100 
The N.Z. Journal of Science and Technology. 
[Mar, 
Table 3. 
Calcium Carbide.—Materials and Power required per Ton of 86 per cerd. 
Carbide packed for Sale. 
Losses in crushing, handling, and packing 
Commercial carbide manufactured 
Pure carbide manufactured : 1-05 X 0-86 
Quantity of 88-4 per cent, coke required, allowing 2 per cent, loss of 
carbon— 
0-564 X 0-903 X 1*02-4- 0-884 
Quantity purchased, allowing for losses (say) 
Quantity of 96-5 per cent, lime required, allowing 12-5 per cent, loss of 
‘ CaO— 
0-875 X 1-125 x 0-903 d- 0-965 
Quantity purchased, allowing for losses- (say) 
Quantity of 98 per cent, limestone required 
Energy utilized per ton of 86 per cent, carbide produced (calculated) 
Energy input into furnace per ton of 86 per cent, carbide produced 
with a furnace efficiency of 50 per cent. 
Energy delivered to works per ton of 86 per cent, carbide produced, 
assuming a loss of 10 per cent, in conductors and auxiliary 
apparatus : 4700/0-9 
Energy delivered to works per ton of 86 per cent, carbide packed for 
sale, with 5 per cent, loss in crushing and packing : 5222 x 1-05 
Carbide of 86 per cent, quality produced per horse-power year of 8,000 
hours input into furnace : 8000 X 0-746 d- 4700 
Carbide of 86 per cent, quality produced per horse-power year delivered 
to works : 1-27 X 0-9 
Carbide of 86 per cent, quality sold per horse-power year delivered to 
works : 1-143 d- 1-05 
Carbon electrodes, 66 lb. per ton of carbide produced or 66 X 1-05 per 
ton sold 
4-8 per cent. 
1-05 tons. 
0-903 „ 
0-587 „ 
0-600 „ 
0-920 ., 
0-95 „ 
1-62 „ 
2,350 kw.-hr 
4,700 „ 
5,222 „ 
5,480 „ 
1-27 tons. 
M43 „ 
1-09 „ 
69-3 lb. 
Table 4. 
Calcium Carbide.—Cost of producing 1,000 Tons per Annum of Packed 
Carbide of 86 per cent. Quality, corresponding to a Furnace-yield of 
1,050 Tons, and requiring a Furnace of 827 Horse-power and a Total 
of 910 Horse-power for all Purposes. Capital Investment, £12,000. 
— 
Per Annum. 
Per Ton. 
£ 
£ 
s. 
d. 
Coke : 0-6 X 1000 = 600 tons, at £1 10s. 
• c 
900 
0 
18 
0 
Lime : 0-95 X 1000 = 950 tons, at £2 12s. 6d. 
• » 
2,494 
2 
9 
10 
Power : 910 h.p., at £4 per horse-power year 
. . 
3,640 
3 
12 
10 
Labour:— 
£ 
s. 
d. 
Furnace-room men, 9 at £4 per week 
36 
0 
0- 
Electrode-mounter, 1 at £4 per week 
4 
0 
0 
Regulating-boys, 3 at £2 per week 
6 
0 
0 
Crushing and packing, 4 at £3 12s. per week 
14 
8 
0 
Raw materials, 2 at £3 per week 
6 
0 
0 
Foreman, 1 at £4 10s. per week 
4 
10 
0 
Men and boys, 20, per week .. 
70 
18 
0 
Total per annum 
. • 
3,687 
3 
13 
9 
Renewal of electrodes : 69-3 lb. Tier ton at 4d. per pound 
= 
£1 
3s. 2d. per ton : 1,000 tons at £1 3s. 2d. 
1,159 
1 
3 
2 
Maintenance and renewals of furnace and plant 
400 
0 
8 
0 
Packing, at £2 10s. per ton of carbide 
2,500 
2 
10 
0 
Management and general 
1,500 
1 
10 
0 
Depreciation, at 8 per cent, on capital 
960 
0 
19 
2 
Total cost of production . . 
16,760 
17 
4 
9 
Profit at (say) 10 per cent, on capital 
1,200 
1 
4 
0 
Selling-price 
17,960 
18 
8 
9 
