A multiple product belt drier having a first air permeable conveyor belt on which the materials to be dried are poured to form a first drying path; at least a second air permeable conveyor belt to assure at least a second drying path for drying the materials after the first one; an air blowing mechanism; an air heating mechanism for heating the blown air to dry the materials, and a drying air distribution circuit for distributing the drying air towards the materials and the belts; the drying air circuit being provided so that the drying air circulates downwards through the materials to be dried and the belts, and an air reheating mechanism is provided between the two paths to reheat the air which has passed through the layer of materials on the first belt, before it passes through the layer of materials on the second belt.