Computer apparatus and method for integration of process planning optimization and control

Abstract

A system and method, which may be implemented in a plant such as a refinery, are provided for identifying at least one mismatch between operation of at least one process unit and a scheduled target for that process unit. Production values are obtained for each process unit of interest, as are prices and scheduled targets for each process unit. A differential profit value is calculated for each process unit or the set of process units, the differential profit value representing a difference in profit based on the scheduled target and the production value for the profit units. The differential profit value can be indicative of the mismatch. Remedial action can then be taken to alter a scheduled constraint of one or more process units, or an operational constraint of one or more process units.

1 . A method, comprising:
 obtaining at least one production value for each process unit of a set of process units;   obtaining a price and scheduled target for each process unit of the set of process units;   calculating at least one differential profit value for the set of process units, the differential profit value comprising a difference between profit based on the price and the scheduled target obtained for each process unit, and profit based on the price and production value for each process unit; and   identifying, from the at least one differential profit value, at least one mismatch between operation of at least one process unit of the set of process units and the scheduled target for the same at least one process unit.   
     
     
         2 . The method of  claim 1 , wherein the set of process units comprises at least one process unit in a selected refinery subprocess or circuit. 
     
     
         3 . The method of  claim 1 , wherein the set of process units comprises a plurality of process units in a refinery. 
     
     
         4 . The method of  claim 1 , further comprising testing each production value for validity according to specified limits prior to calculating the differential profit value. 
     
     
         5 . The method of  claim 4 , further comprising testing each production value to determine if the associated process unit is operating in a steady state. 
     
     
         6 . The method of  claim 1 , wherein calculating the at least one differential profit value comprises calculating a differential profit value for each individual process unit of the set of process units, the differential profit value for the individual process unit comprising a difference between profit based on the scheduled price and the scheduled target obtained for the process unit and the profit based on the production value for the same process unit. 
     
     
         7 . The method of  claim 6 , wherein obtaining the at least one production value, obtaining the price and scheduled target for each of the at least one process unit, and calculating the at least one differential profit value are carried out periodically to provide a historical set of differential profit values, and identifying the at least one mismatch comprises identifying the at least one mismatch from the historical set of differential profit values. 
     
     
         8 . The method of  claim 1 , further comprising displaying at least a subset of the historical set of differential profit values. 
     
     
         9 . The method of  claim 1 , wherein identifying the at least one mismatch comprises determining that one or more of the at least one differential profit value exceeds a corresponding limit. 
     
     
         10 . The method of  claim 1 , wherein each scheduled target for each process unit of the set of process units is associated with at least one scheduled constraint, and operation of each process unit of the set of process units is associated with at least one operational constraint, the method further comprising, for the at least one process unit for which a mismatch was identified:
 altering one or more of the at least one scheduled constraint associated with the at least one process unit; or   altering one or more of the at least one operational constraint associated with the at least one process unit.   
     
     
         11 . The method of  claim 10 , wherein the at least one scheduled constraint or the at least one operational constraint comprises one or more of a quality target, boiling points, percent content, octane number, stream temperature, reactor temperature, production stream volume, and production stream quality. 
     
     
         12 . A system for implementation in a plant comprising a plurality of process units, the system comprising:
 a differential profit calculation module configured to calculate at least one differential profit value for a set of process units of the plurality of process units, the differential profit value comprising a difference between profit based on a price and a scheduled target obtained for each process unit of the set of process units, and profit based on a price and a production value for each said process unit; and   a rationalization module configured to identify at least one mismatch between operation of at least one process unit of the set of process units and the scheduled target for the same at least one process unit from the at least one differential profit value.   
     
     
         13 . The system of  claim 12 , wherein the set of process units comprises at least one process unit in a selected subprocess or circuit of the plant. 
     
     
         14 . The system of  claim 12 , wherein the set of process units comprises a plurality of process units in a refinery. 
     
     
         15 . The system of  claim 12 , wherein the differential profit calculation module is configured to calculate the at least one differential profit value by calculating a differential profit value for each individual process unit of the set of process units, the differential profit value for the individual process unit comprising a difference between profit based on the scheduled price and the scheduled target obtained for the process unit and the profit based on the production value for the same process unit. 
     
     
         16 . The system of  claim 15 , wherein the differential profit calculation module carries out the calculating of the at least one differential profit value periodically to provide a historical set of differential profit values, the production value, price and scheduled target for each said process unit being obtained periodically, such that the at least one mismatch is identifiable from the historical set of differential profit values. 
     
     
         17 . The system of  claim 16 , further comprising a display unit for displaying at least a subset of the historical set of differential profit values. 
     
     
         18 . The system of  claim 12 , wherein the at least one mismatch is identified by determining that one or more of the at least one differential profit value exceeds a corresponding limit. 
     
     
         19 . A non-transitory computer-readable medium bearing code which, when executed by one or more processors of a computing system, causes the system to implement the method of:
 obtaining at least one production value for each process unit of a set of process units;   obtaining a price and scheduled target for each process unit of the set of process units;   calculating at least one differential profit value for the set of process units, the differential profit value comprising a difference between profit based on the price and the scheduled target obtained for each process unit, and profit based on the price and production value for each process unit; and   identifying, from the at least one differential profit value, at least one mismatch between operation of at least one process unit of the set of process units and the scheduled target for the same at least one process unit.   
     
     
         20 . The computer-readable medium of  claim 19 , wherein obtaining the at least one production value, obtaining the price and scheduled target for each of the at least one process unit, and calculating the at least one differential profit value are carried out periodically to provide a historical set of differential profit values, and identifying the at least one mismatch comprises identifying the at least one mismatch from the historical set of differential profit values.