Natrium-Calcium Double Alkali Flue Gas Desulfurization

Working principle:

Using natrium radical desulfurizing agent to progress desulfurization in the tower, the products after desulfurization with Ca(OH)2 to restore and regenerate, Regenerated absorbent can be recycled. Due to strong alkalinity natrium radical desulfurizing agent, reaction product has high solubility after absorption of SO2, won't causing problems of over staturated crystallization and equipment fouling blockage. Lower investment and operating costs is more suitable for small and medium boilers desulfurization conversion.

Chemical reaction:

2NaOH+SO2→Na2SO3+H2O

Na2SO3+SO2+H2O→2NaHSO3

Ca(OH)2+Na2SO3→2NaOH+CaSO3

Ca(OH)2+2Na2HSO3→Na2SO3+CaSO3·1/2H2O+1/2H2O

In the presence of oxygen, the following reaction will occur:

Ca(OH)2+Na2SO3+1/2O2+2H2O→2NaOH+CaSO4·H2O