Overview of Key Zonal Water Injection Technologies in China

Separated layer water injection is the important technology to realize the oilfield long-term high and stable yield. Through continuous researches and technological innovations, series separated layer water injection technologies have been developed to meet the technology needs of the different oilfield development stages to solve the interlayer problems, achieve high efficient of water injection, and solve the bottlenecks in different water injection stages. Oilfield water injection gradually comes to separated layer water injection, separate minilayer water injection and fine water injection stages from the early stage commingled water injection. Water injection technologies have experienced five main stages: commingled water injection, concentric water injection, eccentric water injection, integrated water injection and intelligent water injection. Every stage of the technology has played an important role for the oil field development. With the development of the separated layer water injection strings, downhole tools and supporting testing and conditioning technologies for the separated layer water injection, separated layer water injection technology has played an important role in evenly exploiting each reservoir and improving the producing extent of the bad reservoir. This technology has realized zonal production of the multilayer reservoir, and provided the technical support for keeping the oil production from the water flooding taking up more than 80% of the total.