Experimental And Theoretical Study On Multilevel Slurry Jet FGD

There are many control technologies of pollutant SO2 discharged by coal-fired boiler at the present time, including of wet lime/limestone-gypsum flue gas desulfurization(FGD), which is the most effective FGD technology and used in many fields. Slurry jet FGD is one of the advanced FGD technologies, charactered by strong gas-liquid turbulence mass transfer, credible operation and high-degree desulfurization. In the thesis, a new style multilevel Slurry jet FGD is carried out in order to decrease its capital cost and operation cost.There are several parts in this work. An experimental platform is designed to study the liquid-column spraying characters. Another one is designed for studying desulfurization characters.The flow field characteristic in multilevel Slurry jet scrubber, such as the diameter and velocity distribution of atomized slurry droplets have great effect on desulfurization. Spray experiments are carried with different type nozzles. The distribution of drop size are measured by using slides with film and PIV technology. The experiment data is fitted by Rosin-Rammler empirical formula. It has good agreement in certain ranges.The pressure drop and desulfurization characteristic of multilevel Slurry jet scrubber are studied. The effects of slurry flux density and flue gas velocity on the resistance in the scrubbers and the effects of slurry flux density, flue gas velocity, circulating tank pH, and SO2 inlet concentrate on desulfurization in the scrubbers are studied.On the basis of multiphase fluid dynamics, turbulent diffusion and mass transfer theory, the liquid-gas mass transfer model in scrubber is set up. The effect of slurry flux density, flue gas velocity, droplets diameter change and distribution on flow field distribution are taken into consideration, the droplets'tracks are simulated by CFD method. In order to improve the distribution of flow field, the geometry of tower entrance is optimized. The calculated results agreed well with the test results. The results may give some directions on the further study of the new style multilevel Slurry jet scrubber.