Profile Control By Water Plugging Technology Research And Application In Xifeng Oilfield

The develop of Xifeng Oilfield has gradually turn into high water cut development period,and fingering and coning phenomenon occurs when the injection water flows along with the high permeable zone,large pore paths,fractures. This leads to the connection between oil well and injection well,reduce the water-flood efficiency,and aggravate the contradiction of injection-production. In order to raise the water-flood efficiency and alleviate the contradiction of injection-production,water shut-off and profile control becomes one of the main technical measures in the oilfield development.First,based on the analysis on geologic features of Xifeng Oilfield,such as reservoir characteristics,pore fluid property,and pore types this paper obtains the laws and types of water breakthrough in Xifeng Oilfield,considering the current development situation and contradictions. In addition,this paper studies the technology of well selection used in Xifeng Oilfield and theoretically analyzes the applicability of the PI well selection decision-making technology and IPI well selection decision-making technology for the low permeability of Xifeng Oilfield reservoir combining with the application effects. It suggests that the two technologies should be combined to make the decision of well selection according to the actual conditions. Last,by the analysis on the field applications of water shut-off and profile control in recent years in Xifeng Oilfield,the weak gel profile control system is selected from several popular profile control systems to conduct a series of laboratory experiments. It shows that this system has good static performance and sealing property,but its weak injectivity need be improved by lowering the concentration of polymer. So the deep profile control applicability of the system in Xifeng Oilfield should be discussed further. Currently,no water shutoff agent has an overwhelming advantage against others and every agent has its own advantages and disadvantages. In a comprehensive view,it is of great importance to select proper wells as the profile control object,adopt reasonable profile schemes,take effective measures,use scientific and reasonable slug composition and composite applications of plugging agent.