Experimental Study on Removal Characteristics of SO3by Wet Flue Gas Desulfurization Absorber

This paper reports a study on the simultaneous removal characteristics of SO3in a wet flue gas desulfurization (WFGD) system. The impacts of the operating parameters, including liquid-to-gas (L/G) ratio, inlet SO3concentration, flue gas temperature, superficial velocity, and slurry temperature, on the SO3removal efficiency and SO3aerosol characteristic were studied. Results showed that the overall SO3removal efficiency varied from 20% to 55% under the experimental conditions. For the SO3aerosol, particles measuring <0.1 μm and >0.5 μm had a higher removal efficiency, whereas particles measuring 0.1–0.5 μm were relatively difficult to remove in the WFGD system. Increases in L/G ratio and SO3concentration exerted positive effects on the SO3aerosol capture, whereas superficial velocity, flue gas temperature, and slurry temperature had negative effects. After installing a sieve plate, the SO3removal efficiency increased from 49.88% and 53.46% to 51.77% and 58.05%, respectively, under two typical conditions. A multilayer perceptron artificial neural network model was applied to evaluate the relative importance of each parameter in SO3removal performance. Results showed that inlet flue gas temperature, inlet SO3concentration, and slurry temperature had a relatively strong impact on SO3removal performance.