Consider the component CYO that has been selected in the configuration. (The
code FU/CYO in this case indicates that the refinery stream CYO is routed to fuel.)
The quantity of the stream CYO that enters the fuel blend is 1,457 BPCD. Now
consider the component “HBM.” This has not been selected in the basis, and this
stream has a DJ value (i.e., no prefix). To route the “HBM” stream to fuel forcibly
would cost $0.6095/bbl. This information is interesting, but has no real value unless
the ranges for their streams are known.
Because the FU/CYO item is selected in the basis, the range data for this is found
in the primal range output (Table 26). Interpreting the statement for this stream in
this output means that optimum volume levels of the solution would not have
changed even if the variable had a very small negative incentive (less than
$0.000001). Further, the situation would not have changed even if this variable
had a positive cost incentive of up to $0.02807/bbl.
Let us now look at the “HBM” variable. This was not chosen in the basis and it
appears in the dual range output (Table 27). Interpreting the data for this item shows
that to route “HBM” to fuel would cost 60 cents/bbl for the first 549 BPCD. All that
is known thereafter is that the cost per barrel over 549 BPCD would increase.
The example chosen here describes the economic analysis of two optional streams
which can be logically routed to a fuel blend. It is emphasized that the BI/DJ and range
outputs, however, contain similar information for all variables whether process units,
refinery streams, product specifications, etc., contained in the model.
Computer Report Writer
The data generated by the computer contains all facts relevant to the solution.
However, to all but a few highly trained people, the data in this form would be
meaningless and of no practical use. The LP system used in this study contained a
specially designed report writer, coded in a language called DART. This converted
and assembled the computer LP output into management orientated reports that could
easily be read and understood without sacrificing the relevant technical content.
Table 26 An extract of the corresponding LP dual range output
LP label
Original activity
Limits of range
Variable affected
Positive volume increment
FU/HBB
0.000000
FU/HRB
0.000000
FU/HBF
0.000000
HF/HBF
0.000000
FU/HBG
0.000000
CCFHSG
0.000000
FU/HBH
0.000000
TEFCYO
0.109287
FU/HBM
0.000000
FU/CYO
0.549070
FU/HRA
0.000000
FU/VBR
0.000000
FU/HRF
0.000000
FU/VBR
0.000000
FU/HRH
0.000000
FU/VBR
0.000000
FU/HSA
0.000000
CCFHSA
0.000000
Petroleum Refinery Planning and Economics
783
code FU/CYO in this case indicates that the refinery stream CYO is routed to fuel.)
The quantity of the stream CYO that enters the fuel blend is 1,457 BPCD. Now
consider the component “HBM.” This has not been selected in the basis, and this
stream has a DJ value (i.e., no prefix). To route the “HBM” stream to fuel forcibly
would cost $0.6095/bbl. This information is interesting, but has no real value unless
the ranges for their streams are known.
Because the FU/CYO item is selected in the basis, the range data for this is found
in the primal range output (Table 26). Interpreting the statement for this stream in
this output means that optimum volume levels of the solution would not have
changed even if the variable had a very small negative incentive (less than
$0.000001). Further, the situation would not have changed even if this variable
had a positive cost incentive of up to $0.02807/bbl.
Let us now look at the “HBM” variable. This was not chosen in the basis and it
appears in the dual range output (Table 27). Interpreting the data for this item shows
that to route “HBM” to fuel would cost 60 cents/bbl for the first 549 BPCD. All that
is known thereafter is that the cost per barrel over 549 BPCD would increase.
The example chosen here describes the economic analysis of two optional streams
which can be logically routed to a fuel blend. It is emphasized that the BI/DJ and range
outputs, however, contain similar information for all variables whether process units,
refinery streams, product specifications, etc., contained in the model.
Computer Report Writer
The data generated by the computer contains all facts relevant to the solution.
However, to all but a few highly trained people, the data in this form would be
meaningless and of no practical use. The LP system used in this study contained a
specially designed report writer, coded in a language called DART. This converted
and assembled the computer LP output into management orientated reports that could
easily be read and understood without sacrificing the relevant technical content.
Table 26 An extract of the corresponding LP dual range output
LP label
Original activity
Limits of range
Variable affected
Positive volume increment
FU/HBB
0.000000
FU/HRB
0.000000
FU/HBF
0.000000
HF/HBF
0.000000
FU/HBG
0.000000
CCFHSG
0.000000
FU/HBH
0.000000
TEFCYO
0.109287
FU/HBM
0.000000
FU/CYO
0.549070
FU/HRA
0.000000
FU/VBR
0.000000
FU/HRF
0.000000
FU/VBR
0.000000
FU/HRH
0.000000
FU/VBR
0.000000
FU/HSA
0.000000
CCFHSA
0.000000
Petroleum Refinery Planning and Economics
783