(Thermal Energy Conservation)
Name: ________________________________________ Date: __________________
Through this lab exercise, the principle of conservation of charge will be demonstrated
using an adopted problem-solving methodology and a simple Matlab exercise.
Matlab 2007 or higher
GASBUGS INC. is actually a division of a much larger alternate, fuel-generating
corporation known as BIOFUELS INTERNATIONAL. One thing this company produces
is ethanol (C2H6O) from an industrial process that uses a type of yeast (Saccharomyces
cerevisiae). The elemental formula of S. cerevisiae is CH1.874 O0.45 N0.2 and it has a heat
of combustion of approximately -21.2 kJ/g. In their batch process, .25lb m NH3 and
5.0lbm glucose are combined with the yeast at 25 oC. After the reaction goes to
completion (at least one of the starting reactants is used up), 1. 4 lb m of ethanol is
produced. The unbalanced reaction for this process is:
C6H12O6 (l) + NH3 (g) → C3H8O3 (l) + C2H6O (l) + (0.59)CH1.74 O0.45 N0.2 + CO2 (g) + H2O (l)
Note: (C3H8O3 )and that the ratio of NH3 to H2O is 1:1.)
You are told that it is likely that too much glucose is being added in the batch reactor
process. It is your goal as the production engineering support specialist working for
BIOFUELS INTERNATIONAL to model this scenario to determine how much
unnecessary glucose is being added to reduce waste and cost.
Follow the 4 steps of methodology for solving problems on pp. 44–46 of your
textbook to set up the model.
Using MATLAB, create a plot that demonstrates the impact on ethanol production
as the amount of glucose in the reactor varies from 1.0 lb m to 10 lbm.
(1) How much excess glucose was being added to the reactor?
(2) What is the ideal amount needed?
(3) How much heat was produced and subsequently removed from the system?
(4) Interpret the Matlab plot produced.