Calculation of the Ore Mixture or Burden for a Blast Furnace. [Volume: 8, Issue: 3, 1889, pp. 130-143]

No. 3.] CHARCOAL IRON WORKERS. 141
Al,0o CaOMgO Fe. P.
0.2 equivalent lias ore, 10.52 parts with. 0.68... 4.50 0.052
1.8 equivalent bog ore, 54.54partswith. 0.54 0.65 21.97 0.654
1.0 equivalent spathic
ore,....... 12.27 parts with... 2.99 2.77.
Total,...... 77.33 partswith. 1.22 3.64 29.24 0.706
Ratio of A1203; [CaOMgO] 1: 3
Amount of iron in mixture 37.8 per cent.
Amount of phosphorus in iron 2.4 per cent.
In this case the amount of phosphorus is not considerably
diminished.
Then comes the question what relation the costs of the two
mixtures bear to each other. An, equality in this respect is only
possible if we consider these costs not according to the unit of
weight of the mixture, but the unit of iron contained in the mixture. For example let the cost of the different ores, including
transportation to the furnace, be as follows:'
1,000 kilos lias ore,................... 9 marks.
1,000 kilos bog ore,................... 6 marks.
1,000 kilos spathic ore,................. 8 marks.
1,000 kilos limestone,.................. 4 marks.
then the cost of burden first calculated without spathic ore would
be:
10.52 parts lias ore with...... 4.50 parts iron, 0.095 marks.
54.54 parts bog ore with...... 21.97 parts iron, 0.327 marks.
7.02 parts limestone with...... parts iron, 0.028 marks.
26.47 parts iron 0.450 marks.
If 26.47 kilos cost 0.45 mark 1000 kilos 17 marks.
The ccst of the second burden with spathic ore would be:
10.52 parts lias ore with...... 4.50 parts iron, 0.095
54.54 parts bog ore with...... 21.97 parts iron, 0.327
12.27 parts spathic ore..... 2.77 parts iron, 0.098
29.24 parts iron, 0.520
Therefore 1,000 kilos would cost 17 marks 78 pfennig, or 78
pfennig more than the other high phosphorus burden, but the
* These figures are only assumptions, but apparently are intended to represent fair averages. Assuming that 1,000 kilogrammes, or one metric ton,
as practically equivalent to one gross ton, and one mark equal to 24 cents,
we will have the following values:
1 gross ton lias ore,........... 2 16
1 gross ton bog ore,.............1 44
1 gross ton spathic ore,.................2 00
1 gross ton limestone,............. 96
-EDITOR.