ABSTRACT
Flue gas desulfurization (FGD) is now popular in the United States, Japan, Germany, Austria, the Netherlands, Sweden, Taiwan, and elsewhere, and has begun to be used in many other countries. Still, annual world S02 emissions have increased to 140 million tons due to the increase in most developing countries (Fig. 1). To alleviate acid rain problems, a further S02 reduction of about 40 million tons/year may be desired. so2 may be reduced considerably by the switch from high-sulfur to low-sulfur fuels, but the need for FGD may become greater as coal consumption increases. In the past, nearly 30 million tons/year of S02 has been emitted in the United States (Fig. 1). Under the Clean Air Act, S02 from coal-fired boiler flue gas is to be reduced by 10 million tons/year.
