Sulphur dioxide absorbtion study in residual calcium carbonate suspension

Using a modified Lewis reactor we studied the sulfur dioxide absorption in different calcium carbonates suspension. The experimental results indicate that the residual calcium carbonate from NPK industry has a similar mechanism and the solid reaction products are the same as in the case of milled limestone and chemically pure calcium carbonate. Using dry and wet milling it was possible to increase the reactivity of the suspension prepared from waste, the kinetic curves exceed the curve of milled limestone. Adopting the enhancement factor's method, developed in gas-liquid reactive absorption, we demonstrated that the sulphur dioxide's absorption in carbonate suspension is possible to be described with the same model. The relative enhancement factor values calculated using the Hatta modulus (E= 1.7) approach the measured ones (E= 1.67-2.11).