Fracturing Of Viscoelastic Surfactant Synthesis And Their Structure And Properties Of Study

Fracturing operations were main measures of improving production capacity of low penetration oil/gas reservoirs currently. Fracturing fluids used as medium of hydraulic fracturing, took the function of transmission pressure, suspended proppant and extends the newborn crack in the fracture process and played the very important role in success ratio, in stimulation scope and in stimulation cycle of oil/gas well after fracturing. At present it became a hot topic that developed the low penetrating oil/gas reservoirs, specially to develop the low penetrating gas reservoirs. Because clear fracturing fluids had a low damage, it became a hot topic to study of fracturing fluids, and it was a effective method for solving fracturing's demage in gas reserviors.The theory of VES solution and the feasibility of sold surfactant used as VES were researched. Two molecule structures: esterifiable ammonium salt and N-alkyl-N,N-bis(2-hydroxyethyl) octadecyl ammonium bromide cation surfactants were designed. The synthesized research to two kinds of molecule and obtained their reaction conditions.The synthesized visco-elastic surfactants had some surfactivity, and they had lower cmc. The different of purified products and crude products were ob vious. Appended NH₄Cl that influenced more faint to synthetical products solution, appended KBr had a few of influence to synthetical products solutions, and Appended NaSyl that increased solution's visco-elasticity of 18-2-2-1 remarkably. Though altering dosage of synthesized goods and salt, confirmed clear fracturing fluids composes fit for a series of temperatures.Capability appraisement indicated that all of these fracturing fluids had well ability of bearing cut. The vicosity ≥72% at 170s^-1shear two hours, the viscosity <5.0mPa.s after breaken, it illuminated that the system had a well broken abilities, and the system hadn't residues. The sedimentation rate of proppant in the fracturing fluids was 0.027～0.055% in water, it illuminated that the system had a well suspending propant abilities.Miscro-analsis was procesed for the crossed linked HPG fracturing fluids and polymer KTU-43 fracturing fluids and clear fracturing fluids, and analysed cause of fornation of theirsloves visco-elasticity...