Posted by Brandon on .
A glass melting furnace is burning ethene in pure oxygen (not air). The furnace operates at an equivalence ratio of 0.9 and consumes 30 kmol/hr of ethene. Determine the energy input rate based on the LHV of the fuel in terms of kW.
•Determine O2 consumption rate in kmol/hr.
Ethene, also known as ethylene, is C2H4. The lower heating value (LHV) is 11,270 kcal/kg.
You don't need that number to answer the question.
The balanced reaction is
C2H4 + 3 O2 -> 2 CO2 + 2 H2O
30 kmol/hr of ethene requires 90 kmol/hr of O2 for complete combustion. But with an equivalence ratio of 0.9, you use excess O2 by a ratio 1/0.9 (lean mixture). That means you use 100 kmol/hr of O2.