Carmeuse has developed a magnesium-enhanced-lime-based wet flue gas desufurization (FGD) process for control of sulfur dioxide emissions. This process is been continuously improved by Carmeuse's team since 1977. The magnesium-enhanced Thiosorbic^® wet lime process utilizes 2.25 million metric tons of lime annually. 

This process is the first lime consumer for FGD application in the USA as it represent more than 70% of the lime volume used in FGD as shown on the below table.

The improved version of this process allows ultra-high sulfur removal efficiency (above 99%) and produces of course valuable by-products: gypsum and magnesium hydroxide. The gypsum produced by the new process is sold for manufacture of building materials such as wallboard and plaster. The process can also produce magnesium hydroxide as a byproduct, which has been used successfully for control of sulfuric acid emissions and to eliminate plume opacity.

The MEL process looks like more complex but this allow at competitive price (operating and investment costs) to remove ultra-high removal efficiency. Like all wet process, the MEL technology is based on the reaction bewteen a suspension (mag-lime slurry in this case) and the flue gases. Scrubber desing intend to promote maximum gas-liquid surface area and residence time in order to perform high removal efficiencies (up to 99%).

The sulfur containing slurry is then oxidized in a separate vessel to produce solid FGD-gypsum which is removed from the slurry by physical separation (filter, decanter...).

For more information on this technology, see technical papers & report section.

A complete report on this technology is available here >>> 

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