of natural gas is burned in a remelting furnace, which operates 24 hours/day, 300 days in a year. The natural gas analyses and . Dry combustion air is excess than theoretical requirements. Flue gas enters the stack at . Volumes are given at and 1 atmospheric pressure.
It is proposed to install a preheater which will cool the flue gases from to . It may be assumed that of the heat recovered from flue gases is transferred to air. Calculate annual fuel saving resulting due to preheater installation. Also calculate carbon affect generation.
The heat of combustion values are:
And sensible heat in POC is
POC
H1200-H298 {Kcal (kg mole)-1}
H800-H298{Kcal (kg mole)-1}
CO2
10650
5458
H2O(V)
8217
4403
O2
7040
3786
N2
6728
3600
Solution: solution is given in brief.
Heat of combustion for the reaction
Now fuel saving/Year will lead to reduction in which is equal.
of natural gas is burned in a remelting furnace, which operates 24 hours/day, 300 days in a year. The natural gas analyses 
and 
. Dry combustion air is 
excess than theoretical requirements. Flue gas enters the stack at 
. Volumes are given at 
and 1 atmospheric pressure.
. It may be assumed that 
of the heat recovered from flue gases is transferred to air. Calculate annual fuel saving resulting due to preheater installation. Also calculate carbon affect generation. 
which is equal
.
