The Objectives listed below are minimum objectives:
Teams 3, 4, 5, 10: The object of the experiment is to investigate the effect of varying inlet shell-side pressure on the separation of air by membrane permeation.
Teams 1, 6, 8, 11: The object of the experiment is to investigate the effect of varying the outlet tube-side pressure on the separation of air by membrane permeation.
Teams 2, 7, 9: The object of the experiment is to investigate the effect of varying the inlet shell-side flow rate on the separation of air by membrane permeation.
The equipment to be used is a Permea Prism™ membrane separator. Air is the inlet feed stream. The inlet air is split into nitrogen-rich and oxygen-rich product streams. The system may be operated with 1, 2, 3, or 4 tubes.
A conceptual diagram of the unit is attached (will be at some future date) for your information.Prelab Report
Your Prelab Report will consist of a written report and an oral question and answer session. It will be graded on the following basis:
| Experimental Plan (20%) | What are the goals and objectives of your experimentation? What is your underlying hypothesis? What experiments do you plan to run in order to generate the data necessary to satisfy your goals and objects? How do you plan to prove or disprove your hypothesis? Be specific!! For example, what inlet and outlet pressures will you operate at? What range of P? Delta P? What other process parameters will you vary? hold constant? |
| Experimental Procedure (15%) | Procedurally (and mechanically), how do you intend to operate the experimental apparatus? What valves do you intend to open first? last? How do you plan to control whatever it is that you plan to control? A step-by-step recipe is nice. Reference to a labeled drawing of the apparatus is suggested!! |
| Calculation Plan/Procedure (20%) | Once you have taken the raw data, how do you plan to manipulate it? What ‘theoretical' equations are you going to use to fit the data? What basic mass-transfer principles govern the separation? How are you going to relate your results to these basic mass-transfer principles? Be sure to include a sample calculation (using dummy data if necessary) to illustrate your specific, expected calculation procedure. |
| Expected Data and Results (20%) | Self-explanatory. In case this isn't 'self-explanatory' what I want are answers to the questions, "What effects will varying your selected operating parameters have on the expected results?" and "Why?" (this is a big one, support with theory and equations). |
| Error Analysis (10%) | How do you plan to estimate the experimental error inherent in the apparatus and measurements? How do you know whether or not the trends that you observe experimentally are significant? Be sure to propose specific strategies (including the appropriate equations) in your report. |
| Questions and Answers (15%) | A group representative, selected by blind draw, will answer questions on behalf of the group. |
All members of the group must attend the prelab meeting. At that time, one memberProgress Reportwill be selected (by blind draw) who will answer all of the questions. The entire group will receive a grade based on the answers.
A Progress Report will be due at the end of the business day directly preceding your second laboratory period. The Progress Report should address what was accomplished in Week One, including up-to-date calculations and a preliminary analysis of the data, and what the specific lab plan and procedure is to be used for Week Two. The Week Two plan is expected to be related in some way to the results of the work accomplished during Week One.Final ReportIt is to your advantage to submit a relatively complete (experimental results, calculations, and graphs) Progress Report. Even thought the Progress Report is not worth very many points, I will grade it rigorously and point out any calculational errors or data quirks that I may find. You will then be able to correct any of these potential deficiencies in time not to suffer major damage on the Final Report.
Your written Final Report will be graded on the following basis:
| Summary | 15% |
| Presentation of Results | 25% |
| Discussion of Results/Analysis of Data/Conclusions | 45% |
| Appropriate Application of Statistical Analysis | 10% |
| Appendices/Example Calculations/Supplementary Data | 5% |
The Final Report should contain most of the information included in the Prelab Report, but in a more polished, finished form. Remember, you are reporting on work that you completed based on your plan. The plan was reported in the Prelab Report and any meaningful modifications of the plan should have been reported in the Progress Report.
The ‘Summary' should include a restatement of the goals and objectives of the experiment, a brief recounting of the procedure, and key results (do not be afraid to include numbers, we are a quantitative profession) and discussion.The ‘Presentation of Results' should include your choice of the best method to present your results and a sample of how the calculations were performed. The quality of graphs and tables used in the report will impact on grading. Make sure that every graph and table included here "tells a story" and is used in the 'Discussion' section to illustrate a point and/or support a statement that you make. Large data tables and tables and figures not referred directly to in the 'Discussion' or other sections should be placed in the 'Appendix'.
The ‘Discussion' should include a comparison of your results with what was expected, an analysis of your results as regards theory, and a quantitative error analysis including an estimate of the significance of your results. Make sure that your 'comparison to theory' includes equations and quantitative as well as qualitative statements.
The 'Statistics' grade is not associated with any particular section. Rather, it is based on your appropriate use of statistics. Questions that you might want to answer include: "What is the reproducibility of my data?", "Have I included defined error bars on my graphs?" (The answer here should be 'yes'!), "Are the trends/effects that I claim are in the data statistically significant? At what level?".
'Appendices': At a minimum, a complete sample calculation (using a data point that you generated) should be included in the appendix.
The total experiment grade will be scored on the following basis.
Prelab Report 35% Progress Report 10% Final Report 55%
Note: The Prelab and Progress Report percentages sum to 45% (replacing the 50% for the Prelab Report reported in the ChE 415 Main Page).
Note: Report writingand data presentation
are important. Major points will be deducted for poor grammar and sentence structure, misspellings, and poor graphing.
References
A brief list of references:
Davis, R.A., and O.C. Sandall, "A Membrane Gas Separation Experiment for the Undergraduate Laboratory," Chemical Engineering Education, 25(1), 10-15 (1990).
(Last modified on 11/12/99 @ 1101) 