Dropping sulfur, an essential process is to get rid of lower organisms from fuel, flue gases, industrial emissions of all kinds. With its main purpose being to combat air pollution it has brought down the amount of sulfur dioxide that is discharged into the atmosphere, a major cause of both acid rain and lung troubles. The technology of de sulfurization, using diverse approaches such as wet scrubbing, dry sorbent injection and catalytic reduction to absorb and turn sulfur dioxides into harmless compounds. These systems are extremely efficient and are usually incorporated into power plants, refineries or other large installations where high-sulfur fuels are burned. Applications are numerous, ranging from conformity to environmental rules in order ot improve air quality and public health.