2. Notion of value chain

The polluted air to be treated is a complex mixture made up of a wide range of products of different sizes, including particles, dust, organic and inorganic molecules, and water vapor in varying concentrations. As with water treatment or purification, this requires the implementation of treatment processes [1][24] . These successions of unit operations are designed to optimize the elimination of each class of product, and thus the overall purification of the polluted emission. They also include treatment of the by-products generated.