1.3.2.7. - 1.3.2.9. Ammonium-cyclic, magnesite and sodium sulphite-bisulphite technology

Shmigol I.N., JSC "VTI"

1.3.2.7. Ammonia-cyclical technology

A chemical basis for this technology is a balanced reaction between the saluted sulfite and ammonium bisulfite and sulfur dioxide, removed from the furnace gases:

(NH₄)₂SO₃ + SO₂ + H₂O = 2NH₄HSO₃.

1.3.2.8. Magnesite cyclical technology

The essence of magnesite cyclical technology lays in binding of sulfur dioxide by a slurry of magnesium oxide:

MgO + SO₂ = MgSO_3.

1.3.2.9. Natrium sulfite-bisulphite technology

This method (also called - Wellman-Lord process) is similar to the ammonia-cyclical, but instead of ammonium salts, sulfurous natrium salts are used:

SO₂ + Na₂SO₃ + H₂O = 2NaHSO₃.