Wet-process

In wet flue gas treatment processes (wet scrubbers) designed for acid gas removal, the flue gas is cooled down via water evaporation below acid dew point (50 – 70 °C). Flue gas then passes through a scrubbing liquid. This can be water or an alkaline solution. The acidic gas components are dissolved in the scrubbing liquid and neutralized through a reaction with the alkaline sorbent. Depending on their water solubility, reaction products either remain dissolved in the scrubber liquid (mainly calcium chlorides) or they precipitate as solids (calcium sulphite CaSO₃ and calcium sulphate CaSO₄). 

Wet scrubbers are very effective for acid gas removal. They offer very high (> 99%) removal rates for HCl, HF and SO₂, with the lowest possible sorbent consumption. They also require a high capital investment, as well as effluent treatment before final discharge. The ability to use economically-favourable limestone (CaCO₃) means this process widely used, especially for larger units where constant quality and security of supply are critical. 

With its extensive network of plants located on high-purity limestone deposits and its expertise in supply chain management, Lhoist is the ideal partner for this type of FGT process. Because wet scrubbers do not remove SO₃ efficiently, combined processes with DSI for SO₃ reduction may be required. 

We provide Sorbacal^® C, limestone (CaCO₃) sorbents in a variety of particle size distributions tailored to your wet scrubbing process equipment. The Sorbacal^® C sorbents are of high purity and high whiteness, thus maximizing the value of the gypsum byproduct.

• Sorbacal^® Q
• Mag-on-demand
• Sorbacal^® SL
• Sorbacal^® Micro