Method for producing a metal melt and corresponding multifunction lance
AssigneeVoest-Alpine Industrieanlagenbau GmbH
InventorErnst Fritz
Life of this patent
Estimating the term…
Abstract
The invention relates to a method for producing a metal melt in a metallurgical vessel, in particular an iron or steel melt, feed substances which contain metals and/or metal oxides, being charged in solid and, if appropriate, molten form into the metallurgical vessel, the main part of the energy necessary for the melting and, if appropriate, finish-reduction of the feed substances being applied electrically and/or by the combustion and/or gasification of carbon-containing materials. The invention relates, further, to multi-functional lances for use in a method according to the invention.
Claims47
A method for producing a metal melt in a metallurgical vessel, wherein feed substances which contain metals and/or metal oxides are charged in solid and/or molten form into the metallurgical vessel, the main part of the energy necessary for the melting and/or the finish-reduction of the feed substances is applied electrically and/or by the combustion and/or the gasification of carbon-containing materials,
- comprising the steps of:
- A) supplying additional energy to the feed substances by the blowing-in, by means of one or more multi-functional lances, and the combustion of gaseous and/or liquid carbon-containing materials and oxygen-containing gas;
- B) cutting and partially melting the solid feed substances by the intensified blowing-in of oxygen-containing gas by means of the multi-functional lance;
- C) refining the melted feed substances by the intensified blowing-in of oxygen-containing gas by means of the multi-functional lance;
- D) alloying carbon and/or supplying additional energy to the feed substances by the blowing-in and/or burning of fine-grained and/or dust or powder-type solid carbon-containing materials by means of the multi-functional lance;
- E) after-burning, in a post-combustion step, waste gases from the metallurgical vessel by the blowing-in of oxygen-containing gas into the waste-gas space of the metallurgical vessel by means of the multi-functional lance, wherein the jet of the oxygen-containing gas from each multi-functional lance is skewed to the central longitudinal axis of the respective multi-functional lance and is set in a helical rotational movement;
- F) supplying necessary substances to the feed substances by the blowing-in of fine-grained, dust, and/or powder-type solid aggregates and/or alloying agents by means of the multi-functional lance, in order to achieve a desired composition of the metal melt;
- wherein a performance of each step A) through F) depends on the composition of the feed substances and on the desired composition of the metal melt, selectively in any desired combination, in succession and/or in reverse order and/or simultaneously and/or omitting the step D) and/or the step F).
A multi-functional lance for use in a method for producing a metal melt in a metallurgical vessel, comprising:
- a plurality of tubes which surround one another and are concentric to a central longitudinal axis and a common end of which forms the head of the multi-functional lance;
- a first tube for forming a supply duct for solid, fine-grained, dust, and/or powder-type substances;
- a second tube surrounding the first tube so as to form a first annular gap for the supply of an oxygen-containing gas, wherein the mouth part of the second tube being designed as a Laval nozzle;
- a third tube surrounding the second tube so as to form a second annular gap for the supply of gaseous and/or liquid fuel;
- a fourth tube surrounding the third tube so as to form a third annular gap for the supply of an oxygen-containing gas;
- a fifth tube surrounding the fourth tube so as to form a fourth annular gap for the supply of an oxygen-containing gas, wherein the fourth annular gap terminates on the mouth side, so as to form a plurality of outflow ducts, wherein the centre axis of each outflow duct is skew to the central longitudinal axis so that the oxygen-containing gas is set in a helical rotational movement.
A multi-functional lance for use in a method for producing a metal melt in a metallurgical vessel comprising:
- a plurality of tubes which surround one another and are concentric to a central longitudinal axis and a common end of which forms the head of the multi-functional lance;
- a first tube for forming a supply duct for liquids or oxygen-containing gas;
- a second tube surrounding the first tube so as to form a first annular gap for the supply of an oxygen-containing gas, wherein the mouth part of the second tube is a Laval nozzle;
- a third tube surrounding the second tube so as to form a second annular gap for the supply of gaseous and/or liquid fuel;
- a fourth tube surrounding the third tube so as to form a third annular gap for the supply of an oxygen-containing gas;
- a fifth tube surrounding the fourth tube so as to form a fourth annular gap for the supply of cooling water, wherein the fourth annular gap is closed on the mouth side;
- a sixth tube surrounding the fifth tube so as to form a fifth annular gap for the supply of oxygen-containing gas, wherein the fifth annular gap terminates on the mouth side, so as to form a plurality of outflow ducts, and the centre axis of each outflow duct is skew to the central longitudinal axis, so that the oxygen-containing gas is set in a helical rotational movement;
- a seventh tube surrounding the sixth tube so as to form a sixth annular gap for drawing off cooling water, wherein the sixth annular gap is closed on the mouth side, and the fourth annular gap is connected to the sixth annular gap, in the region of the head of the multi-functional lance, by means of bores which do not cross the outflow ducts;
- one to nine nozzle tubes of wear-resistant design for the supply of solid, fine-grained, dust, and/or powder-type substances, wherein the nozzle tubes arranged within the fifth annular gap and the centre axis of each nozzle tube are parallel to the longitudinal axis, and the nozzle tubes pierce the head of the multi-functional lance, without crossing bores or outflow ducts.
Dependencies are inferred from the claim text.