Systems and methods for carbothermically producing aluminum

Abstract

Systems and associated methods for carbothermically producing aluminum are provided, the systems generally including a reactor having a depth such that when the reactor contains molten liquid hydrostatic pressure of the molten liquid is at least about 0.5 atm as measured proximal the bottom of the reactor. A plurality of horizontally disposed electrodes, which may be offset from one another in a vertical and/or horizontal direction, may also be used in accordance with the system to provide selective heating gradients within the molten liquid.

1 . A carbothermic aluminum production system comprising:
 a reactor comprising sidewalls, a top and a bottom defining a reaction chamber;   a vapor recovery unit fluidly interconnectable to said reaction chamber; and   a plurality of horizontally disposed electrodes interconnected to said sidewalls of said reactor;   
     wherein said sidewalls of said reactor extend from said bottom of said reactor to a height such that when said reactor contains molten liquid the hydrostatic pressure of said molten liquid is at least about 0.5 atm as measured proximal said bottom of said reactor. 
   
   
       2 . The carbothermic aluminum production system of  claim 1 , wherein said plurality of horizontally disposed electrodes includes a first set of electrodes and a second set of electrodes, said first said of electrodes being disposed above said second set of electrodes. 
   
   
       3 . The carbothermic aluminum production system of  claim 2 , wherein said first set of electrodes are operable to heat aluminum slag to a first temperature and wherein said second set of electrodes are operable to heat aluminum slag to a second temperature. 
   
   
       4 . The carbothermic aluminum production system of  claim 1 , further comprising:
 a feed tube having a distal end terminating proximal said bottom of said reactor.   
   
   
       5 . The carbothermic aluminum production system of  claim 4 , wherein said feed tube extends through said top of said reactor toward said bottom of said reactor. 
   
   
       6 . The carbothermic aluminum production system of  claim 4 , wherein said feed tube extends through said sidewall of said reactor toward said bottom of said reactor. 
   
   
       7 . The carbothermic aluminum production system of  claim 6 , wherein said feed tube extends through said sidewall via a port located proximal said bottom of said reactor. 
   
   
       8 . The carbothermic aluminum production system of  claim 1 , wherein said sidewalls of said reactor extend from said bottom of said reactor to a height such that when said reactor contains molten liquid the hydrostatic pressure of said molten liquid is at least about 0.75 atm as measured proximal said bottom of said reactor. 
   
   
       9 . The carbothermic aluminum production system of  claim 1 , wherein said sidewalls of said reactor extend from said bottom of said reactor to a height such that when said reactor contains molten liquid the hydrostatic pressure of said molten liquid is at least about 1.0 atm as measured proximal said bottom of said reactor. 
   
   
       10 . The carbothermic aluminum production system of  claim 1 , wherein said reactor further comprises:
 a baffle extending from said top of said reactor toward said bottom of said reactor, thereby separating said reactor into a first zone and second zone, said baffle having a terminal end that terminates proximal said bottom of said reactor, thereby defining a passageway between said first zone and said second zone.   
   
   
       11 . The carbothermic aluminum production system of  claim 1 , wherein the length of said baffle is such that when said reactor contains molten liquid, the hydrostatic pressure of said molten liquid proximal said passageway is at least about 0.5 atm as measured proximal said passageway. 
   
   
       12 . The carbothermic aluminum production system of  claim 1 , wherein the length of said baffle is such that when said reactor contains molten liquid, the hydrostatic pressure of said molten liquid proximal said passageway is at least about 0.75 atm as measured proximal said passageway. 
   
   
       13 . The carbothermic aluminum production system of  claim 1 , wherein the length of said baffle is such that when said reactor contains molten liquid, the hydrostatic pressure of said molten liquid proximal said passageway is at least about 1.0 atm as measured proximal said passageway. 
   
   
       14 . A method of carbothermically producing aluminum, the method comprising:
 heating an aluminum slag in a reactor having a plurality of electrodes, said aluminum slag having a hydrostatic pressure of at least about 0.50 atm as measured proximal a bottom portion of said reactor;   recovering aluminum from said reactor; and   introducing at least one of aluminum carbide, aluminum oxide and a carbonaceous material into said reactor via a feed tube   
   
   
       15 . The method of  claim 14 , wherein said feed tube extends substantially vertically through said reactor and terminates proximal a bottom portion of said reactor. 
   
   
       16 . The method of  claim 14 , wherein said feed tube enters said reactor through a sidewall proximal a bottom portion of said reactor. 
   
   
       17 . The method of  claim 16 , wherein said feed tube is substantially horizontal. 
   
   
       18 . The method of  claim 14 , wherein said plurality of electrodes are operable to heat said aluminum slag such that a selected temperature gradient is achieved in said aluminum slag. 
   
   
       19 . The method of  claim 14 , wherein said reactor comprises a baffle separating said reactor into a first zone and a second zone, said baffle having a terminal end that terminates proximal said bottom portion of said reactor, thereby defining a passageway between said first zone and said second zone, the method further comprising:
 flowing said aluminum slag from said first zone to said second zone proximal said baffle, wherein the hydrostatic pressure proximal said passageway during said flowing step is at least about 0.5 atm.   
   
   
       20 . The method of  claim 19 , wherein the hydrostatic pressure proximal said passageway during said flowing step is at least about 0.75 atm.