The dryer has drying sections (2) arranged one above the other and comprising a horizontal air channel arrangement. Side walls of the sections are arranged parallel to the air channel arrangement and inclined around an inclination angle (theta) between 5 and 45 degrees. The air channel arrangement has supply air channels (3) that are arranged one above other such that middle points of the air channels pass through a diagonal that corresponds to the inclination angle, where the drying sections are provided with complete air channels.