Study On Profile Control And Oil Displacement Agent Of Temperature-tolerant And Salt-resistant For Xidaliya Oilfield

Aiming at the characteristics of the high temperature and high salinity reservoir in Xidaliya oilfield and the problem of dominant channels development and poor effect of water injection development,temperature-tolerant and salt-resistant profile control agents,including gel and gelled foam,are developed.In addition,basic performance and profile control and displacement property of profile control agents are evaluated,operation parameters is optimized,temperature-tolerant and salt-resistant mechanism of profile control agents is studied.According to the intensity of GSC code method,the gel system is optimized to 0.4~0.5% HTS polymer + 0.10% ~ 0.16% REL&MNE crosslinking agent,gel time range is 38~53 h,gel intensity range is E ~ H,applicable temperature lower than 110 ?with a little of dehydration after 60 days.On the basis of temperature-tolerant and salt-resistant characteristic,the gelled foam is optimized by Ross-Miles methods according foam performance evaluation index,and the appropriate ingredient of gelled foam is that 0.2%~0.3% HTS-1 foaming agent + 0.4%~0.5% HTS polymer + 0.06~0.16% REL&MNE crosslinking agent.Compared with the ordinary foam,foam performance is greatly improved of 2.2~2.4 times.The core flow experiment results show that the gel system,which has good shear resistance,good selective plugging capability for different permeability formation and good abrasion resistance,can improve oil recovery by 31.12% under the condition of Xidaliya recovery.Injection pattern of gel foam system for gas and liquid mixed note,best injection of gas and liquid ratio is 1:1,the best gas injection rate of 1 ml/min,selective plugging performance has the very good permeability,permeability plugging sex is stronger,the greater the scour resistant performance is good,indoor reservoir under the condition of improving oil recovery by 30%.It is found that the best injection mode of gel foam is gas-liquid mix injection,the best gas liquid ratio is 1:1,the optimal gas injection rate is 1.0 mL/min by the core flow experiment.The plugging performance of gel foam gets better with the growth of permeability in the range of certain permeability.The gel foam enhance the oil recovery by 30%.Ftir,DSC and SEM show that the main functional groups of gel including benzene ring,conjugated olefins,alcohols,fatty amine structure and a large number of phenolic hydroxyl and alcoholic hydroxyl,which guarantee the gel has ability to resist salt and bound water under high temperature.The gel can form stable network frame structure well at no more than 175 ? under high salinity,which will be more stable and strong with the concentrations of polymer and crosslinking agent rising.Interfacial rheological experiment,bubble scanning and microscopic examination shows that HTS-1 can form stable polyhedral bubbles,of which liquid membrane foam agent has good self-repair ability and can keep a certain thickness to resist Plateau boundary effect.The gel provides a thicker layer of protection for foam,maintains the space of foam stability,improve the strength and thickness of liquid film,reduce drainage and gas diffusion effect and make the foam more stable in high temperature and high salt conditions.