'Redemption' Smelt
Monday November 6. 2006

Virginia Rock Ore plus Gangue in Norse Short Shaft
'Redemption' bloom
Adding Ore
'Incontinent' Slag Tap
Finished Bloom with slice
TIME   EVENT ORE GANGUE     CHARCOAL AIR  
RELATIVE ELAPSED   ADD (scoops) ADD (scoops) AMOUNT TOTAL TOTAL SETTING VOLUME
      (12 OZ each) (11 OZ each) (as LB *) (as LB*) (4 LB each *)   (litre/min)
                   
:00   start preheat           A 1/4 325
:10               A 1/2 455
:45 45 addtion of carcoal           D 1060
1:00 15 start of main sequence              
                   
0:00 0           4    
0:09 9           8    
0:15 6           12    
0:21 6           16    
0:24   burn column to top of clay              
0:27 6 start addition of gangue         20    
0:35 7     4 3 3 24    
0:41 6     4 3 6 28    
0:46   gangue seen at tuyere              
0:48 7     3 2.25 8.25 32    
0:54 E 6 start addition of ore 4   3 3 36    
1:00 6   4   3 6 40    
1:07 7   4   3 9 44    
1:13 7   4   3 12 48    
1:19 6   4   3 15 52    
1:25 6   4   3 18 56    
1:31 6 last ore charges 2   1.5 19.5 60    
1:36 5 gap to allow ore to settle         64    
1:42 6           68    
1:49 7 resume adding gangue   3 2.25 10.5 72    
    last ore at tuyere              
1:57 8     3 2.25 12.75 76    
2:04 7     3 2.25 15 80    
2:12 8     3 2.25 17.25 84    
2:19 7     3 2.25 19.5 88    
2:22   self tapping              
2:25 6 tap slag added (3 x scoops?)   1 0.75 20.25 92    
2:32 7 last gangue charge   3 2.25 22.5 96    
2:40 8 tap slag added (3 x scoops?)         100    
2:47 7           104    
2:54 7           108    
2:59 5 last gangue hits tuyere         112    
    start burn down phase              
3:20               C 970
3:22               B 1/2 840
3:24 25 start extraction           B 703
                   
          ORE GANGUE CHARCOAL    
    TOTALS LBS   19.5 22.5 112    
      KG   8.9 10.2 50.9    
                   
    BLOOM PRODUCED LBS   15        
      KG   6.8        
      % (E **)   35%        

  NOTES:

*  - The weights used in this table have been rounded up slightly from the actual recorded amounts:
        GANGUE         = 300 gm / 11 oz
         ORE                 =  350 gm / 12 oz
        CHARCOAL    = 1650 gm  / 3 lb 11 oz
The main effect is the slightly larger amount shown for charcoal consumption. This has the effect of INCREASING the acual burn rates from the elapsed times indicated.

** - The overall yield per centages should be considered an estimate only. The total of ore plus gangue was used against the finished bloom weight.

1) Note that the gangue had already been through the smelting process once. This smelt (on 11 / 05) had produced only a few small pieces of iron, about 1 lb in total.  
As much of the slag produced from the Sunday smelt was collected and crushed down to at least 'half walnut' size and re-cyled for the smelt recorded here.

2) The smelter base was positioned at the normal level (about 10 cm below tuyere level.

3) The sequence of high charge rates was suggested by Mike McCarthy at Early Iron 3.

4) This was the SECOND use of the same ceramic tuyere. At the end of the smelt there was minimal damage due to slumping. It is expected that this tuyere will remain effective for addtional smelts

It should be noted that this smelt was undertaken by a SINGLE operator. The smelter was the third use of this clay cobb furnace, which had minor repair to the tap arch. Charcoal was pre-sized. Ore had been roasted, but both ore and gangue was crushed during pre-heat. The total time from hauling gear to the work area to clean up was about  6 hours!

Last Updated on 7/11/06
By Darrell Markewitz
Email: smelt@warehamforge.ca

Text and photography © 1998 - 2007, Darrell Markewitz