On the SO2 Problem in Thermal Power Plants. 2.Two-steps chemical absorption modeling

The modeling of the gas absorption in a new column apparatus for waste gases purification from SO₂, using twophase absorbent (CaCO₃/H₂O suspension) is presented. The process is realized in a three-zone column. In the upper zone a physical absorption in gas-liquid drops system is realized and the big convective transfer in the gas phase leads to a decrease of the mass transfer resistances in this phase. In the middle zone a chemical absorption in liquid-gas bubbles system takes place and the big convective transfer in the liquid phase leads to a decrease of the mass transfer resistances in this phase. The large volume of the liquid in the middle zone causes an increase of the chemical reaction time and as a result a further decrease of the mass transfer resistances in the liquid phases is realized. The third zone is the column tank, where the chemical reaction takes place only.