Pilot Test Research And Application Of Binary Flooding In Guan109-1 Fault Block Of Zaoyuan Oilfield

Petroleum is known as the blood of industry and plays an important role in the process of global economic development.How to recover the residual oil after water flooding as much as possible has become a difficult problem in the process of production,so the research and application of chemical flooding technology is imperative.After nearly 12 years of development,the water cut of Guan 109-1 fault block reaches 87.3%,and has entered the late stage of high water cut development.However,the recovery degree is only 7.11%.The distribution of remaining oil is dispersed,which is the best period of tertiary oil recovery.Firstly,this paper introduces the geological development characteristics of Guan 109-1 fault block in Zaoyuan oilfield,studies its structural characteristics,reservoir characteristics,rock wettability,reservoir description and so on,and analyzes the residual oil potential of waterflooding.On this basis,combined with the characteristics of high temperature,high salinity and medium-low permeability reservoir in Guan 109-1 fault block,chemical flooding test is carried out in this block,which will explore a new technical way to improve oil recovery and development effect of this kind of reservoir.In order to optimize the binary flooding system suitable for high temperature and high salt reservoirs,a variety of polymer and surfactant reagents were collected at first,and their basic properties were screened and evaluated through a large number of laboratory experiments.After comparative analysis,the main reagents were identified as associating polymer AP-P3 and surfactant PS-001.Associated polymer has the characteristics of low molecular weight,high viscosity,high temperature resistance and high salinity resistance,which meets the needs of high temperature and high salinity reservoirs in Guan109-1 fault block.The compatibility of associating polymer AP-P3 and surfactant PS-001 was also evaluated.The results showed that the binary system had good thermal stability,shear resistance,adsorption resistance and oil washing ability.The pilot test solved the key difficulties of chemical flooding in high temperature,high salinity and high viscous reservoirs.By adopting the method of "aeration+chemical method",the field sewage was removed iron and sterilized.At the same time,associative polymers with strong salt resistance were selected to alleviate the degradation reaction of polymers and improve the temperature and salt resistance of binary systems.Finally,it provides a way to improve oil displacement efficiency for medium-low permeability and heavy oil.In field application,in order to verify the compatibility of binary flooding system screened by previous laboratory experiments with Guan 109-1 high temperature and high salt reservoir and the reliability of related injection allocation technology,a single well injection test was carried out for Jiaxin 45-7 well in the test area.The binary system of"associating polymer+surfactant" has a good compatibility with the sewage from Jiawu Station,and the thennal stability of the system is high.The wellhead viscosity and the viscosity of the backflow fluid meet the design requirements of the scheme.In December 2016,the binary flooding dispensing station was fully injected(7 injection 12 production),and the system indexes met the design requirements.Through field application,the related chemical flooding matching technology was formed.Now,350,000 cubic meters of binary flooding system has been injected.Up to now,108,000 tons of oil has been increased.