A process for manufacturing self-reducing pellets/briquettes from bag house dust mixed with carbon to be used in steelmaking furnaces

Abstract

Bag house dust is combined with a carbon source and shaped into pellets or briquettes and used to recycle valuable metals present in the bag house dust.

1 . A solid composition adapted for use as a feed stock in steel making furnaces comprising;
 (i) a baghouse dust comprising iron oxide and at least 1% zinc by weight; and   (ii) a carbon source;   wherein said solid composition is in the form of a briquette or pellet   
     
     
         2 . The solid composition of  claim 1 , wherein the product does not comprise either or both of ferrous chloride and ferrous sulfate amount that alters the properties of the composition as a feed stock in steel making furnaces. 
     
     
         3 . The solid composition of  claim 1 , wherein the carbon source comprises greater than 50% carbon by weight. 
     
     
         4 . The solid composition of  claim 1 , wherein the carbon source comprises at least one member selected from the group consisting of anthracite, graphite, coal, coke, petcoke, coal tar pitch, tar, tar, molasses and decanter sludge. 
     
     
         5 . The solid composition of  claim 1 , wherein the iron oxide is iron (II) oxide (FeO), iron (III) oxide (Fe 2 O 3 ), iron (II,III) oxide (Fe 3 O 4 , Fe 5 O 6 , Fe 5 O 7 ), or mixtures thereof. 
     
     
         6 . The solid composition of  claim 1 , wherein the zinc is zinc oxide (ZnO), or any other zinc containing oxide, zinc ferrite, or mixtures thereof. 
     
     
         7 . The solid composition of  claim 1 , further comprising from greater than 0% up to 15% by weight of an additive. 
     
     
         8 . The solid composition of  claim 7 , wherein the additive comprises at least one member selected from the group consisting of lime, calcium chloride, silica, limestone, clay, iron grindings, steel grindings, iron borings, steel borings, iron turnings and steel turnings. 
     
     
         9 . The solid composition of  claim 1 , wherein the baghouse dust comprises greater than 30% iron oxide by weight. 
     
     
         10 . The solid composition of  claim 1 , wherein the baghouse dust comprises 30% to 70% iron oxide by weight. 
     
     
         11 . A briquette or pellet adapted for use as a recycled feed stock in electric arc and/or basic oxygen furnaces, the briquette or pellet comprising;
 (i) 60 to 90% by weight of a bag house dust comprising iron oxide and zinc, wherein the iron oxide comprises 30 to 70% by weight of the bag house dust;   (ii) 3 to 20% by weight of a carbon source; and   (iii) 0 to 15% by weight additive.   
     
     
         12 . The briquette or pellet of  claim 11 , wherein the product does not comprise either or both of ferrous chloride and ferrous sulfate. 
     
     
         13 . The briquette or pellet of  claim 11 , wherein the carbon source comprises greater than 50% carbon by weight. 
     
     
         14 . The briquette or pellet of  claim 11 , wherein the carbon source comprises at least one member selected from the group consisting of anthracite, graphite, coal, coke, petcoke, coal tar pitch, tar, tar, molasses and decanter sludge. 
     
     
         15 . The briquette or pellet of  claim 11 , wherein the additive comprises at least one member selected from the group consisting of lime, calcium chloride, silica, limestone, clay, iron grindings, steel grindings, iron borings, steel borings, iron turnings and steel turnings. 
     
     
         16 . The briquette or pellet of  claim 11 , wherein the iron oxide comprises at least one member selected from the group consisting of iron (II) oxide (FeO), iron (III) oxide (Fe 2 O 3 ), and iron (II,III) oxide (Fe 3 O 4 , Fe 5 O 6 , Fe 5 O 7 ). 
     
     
         17 . The briquette or pellet of  claim 11 , wherein the zinc is zinc oxide (ZnO), or any other zinc-containing oxide, zinc ferrite, or mixtures thereof. 
     
     
         18 . The briquette or pellet of  claim 13 , wherein the additive comprises at least one member selected from the group consisting of lime, calcium chloride, silica, limestone, clay, iron grindings, steel grindings, iron borings, steel borings, iron turnings and steel turnings. 
     
     
         19 . The briquette or pellet of  claim 13 , wherein the iron oxide comprises at least one member selected from the group consisting of iron (II) oxide (FeO), iron (III) oxide (Fe 2 O 3 ), and iron (II,III) oxide (Fe 3 O 4 , Fe 5 O 6 , Fe 5 O 7 ). 
     
     
         20 . The briquette or pellet of  claim 13 , wherein the zinc is zinc oxide (ZnO), or any other zinc-containing oxide, zinc ferrite, or mixtures thereof.