Melting/refining furnace for cold iron sources, and melting/refining furnace operation method

Patent metadata

Field	Value
Publication number	US-2023349016-A1
Application number	US-202117921249-A
Country	US
Kind code	A1
Filing date	Apr 14, 2021
Priority date	Apr 27, 2020
Publication date	Nov 2, 2023
Grant date	—

Abstract

The object of the present invention is to provide a melting/refining furnace for cold iron sources and an operation method for a melting/refining furnace that can increase the heating efficiency of the raw material without causing oxidation of the raw material, reduce the amount of power consumption required for melting the raw material, shorten the melting and refining time, improve the productivity, and reduce costs, and the present invention provides a melting/refining furnace including: one or more through-holes ( 21 ) provided to penetrate a furnace wall ( 2 A) of an electric furnace ( 2 ); and an oxygen burner-lance ( 3 ) provided in the through-hole ( 21 ), wherein the oxygen burner-lance ( 3 ) includes at least one combustion-supporting gas supply pipe ( 31 ) and at least one fuel gas supply pipe ( 32 ) which have an opening communicating with an inside of the electric furnace ( 2 ), and wherein a high-temperature gas generator ( 10 ) is provided in any one or more of the combustion-supporting gas supply pipes ( 31 ).

First claim

1 . A melting/refining furnace including an oxygen burner-lance for ejecting a combustion-supporting gas containing oxygen and a fuel gas toward cold iron sources in the furnace,
wherein the melting/refining furnace includes: one or more through-holes provided to penetrate a furnace wall; and an oxygen burner-lance provided in the through-hole, wherein the oxygen burner-lance includes at least one combustion-supporting gas supply pipe having an opening communicating with an inside of the furnace and at least one fuel gas supply pipe having an opening communicating with an inside of the furnace, and wherein a high-temperature gas generator is provided in any one or more of the combustion-supporting gas supply pipes.

2 . The melting/refining furnace according to claim 1 ,
wherein the high-temperature gas generator includes: a burner in which a high-temperature combustion-supporting gas is produced by mixing a high-temperature gas and a gas to be heated, the high-temperature combustion-supporting gas produced is supplied to the oxygen burner-lance as a combustion-supporting gas, and a high temperature gas is produced; and a pre-heating chamber which is provided downstream of the burner in a flow direction of a gas ejected from the burner and mixes the high-temperature gas and the gas to be heated, wherein the burner includes: a combustion chamber in which a flame is produced by the fuel gas and the combustion-supporting gas; a fuel flow path that supplies the fuel gas to the combustion chamber; a combustion-supporting gas flow path that supplies the combustion-supporting gas to the combustion chamber; and a gas to be heated flow path which communicates with the pre-heating chamber and supplies the gas to be heated toward the pre-heating chamber.

3 . The melting/refining furnace according to claim 2 ,
wherein the high-temperature gas generator further includes a cooling jacket which cools the burner or both the burner and the pre-heating chamber.

4 . The melting/refining furnace according to claim 2 ,
wherein the melting/refining furnace further includes: a thermometer that measures the temperature in the furnace; and a flow control unit that is electrically connected to the thermometer, and based on the temperature in the furnace measured by the thermometer, controls an amount of the combustion-supporting gas and the fuel gas supplied to the oxygen burner-lance, and an amount of the fuel gas, the combustion-supporting gas, and the gas to be heated to the high-temperature gas generator.

5 . The melting/refining furnace according to claim 2 ,
wherein the melting/refining furnace further includes: a discharge passage which discharges a discharged gas from inside of the furnace; a discharged gas analyzer which is provided in the discharge passage for discharged gas and measures at least one of a concentration of components contained in the discharged gas and the flow rate of the discharged gas; a discharged gas thermometer which is provided in the discharge passage for discharged gas downstream of the discharged gas analyzer in a flow direction of the discharged gas and measures the temperature of the discharged gas; and a flow rate control unit which receives a measured value of the temperature of the discharged gas from the discharged gas thermometer, and a measured value of the concentration of components and the flow rate of the discharged gas from the discharged gas analyzer, analyzes these measured values, and controls an amount of the combustion-supporting gas and the fuel gas supplied to the oxygen burner-lance and an amount of the fuel gas, the combustion-supporting gas, and the gas to be heated to the high-temperature gas generator.

6 . The melting/refining furnace according to claim 1 ,
wherein the combustion-supporting gas is oxygen gas or oxygen-enriched air.

7 . The melting/refining furnace according to claim 2 ,
wherein the gas to be heated supplied to the high-temperature gas generator is oxygen gas.

8 . An operation method of a melting/refining furnace in which a combustion-supporting gas containing oxygen and a fuel gas are ejected toward cold iron sources in the furnace using an oxygen burner-lance, and the cold iron sources are melted and refined,
wherein the operation method includes: a step in which a combustion-supporting gas is heated to a high temperature by a high-temperature gas generator provided in a combustion-supporting gas supply pipe in an oxygen burner-lance to obtain a high-temperature combustion-supporting gas; a step in which the high-temperature combustion-supporting gas is ejected toward the cold iron sources in the furnace as a combustion-supporting gas; and a step in which, based on a measured temperature in the furnace, an amount of the combustion-supporting gas and the fuel gas supplied to the oxygen burner-lance is controlled, and combustion of the oxygen burner-lance is started and stopped.

9 . An operation method of a melting/refining furnace in which a combustion-supporting gas containing oxygen and a fuel gas are ejected toward cold iron sources in the furnace using an oxygen burner-lance, and the cold iron sources are melted and refined,
wherein the operation method includes: a step in which a combustion-supporting gas is heated to a high temperature by a high-temperature gas generator provided in a combustion-supporting gas supply pipe of an oxygen burner-lance to obtain a high-temperature combustion-supporting gas; a step in which the high-temperature combustion-supporting gas is ejected toward the cold iron sources in the furnace as a combustion-supporting gas; and a step in which, based on measured values of a temperature of a discharged gas discharged from inside of the furnace, the concentration of components contained in the discharged gas, and the flow rate of the discharged gas, an amount of the combustion-supporting gas and the fuel gas supplied to the oxygen burner-lance, and an amount of the fuel gas, the combustion-supporting gas and a gas to be heated to the high-temperature gas generator are controlled, and the combustion of the oxygen burner-lance is started and stopped.

Assignees

• Taiyo Nippon Sanso Corp

Inventors

• Yamaguchi Masashi
• Yamamoto Yasuyuki
• Hagihara Yoshiyuki

Classifications

• F23N5/022

  using electronic means (F23N5/04 - F23N5/14 take precedence) · CPC title

• F27D21/00

  Arrangement of monitoring devices; Arrangement of safety devices · CPC title

• F27D99/0033

  using burners · CPC title

• F27D19/00

  Arrangements of controlling devices · CPC title

• F27D7/02

  Supplying steam, vapour, gases or liquids · CPC title