Method of integrating a blast furnace with an air gas separation unit

Abstract

The invention relates to a method of integrating a plurality of blast furnaces with a plurality of air gas separation units, in which the replacement blower available on the blast furnace site is used to feed compressed air into an air gas separation unit making it possible to enrich the blast-furnace blast with oxygen, this unit being stopped when one of the blowers of the blast furnaces has to be replaced with the blower used by the air gas separation unit.

1 - 9 . (canceled) 
   
   
       10 . A method of integrating n (≧1) blast furnaces with at least one air gas separation unit, in which the n blast furnaces and the air gas separation unit producing oxygen are fed with air by at least n+1 compressors, since each blast furnace is fed by at least one compressor from the at least n+1 compressors available, at least one of the compressors that are not feeding a blast furnace (“second compressor”) is used to feed the air gas separation unit, and as soon as one of the compressors (“first compressor”) feeding a blast furnace produces air at a flow rate below a predetermined flow rate Dmin, said first compressor is disconnected from said blast furnace and the second compressor is connected to said blast furnace and preferably disconnected from the air gas separation unit. 
   
   
       11 . The method of  claim 10 , wherein a supplementary compressor delivers compressed air and/or the overpressure to the air gas separation unit. 
   
   
       12 . The method of  claim 10 , wherein the blast furnaces are fed with oxygen by the air gas separation unit. 
   
   
       13 . The method of  claim 10 , wherein at least some of the oxygen produced by the air gas separation unit is used in at least one converter. 
   
   
       14 . The method of  claim 10 , wherein the air gas separation unit produces oxygen with an oxygen purity of greater than 90 vol %. 
   
   
       15 . The method of  claim 14 , wherein the air gas separation unit produces oxygen with an oxygen purity of greater than 95 vol %. 
   
   
       15 . The method of  claim 14 , wherein the air gas separation unit produces oxygen with an oxygen purity of greater than 95 vol %. 
   
   
       16 . The method of  claim 10 , wherein the air gas separation unit has two operating modes, namely a regular operating mode producing oxygen with a purity of greater than 90 vol % and a degraded operating mode producing oxygen with a purity of 90 vol % or less. 
   
   
       17 . The method of  claim 10 , wherein the air gas separation unit has two operating modes, namely a regular operating mode producing oxygen with a purity of greater than 95 vol % and a degraded operating mode producing oxygen with a purity of 95 vol % or less. 
   
   
       18 . The method of  claim 10 , wherein the air gas separation unit has two operating modes, namely a regular operating mode producing a first oxygen flow and a degraded operating mode producing an oxygen flow smaller than the first oxygen flow. 
   
   
       19 . An installation for implementing the method as claimed in  claim 10 , wherein the installation comprises n (≧1) blast furnaces, an air gas separation unit and at least n+1 compressors, each blast furnace being connected to at least one compressor via air feed lines, the installation further including lines for connecting one of the compressors, called second compressor, either to the air feed line for at least one of the blast furnaces or to the air gas separation unit, or to both. 
   
   
       20 . The method of  claim 11 , wherein the blast furnaces are fed with oxygen by the air gas separation unit. 
   
   
       21 . The method of  claim 20 , wherein at least some of the oxygen produced by the air gas separation unit is used in at least one converter. 
   
   
       22 . The method of  claim 21 , wherein the air gas separation unit produces oxygen with an oxygen purity of greater than 90 vol %. 
   
   
       23 . The method of  claim 21 , wherein the air gas separation unit produces oxygen with an oxygen purity of greater than 95 vol %. 
   
   
       24 . The method of  claim 21 , wherein the air gas separation unit has two operating modes, namely a regular operating mode producing oxygen with a purity of greater than 90 vol % and a degraded operating mode producing oxygen with a purity of 90 vol % or less. 
   
   
       25 . The method of  claim 21 , wherein the air gas separation unit has two operating modes, namely a regular operating mode producing a first oxygen flow and a degraded operating mode producing an oxygen flow smaller than the first oxygen flow. 
   
   
       26 . The method of  claim 23 , wherein the air gas separation unit has two operating modes, namely a regular operating mode producing a first oxygen flow and a degraded operating mode producing an oxygen flow smaller than the first oxygen flow. 
   
   
       27 . The method of  claim 24 , wherein the air gas separation unit has two operating modes, namely a regular operating mode producing a first oxygen flow and a degraded operating mode producing an oxygen flow smaller than the first oxygen flow. 
   
   
       28 . An installation for implementing the method as claimed in  claim 21 , wherein the installation comprises n (≧1) blast furnaces, an air gas separation unit and at least n+1 compressors, each blast furnace being connected to at least one compressor via air feed lines, the installation further including lines for connecting one of the compressors, called second compressor, either to the air feed line for at least one of the blast furnaces or to the air gas separation unit, or to both. 
   
   
       29 . An installation for implementing the method as claimed in  claim 23 , wherein the installation comprises n (≧1) blast furnaces, an air gas separation unit and at least n+1 compressors, each blast furnace being connected to at least one compressor via air feed lines, the installation further including lines for connecting one of the compressors, called second compressor, either to the air feed line for at least one of the blast furnaces or to the air gas separation unit, or to both. 
   
   
       30 . An installation for implementing the method as claimed in  claim 24 , wherein the installation comprises n (≧1) blast furnaces, an air gas separation unit and at least n+1 compressors, each blast furnace being connected to at least one compressor via air feed lines, the installation further including lines for connecting one of the compressors, called second compressor, either to the air feed line for at least one of the blast furnaces or to the air gas separation unit, or to both.