Mechanism And Method Of Deep Profile Control With Controllable Self Aggregation Colloidal Particles

In order to better study the treatment methods of water channeling in heterogeneous oil reservoirs,this paper mainly studies the profile control and plugging method based on controllable self-aggregating colloidal particles.By comparing the displacement effects of colloidal particle and foam flooding in heterogeneous oil reservoirs,analyzes the performance advantages of colloidal particles in the process of profile control and displacement in heterogeneous reservoir.A composite profile control and oil displacement agent is proposed to improve the controllable self aggregation colloidal particles.Firstly,the performance evaluation of the controllable self-aggregation colloidal particles is carried out to obtain a water-soluble colloidal particle with good dispersibility,temperature resistance,low expansion and self-aggregation characteristics.The colloidal particle can self-aggregate into colloidal particle clusters with a diameter of more than three times,the dispersed colloidal particle solution has good injectability in the reservoir and the ability to selectively block water channeling channels in heterogeneous reservoirs.It found that the parameters of affect the plugging characteristics include injection rate,pore length,colloidal particle concentration,and pore size through the experiment.it is recognized that the controllable self-aggregating colloidal particles have three processes in porous media:dispersed flow,self-aggregated migration,and blocked aggregation under the visual etching model and core slice analysis method.After the colloidal particles injected into the porous medium aggregate into colloidal particle clusters,the residual resistance coefficient can reach more than 1.83,and more than 60%of colloidal particles will remain in the core durig the process of colloidal particles flowing through the core.The colloidal particles in heterogeneous cores can increase the oil recovery by 12%-16%,and the effective permeability plugging rate is 45%-76%.By comparing the different methane injection methods and displacement effects in low-permeability and ultra-low-permeability heterogeneous cores,it is found that methane non-ionic foam flooding can improve the oil-water mobility in core pores,and can effectively inhibit water channeling in the low permeability heterogeneous core.Foam flooding can increase the swept volume and microscopic oil displacement efficiency.Foam flooding improves the oil recovery of low-permeability heterogeneous reservoirs by 11%-18%.The foam flooding has high residual resistance coefficient,and the plugging rate is more than 80%.A composite profile control oil displacement agent is obtained by adding TIECC agent to the colloidal particle solution,the colloidal particles preferentially enter the high-permeability channel in the heterogeneous reservoir to prevent water channeling,so as to increase the swept volume of injected water.The TIECC agent will percolate into the small pore space of the low-permeability layer under the action of high displacement pressure difference,exerting its high efficiency of oil displacement characteristics to improve the microscopic oil displacement efficiency.Finally,the recovery rate of profile control and flooding reaches 14%～25%,the residual resistance coefficient is 2.77～9.46,and the plugging rate reaches more than 70%;The main controlling factors affecting the effect of composite profile control and displacement agent are obtained by grey correlation degree analysis:average permeability of heterogeneous reservoirs,permeability gradient,particle size of colloidal particles,concentration of colloidal particle solution,slug size of injected profile control agent,the speed of injecting profile control and displacement agent and the content of the TIECC agent in the colloidal particle solution.Based on the gene expression programming algorithm,a set of prediction models are established to obtain the relationship between the profile control and displacement recovery factor,residual resistance coefficient and plugging rate of the compound profile control and displacement agent and the seven main control factors.,which can be used to quickly and accurately predict the evaluation effect of water channeling control under different heterogeneous reservoir conditions and different profile control and displacement agent parameters.