Leslie A Dupre

US Patent:

20020017113, Feb 14, 2002

Filed:

May 29, 2001

Appl. No.:

09/865702

Inventors:

David Seiver - Sugar Land TX, US
Leslie Dupre - Baton Rouge LA, US

International Classification:

F25J003/00

US Classification:

062/656000

Abstract:

A method for automatically setting a target production level for at least one air separation unit in a network of air separation units. Each air separation unit has a plurality of field elements and at least one regulatory controller associated with one of the field elements, and has an energy usage level corresponding to a level of production. The method includes receiving a production level requirement for the network of air separation units and generating a production target level for at least one of the air separation units which minimizes and/or optimizes the sum of the ASU energy usage levels. The ASUs then can automatically ramp the plant production to the appropriate production target levels via the use of advanced process control (multivariable process controllers and/or advanced feedforward controllers), advanced regulatory control, and regulatory control means. In another embodiment, the invention is a network of air separation units, including at least two air separation units in fluid communication with a pipeline and a control system in control communication with the air separation units for automatically setting the ASU target production levels. Each air separation unit has a plurality of field elements, at least one production level and an energy usage level corresponding to the production level. The control system includes a receiver for receiving inputs from the at least two air separation units, and a supervisory controller which generates production target levels for sending to each air separation unit, the production target levels being representative of a network production target level and a network energy usage level.