|
Worked Example
Consider
the following extensions to this initial problem
If
you need to supply 300 m3/hr to the distillation
column what is the most profitable split of crude.
This
type of calculation is done by computer as it involves an
enormous number of calculations done very quickly.
However
we can mimic the computer by choosing just two particular
ways of making 300 m3/hr and calculating and comparing
the end profits.
Let
us take the following two cases
| |
inputs
|
|
total
|
|
outputs
|
|
total
|
| |
Crude 1
|
Crude 2
|
|
LPG
|
LVN
|
Petrol
|
|
|
Case1
|
150
|
150
|
300
|
37.5
|
67.5
|
195
|
300
|
|
Case 2
|
200
|
100
|
300
|
40
|
70
|
190
|
300
|
For
each example we can calculate the costs and money made for
the two different input flowrates. In each case a total of
300 m3/hr is being fed in but because the streams
are in different proportions different amount of LPG, LVN
and Petrol are produced.
| If
the products are worth |
|
LPG $10
/m3 |
| |
|
LVN $20
/m3 |
| |
|
Petrol $30
/m3 |
| Crude
1 costs |
$15
/m3 |
|
| Crude
2 costs |
$25
/m3 |
|
How much per day
will we make in each case?
|