SOURCES OF SOX
NATURAL SOURCES
o Natural sources of sulfur dioxide include volcanoes and hot springs.
o Sulfur dioxide is also formed by the oxidation of hydrogen sulfide (H2S), a toxic gas that smells like rotten eggs.
o Oxidations occurs when hydrogen sulfide combines with the oxygen in air, hydrogen sulfide is released by marshes and other places on land and in oceans where biological decay is taking place.
ANTHROPOGENIC SOURCES
o Sour gas processing
o Oil sands production
o Coal combustion, ore refining
o Chemical manufacturing
o Fossil fuel processing and burning.
o Vehicles can also contribute to high local ambient concentration sulfur dioxide.
o Industrial boilers and nonferrous metal smelters.