Gas desulphurization System

Enfil has gas Desulphurization Systems of wet, semi-dry and dry way:

Wet Process with Limestone (LSFO - Limestone Slurry Forced Oxidation)

It?s the most used process in large thermal power plants. The flue gas reacts with the limestone ("slurry") to form calcium sulphite, later oxidated to sulphate by means of aeration. The reacted slurry is dewatered and the solid by-product (gypsum) can be used at the civil construction, among others (for example, wallboards).

SOx Removal efficiency: up to 98%

Wet process with sea water

Uses sea water as reagent for the absorption of SOx. The natural alkalinity of the water is responsible for the elimination of the SOx of the gas phase. As in the LSFO process the sulphite generated in the absorption reaction is oxidated to sulphate through aeration. The great advantages of this process are the absence of by-products and the low cost of the reagent (seawater). The seawater after scrubbing is discharged again to the sea.

SOx Removal efficiency: up to 98%

Semi-dry Process with Lime

In this process the SOx is removed from the flue gas by a lime slurry (milk of lime) finely atomized into the gas stream. In the ?reactor? SOx is absorbed while all the water in the droplets is vaporized by the hot flue gas. After the absorber, the gases go to a Bag Filter or Electrostatic Precipitator where the dry by-product ("spent lime" ) is collected. The by product has no commercial value.

SOx Removal efficiency: up to 92%

Dry Process with hydrated Lime (CDS - Circulating Dry Scrubber)

Pulverized hydrated lime is injected into the absorber where it reacts with the SOx of the gas phase. The gases are sent to a Bag Filter or Electrostatic Precipitator. Part of the material collected is recirculated and part is discarded.

SOx Removal efficiency: up to 95%