Study and application of separate layer sand control and separate layer oil production technology in offshore unconsolidated sandstone reservoir

The unconsolidated sandstone reservoirs in Shengli offshore are characterized by many oil layers, long well sections, large interlayer, strong inter-layer heterogeneity and easy to produce sand. At present, offshore unconsolidated sandstone reservoir wells are using electric pumps and combined production, hence the inter-layer contradictions are prominent, which can not play fully role of each producing layer, restricting the development of offshore oil fields. Therefore, it is necessary to study separate layer sand control and oil production technology of electric pump well for 7 in casing production in Shengli offshore. Aiming at the problems of uncompaction and small diameter of general sand control method, a large diameter separated-layer sand control pipe is developed, which realizes separated-layer sand control and the following separate oil production. The oil and water swelling packer is designed to realize the stratified production. Through the design of on-line electric regulating valve, the flow of each layer can be adjusted. The technology has been tested in three Wells: CA2*-*, GO2-17-* and GO4-19-*. All the tests are successfully implemented, the water cut has been reduced to a certain extent, and the average daily oil is increased. It has achieved good results and will be applied more widely in offshore oil fields in the next step.