The method comprises: making an exterior air stream to enter into a grain dryer (1) introducing a flow of grains by gravity into the grain dryer passing the air stream through the grain flow in a direction perpendicular to a direction of the flow of grain filtering the air stream when it is passed through the grains so as to retain particles present in the air stream heating the filtered flow and then directing to an upstream of the flow of grain such that the filtered flow recrosses the grains and blowing the particles from the filtered flow. The method comprises: making an exterior air stream to enter into a grain dryer (1) introducing a flow of grains by gravity into the grain dryer passing the air stream through the grain flow in a direction perpendicular to a direction of the flow of grain filtering the air stream when it is passed through the grains so as to retain particles present in the air stream heating the filtered flow and then directing to an upstream of the flow of grain such that the filtered flow recrosses the grains and blowing the particles from the filtered flow. The air flow is again filtered, after it is recrossed over the grain flow, where the particles resulting from the second filtration is then blown. An independent claim is included for a device for filtering an air stream in a grain dryer.La présente invention est relative à un procédé de filtration dun flux dair dans un séchoir à grains permettant le recyclage de lair, dans lequel :- on fait entrer un flux dair extérieur dans ledit séchoir à grains (1) - on déverse par gravité un flux de grains dans ledit séchoir à grains (1) - on fait passer ledit flux dair au travers du flux de grains selon une direction sensiblement perpendiculaire à la direction du flux de grains - on filtre le flux dair, une fois que celui-ci est passé au travers des grains, de manière à retenir les particules présentes dans le flux dair- on réchauffe le flux filtré et on le dirige en amont du flux de grains de mani
