Abstract: The present invention relates to a device for processing a flow of solid products with a counter-current flow of liquid to achieve for example a heat exchange comprising a drum rotating about its longitudinal axis, an endless screw or helix arranged within the drum and solid in rotation therewith, and defining sections, in each section is arranged a vane element which is secured to the face of the drum between two adjacent turns of the helix to impede progression of the products in the drum, and perforations or grids provided in the portion of the helix turn which is located upstream of the vane with respect to the direction of progression of the products in the drum, and above and upstream of the face of the vane, this invention being used more particularly in the food industry.