Abstract: A bifurcated fan (1) which draws in atmospheric air through air/liquid contact blocks of plastic grids which are sprayed with the liquid to be treated. The blocks change position in order to be sprayed on both front surfaces alternatively and thus remain clean. The liquid evaporates in the contact blocks and the concentrate is dehydrated in a secondary laminar evaporation base. The arrangement into converging sectors provides a geometry with minimal aerodynamic losses in a liquid with organic matter. The device includes a central tank which facilitates an aerobic biopurification process aided by the oxygenation in the contact blocks. Thermal exchanges may be included at the air inlet, using residual energy, particularly from thermal engines to which it provides refrigeration and cleaning of exhaust gases.