# Determine how much coke is required to heat 1.5 tons of scrap iron from 20

**Determine how much coke is required to heat 1.5 tons of scrap iron from 20 degrees to the melting point and melt. The efficiency of the melting furnace is 60%.**

To find out the required mass of coke, heating and melting of the taken iron scrap, we use the formula: ηп = mzhl * (CFe * (tmelt – t0) + λFe) / (qk * mk), from where we express: mk = mzhl * (CFe * (tmelt – t0) + λFe) / (qк * ηп).

Const: СFe – beats. heat capacity of iron (СFe = 452 J / (kg * K)); tmelt – temperature of the beginning of melting (tmelt = 1538.85 ºС); λFe – beats heat of fusion of iron (λFe = 27 * 10 ^ 4 J / kg); qk – beats. heat of combustion of blast furnace coke (qc = 30.4 * 10 ^ 6 J / kg).

Data: mzhl is the mass of iron scrap (mzhl = 1.5 t; in the SI system mzhl = 1.5 * 10 ^ 6 kg); t0 – early. scrap temperature (t0 = 20 ºС); ηп – efficiency of the used melting furnace (ηп = 60% = 0.6).

Let’s perform the calculation: mk = mzhl * (CFe * (tmelt – t0) + λFe) / (qk * ηp) = 1.5 * 10 ^ 3 * (452 * (1538.85 – 20) + 27 * 10 ^ 4) / (30.4 * 10 ^ 6 * 0.6) ≈ 78.7 kg.

Answer: You will need to spend 78.7 kg of blast furnace coke.