology and particle size of the particles before and after mixing.The results show that the particle size of sodium soil is smaller than that of fly ash.In aqueous solution,the sheet structure formed by sodium can be uniformly coated on fly ash particles.On the surface,the particle dispersing ability is enhanced,and the gas/liquid interface film strength is enhanced.The results of core displacement experiments show that the fly ash three-phase foam is not easy to rupture in the formation,and has a good sealing effect.With the increase of the total solid phase concentration,the plugging performance is better.