Synthesis And Evaluation Of New Salt Blocking Agent

At present, most of oilfields have stepped into high-aquifer stage in our country. Owing to the presence of anisotropy strata, the quantity of water rising year after year, oil production depress year after year. Oil well exclusion of water and injection well injection profile controlling has been the important measure of enhancing recovery of crude oil. Especially, toward high salinity oil well, exploiting salt-tolerance water shutoff agent particularly attaches most importance. When touching water, the water shutoff agent will swell. In high concentration brine, the expansion ratio is yet higher. It can improve the sweeping coefficient of injecting water and ameliorate water-injecting profile of stratum. So it can improve the recovery of crude oil.In this paper, by filtering the dispensation of water shutoff agent, the water shutoff agent characteristic of salt tolerance has been enhanced, high intensity after absorbing water, high water-intake velocity. In the course of experiment, using primarily the expansion rate of water shutoff agent in the salt solution evaluate characteristic of water shutoff agent. Finally, the best monomer ratio quantities, initiator dosage, cross-linking agent dosage, neutralization degree of acrylic acid and reaction temperature have been ascertained. After ascertaining the best dispensations of water shutoff agent, the physical properties and chemical properties (such as expansion ratio, built up rate, co -efficient of resistance and so on) of water shutoff agent have been evaluated. Experiments prove that the physical properties and chemical properties of water shutoff agent are better.The result of core flooding experiment show that water shutoff agent have better performance of thermo-stability, rheology, intensity, good injection and selection, depressing the permeability of high infiltrative stratum, having a high blocking rate, modifying water the profile well, increasing the volumetric sweep efficiency of injecting water.