| Wet lime/limestone-gypsum flue gas desulfurization (FGD) is one of many control technologies of pollutant SO2 discharged by coal-burning boiler by now. It is more effective and can be operated reliably. Liquid-column spray FGD is one of the advanced FGD technologies, performed by strong gas-liquid turbulence, easy maintenance and high desulfurization efficiency. The advanced study of liquid-column has important signification in optimizing the design of FGD system and reducing the cost, and also it is the base of modeling of the entire liquid-column spray FGD system.An experimental platform is designed to study the liquid-column characters by using spray conditions in actual engineering. Spray experiments are carried with nozzles which have different diameters. It has been analyzed the relationship between fluid flow, nozzle pressure, liquid-column height, diameter of liquid-column dispersal area, liquid-column dispersal angle, and measured the liquid distribution along the radial. The results show the nozzle with 30mm diameter has more advantages by compared the energy usage and the spray effect. Another experiment shows that the spray effect can be improved by using modified nozzle, which has grooves in nozzle inside.The second part of thesis is the analysis of liquid-column dispersal, including the continuous length of liquid-column and the stabilization critical velocity of different droplets. The drop size distribution was measured by using slides with film. Most drop diameters range from 100μm～200μm, about 90 percent of drop diameters is lower than 1mm, but large droplets, which have diameters higher than 2mm, are existed about 3 percent. The experiment data was fitted by Rosin-Rammler empirical formula, the result is . It has good agreement in certain ranges.Base on the characters size data obtained in experiment, the probabilitydistribution formula of drops is predicted by using maximum entropy theory. It has certain agreement with experiment data. It shows validity by using ME theory to predict the PDF of drops in liquid-column system.
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