Research And Application Of Layered Water Injection Technology In Deep Inclined Wells In Jidong Oilfield

Layered water injection technology is an important technology to solve the interlayer contradictions of heterogeneous reservoir, with improving waterflood sweep efficiency and keeping the production of oil field stablly. Eastern Hebei Nanpu oil field is the nearly saturated complex fault block oil reservoir with the shortage of natural energy; the water injection exploitation is a necessary means of beach oilfield exploitation. On the other hand, the oilfield exploitation mainly adopts artificial island cnooc land exploitation mode, the well type are mainly composed of directional well and deep deviated well. The wellbore structure, complex trajectory of wells and long span lead to separate injection tubing string are under the condition of poor sealing, making the test successful rate is low. Therefore separate layer injection technology is the key technology of injection. combining with related technical research results in China and abroad and according to the well bore structure and production characteristics, adaptability and field operation factors are taken into consideration fully, to determine the technical countermeasures of layered water injection.In this paper, based on the study of the layered water injection technology, the strong sensitivity of reservoir water flooding reservoir protection technology research have been developed, technology and supporting tools have carried out for the complex layered water injection well under high temperature, high pressure with laboratory test and oil field test research. The specific research works are as follows:(1) The layered water injection technology research of deep deviated well in China and abroad have been completed, and the technology present situation, main problems and technological exploitation prospects were concluded.(2) The research of layered water injection string technology have been conmpleted, and the layered water injection string have been established for the span of different points injection period, which improving the string sealing effectient and resistant of high temperature and pressure, meanwhile the working life of string have been enlarged.(3) The supporting technology research of injection string safe when running into and out the wellbore have been completed. A set of injection tools, with a small outer diameter, shorter length and the been strong in anti-collision have been designed, which can improve the reliability when the string was running into or out the wellbore; cut down the load of tubing strings and improve the reliability and safety; a safety joint was added on the tubing string, which increased the safety; the way of sections salvaged will decrease heavy repair when the string is locked.(4) After researching on the different well deviation layered water injection technology, a bridge type eccentric quantitative injection technology, concentric points injection technology and non-contact remote measuring injection technology have been established, which meet the requirements of deep deviated well and improve the efficiency of separate layer injection.(5) Laboratory and field test researches of separate injection process and related tools have been completed, the test results show that the parameters meet the design requirements.After researching on the layered water injection technology in this article, a new technology and a set of matching tools have been established for the high temperature and high pressure deep deviated well stratified waterflooding operation, which is more simple, reliable, efficient and safe than that in previous technologies.