Experimental study of wet flue gas desulphurization with a novel type PCF device

Scrubbers are being widely used to remove the dust, sulphur dioxide and other harmful gases from coal-fired boilers. In this paper, a novel ‘wet-type’ desulphurization absorber, the PCF device (Chinese LOGO), was developed and studied through an experimental method. The mixture of air and SO2 was used as simulated flue gas and CaCO3-in-water suspension was used as absorbent. The results show that the PCF device has a good overall performance for FGD. Under moderate conditions employed, the content of SO2 in outlet flue gas can achieve a level much lower than that permitted, while the pressure drop is very small due to co-flows in preliminarily treating chamber and no venturi structure in inlet tube. Guide plates and self-excitation chamber can improve the SO2 removal efficiency by intensifying the mass-transfer and second purification. Some feasible process parameters are as follows: slurry pH value = 5.6–6.0, liquid–gas ratio = 8.7–10.4 L/m3, superficial gas velocity in inner cylinder = 3.5–4.5 m/s, and addition of Cl− (in the form of CaCl2) to the slurry (25 g/L) decreased the degree of SO2 removal about 13.12%.