Combustion Reactions in a Furnace
Combustion Reactions in a Furnace
Fuel is fed to a furnace at and a molar flow rate of . This fuel is one of these hydrocarbons: methane, ethane, acetylene, propane, or butane. The fuel is subject to a combustion reaction in the furnace: , where is the stoichiometric coefficient of the chemical species. An excess of oxygen entering at is used for the combustion reaction, so that the conversion of the fuel is total. You can select the value of the inlet molar flow rate of oxygen and nitrogen. We apply the energy balance for reacting systems using the heat of reaction method [1]. The Demonstration determines:
25°C
100moles/hr
fuel+⇄+O(v)
ν
oxygen
O
2
ν
carbondioxide
CO
2
ν
water
H
2
ν
species
150°C
1. the heat duty in (labeled in the process flowchart) for user-set values of exit temperature of the exhaust gases
kJ/hr
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2. the adiabatic flame temperature (i.e., for =0) labeled in the process flowchart.
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By specifying the exit temperature of the furnace, the enthalpy balance at steady operation requires that excess heat (denoted by ) from the exothermic reaction has to be removed. By specifying adiabatic operations, the heat released by the reaction raises the temperature of the exhaust gases. You can change the inlet molar flow rate of nitrogen and observe its effect on both on and .
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