Combustion PSETs

Question 1

Determine the theoretical moles of dry air required for the
combustion of one mole of refinery gases containing 6% H2S, 5% H2, 57% C3H8, 2% CO2, and 30% C4H10.

Answer 1

4.915

Question 2

A furnace is fired with petroleum oil containing 80% C, 13% H, 3% S, 1% N and 3% O. Determine the moles theoretical air required for the
combustion of one kg of oil.

Answer 2

0.4722

Question 3

Calculate the gross and net calorific value of a natural gas at 25oC
which has the following composition: 89.4% CH4, 5% C2H6, 1.9% C3H8, 0.4% i-C4H10, 0.6% n-C4H10, 0.7% CO2 and 2%N2 in MJ/kmol

Answer 3

945.52

Question 4

Pure ethane is burned completely in 20% excess air. Air is supplied at 25oC, 740 torrs and is substantially dry. Calculate %CO2 and kg dry air supplied/kg of fuel gas

Answer 4

10.81%, 19.33

Question 5

Pure dry hydrogen gas is burned completely using 100% excess air. Determine the %O2 in the flue gas in the complete analysis

Answer 5

9.5%

Question 6

Pure methane is burned with 40% excess air and 25% of its carbon content is converted to CO the rest to CO2. 90% of its hydrogen burns to water, the rest remains as unburned H2. Air supplied is at 23oC, 75 mmHg with 80% RH. Calculate %CO2

Answer 6

5.88%