Ann: Exploration Update, page-38

I do not know the difference in heat to get ore up to melting point compared to steel scrap , but based on steel scrap it but it Looks like around $625KWH would be needed to melt 1 tonne of steel scrap but there is also the copper to melt so lets say 700KWh

700KwH * say US$0.15Kwh = $105.00 heating cost to melt the ore



55% TO 65% (MAX) OVERALL ENERGY EFFICIENT FURNACES ARE AVAILABLE.
FOR M.S. SCRAP
SPECIFIC HEAT = 0.682 KJ / KG DEG CENTI.
LATENT HEAT = 272.0 KJ / KG
SPECIFIC HEAT REQD TO MELT 1000KGS OF M.S SCRAP WILL BE, @ 1650ºC
= 100 × 0.682 × (1650 - 30)
-------------------------------------- KWH
3600
= 307 KWH
LATENT HEAT REQD,
272 × 1000 / 3600
76 KWH.
HEAT FOR SLAGE
1.6 × 25 / 3.6
12 KWH.
TOTAL KWH THEORETICALLY REQD FOR MELTING IS 395 KWH.
APPROX 400 KWH REQD TO MELT M.S OF 1000KGS TO 1650DEG CENTIGRADE.
IF THE FURNACE CONSUMES 625 KWHITON THAN THE FURNACE IS OVERALL ENERGY EFFIECIENT 65%.
[ i.e. 400 ÷ 625 = 64 % ]

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