ABSTRACT
Sulfur dioxide is one of the six criteria pollutants. More than 70% of sulfur dioxide in the atmosphere is from fossil fuel combustion, especially from the stationary sources and 20% from industrial processes. This chapter deals with an introduction on the impacts, sources and rates of sulfur dioxide emissions as well an overview of emission reduction technologies. It presents chemistry of sulfur and sulfur oxides. Flue gas desulfurization (FGD) is the approach to remove sulfur oxides from flue gas. The chapter also presents several wet FGD technologies. It explains several dry FGD approaches. The chapter describes several alternatives to the end-of-the pipe emission reduction technologies. It analyses process selection and design calculations. The absorption process of Well-Lord scrubbing is identical to the main scrubbing loop of the dual-alkali in which a sodium sulfite solution is used to absorb sulfur dioxide to form sodium bisulfite.
