Chemical Engineering Concepts 1
Final Examination Fall, 2000
December 7, 2000 9:00 a.m. – 12:00 Noon
Exam Type: Special Materials
Aids Permitted Aids Not Permitted
Felder and Rousseau Old exams and their solutions
Conversion Tables Assignment solutions
Course Notes Tutorial Quiz solutions
Calculator Other Textbooks
Student Name: _______________________________ K-Section: ____________
Student ID Number: ___________________
Instructions and Information
1. START EACH QUESTION ON THE QUESTION PAPER.
If you need more space, there is a blank page at the end, or you can use the back of the page. If you
prefer, you can ask for an exam booklet, and continue your solution in it.
If you use an exam booklet, make sure you put your name and K-section on the front page.
2. All questions are required and are of equal mark value, though they may not be of equal
difficulty. You should read the Question Paper and start with the easiest problem for you.
3. READ the question carefully to make sure you understand what you are being asked to do. Do not
be afraid to ask questions: the worst that can happen is that I won’t answer.
4 Part marks are given for partial solutions which demonstrate an understanding of the concepts.
Therefore, show all steps in your solution, and state any assumptions that you make.
5. Data not given in the problem statements can be found in Felder & Rousseau.
6. At the end of the examination, please remain seated until all exams have been collected. If you have
used an exam booklet, put your question paper unfolded inside the exam booklet.
If you detach any pages of the question paper, please make sure that your name is on each sheet so
you get credit for it if the pages get mixed in with those of other students.
Marking Scheme: Question Value Mark
Page 1 of 7 PROBLEM NO. 1
Synthesis gas for ammonia manufacture is fed to a reactor with N and 2 in sto2chiometric ratio.
The N s2ream to the synthesis process which produces the synthesis gas contains argon in the ratio of 1
mol Ar/78 mol N . T2e single-pass conversion of the ammonia reactor is 23%. All the ammonia in the
product stream is separated by condensation and the unreacted gas is recycled. From experiments, you
found that, in order for the process to work properly, it is necessary to have a vent stream from the
recycle line which amounts of 0.02 moles per mole of synthesis gas fed to the system. Determine:
a) the mole percent argon in the fresh synthesis gas feed; b) the recycle/synthesis gas flow ratio; and c)
the overall conversion for the process.