Abstract |
The report describes studies of SO2 absorption from flue gases by water and alkaline solutions in venturi scrubber processes, including recycle of the scrubbing liquor. It proposes mathematical models describing the process momentum, heat, and mass transfer for SO2-H2O, SO2-NaOH-H2O, SO2-CaO-H2O, and SO2-CaCO3-H2O systems. It generates equations relating total pressure, liquid velocity, SO2 concentration in the liquid. It solves these equations numerically for performance profiles, used to examine the effects of such operating variables as liquid flow rate and the concentration of alkali in the liquid phase on the absorption rate. It analyzes data from various size holding tanks and proposes mathematical models for the lime/limestone slurry process holding tanks. Finally, it combines these models to simulate the venturi/holding-tank system with closed-loop recycling of the liquor. It examines the sensitivities of such operating variables as the recycling liquor rate and the alkali makeup rate on the absorption. It qualitatively discusses such practical problems as oxidation of sulfite to sulfate and scaling of the solids. (Modified author abstract) |