Effect of Argon on Blast Furnace Calculations

A P P E N D I X

C Effect of Argon on Blast Furnace Calculations Air contains B1 mol (vol.)% Ar(g) (see Appendix B). We lump this Ar(g) with N2(g) throughout our book - by designating that air contains 21 mol (vol.)% O2(g) and 79 mol (vol.)% N2(g). This appendix shows that representing air’s Ar(g) as N2(g) has little effect on the results of our blast furnace calculations. Like nitrogen, argon passes through the blast furnace without reacting. They both behave the same chemically, so they may be lumped together without misrepresenting blast furnace chemistry. Their enthalpies are slightly different, as discussed in the next section.



5 0:79 kg mol of N2 g  28:216 MJ=kg mol of N2 g 5 22:291 MJ:

C.2 ENTHALPY OF 0.78 KG MOL OF N2(g) 1 0.01 KG MOL OF AR(g) The enthalpy of 1 kg mol of Ar(g) at 930
C (1203.15K) is 18.811 MJ and the enthalpy of 0.78 kg mol of N2(g) 1 0.01 kg mol of Ar(g) at 1200K equals:

0:78 kg mol of N2 g 
28:216 MJ=kg mol of N2 g
1 0:01 kg mol of Ar g  18:811 MJ=kg mol of Ar g 5 22:197 MJ

difference is fð22:291 2 22:197Þ=22:291g which will have very little effect on our matrix calculations. The

 100% 5 0:4%

C.1 ENTHALPY OF 0.79 KG MOL OF N2(g) The enthalpy of 1 kg mol of N2(g) at 930
C (1203.15K) from JANAF1 is; 28:216 MJ

and the enthalpy of 0.79 kg mol of N2(g) at 930
C (1203.15K):

Reference 1. JANAF. NIST JANAF thermochemical tables. Retrieved on January 1, 2016 by Googling NIST JANAF Thermochemical Tables; 2016.

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