Experimental Research On Enhanced Oil Recovery-Combined Microbial And Polymer Method

The recovery of oil by water flooding is low in China's oil fields, because most of which are continental sediments and they have complicate formation conditions. In recent years, exploration of most oil fields in East China, especially that of the Daqing Oil Field, has entered into their later high water cut development period. Tertiary oil recovery technology, such as chemical and microbial methods, is widely applied there. However, every kind of oil recovery technology has its own limitation. Research on effective and economical ways to recover the large amount of residual oil has been studiously carried out by many experts and specialists in the field of petroleum engineering.In China, microbial enhanced oil recovery (MEOR) has been used in exploration of continental sandstone oil field and has shown relatively good result. However, due to the high heterogeneity of this type of geological structure, the injected microbial fluid will tend to go into the more porous space with less oil contents; therefore, MEOR has not fully achieved its desired effectiveness.Hence, in order to maximize the full economic benefit of MEOR, based on the actual application of MEOR in the oil field, in this thesis, the author presents the new technology of combined microbial and polymer method, and attempts to validate its effectiveness through literature research and analysis and laboratory research.The results show that the compatibility between selected microbes and polymers was good and that such combinations might be beneficial to enhancing oil recovery. Therefore, it is concluded that the scheme of combined microbial and polymer method should be further developed through more research and experimental work, so that it can be practically used in oil production in the future.