Development and Application of the Water Control and Profile Modification Technology in China Oil Fields.

Abstract

Liu Xiang-E Research Institute of Petroleum Exploration and Development (RIPED) China SPE Member Abstract This paper presents the research, development and field application of the water control and profile modification technology in China. It discusses on the mechanism of chemical water plugging and profile modification as well as matching techniques and the economic benefits in oil fields application. Introduction Since 80's, most of water flooding oilfield in China gradually step into the stages of moderate-high water cut. Previous technologies for early development stage of oil fields are no longer suitable for the present development of oil fields. It is critical and key technical problem to develop a new improved water flooding technology to stabilize and increase crude oil production in developed oilfields, for now and future. The aim of improved water flooding technologies is to increase the sweep efficiency and fluid production rate, length the stable oil production period and finally to increase the water flooding oil recovery efficiency. The historical data during the production of sandstone and limestone reservoir demonstrate that water control and profile modification technology is one of the important techniques for increasing the sweep efficiency of water flooding. From 50's to today, the research and application of water control and profile modification technology in China oil field experience three stages: the 1st, mechanical water plugging (from 50's to the later 70's); the 2nd, chemical water plugging (from the early 80's to the middle 80's); and last comprehensive treatment for profile modification in injector and water control in producer of blocks in oil fields (from the middle 80's to today). More than 20,000 well treatments have been carried out in oil fields from 1979 to 1993. The good production results from water control and profile modification have been achieved, such as the increase of recoverable reserves and oil production and decrease of water production and so on. The significant economic and technical benefit have been achieved. (see Table 1 and Figure 1). PHYSICAL MODEL AND MATHEMATICAL MODEL STUDY OF POLYMER GEL PLUGGING AND PROFILE MODIFICATION MECHANISM Using micro-model technology and nuclear magnetic resonance & imaging (NMRI), RIPED has studied polymer gel filling, immigrating and plugging mechanism in porous medium. P. 181