Abstract: The industrial oven according to the invention has a rotary pipe and a fixed material supply device which is connected in the region of a front-face opening of the rotary pipe, there being provided between the rotary pipe and the material supply device a sealing arrangement which comprises a gas seal which is delimited from the operating chamber of the rotary pipe acted upon with material by at least a first gap between the rotary pipe and the material supply device. The sealing arrangement further has an annular chamber which is provided between the first gap and the gas seal and which has a discharge opening which is connected to the operating chamber. A lifting device is further provided in the annular chamber in order to lift out of the operating chamber material which has become introduced into the annular chamber through the first gap and to convey it back to the operating chamber through the discharge opening.

Abstract: The industrial oven according to the invention has a rotary pipe and a fixed material supply device which is connected in the region of a front-face opening of the rotary pipe, there being provided between the rotary pipe and the material supply device a sealing arrangement which comprises a gas seal which is delimited from the operating chamber of the rotary pipe acted upon with material by at least a first gap between the rotary pipe and the material supply device. The sealing arrangement further has an annular chamber which is provided between the first gap and the gas seal and which has a discharge opening which is connected to the operating chamber. A lifting device is further provided in the annular chamber in order to lift out of the operating chamber material which has become introduced into the annular chamber through the first gap and to convey it back to the operating chamber through the discharge opening.