SPE Lecture-June: Low Salinity Water Flooding in High Temperature Reservoirs

This lecture presents a systematic assessment of the potential of low salinity waterflooding for the Dong-He-Tang reservoir in the Tarim Oilfield, China. Contact angle measurement, spontaneous imbibition and core-flooding experiments were conducted to experimentally show the effect of low salinity effect in high temperature reservoirs (up to 140^oC). A surface complexation model was developed to interpret contact angle measurements and compared with DLVO theory predictions.

The parameters derived from laboratory experiments were used as input for reservoir simulation models to investigate the potential of low salinity water flooding in the reservoir using two layered box models and a history matched full field reservoir model. Findings show that low salinity water has the potential to accelerate oil production and improve displacement efficiency thus resulting in a higher recovery factor with only a fraction of pore volume of low salinity water injection. Implications of these findings, such as slug size, salinity of injected brine, non-uniqueness of derived relative permeability curves on field application will be discussed.

This lecture is novel in the following aspects. First, the potential of low salinity water at a very high reservoir temperature of 140^oC has been systematically investigated. Second, laboratory experiments show that low salinity water changes wettability towards more water-wet, which is consistent with the derivation of relative permeability curves using core-scale numerical simulation. Third, the potential of the low salinity water in such high temperature is assessed using reservoir simulation based on input for laboratory experiments.

Speaker: Dr. Sam Xie, Department of Petroleum Engineering,  Curtin University

Dr Sam Xie is currently a research fellow with department of petroleum engineering in Curtin. He is leading low salinity water-EOR research area, and teaching numerical reservoir simulation unit. He started his career in 2011 in the Research Institute of Petroleum Exploration and Development (RIPED) of China National Petroleum Corporation (CNPC) in Beijing, China. Sam had been heavily involved in Chemical-EOR and Low Salinity Water Flooding research and commercial projects funded by CNPC and Ministry of Science and Technology of China during the past four years before he left RIPED in early 2015. Sam has committed to the Joint Venture Project between CNPC and SHELL to expand the application envelop of polymer flooding in high temperature and high salinity reservoirs with combination of Low Salinity Effect. Sam holds a PhD degree in oil and gas field development engineering from China University of Petroleum (Beijing).