Reference no: EM132644044

Question 1: If 1 kg of natural gas and 1 kg of biogas are burnt, what is the total flow rate of m^·₄ required for staichiometric and complete combustion, if:
(a) m^·₃ consists of 100 mol% O₂
(b) m^·₃ consist of 50 mol% O₂ and 50 mol% N₂
Take the time basis as 1 hr

For part (b), what is the mol % composition of the exhaust gas?

Question 2: Based on Q5 (a), perform a degree of freedom analysis on your combustion chamber, using:
(i) Species balances (using extents of reaction concept)
(ii) Element balances

Specify all your unknowns, write out all your independent equations, and find your degrees of freedom. You do NOT have to solve these equations in this question.

Question 3: In order to increase the overall conversion of CH₄, C₂H₆. C₃H₈, C₄H₁₀ in the combustion chamber, 50% of the exhaust gas is recycled to the combustion chamber. Assuming the single pass conversion is still 6S'X, find the new Orsat analysis m^·₅ and m^·₆ gas compositions if the overall conversion of CH₄, C₂H₆ , C₃H₈, C₄H₁₀ is 70 % for 1 kg of natural gas and 1 kg of biogas as fresh feed.

Hint: Use an element balance for the overall system, with the same CO₂/CO ratio in the exit. The f5P/fOA ratio is also useful.

Question 4: If you limited your exhaust gas temperature to 130 °C, at 1 atm pressure, what is the volumetric flow rate of gas would be produced in complete combustion of 1 kg/hr of each fuel, with 35% excess air?

Natural Gas

Species                      MW               Formula              1       

Biogas

carbon doxide

Species                      MW                Formula                   

All three submissions are related to the process described below. A natural gas (m^·₁ ) And biogas (m^·₂) are combusted in the combustion chamber, by reacting it with Air entering in stream m^·₃. Combusted gases (m^·₄) are passed through a membrane to separate some or all N₂ (m^·₅) and exhaust gas (m^·₆).