Back to results
US 4,238,212 AGranted
Control of a fractional distillation column
AssigneePhillips Petroleum Company
InventorJohn E. Anderson
Life of this patent
Estimating the term…
Abstract
A control system for a fractional distillation column, where the feed to the fractional distillation column is supplied from at least one separator, is disclosed in which overloading of the fractional distillation column is prevented by monitoring a control parameter associated with the fractional distillation column which indicates that the fractional distillation column is being overloaded. The flow of the feed from the at least one separator is manipulated to maintain the control parameter which indicates that the fractional distillation column is being overloaded within desired limits. The feed to the at least one separator is manipulated to maintain the liquid level in the at least one separator within desired limits.
Claims19
Apparatus comprising:
- at least one separator means;
- means for supplying a first feed stream to said at least one separator means;
- a fractional distillation column means;
- means for supplying a second feed stream from said at least one separator means to said fractional distillation column means;
- means for calculating a first signal representative of the predicted desired flow rate of said second feed stream required to prevent flooding of said fractional distillation column means;
- means for establishing a second signal representative of the actual flow rate of said second feed stream;
- means for comparing said first signal and said second signal and for establishing a third signal responsive to the difference between said first signal and said second signal;
- means for manipulating the flow rate of said second feed stream in response to said third signal;
- means for calculating a fourth signal representative of the predicted desired flow rate of said first feed stream required to prevent flooding of said fractional distillation column means;
- means for calculating a fifth signal representative of a correction factor utilized to maintain the liquid level in said at least one separator within desired limits;
- means for combining said fourth signal and said fifth signal to establish a sixth signal representative of a modified predicted desired flow rate of said first feed stream required to both prevent flooding of said fractional distillation column means and required to maintain the liquid level in said at least one separator means within desired limits;
- means for establishing a seventh signal representative of the actual flow rate of said first feed stream;
- means for comparing said sixth signal and said seventh signal and for establishing an eighth signal responsive to the difference between said sixth signal and said seventh signal;
- and
- means for manipulating the flow rate of said first feed stream in response to said eighth signal.
12 more elements
Apparatus comprising:
- at least one separator means;
- means for supplying a first feed stream to said at least one separator means;
- a first fractional distillation column means;
- means for supplying a second feed stream from said at least one separator means to said first fractional distillation column means;
- a second fractional distillation column means;
- means for supplying a third feed stream from said first fractional distillation column means to said second fractional distillation column means;
- means for calculating a first signal representative of the predicted desired flow rate of said second feed stream required to prevent flooding of said first fractional distillation column means and said second fractional distillation column means;
- means for establishing a second signal representative of the actual flow rate of said second feed stream;
- means for comparing said first signal and said second signal and for establishing a third signal responsive to the difference between said first signal and said second signal;
- means for manipulating the flow rate of said second feed stream in response to said third signal;
- means for calculating a fourth signal representative of the predicted desired flow rate of said first feed stream required to prevent flooding of said first fractional distillation column means and said second fractional distillation column means;
- menas for calculating a fifth signal representative of a correction factor utilized to maintain the liquid level in said at least one separator within desired limits;
- means for combining said fourth signal and said fifth signal to establish a sixth signal representative of a modified predicted desired flow rate of said first feed stream required to both prevent flooding of said first fractional distillation column means and said second fractional distillation column means and required to maintain the liquid level in said at least one separator means within desired limits;
- means for establishing a seventh signal representative of the actual flow rate of said first feed stream;
- means for comparing said sixth signal and said seventh signal and for establishing an eighth signal responsive to the difference between said sixth signal and said seventh signal;
- and
- means for manipulating the flow rate of said first feed stream in response to said eighth signal.
14 more elements
Apparatus comprising:
- a first separator means;
- a second separator means;
- means for supplying a first feed stream to said first separator means;
- means for supplying the vapor portion of said first feed stream from said first separator means to said second separator means;
- a fractional distillation column means;
- means for supplying the liquid portion of said first feed stream as a second feed stream from said first separator means to said fractional distillation column means;
- means for supplying the liquid in said second separator means as a third feed stream to said fractional distillation column means;
- means for calculating a first signal representative of the predicted desired total feed flow to said fractional distillational column means required to prevent flooding of said fractional distillation column means;
- means for establishing a second signal representative of the flow rate of said second feed stream;
- means for establishing a third signal representative of the flow rate of said third feed stream;
- means for summing said second signal and said third signal to establish a fourth signal representative of the actual total feed flow rate to said fractional distillation column means;
- means for comparing said first signal and said fourth signal and for establishing a fifth signal responsive to the difference between said first signal and said fourth signal;
- means for manipulating the flow rate of said second feed stream in response to said fifth signal;
- means for establishing a sixth signal representative of the actual liquid level in said first separator means;
- means for establishing a seventh signal representative of the actual liquid level in said second separator means;
- means for comparing said sixth signal and said seventh signal and for establishing an eighth signal responsive to the difference between said sixth signal and said seventh signal;
- means for combining said fifth signal and said eighth signal to establish a ninth signal;
- means for manipulating the flow rate of said third feed stream in response to said ninth signal;
- means for calculating a tenth signal representative of the predicted desired flow rate of said first feed stream required to prevent flooding of said fractional distillational column means;
- means for calculating an eleventh signal representative of a correction factor utilized to maintain the liquid level in said first and second separators within desired limits;
- means for combining said tenth signal and said eleventh signal to establish a twelfth signal representative of a modified predicted desired flow rate of said first feed stream required to both prevent flooding of said fractional distillation column means and maintain the liquid level in said first separator means and said second separator means within desired limits;
- means for establishing a thirteenth signal representative of the actual flow rate of said first feed stream;
- means for comparing said twelfth signal and said thirteenth signal and for establishing a fourteenth signal responsive to the difference between said twelfth signal and said thirteenth signal;
- and
- means for manipulating the flow rate of said first feed stream in response to said fourteenth signal.
22 more elements
Dependencies are inferred from the claim text.