Popis: |
An onshore oilfield, located in the northeast of Brazil, is being submitted to a microbial EOR method to reduce problems associated with high permeability zones. Ten water injection wells were selected to the field trial. The method consists in the dosage of nutrients and an electron acceptor in the injection water, in order to stimulate microorganisms to produce biomass and biopolymer to plug high permeability zones. Pressure, flow rate and injectivity profile are being monitored. The results demonstrated that the process is effective. Five wells indicated the plugging of the high permeability zone, due the pressure increase and flow rate decrease. Only three of these wells were evaluated by injectivity profile, and two of them presented improvements on the vertical sweep efficiency. |