LANCE FOR IMMERSION IN A PYROMETALLURGICAL BATH AND METHOD INVOLVING THE LANCE

A method for submerged injection of materials into a liquid pyrometallurgical bath by means of a lance, characterised in that a first gas consisting of or containing oxygen is conveyed to said bath along a first path within the lance, a combustible fluid is conveyed to said bath along another path within the lance, and a further gas consisting of or containing oxygen is conveyed to said bath along a further path within the lance, the first path being arranged so that the first gas acts as a coolant for the lance. A lance for submerged injection of materials into a liquid pyrometallurgical bath, comprising an outer end portion to be submersed in the bath, an outer lengthwise extending tubular member, an inner lengthwise extending tubular member positionned within the outer tubular member, an annular duct being thereby defined between the outer and inner tubular members for conveying a gas consisting of or containing oxygen to an open outer end thereof, a conduit positioned within and extending lengthwise of the inner tubular member for conveying further gas consisting of or containing oxygen to the outer end portion of the lance, a lengthwise passage being thereby defined between the inner tubular member and the conduit for conveying combustible fluid to the outer end portion of the lance, at least one port providing communication between the passage and the annular duct and at least one exit passageway providing communication between the conduit and the annular duct at a location downstream of the port or ports, for directing the further gas flowing from the conduit into the annular duct. On décrit un procédé d'injection submergée de matériaux dans un bain pyrométallurgique à l'aide d'une lance. Un premier gaz, l'oxygène ou un gaz contenant de l'oxygène, est introduit dans ledit bain par une première canalisation de la lance. Un fluide combustible est envoyé dans ledit bain par une autre canalisation de la lance, et un autre gaz, l'oxygène ou un gaz contenant de l'oxygène, est introduit dans ledit bain par une autre canalisation de la lance. La première canalisation est disposée de telle manière que le premier gaz agisse comme agent de refroidissement de la lance. On décrit aussi une lance adaptée à l'injection submergée de matériaux dans un bain pyrométallurgique, comportant une partie extérieure extrême à immerger dans le bain; un élément tubulaire longitudinal extérieur; et un élément tubulaire longitudinal intérieur agencé dans l'élément tubulaire exté