Key Optimization Technology of Intelligent Layered Water Injection with Hydraulic Control in Bohai Oilfield

Abstract

Conventional hydraulic control intelligent layered water injection technology has shortcomings such as low accuracy of allocation, limited layered number, unsatisfying the requirement of slim hole and inability of monitoring of water injection downhole data. Based on the problems exposed in the application of in Bohai Oilfield, technical optimization research was carried out. A digital decoder is developed, the number of adjustment stages of flow control valve is increased, the large flow rate downhole flowmeter based on vortex street test principle is matched, and the layered allocation scheme is optimized. Thus the key optimization technology of intelligent layered water injection technology with hydraulic control in Bohai oilfield are formed. The optimized hydraulic control intelligent separate injection process can implement the maximum layer number of 6 layers, and the different size of flow control valves regulation stage are increased to 11 and 7 stages respectively. It can also meet the application requirements of 82.55 mm slim hole water injection well, and realize real-time monitoring of downhole data on the surface. After optimization, the system has been applied in 20 wells in Bohai Oilfield, which has stable and reliable operation, flexible nozzle adjustment, and real-time downhole data upload, accuracy more than 95%. Single well allocation cycle is cut down to 1 day. The application effect is good.