Tianfu Xu is a Staff Scientist (终身研究员) at the Lawrence Berkeley National Laboratory (LBNL), which he joined in 1996 initially as post-doctoral fellow. He received a bachelor’s degree in 1984 from Jilin University of China, an M.S. degree in 1993 from Delft University of Technology of The Netherlands, and a Ph.D. in 1996 from University of La Coruña, Spain. For the last 16 years, Tianfu has been working on developing new approaches to modeling multiphase non-isothermal fluid flow and chemical transport in unsaturated and saturated porous media and fractured rock systems. He is the chief developer of LBNL’s multi-phase non-isothermal reactive flow and chemical transport simulator TOUGHREACT. The program is among the most frequently requested codes in the library of the Department of Energy's Software Center, and is widely used nationally and internationally for CO₂ geological sequestration, nuclear waste disposal, geothermal energy development, environmental remediation, and increasingly for petroleum applications. Tianfu has authored and co-authored about 45 peer-reviewed journal papers. His papers have been cited by other researchers more than 400 times (SCI citation). In this talk, Tianfu will give an overview on the theory and numerical method used by the simulation tool, and then he will present reactive transport modeling examples ranging from CO₂ geological sequestration, to other energy and environmental problems.