Device for cooling the opening of a rotary kiln by means of cool air-blowing

A device (100) for cooling the opening of a rotary kiln (1) by means of cool air-blowing, said kiln comprising a metal cylinder (3) lined internally with a refractory material (73), said cylinder (3) being rotatably mounted relative to the frame of the kiln, into which materials are intended to be inserted and fired,

• said device (100) for cooling comprising:
• said cylinder (3) of said rotary kiln and an end part (4) of the metal cylinder, covered with a refractory material (74), secured to said cylinder (3), intended to protect the end of the cylinder (3) of the kiln from high temperatures,
• two concentric metal casings (5, 6), known as the inner casing (5) and outer casing (6), said two casings (5, 6) surrounding said cylinder (3) of the kiln (1) and constituting two annular channels (50, 60) between on the one hand, said cylinder (3) and said inner casing (5), known as the first channel (50), and on the other hand, between said inner casing (5) and said outer casing (6), known as the second channel (60),
• ventilation means that allow cool air to flow through said annular channels (50, 60),
• in such a way as to allow the flow of air in said first channel (50) to the end part (4), then the flow of air in the opposite direction in said second channel (60), before the escaping of the air via an exhaust opening of said second channel (60),
• an annular distribution chamber (8), surrounding said cylinder (3) and secured to said cylinder (3) of the kiln, supplying said first channel (50) with air,
• said ventilation means comprising at least one fan (9) and an electric motor actuating said at least one fan (9), said ventilation means being borne on the metal cylinder (3) of the kiln, rotatably mounted therewith, supplying said distribution chamber (8) in an air-tight manner,
• rotating electrical connectors (10, 11), comprising annular rings (10) surrounding said cylinder (3) of the kiln, and contacts (11), able to slide or roll on the annular rings (10) during the rotation of the kiln in order to allow electricity to be supplied to the electric motor(s) of said ventilation means, and
• wherein,
• the annular rings (10) are placed on the distribution chamber (8), on the most outer wall of said distribution chamber (8) relative to the cylinder (3) of the kiln,
• an annular screen (12) is arranged between said exhaust opening of the second channel (60) and said rotating electrical connectors (10, 11), and
• the cool air drawn by said at least one fan (9) flows in a casing surrounding the electric motor of said fan (9) before it enters said fan (9).