Pilot Test for Nitrogen Foam Flooding in Low Permeability Reservoir

Abstract

Due to the characteristics of reservoir formation, the producing level of low permeability reservoir is relatively very low. It is hard to obtain high recovery through conventional development schemes. Considering the tight matrix, complex fracture system, low production level of producers, and low recovery factor of M block in Xinjiang oilfield, it is selected for on-site pilot test of nitrogen foam flooding. Detailed flooding scheme is made and the test results are evaluated respectively both for producers and injectors. The pressure index, filling degree, and fluid injection profile are found to be all improved in injectors after injection of nitrogen foam. The oil production, water cut and liquid production file are also improved in most of the producers, with the natural decline rate in the test area become slow. Results show that nitrogen foam flooding technology can be good technical storage for enhanced oil recovery in low permeability reservoir.