50.1K

Verified Solution

Link Copied!

Methane is a clean gaseous fuel used in chemical industriesworldwide. 1000 kmol/hr of methane is combusted in a burner toprovide heat. The combustion reaction is:

CH4 + O2 à CO2 + H2O

Air is used for combustion and it can be assumed to becomposed of 20% oxygen and 80% nitrogen. Nitrogen is consideredinert and does not undergo any oxidation reaction.

The inlet pressure for all stream is atmospheric.

Use a conversion reactor in VMGSim simulation package tosimulate burner. Assume that the heat loss to surrounding isnegligible (very well insulated burner). Pressure drop across theburner is assumed to be 10 kPa. Assume adiabatic conditions withmethane conversion of 95%. Follow the simulation guideline (to beprovided) and having converged the simulation, export the resultsto WORD. The followings can be easily determined from theresults:

1- Properties of exhaust gases such as average specific heat,enthalpy, entropy, thermal conductivity, viscosity etc.

2- Composition of exhaust gases from the burner in mole% andmass%

3- The flow rate of each component in the exhaust gas inKg/h

4- Temperature of exhaust gases

5- Pressure of exhaust gases

6- Volumetric flow rate of gases

Now repeat the simulation assuming the you use 50% excess air.You need to increase the mole fraction in the inlet stream toburner. Keeping all other conditions the same, compare the resultsof the two simulation and answer the following questions in thereport. You may add these to the report (exported to WORD).

1- Is the final temperature lower or higher? Why?

2- Is there a change in reaction enthalpy? Explain.

3- Is there any change in specific heats?