The Performance Characterization And Research On The Chelate System Of Polymer And Cross-linked Polymer Microspheres

According to the characteristics of oilfield exploitation and the problems of polymer flooding and deep profile control technology in oil recovery,the experiment try to add a kind of cross-linking agent into the polymer and the polymer microsphere and use the cross-linking effect of cross-linking agent to make the molecular size larger.It can combine micro dynamic seal of the polymer microsphere on part of high permeability of the reservoir pore with the effect of reducing water-oil mobility of the polymer to achieve the purpose of improving oil recovery.Firstly,aluminium citrate cross-linking agent was prepared.Based on the test and analysis of membrane plugging effect from different dual cross-linking system,the best cross-linking agent,cross-linking rate and the polymer were chose,and the optimum condition was applied in ternary chelate system.The results of membrane plugging experiments show that the ternary aluminium chelate system has excellent membrane plugging performance under the conditions of using aluminium citrate cross-linking agent,polymer JZ9-3 and cross-linking rate of 20:1.Secondly,through the experiments of the particle size distribution and electron microscope scanning,the microstructure of the system was analyzed,the results show that the particle size distribution of the system is more wide with the form of intermolecular cross-linking "polymer-Al-polymer microspheres" partly.Again,through the experiments of viscosity,rheological properties and salinity effect,the results show that the ternary aluminium chelate system has stable structure,complex flow pattern,high viscosity retention rate and strong salt resistance.Finally,through the simulation core displacement experiments to evaluate the oil displacement efficiency of the system,the results show that the system can effectively increase the oil displacement efficiency and enhance oil recovery.