Abstract
Reservoir heterogeneity, along with the oil to water viscosity ratio, cause fingering and water breakthrough along fractures or higher permeability layers of in water flooding oilfield. This in turn decreases the water sweeping volume and water drive effect, making the medium or lower permeability layers poorly productive or even unproductive. As a result, the production wells will be flooded before due or will have a rapidly increased water-cut. Blocking higher permeable layers with chemical reagents along the flow direction of water can efficiently increase the water-affected volume; adjust productive and absorptive sections of the reservoir. Therefore, the water-cut can be decreased, the oil production can be increased, and the objective of stable oil production and lower water-cut can be achieved. This paper presents the techniques used in a field test project conducted at Daqing Oilfield. Granular gel-polymer was used as blocking agent. Economically improved oil production and reduced water-cut were observed.