Blast furnace (BF) is the predominating process for hot metal production, featured by high energy consumption and CO2 emission. A CFD based BF process model is further developed and validated at various levels. It is then used to study different strategies for improving BF process efficiency. This includes optimization of burden distribution and inner profile, the implementation of burden hot charge and developing oxygen BF ironmaking process. The applications prove that the model can be used not only for a better understanding but also for design and control of the BF ironmaking process.