Study on the technology of wet dedusting of flue gas from medium and small coal-fired boilers

According to the characteristics of flue gas from medium and small coal-fired boilers, a new type deduster SCC-rectangleis developed. This paper introduces the structure and dedusting mechanism of SCC-rectangle. The deduster adopts the structure of turbulent ball tower. The principle of fluidized bed and the double-film theory are applied to the gas-liquid mass transfer apparatus. In the moving of gas and liquid, gas film, phase interface and liquid film are formed when gas contacts with liquid. At the same time, the relative moving of gas and liquid makes filler in the state of fluidizing and turbulent flowing successively. Dust moves from gas film to phase interface, then to liquid film, eventually to the interior of liquid by turbulent diffusing. Furthermore, the larger gas-liquid contact area forms by innumerable bubbles produced by washing liquid and plastic ellipsoid, and the high turbulent extent. Thus, the gas film mass transfer resistance is less, the gas, liquid and solid contact is consolidated. Therefore, the purpose of dedusting is realized. Based on it, the cold test was made. The results showed that under the condition that the static altitude of filler is 180 mm, the liquid-gas ratio is not more than 0.8 L/Nm(3), the dedusting efficiency is more than 99.5%, and the device pressure loss is less than 1 000 Pa. The requirement of efficiency and resistance of wet deduster is reached completely.