Nitrous oxide its concentration has increased 15% since 1750, control of nitrous oxide is considered part of efforts to curb greenhouse gas emissions. A 2008 study by Nobel Laureate Paul Crutzen suggests that the amount of nitrous oxide release attributable to agricultural nitrate fertilizers has been seriously underestimated, most of which presumably, would come under soil and oceanic release in the Environmental Protection Agency data. Nitrous oxide also has been implicated in thinning of the ozone layer. A new study suggests that emission currently is the single most important ozone-depleting substance (ODS) emission and is expected to remain the largest throughout the
Sulfur dioxide and 2002. This improvement resulted in part from flue-gas desulfurization, a technology that enables SO to be chemically bound in power plants burning sulfur-containing coal or oil. In particular, calcium oxide (lime) reacts with sulfur dioxide to form calcium sulfite: Aerobic oxidation of the CaSO gives CaSO, anhydrite. Most gypsum sold in Europe comes from flue-gas desulfurization. Sulfur can be removed from coal during burning by using limestone as a bed material in fluidized bed combustion. Sulfur can also be removed from fuels before burning, preventing formation of SO when the fuel is burnt. The Claus process is used in