Question

A glass melting furnace is burning ethene (C2H4) in pure oxygen (not air). The furnace
operates at an equivalence ratio of 0.9 and consumes 30 kmol / hr of ethene.
A. Determine the energy input rate based on the LHV of the fuel. Express your result in
both kW and Btu / hr.
B. Determine the O2 consumption rate in kmol / hr and kg / s

Answer 1

Explanation:

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.