Flue-gas desulfurization

Flue-gas desulfurization (FGD) is a set of technologies used to remove sulfur dioxide (SO
2) from exhaust flue gases of fossil-fuel power plants, and from the emissions of other sulfur oxide emitting processes.

As stringent environmental regulations regarding SO₂ emissions have been enacted in many countries, SO
2 is now being removed from flue gases by a variety of methods. Below are common methods used:

For a typical coal-fired power station, flue-gas desulfurization (FGD) may remove 90 percent or more of the SO
2 in the flue gases.

Methods of removing sulfur dioxide from boiler and furnace exhaust gases have been studied for over 150 years. Early ideas for flue gas desulfurization were established in England around 1850.

With the construction of large-scale power plants in England in the 1920s, the problems associated with large volumes of SO
2 from a single site began to concern the public. The SO
2 emissions problem did not receive much attention until 1929, when the House of Lords upheld the claim of a landowner against the Barton Electricity Works of the Manchester Corporation for damages to his land resulting from SO
2 emissions. Shortly thereafter, a press campaign was launched against the erection of power plants within the confines of London. This outcry led to the imposition of SO
2 controls on all such power plants.

...
Wikipedia