OABA May Meeting May 14, 2005

Experiment Notes - ECONONORSE Smelter

Leader : Darrell Markewitz

Assisting: Neil Peterson / John Burton

Recorder : Neil Peterson / Vandy Simpson

Charcoal Monkeys: Gus Gissing / Ken Cook / Sam Falizone

TIME EVENT MEASUREMENT

Relative Elapsed Relative Absolute Total

Fuel Ore

-00 00 start preheat with wood splits

-35 35 addition rough charcoal, gentle air blast

-45 45 fill with rough charcoal

12:00 00 timer reset - smelt begins

12:10 10 first measured charcoal 1 4 lbs* 4 lbs

12:20 10 charcoal 2 8 lbs

12:40 20 charcoal 3 12 lbs

12:51 11 seed charge 1 .75 lbs .75 lbs

charcoal 4 16 lbs

1:06 15 seed charge 2 .75 lbs 1.5 lbs

1:09 18 charcoal 5 20 lbs

1:32 23 charcoal 6 24 lbs

26 seed charge 3 .75 lbs 2.25 lbs

1:40 addition of second hand crank blower

1:45 tuyere replaced with copper

***

2:02 30 charcoal 7 28 lbs

seed charge 4 .75 lbs 3 lbs

2:12 10 charcoal 8 32 lbs

2:17 15 seed charge 5 .75 lbs 3.75 lbs

2:29 17 charcoal 9 36 lbs

12 seed charge 6 .75 lbs 4.5 lbs

2:44 15 charcoal 10 40 lbs

15 seed charge 7 .75 lbs 5.25 lbs

2:49 5 charcoal 11 44 lbs

5 seed charge 8 .75 lbs 6 lbs

2:53 4 charcoal 12 48 lbs

4 full charge 9 1.5 lbs 7.5 lbs

3:00 7 charcoal 13 52 lbs

3:10 17 half charge 10 .75 lbs 8.25 lbs

3:12 12 charcoal 14 56 lbs

2 full charge 11 1.5 lb 9.75 lbs

***

3:23 11 charcoal 15 60 lbs

full charge 12 1.5 lb 11.25 lbs

3:31 12 charcoal 16 64 lbs

full charge 13 1.5 lbs 12.75 lbs

3:38 7 charcoal 17 68 lbs

full charge 14 3 lbs 15.75 lbs

3:50 12 charcoal 18 72 lbs

full charge 15 3 lbs 18.75 lbs

3.58 8 charcoal 19 76 lbs

full charge 16 3 lbs 21.75 lbs

4:11 13 charcoal 20 80 lbs

full charge 17 2.25 lbs 24 lbs

4:21 first tapping attempt

4:23 12 charcoal 21 84 lbs

half charge 18 .75 lbs 24.75 lbs

4:26 3 charcoal 22 88 lbs

full charge 19 3.75 lbs 28.5 lbs

4:36 10 charcoal 23 92 lbs

full charge 20 2.25 lbs 30.75 lbs

second tapping attempt

4:44 12 charcoal 24 96 lbs

full charge 21 2.25 lbs 33 lbs

4:52 12 charcoal 25 100 lbs

full charge 22 2.25 lbs 35.25 lbs

5:02 10 charcoal 26 104 lbs

full charge 23 3 lbs 38.25 lbs

5:15 13 charcoal 27 108 lbs

full charge 24 2.25 lbs 40.5 lbs

5:22 7 charcoal 28 112 lbs

full charge 25 3 lbs 43.5 lbs

5:32 10 charcoal 29 116 lbs

full charge 26 3.75 lbs 47.25 lbs

5:43 11 charcoal 30 120 lbs

full charge 27 3 lbs 50.25 lbs

5:54 11 charcoal 31 124 lbs

full charge 28 3 lbs 53.25 lbs

6:08 12 charcoal 32 128 lbs

full charge 29 3.75 47 lbs

6:29 tap slag and recycle 3 lbs ¥

(one charcoal addition may be missing here)

6:34 26 charcoal 31 132 lbs

6:43 11 charcoal 32 136 lbs

6:52 11 charcoal 33 140 lbs

6:59 7 charcoal 34 144 lbs

7:06 7 charcoal 35 148 lbs

7:13 start to dismantle smelter

7:26 bloom removed

NOTES:

All ore charges are based on a ‘standard scoop’ - taconite weight of .75 lbs

* All charcoal charges are based on a ‘standard pail’ - weight of 4 lbs

¥ This is estimated weight only, not added into charge total

*** Marks areas were records are suspect

YIELD: 21 lbs (estimated)

This represents 45 % yield from roasted ore weight

Bloom was significantly ‘trough’ shaped - this a result from changes in the tuyere angle during the smelt. Weight estimate is for the main bloom only, and does not include smaller (walnut sized) fragments. Roughly one third of the mass was cut off while still hot from the smelt. The remaining section weighs 14 lbs.

Considerable trouble was experienced during the early part of the sequence with air delivery. Although checked before storage, the main blower did not work at first attempt. A smaller (less volume) vacuum blower was initially employed. Concern developed that it was not producing enough air volume, so a second hand cranked blower was added in conjunction. The main blower was checked and re-installed to the smelter about hour three.

The use of a packing mixture of roughly 50 / 50 beach sand and rough saw dust proved a mixed blessing. First, gaps in the brick structure were not sealed with clay. During firing, the sawdust element burned, and the heated sand ran like a fluid through the cracks. Continual addition of replacement packing proved necessary.

As it turned out, the pure taconite ore lacked the silica content to provide for the required slag. Normally this would have been a major problem, as the firebrick adds little silica (through melting). In this smelt, the sand from the packing actually added the required silica content to create plentiful slag - required to control the carbon content of the bloom.

One third of the bloom was given to Lloyd Johnson. He latter consolidated and finished the mass into a workable bar. He reports that the material created was ‘nice soft workable iron’.

2021 Note : This report was recovered from a much older software version. For this reason the formatting is less than ideal.