Resit Assignment
The resit case study is an INDIVIDUAL REPORT.
ELECTRONIC SUBMISSION ONLY via Canvas until
Any reports not following the submission format and guidelines
below will not be marked!
A double-effect evaporator (two evaporators in series) is used to produce
fresh water from seawater containing 3.5 wt% dissolved salts. A flowchart
for the process is shown here.
H₂O(V)
P=0.6 bar
H₂O(v)
Saturated
4 bar
Seawater, 300 K
3.5 wt% salt, 5000 kg/h
P=0.2 bar
Brine
5.5 wt% salt
H₂0(1)
sat'd, 4 bar
H₂O(v)
H₂O(l)
sat'd,
0.6 bar
Newcastle
University
Brine
Condenser
Fresh water
product
Seawater enters the first effect at 300 K at a rate of 5000 kg/h, and
saturated steam at 4.00 bar absolute is fed into a tube bundle in the first
effect. The steam condenses at 4.00 bar, and the condensate is withdrawn
at the saturation temperature corresponding to this pressure.
The heat given up by the steam condensing in the tubes causes water to
evaporate from the brine solution at the pressure of 0.60 bar maintained
in the effect. The exiting brine contains 5.5 wt% salt. The steam generated
in the first effect is fed to a tube bundle in the second effect. The
condensate from the bundle and the steam generated in the second effect
at a pressure of 0.20 bar constitute the fresh water produced in the
process.
In solving the problems to be given, assume that the brine solutions in/nboth effects have the physical properties of pure water and that the
effects operate adiabatically.
Your report should contain at least the following:
1) Detailed mass and energy balances for the process, with
calculations in an appendix.
2) Presentation of flow sheet software results, comparison with manual
calculations with discussion (submit your Aspen Hysis file aside).
3) An assessment of the sustainability of this process (0.5-1 page
Newcastle
University
guidance);
4) A safety assessment of the process, highlighting major hazards and
measures that could be taken to minimize these hazards (0.5-1 page
guidance);
one of the
5) Description of the materials selection process t
evaporators (0.5-1 page guidance).
Report Format and Submission Guidelines:
• 6 sides of A4 Maximum, plus appendices;
• 12 pt Times New Roman;
•
2.5 cm margins around the entire document;
•
Title, student number and name must be on the front page;
Match the sections of the report to the sections indicated
above;
• Good report writing guidelines (cf. CME1025) must be followed, i.e.
use of significant figures, explicit use of variables, good presentation
of graphs and tables, etc.
Report Marking Scheme
Mass and Energy balances
Process simulation flow sheet software
Health and Safety
Assessment of the sustainability of the plant
15%
Materials selection
Marks and Feedback:
Feedback will be given via CANVAS;
The marks will be released via CANVAS.
25%
25%
20%
15%
Ensure that you submit the correct files using the correct
submission portal. It will not be possible to retrieve your files
after submission, and you will only be allowed to submit once!
Fig: 1
Fig: 2
Fig: 3