Study On Numerical Simulation Of Steel Slag Carbonation Reaction

BOF slag is the solid by-products of steelmaking. Because of adjusting slag basicity in the process of steelmaking, the free calcium oxide (f-CaO) be left in slag. To some extent, these free calcium oxide limit the application of slag in various fields.In this paper, In order to explore the new method of digestion free lime and develop new areas of application, the source, formation, distribution of free calcium oxide in slag be discussed. The carbonation reactions of steel slag have two functions. On the one hand, CO₂ gas and free lime in slag react firstly, and then generate to be the carbonate material. So the stability of steel slag is strengthened, and the application fields can be expanded. On the other hand, slag can be used as adsorbent of CO₂, and CO₂ can be fixed. Thus, the dual role is achieved: digesting free calcium oxide in slag and fixing CO₂ gas. It has profound significance for reducing CO₂ emission and green metallurgical.The carbonation reaction of digesting free calcium oxide is gas-solid two-phase reaction. In order to achieve the coupling among flow, mass transfer, heat transfer and chemical reaction, the model of gas-solid two-phase flow and reaction through the UDF function be establish. Then we find out the velocity contours of corresponding instantaneous, the flow pattern of solid particles, temperature field of gas-solid, and the mass fraction of f-CaO transient changes. By changing the boundary conditions we have different reaction results.