REAL TIME OPTIMIZATION OF BATCH PROCESSES

• US 20150212501A1
• Filed: 12/17/2014
• Published: 07/30/2015
• Est. Priority Date: 01/30/2014
• Status: Active Grant

• Current Assignee: ExxonMobil Research & Engineering Company (Exxon Mobil Corporation)
• Original Assignee: ExxonMobil Research & Engineering Company (Exxon Mobil Corporation)
• Inventors: BOKIS, Constantinos, GEORGIOU, Apostolos T., HANRATTY, Peter J.
• Granted Patent: US 10,133,268 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G05B 13/021 in which a variable is automatically adjusted to optimise the performance
• CPC Class Codes: G05B 23/0294 Optimizing process, e.g. process efficiency, product quality

Abstract

Systems and methods for optimizing a system operating in a first mode of operation include detecting an event associated with a cycle in a first mode of operation. When the cycle ends (i.e., when another event is detected), steady state criteria is applied to determine whether data associated with the cycle satisfies the steady state criteria. Optimization targets can be calculated based on the data associated with the cycle. Control signals including the optimization targets can be applied to a next cycle operating in the first mode of operation to improve process performance.

Claims

1. A method for optimizing a system operating in a first mode of operation, the method comprising:

detecting an event associated with a cycle operating in a first mode of operation;

determining whether data associated with the cycle satisfies steady state criteria;

generating optimization targets for the first mode of operation based on the data; and

applying control signals comprising the optimization targets, using one or more processors, for a next cycle operating in the first mode of operation.

2. The method of claim 1, wherein the event comprises a drum change event.

3. The method of claim 1, wherein the event comprises an online spalling transition event.

4. The method of claim 1, wherein determining whether the data associated with the cycle satisfies the steady state criteria comprises:

selecting an offset; and

determining whether data following the offset from the event satisfies the steady state criteria.

5. The method of claim 4, wherein the offset is selected based on a time period of transient behavior in previous cycles operating in the first mode of operation.

6. The method of claim 4, wherein the offset is about 90 minutes.

7. The method of claim 1, wherein determining whether data associated with the cycle satisfies the steady state criteria comprises:

separating the cycle into a first cycle portion and a second cycle portion;

averaging a first set of data associated with the first cycle portion;

averaging a second set of data associated with the second cycle portion; and

determining whether the average of the first set of data and the average of the second set of data are within a predetermined tolerance of an overall average.

8. The method of claim 7, wherein determining whether the data associated with the cycle satisfies the steady state criteria further comprises comparing a maximum value and a minimum value to the overall average.

9. The method of claim 1, wherein the control signals further comprise optimized values for control variables.

10. The method of claim 1, wherein the optimization targets comprise at least one of a reflux flow rate, a pumparound flow rate, an overhead temperature, and overhead product specification, and a bottom product specification.

11. The method of claim 1, further comprising:

detecting a second event associated with a second cycle operating in the first mode of operation;

determining that data associated with the second cycle satisfies the steady state criteria;

adjusting the optimization targets for the first mode of operation based on the data associated with the second cycle; and

applying second control signals comprising the adjusted optimization targets for a subsequent cycle in the first mode of operation.

12. The method of claim 1, further comprising:

detecting a second event associated with a second cycle operating in the first mode of operation;

determining that data associated with the second cycle does not satisfy the steady state criteria; and

applying the control signals comprising the optimization targets, without adjusting the optimization targets based on the data associated with the second cycle, for a subsequent cycle in the first mode of operation.

13. An apparatus for optimizing a system operating in a first mode of operation, the apparatus comprising:

a monitoring component configured to monitor the system to detect an event associated with a cycle operating in a first mode of operation;

a steady state determination component configured to determine whether data associated with the cycle satisfies steady state criteria;

an optimization target generator configured to generate optimization targets for the first mode of operation based on the data; and

a controller configured to apply control signals comprising the optimization targets for a next cycle operating in the first mode of operation.