Abstract: An industrial plant for gas treatment, comprising a gas treatment unit, the gas treatment unit comprising a first, a second and a third compartments extending vertically; the first compartment comprising a gas inlet the second compartment comprising a first gas outlet; the gas treatment unit also comprising a first and a second porous structures in the first and in the second compartments, the first porous structure being situated higher than the gas inlet, the second porous structure being situated lower than the first gas outlet. The gas treatment unit also comprises: a first opening, situated between the first and third compartments, higher than the first porous structure; and a second opening, situated between the third and second compartments, lower than the second porous structure.