System, Method, and Program Product for Targeting and Identification of Optimal Process Variables in Constrained Energy Recovery Systems

• US 20100070258A1
• Filed: 10/08/2009
• Published: 03/18/2010
• Est. Priority Date: 06/23/2006
• Status: Active Grant

• Current Assignee: Saudi Arabian Oil Company (Government of Saudi Arabia)
• Original Assignee: Saudi Arabian Oil Company (Government of Saudi Arabia)
• Inventors: Noureldin, Mahmoud Bahy
• Granted Patent: US 7,729,809 B2
• Time in Patent Office: Days
• US Class Current: 703/18
• CPC Class Codes: F01K 13/02 Controlling, e.g. stopping or starting
• CPC Class Codes: G05B 13/021 in which a variable is automatically adjusted to optimise the performance

Abstract

Systems, methods, and program product to calculate global energy utility targets and to model and determine an optimal solution for a non-thermodynamically constrained process or cluster of processes subject to non-thermodynamic constraints under all possible process changes and streams specific minimum temperature approaches, are provided. An exemplary system can utilize thermodynamic constraints exhibited in stream-specific minimum temperature approach values ΔT_minⁱ as optimization parameters, in addition to other process conditions degrees of freedom including the addition of new waste heat carrier streams to target for minimizing energy consumption of the non-thermodynamic constrained waste heat recovery problem and to identify the optimal operating conditions that result in desired minimum energy consumption subject to the non-thermodynamic constraints.

Claims

1. A system to model the energy consumption of a non-thermodynamically constrained waste heat recovery process, the non-thermodynamically constrained process using a plurality of resource streams including at least one non-thermodynamically constrained process stream, the system comprising:

an energy utility consumption modeling computer including a processor and memory coupled to the processor;

energy utility consumption modeling program product to target and optimize non-thermodynamically constrained waste heat recovery for the non-thermodynamically constrained process, the program product stored in the memory of the energy utility consumption modeling computer and including instructions that when executed by the energy utility modeling computer, cause the computer to perform the operations of;

receiving a first plurality of sets of values each separately defining a potential range of attribute values for an attribute of one of a plurality of hot process streams and a second plurality of sets of values each separately defining a potential range of attribute values of an attribute of one of a plurality of cold process streams;

receiving a constrained stream list comprising an identification of at least one non-thermodynamically constrained process stream constrained from matching at least one other process stream due to a non-thermodynamic constraint defining a forbidden match;

assigning a set of a plurality of stream-specific minimum temperature approach values to a corresponding plurality of hot process streams;

decreasing a value of one of the plurality of minimum temperature approach values in the set of a plurality of stream-specific minimum temperature approach values assigned to the plurality of hot process streams, the value of the one of the plurality of minimum temperature approach values being assigned to a corresponding one of the plurality of hot process streams;

determining a plurality of temperature step intervals responsive to the potential range of attribute values for the plurality of hot process streams, the potential range of attribute values for the plurality of cold process streams, and the assigned set of the plurality of stream-specific minimum temperature approach values, each temperature step interval having an input interval indicating heat extracted collectively from the plurality of hot process streams, an output interval indicating heat collectively applied to the plurality of cold process streams, and an output interval indicating surplus heat available for a next of the plurality of temperature step intervals;

determining a global heating energy utility interval for exchangeable energy for the non-thermodynamically constrained process using the plurality of temperature step intervals;

determining a total global heating energy utility interval for the non-thermodynamically constrained process responsive to determining the global heating energy utility interval;

determining a global cooling energy utility interval for exchangeable energy for the non-thermodynamically constrained process responsive to determining the global heating energy utility interval for exchangeable energy;

determining a total global cooling energy utility interval for the non-thermodynamically constrained process responsive to determining the global cooling energy utility interval for exchangeable energy;

performing each of the operations of assigning a set of a plurality of stream-specific minimum temperature approach values, decreasing a value of one of the plurality of minimum temperature approach values assigned to a corresponding one of the plurality of hot process streams, determining a plurality of temperature step intervals, determining a global heating energy utility interval for exchangeable energy, determining a total global heating energy utility interval, determining a global cooling energy utility interval for exchangeable energy, and determining a total global cooling energy utility interval, for each other of the plurality of hot process streams to thereby form a plurality of different sets of minimum temperature approach values and a corresponding plurality of global minimum heating and global minimum cooling energy utility values;

determining a set of minimum temperature approach values of the plurality of different sets of minimum temperature approach values resulting in a maximum decrease in the total global minimum heating energy utility value defining a determined optimal set of minimum approach temperature values, the total global minimum cooling energy utility value, or the total global minimum heating energy utility value and total global minimum cooling energy utility value, associated therewith defining a desired one or more optimal global minimum energy values; and

determining optimal process conditions that render the desired one or more optimal global minimum energy values responsive to the determined optimal set of minimum approach temperature values.

2. A system as defined in claim 1, wherein the plurality of hot process streams include at least one existing hot process stream to be cooled and the plurality of cold process streams include at least one existing cold process stream to be heated to define a plurality of existing process streams, and wherein the operation of determining optimal process conditions that render the desired one or more optimal global minimum energy values, includes:

determining an optimal supply temperature, an optimal target temperature, and an optimal flowrate for each of the plurality of existing process streams.

3. A system as defined in claim 2, wherein the energy utility consumption modeling program product further includes instructions to perform the operations of:

performing one or more of the following;

creating a new hot process stream to be cooled and creating a new cold process stream to be heated, defining one or more newly created process streams; and

determining optimal process conditions for each of the one or more newly created process streams, to include determining an optimal supply temperature, an optimal target temperature, and an optimal flowrate for each of the one or more newly created process streams.

4. A system as defined in claim 1,

wherein the energy utility consumption modeling program product further includes instructions to perform the operation of determining stream-by-stream for each of the plurality of temperature step intervals, a load value of non-exchangeable energy to be obtained from at least one external hot utility for the respective temperature step interval and each preceding temperature step interval to thereby determine a total of non-exchangeable energy to be obtained from the at least one external hot utility;

and

wherein the operation of determining the total global heating energy utility interval is performed by adding the global heating energy utility interval for exchangeable energy for the non-thermodynamically constrained process and the total of non-exchangeable energy to be obtained from at least one external hot utility required for the plurality of temperature step intervals.

5. A system as defined in claim 4, wherein the energy utility consumption modeling program product further includes instructions to perform the operations of:

determining a symmetric image of the global heating energy utility interval for exchangeable energy responsive to determining the global heating energy utility interval for exchangeable energy;

applying the symmetric image to the plurality of temperature step intervals to thereby determine the global cooling energy utility interval for exchangeable energy for the non-thermodynamically constrained process; and

determining the global cooling energy utility interval for exchangeable energy for the non-thermodynamically constrained process responsive to applying the symmetric image to the plurality of temperature step intervals.

6. A system as defined in claim 5,

wherein the energy utility consumption modeling program product further includes instructions to perform the operation of determining stream-by-stream for each separate one of the first plurality of temperature step intervals, a load value of non-exchangeable energy to be obtained from at least one external cold utility for the respective temperature step interval and each following temperature step interval to thereby determine a total of non-exchangeable energy to be obtained from the at least one external cold utility;

and

wherein the operation of determining the total global cooling energy utility interval is performed by adding the optimal global cooling energy utility interval for exchangeable energy for the non-thermodynamically constrained process and the total of non-exchangeable energy to be obtained from at least one external cold utility required for the plurality of temperature step intervals.

7. A system as defined in claim 1,

wherein the plurality of sets of minimum temperature approach values is a first plurality of different sets of minimum temperature approach values;

wherein the plurality of global minimum heating and global minimum cooling energy utility values is a first plurality of global minimum heating and global minimum cooling energy utility values; and

wherein the energy utility consumption modeling program product further includes instructions to perform the operations of;

assigning each of the plurality of minimum temperature approach values of the set of minimum temperature approach values determined to result in a maximum decrease in one or more of the global energy utility values as an upper minimum temperature approach value limit for each corresponding one of the plurality of hot streams to define an upper base minimum temperature approach value limit set for the plurality of hot streams,

performing each of the operations of decreasing a value of one of the plurality of minimum temperature approach value assigned to one of the plurality of hot process streams, determining a plurality of temperature step intervals, determining a global heating energy utility interval for exchangeable energy, determining an total global heating energy utility interval, and determining a total global cooling energy utility interval, for each of the plurality of hot process streams using the upper base minimum temperature approach value limit set to thereby form a second plurality of different sets of minimum temperature approach values and a corresponding second plurality of global minimum heating and global minimum cooling energy utility values, and

determining a set of minimum temperature approach values of the second plurality of different sets of minimum temperature approach values resulting in a maximum decrease in the total global minimum heating energy utility value, the total global minimum cooling energy utility value, or the total global minimum heating energy utility value and total global minimum cooling energy utility value, associated therewith.

8. A system as defined in claim 1,

wherein the input indicating heat extracted collectively from the plurality of hot process streams includes a pair of inputs defining a high-end and a low-end value of the range of values indicating heat extracted collectively from the plurality of hot process streams;

and

wherein a first value for the one of the plurality of stream-specific minimum temperature approach values is set to a user defined highest value for all hot process streams to establish a global maximum energy target values for the constrained process.

9. A system as defined in claim 1,

wherein the operation of receiving a first plurality of sets of values each separately defining a potential range of attribute values for at least one of the plurality of hot process streams includes receiving a potential range of attribute values for at least one dummy heat carrier resource stream having a type different than that of the at least one non-thermodynamically constrained process stream and the at least one other process stream;

wherein the operation of determining a first plurality of temperature step intervals is further responsive to the potential range of attribute values for the at least one dummy heat carrier stream; and

wherein the energy utility consumption modeling program product further includes instructions to perform the operation of determining an optimal value of a target temperature and the heat capacity flow rate of the at least one dummy heat carrier stream.

10. A system as defined in claim 1,

wherein the operation of receiving a first plurality of sets of values each separately defining a potential range of attribute values for at least one of the plurality of hot process streams includes receiving a range of attribute values for a potential heat capacity flow rate for a dummy heat carrier stream;

wherein the operation of determining a plurality of temperature step intervals is further responsive to the range of attribute values for the dummy heat carrier stream; and

wherein the energy utility consumption modeling program product further includes instructions to perform the operation of determining an optimal value of the target temperature and the heat capacity flow rate of the dummy heat carrier stream.

11. A system to model the energy consumption of a non-thermodynamically constrained waste heat recovery process, the non-thermodynamically constrained process using a plurality of process streams including at least one non-thermodynamically constrained process stream, the system comprising:

an energy utility consumption modeling computer including a processor and memory coupled to the processor;

energy utility consumption modeling program product to target and optimize non-thermodynamically constrained waste heat recovery for the non-thermodynamically constrained process, the program product stored in the memory of the energy utility consumption modeling computer and including instructions that when executed by the energy utility modeling computer, cause the computer to perform the operations of;

receiving a first plurality of sets of range attribute values each separately defining a potential range of attribute values for an attribute of one of a plurality of hot process streams and a second plurality of sets of range attribute values each separately defining a potential range of attribute values of an attribute of one of a plurality of cold process streams, and indicia of the non-thermodynamically constrained process stream collectively defining input data, the first and the second plurality of sets of range attribute values collectively including at least one set of a range of attribute values for at least one attribute of the non-thermodynamically constrained process stream constrained from matching at least one other process stream due to a non-thermodynamic constraint,

determining a global minimum energy utility value for exchangeable energy for the non-thermodynamically constrained process for each of a plurality of potential combinations of a plurality of stream-specific minimum temperature approach values assigned to each of the plurality of hot process streams responsive to the input data, the global minimum energy utility for exchangeable energy comprising one of the following;

optimal global minimum heating energy value for exchangeable energy and optimal global minimum cooling energy value for exchangeable energy, a number of the potential combinations of stream-specific minimum temperature approach values being at least that of a sum of a number of the plurality of hot streams and a number of the plurality of cold streams,

determining a total of non-exchangeable energy to be obtained from at least one external utility for the non-thermodynamically constrained process for each of the plurality of potential combinations of a plurality of stream-specific minimum temperature approach values assigned to each of the plurality of hot process streams responsive to the input data, the total of non-exchangeable energy to be obtained from at least one external utility comprising one of the following;

total of non-exchangeable heating energy to be obtained from at least one external hot utility and total of non-exchangeable cooling energy to be obtained from at least one external cold utility,

determining an optimal total energy consumption value for the non-thermodynamically constrained process responsive to the determined global minimum energy utility value for the non-thermodynamically constrained process and the total of non-exchangeable energy to be obtained from the at least one external utility, for each of the plurality of potential combinations of the plurality of stream-specific minimum temperature approach values, and

determining optimal process conditions that render the optimal total energy consumption value responsive to the determined optimal total energy consumption value.

12. A system as defined in claim 11, wherein the plurality of hot process streams include at least one existing hot process stream to be cooled and the plurality of cold process streams include at least one existing cold process stream to be heated to define a plurality of existing process streams, and wherein the operation of determining optimal process conditions that render the optimal total energy consumption value includes:

determining an optimal supply temperature, an optimal target temperature, and an optimal flowrate for each of the plurality of existing process streams.

13. A system as defined in claim 12, wherein the energy utility consumption modeling program product further includes instructions to perform the operations of:

performing one or more of the following;

creating a new hot process stream to be cooled and creating a new cold process stream to be heated, defining a corresponding one or more newly created process streams; and

determining optimal process conditions for each of the one or more newly created process streams, to include determining an optimal supply temperature, an optimal target temperature, and an optimal flowrate for each of the one or more newly created process streams.

14. A system as defined in claim 11, wherein the energy utility consumption modeling program product further includes instructions to perform the operations of:

assigning a set of stream-specific minimum temperature approach values for each of the plurality of hot process streams, the set of steam-specific minimum temperature approach values indicating the plurality of stream-specific minimum temperature approach values between each respective one of the hot streams and the plurality of cold process streams;

receiving a desired utility heating or cooling energy utility target as an energy objective;

collapsing a process conditions interval for process conditions for one of the plurality of hot process streams to render a discrete boundary value for the one of the plurality of hot process streams, the process conditions of the other of the plurality of hot process streams remaining in the form of intervals;

decreasing a minimum temperature approach value of one of the plurality of hot streams by one degree;

determining an effect of the decrease in the minimum temperature approach value on the desired utility target;

repeating the operations of decreasing the minimum temperature approach value and determining the effect of the decrease to thereby determine the optimal minimum temperature approach value for the one of the plurality of hot streams; and

performing the operations of collapsing a process conditions interval, decreasing a minimum temperature approach value, determining the effect of the decrease, and repeating the operations of decreasing a minimum temperature approach value and determining the effect of the decrease for each other of the plurality of hot streams to thereby determine the optimal minimum temperature approach value for each of the plurality of hot process streams.

15. Energy utility consumption modeling program product to target and optimize non-thermodynamically constrained waste heat recovery for a non-thermodynamically constrained process, the non-thermodynamically constrained process using a plurality of resource streams including at least one non-thermodynamically constrained process stream, the program product comprising a set of instructions stored in a tangible computer readable medium, that when executed by a computer, cause the computer to perform the operations of:

determining for each of a plurality of temperature step intervals for each separate one of a plurality of different sets of minimum temperature approach values assigned to a plurality of hot process streams, a load value of exchangeable energy to be obtained from at least one process stream for each respective temperature step interval responsive to at least one set of a range of attribute values for a non-thermodynamically constrained process stream, at least one set of a range of attribute values for a not non-thermodynamically constrained process stream, and indicia of at least one non-thermodynamic constraint collectively defining input data to thereby determine a global minimum energy utility value for each of the plurality of different sets of minimum temperature approach values;

determining an optimal global minimum energy utility value for exchangeable energy for the non-thermodynamically constrained process responsive to the global minimum energy utility values determined for each of the plurality of different sets of minimum temperature approach values, the optimal global minimum energy utility for exchangeable energy comprising one of the following;

an optimal global minimum heating energy value for exchangeable energy and an optimal global minimum cooling energy value for exchangeable energy;

determining for each of the plurality of temperature step intervals for each of the plurality of different sets of minimum temperature approach values, a load value of non-exchangeable energy to be obtained from the at least one external utility for the respective temperature step interval to thereby determine a total of non-exchangeable energy to be obtained from the at least one external utility for the non-thermodynamically constrained process for each of the plurality of different sets of minimum temperature approach values, the respective total of non-exchangeable energy to be obtained from at least one external utility comprising one of the following;

total of non-exchangeable heating energy to be obtained from at least one external hot utility and total of non-exchangeable cooling energy to be obtained from at least one external cold utility;

determining an optimal total energy consumption value for the non-thermodynamically constrained process responsive to the determined optimal global minimum energy utility value for the non-thermodynamically constrained process and the determined total of non-exchangeable energy associated therewith; and

determining optimal process conditions that render the optimal total energy consumption value responsive to the determined optimal total energy consumption value.

16. Program product as defined in claim 15, wherein the plurality of resource streams include at least one existing hot process stream to be cooled and at least one existing cold process stream to be heated to define a plurality of existing process streams, and wherein the operation of determining optimal process conditions that render the optimal total energy consumption value includes:

determining an optimal supply temperature, an optimal target temperature, and an optimal flowrate for each of the plurality of existing process streams.

17. Program product as defined in claim 16, wherein the energy utility consumption modeling program product further includes instructions to perform the operations of:

performing one or more of the following;

creating a new hot process stream to be cooled and creating a new cold process stream to be heated defining one or more newly created process streams; and

determining optimal process conditions for each of the one or more newly created process streams, to include determining an optimal supply temperature, an optimal target temperature, and an optimal flowrate for each of the one or more newly created process streams.

18. Program product as defined in claim 15,

wherein the determined optimal global minimum energy utility value for exchangeable energy for the non-thermodynamically constrained process comprises the optimal global minimum heating energy value for exchangeable energy for the non-thermodynamically constrained process;

wherein the determined total of non-exchangeable energy to be obtained from the at least one external utility comprises a total of non-exchangeable heating energy to be obtained from at least one external hot utility associated with the respective global minimum heating energy value for exchangeable energy for the non-thermodynamically constrained process;

wherein the optimal total energy consumption value comprises an optimal total global minimum heating energy utility value for the non-thermodynamically constrained process; and

wherein the optimal total global minimum heating energy utility value for the non-thermodynamically constrained process includes a sum of the optimal global minimum heating energy value for exchangeable energy for the non-thermodynamically constrained process and the total of non-exchangeable heating energy to be obtained from the at least one external hot utility associated therewith.

19. Program product as defined in claim 15, wherein the operations further comprise:

determining stream-by-stream for each separate one of the plurality of temperature step intervals for each separate one of the plurality of different sets of minimum temperature approach values assigned to the plurality of hot process streams, a load value of non-exchangeable energy to be obtained from the at least one external hot utility for the respective interval and each preceding interval to thereby determine the total of non-exchangeable heating energy to be obtained from the at least one external hot utility.

20. Program product as defined in claim 15,

wherein the determined optimal global minimum energy utility value for exchangeable energy for the non-thermodynamically constrained process comprises the optimal global minimum cooling energy value for exchangeable energy for the non-thermodynamically constrained process;

wherein the determined total of non-exchangeable energy to be obtained from the at least one external utility comprises a total of non-exchangeable cooling energy to be obtained from at least one external cold utility associated with the respective global minimum cooling energy value for exchangeable energy for the non-thermodynamically constrained process;

wherein the optimal total energy consumption value comprises an optimal total global minimum cooling energy utility value for the non-thermodynamically constrained process; and

wherein the optimal total global minimum cooling energy utility value for the non-thermodynamically constrained process includes a sum of the optimal global minimum cooling energy value for exchangeable energy for the non-thermodynamically constrained process and the total non-exchangeable cooling energy to be obtained from the at least one external cold utility associated therewith.

21. Program product as defined in claim 20, wherein the operations further comprise:

determining stream-by-stream for each separate one of the plurality of temperature step intervals for each separate one of the plurality of different sets of minimum temperature approach values assigned to the plurality of hot process streams, a load value of non-exchangeable energy to be obtained from at least one external cold utility for the respective interval and each following interval to thereby determine the total non-exchangeable energy to be obtained from the at least one external cold utility.

22. Program product as defined in claim 15, wherein the operations further comprise:

assigning a different set of stream-specific minimum temperature approach values for each of the plurality of hot process streams, each set of steam-specific minimum temperature approach values indicating the plurality of stream-specific minimum temperature approach values between each respective one of the hot process streams and a plurality of cold process streams;

receiving a selected utility heating or cooling energy utility target as an energy objective;

determining a global minimum energy utility value for exchangeable energy for the non-thermodynamically constrained process for each of the plurality of different sets of minimum temperature approach values;

collapsing a process conditions interval for process conditions for one of the plurality of hot process streams to render a discrete boundary value for the one of the plurality of hot process streams, the process conditions of the other of the plurality of hot process streams remaining in the form of intervals;

decreasing a minimum temperature approach value of one of the plurality of hot streams by one degree;

determining an effect of the decrease in the minimum temperature approach value on the utility target;

repeating the operations of decreasing the minimum temperature approach value and determining the effect of the decrease to determine the optimal minimum temperature approach value for the one of the plurality of hot streams; and

performing the operations of collapsing a process conditions interval, decreasing a minimum temperature approach value, determining the effect of the decrease, and repeating the operations of decreasing a minimum temperature approach value and determining the effect of the decrease for each other of the plurality of hot streams to thereby determine the optimal minimum temperature approach value for each of the plurality of hot process streams.

23. Program product as defined in claim 15, wherein the operations further comprise

receiving the at least one set of a range of attribute values for at least one attribute of the at least one non-thermodynamically constrained process streams;

receiving the at least one set of a range of attribute values for at least one attribute of at least one not non-thermodynamically constrained process stream; and

receiving a stream list comprising an identification of the non-thermodynamically constrained process stream constrained from matching at least one other process stream due to a non-thermodynamic constraint.

24. Program product as defined in claim 23, wherein the operations further comprise:

receiving at least one set of a range of attribute values for at least one dummy heat carrier resource stream having a type different than that of the at least one non-thermodynamically constrained process stream and the at least one other process stream, the at least one dummy heat carrier resource stream representing at least one potential additional resource stream that could be added to the non-thermodynamically constrained process with minimal capital cost;

recalculating the optimal total energy consumption value for the non-thermodynamically constrained process responsive to the received at least one set of a range of attribute values for the at least one non-thermodynamically constrained process stream and the at least one not non-thermodynamically constrained process stream, the received stream list, and the at least one set of a range of attribute values for the at least one dummy heat carrier stream; and

wherein the operation of determining a load value of exchangeable energy for each of a plurality of temperature step intervals for each separate one of a plurality of different sets of minimum temperature approach values is further responsive to the range of attribute values for the at least one dummy heat carrier stream.

25. Program product as defined in claim 15, wherein the operations further comprise:

receiving at least one set of a range of attribute values for at least one dummy heat carrier stream representing at least one potential additional resource stream that could be added to the non-thermodynamically constrained process with minimal capital cost;

recalculating the optimal total energy consumption value for the non-thermodynamically constrained process responsive to the received at least one set of a range of attribute values for the at least one non-thermodynamically constrained process stream and the at least one not non-thermodynamically constrained process stream, the received stream list, and the at least one set of a range of attribute values for the at least one dummy heat carrier stream; and

wherein the operation of determining a load value of exchangeable energy for each of a plurality of temperature step intervals for each separate one of a plurality of different sets of minimum temperature approach values is further responsive to the range of attribute values for the at least one dummy heat carrier stream.

26. Program product as defined in claim 15, wherein the operations further comprise:

receiving at least one set of a range of attribute values for a dummy heat carrier stream representing a potential additional resource stream that could be added to the non-thermodynamically constrained process with minimal capital cost; and

wherein the operation of determining optimal process conditions that render the optimal total energy consumption value further includes the operation of determining an optimal target temperature and heat capacity flow rate of the dummy heat carrier stream.

27. Energy utility consumption modeling program product to target and optimize non-thermodynamically constrained waste heat recovery for a non-thermodynamically constrained process, the non-thermodynamically constrained process using a plurality of process streams including at least one non-thermodynamically constrained process stream, the program product comprising a set of instructions stored in a tangible computer readable medium, that when executed by a computer, cause the computer to perform the operations of:

receiving at least one set of a range of attribute values for at least one attribute of the non-thermodynamically constrained process stream constrained from matching at least one other process stream due to a non-thermodynamic constraint, at least one set of a range of attribute values for at least one attribute of a not non-thermodynamically constrained process stream, and indicia of the non-thermodynamically constrained process stream collectively defining input data;

determining a global minimum energy utility value for exchangeable energy for the non-thermodynamically constrained process for each separate one of a plurality of potential combinations of a plurality of stream-specific minimum temperature approach values responsive to the input data;

determining an optimal global minimum energy utility value for exchangeable energy for the non-thermodynamically constrained process responsive to the global minimum energy utility value for each of the plurality of potential combinations of the plurality of stream-specific minimum temperature approach values, the optimal global minimum energy utility for exchangeable energy comprising one of the following;

an optimal global minimum heating energy value for exchangeable energy and an optimal global minimum cooling energy value for exchangeable energy;

determining a total of non-exchangeable energy to be obtained from at least one external utility for the non-thermodynamically constrained process for each of the plurality of potential combinations of the plurality of stream-specific minimum temperature approach values responsive to the input data, the total of non-exchangeable energy to be obtained from at least one external utility comprising one of the following;

a total of non-exchangeable heating energy to be obtained from at least one external hot utility and a total of non-exchangeable cooling energy to be obtained from at least one external cold utility;

determining an optimal total energy consumption value for the non-thermodynamically constrained process responsive to the determined optimal global minimum energy utility value for the non-thermodynamically constrained process and the determined total of non-exchangeable energy associated therewith; and

determining optimal process conditions that render the optimal total energy consumption value responsive to the determined optimal total energy consumption value.

28. Program product as defined in claim 27, wherein the plurality of process streams include at least one existing hot process stream to be cooled and at least one existing cold process stream to be heated to define a plurality of existing process streams, and wherein the operation of determining optimal process conditions that render the optimal total energy consumption value, includes:

determining an optimal supply temperature, an optimal target temperature, and an optimal flowrate for each of the plurality of existing process streams.

29. Program product as defined in claim 28, wherein the energy utility consumption modeling program product further includes instructions to perform the operations of:

performing one or more of the following;

creating a new hot process stream to be cooled and creating a new cold process stream to be heated defining one or more newly created process streams; and

determining optimal process conditions for each of the one or more newly created process streams, to include determining an optimal supply temperature, an optimal target temperature, and an optimal flowrate for each of the one or more newly created process streams.

30. Program product as defined in claim 27,

wherein the input data further comprises at least one set of a range of attribute values for at least one dummy heat carrier resource stream having a type different than that of the non-thermodynamically constrained process stream, the not non-thermodynamically constrained process stream, and the at least one other process stream, the at least one dummy heat carrier resource stream representing at least one potential additional resource stream that could be added to the non-thermodynamically constrained process with minimal capital cost;

and

wherein the operation of determining a global minimum energy utility value for exchangeable energy for the non-thermodynamically constrained process for each of the plurality of potential combinations of the plurality of stream-specific minimum temperature approach values is further responsive to the range of attribute values for the at least one dummy heat

carrier stream.

31. Program product as defined in claim 30, wherein the operations further comprise:

determining for each of a plurality of temperature step intervals for each separate one of the plurality of potential combinations of the plurality of stream-specific minimum temperature approach values, a load value of exchangeable energy to be obtained from at least one process stream for each respective temperature step interval responsive to the input data.

32. Program product as defined in claim 31,

wherein the determined optimal global minimum energy utility value for exchangeable energy for the non-thermodynamically constrained process comprises the optimal global minimum heating energy value for exchangeable energy for the non-thermodynamically constrained process;

wherein the determined total of non-exchangeable energy to be obtained from the at least one external utility comprises total of non-exchangeable heating energy to be obtained from at least one external hot utility associated with the respective global minimum heating energy value for exchangeable energy for the non-thermodynamically constrained process;

wherein the optimal total energy consumption value comprises an optimal total global minimum heating energy utility value for the non-thermodynamically constrained process;

wherein the optimal total global minimum heating energy utility value for the non-thermodynamically constrained process includes a sum of the optimal global minimum heating energy value for exchangeable energy for the non-thermodynamically constrained process and the total of non-exchangeable heating energy to be obtained from the at least one external hot utility associated therewith; and

wherein the operations further comprise determining stream-by-stream for each separate one of the plurality of temperature step intervals for each separate one of the plurality of potential combinations of the plurality of stream-specific minimum temperature approach values a load value of non-exchangeable energy to be obtained from the at least one external hot utility for the respective interval and each preceding interval to thereby determine the total of non-exchangeable heating energy to be obtained from the at least one external hot utility.

33. Program product as defined in claim 31,

wherein the determined optimal global minimum energy utility value for exchangeable energy for the non-thermodynamically constrained process comprises the optimal global minimum cooling energy value for exchangeable energy for the non-thermodynamically constrained process;

wherein the determined total of non-exchangeable energy to be obtained from the at least one external utility comprises total of non-exchangeable cooling energy to be obtained from at least one external cold utility associated with the respective global minimum cooling energy value for exchangeable energy for the non-thermodynamically constrained process;

wherein the optimal total energy consumption value comprises an optimal total global minimum cooling energy utility value for the non-thermodynamically constrained process;

wherein the optimal total global minimum cooling energy utility value for the non-thermodynamically constrained process includes a sum of the optimal global minimum cooling energy value for exchangeable energy for the non-thermodynamically constrained process and the total non-exchangeable cooling energy to be obtained from the at least one external cold utility associated therewith; and

wherein the operations further comprise determining stream-by-stream for each separate one of the plurality of temperature step intervals for each separate one of the plurality of potential combinations of the plurality of stream-specific minimum temperature approach values, a load value of non-exchangeable energy to be obtained from at least one external cold utility for the respective interval and each following interval to thereby determine the total non-exchangeable energy to be obtained from the at least one external cold utility.

34. Program product as defined in claim 27, wherein the operations further comprise:

receiving at least one set of a range of attribute values for a dummy heat carrier stream representing a potential additional resource stream that could be added to the non-thermodynamically constrained process with minimal capital cost; and

wherein the operation of determining optimal process conditions that render the optimal total energy consumption value further includes the operation of determining an optimal target temperature and heat capacity flow rate of the dummy heat carrier stream.

35. Program product as defined in claim 27, wherein the plurality of process streams includes a plurality of hot process streams and a plurality of cold process streams, and wherein the operations further comprise:

assigning a different set of stream-specific minimum temperature approach values for each of the plurality of hot process streams, each set of steam-specific minimum temperature approach values indicating the plurality of stream-specific minimum temperature approach values between each respective one of the hot process streams and the plurality of cold process streams;

receiving a selected utility heating or cooling energy utility target as an energy objective;

determining a global minimum energy utility value for exchangeable energy for the non-thermodynamically constrained process for each of the plurality of different sets of minimum temperature approach values;

collapsing a process conditions interval for process conditions for one of the plurality of hot process streams to render a discrete boundary value for the one of the plurality of hot process streams, the process conditions of the other of the plurality of hot process streams remaining in the form of intervals;

decreasing a minimum temperature approach value of one of the plurality of hot streams by one degree;

determining an effect of the decrease in minimum temperature approach value on the utility target;

repeating the steps of decreasing the minimum temperature approach value and determining the effect of the decrease to determine the optimal minimum temperature approach value for the one of the plurality of hot streams; and

performing the steps of collapsing a process conditions interval, decreasing a minimum temperature approach value, determining the effect of the decrease, and repeating the steps of decreasing a minimum temperature approach value and determining the effect of the decrease for each other of the plurality of hot streams to thereby determine the optimal minimum temperature approach value for each of the plurality of hot process streams.

36. A computer implemented method of modeling energy consumption of a non-thermodynamically constrained waste heat recovery process, the constrained process using a plurality of resource streams including at least one non-thermodynamically constrained process stream, the method comprising the steps of:

determining for each of a plurality of temperature step intervals for each separate one of a plurality of different sets of minimum temperature approach values assigned to a plurality of hot process streams, a load value of exchangeable energy to be obtained from at least one process stream for each respective temperature step interval responsive to at least one set of a range of attribute values for a non-thermodynamically constrained process stream, at least one set of a range of attribute values for a not non-thermodynamically constrained process stream, and indicia of at least one non-thermodynamic constraint collectively defining input data to thereby determine a global minimum energy utility value for each of the plurality of different sets of minimum temperature approach values;

determining an optimal global minimum energy utility value for exchangeable energy for the non-thermodynamically constrained process responsive to the global minimum energy utility values determined for each of the plurality of different sets of minimum temperature approach values, the optimal global minimum energy utility for exchangeable energy comprising one of the following;

an optimal global minimum heating energy value for exchangeable energy and an optimal global minimum cooling energy value for exchangeable energy;

determining for each of the plurality of temperature step intervals for each of the plurality of different sets of minimum temperature approach values, a load value of non-exchangeable energy to be obtained from the at least one external utility for the respective temperature step interval to thereby determine a total of non-exchangeable energy to be obtained from the at least one external utility for the non-thermodynamically constrained process for each of the plurality of different sets of minimum temperature approach values, the respective total of non-exchangeable energy to be obtained from at least one external utility comprising one of the following;

total of non-exchangeable heating energy to be obtained from at least one external hot utility and total of non-exchangeable cooling energy to be obtained from at least one external cold utility;

determining an optimal total energy consumption value for the non-thermodynamically constrained process responsive to the determined optimal global minimum energy utility value for the non-thermodynamically constrained process and the determined total of non-exchangeable energy associated therewith; and

determining optimal process conditions that render the optimal total energy consumption value responsive to the determined optimal total energy consumption value.

37. A method as defined in claim 36, wherein the plurality of resource streams include at least one existing hot process stream to be cooled and at least one existing cold process stream to be heated to define a plurality of existing process streams, and wherein the step of determining optimal process conditions that render the optimal total energy consumption value, includes the step of:

determining an optimal supply temperature, an optimal target temperature, and an optimal flowrate for each of the plurality of existing process streams.

38. A method as defined in claim 37, further comprising the steps of:

performing one or more of the following;

creating a new hot process stream to be cooled and creating a new cold process stream to be heated defining one or more newly created process streams; and

determining optimal process conditions for each of the one or more newly created process streams, to include determining an optimal supply temperature, an optimal target temperature, and an optimal flowrate for each of the one or more newly created process streams.

39. A method as defined in claim 36,

wherein the determined optimal global minimum energy utility value for exchangeable energy for the non-thermodynamically constrained process comprises the optimal global minimum heating energy value for exchangeable energy for the non-thermodynamically constrained process;

wherein the determined total of non-exchangeable energy to be obtained from the at least one external utility comprises a total of non-exchangeable heating energy to be obtained from at least one external hot utility associated with the respective global minimum heating energy value for exchangeable energy for the non-thermodynamically constrained process;

wherein the optimal total energy consumption value comprises an optimal total global minimum heating energy utility value for the non-thermodynamically constrained process; and

wherein the optimal total global minimum heating energy utility value for the non-thermodynamically constrained process includes a sum of the optimal global minimum heating energy value for exchangeable energy for the non-thermodynamically constrained process and the total of non-exchangeable heating energy to be obtained from the at least one external hot utility associated therewith.

40. A method as defined in claim 36, further comprising the step of:

determining stream-by-stream for each separate one of the plurality of temperature step intervals for each separate one of the plurality of different sets of minimum temperature approach values assigned to the plurality of hot process streams, a load value of non-exchangeable energy to be obtained from the at least one external hot utility for the respective interval and each preceding interval to thereby determine the total of non-exchangeable heating energy to be obtained from the at least one external hot utility.

41. A method as defined in claim 36,

wherein the determined optimal global minimum energy utility value for exchangeable energy for the non-thermodynamically constrained process comprises the optimal global minimum cooling energy value for exchangeable energy for the non-thermodynamically constrained process;

wherein the determined total of non-exchangeable energy to be obtained from the at least one external utility comprises a total of non-exchangeable cooling energy to be obtained from at least one external cold utility associated with the respective global minimum cooling energy value for exchangeable energy for the non-thermodynamically constrained process;

wherein the optimal total energy consumption value comprises an optimal total global minimum cooling energy utility value for the non-thermodynamically constrained process; and

wherein the optimal total global minimum cooling energy utility value for the non-thermodynamically constrained process includes a sum of the optimal global minimum cooling energy value for exchangeable energy for the non-thermodynamically constrained process and the total non-exchangeable cooling energy to be obtained from the at least one external cold utility associated therewith.

42. A method as defined in claim 41, further comprising the step of:

determining stream-by-stream for each separate one of the plurality of temperature step intervals for each separate one of the plurality of different sets of minimum temperature approach values assigned to the plurality of hot process streams, a load value of non-exchangeable energy to be obtained from at least one external cold utility for the respective interval and each following interval to thereby determine the total non-exchangeable energy to be obtained from the at least one external cold utility.

43. A method as defined in claim 36, wherein the plurality of resource streams includes the plurality of hot process streams and a plurality of cold process streams, the method further comprising the steps of:

assigning a different set of stream-specific minimum temperature approach values for each of the plurality of hot process streams, each set of steam-specific minimum temperature approach values indicating the plurality of stream-specific minimum temperature approach values between each respective one of the hot process streams and the plurality of cold process streams;

receiving a selected utility heating or cooling energy utility target as an energy objective;

determining a global minimum energy utility value for exchangeable energy for the non-thermodynamically constrained process for each of the plurality of different sets of minimum temperature approach values;

collapsing a process conditions interval for process conditions for one of the plurality of hot process streams to render a discrete boundary value for the one of the plurality of hot process streams, the process conditions of the other of the plurality of hot process streams remaining in the form of intervals;

decreasing a minimum temperature approach value of one of the plurality of hot streams by one degree;

determining an effect of the decrease in the minimum temperature approach value on the utility target;

repeating the steps of decreasing the minimum temperature approach value and determining the effect of the decrease to determine the optimal minimum temperature approach value for the one of the plurality of hot streams; and

performing the steps of collapsing a process conditions interval, decreasing a minimum temperature approach value, determining the effect of the decrease, and repeating the steps of decreasing a minimum temperature approach value and determining the effect of the decrease for each other of the plurality of hot streams to thereby determine the optimal minimum temperature approach value for each of the plurality of hot process streams.

44. A method as defined in claim 36, further comprising the steps of:

receiving the at least one set of a range of attribute values for at least one attribute of the at least one non-thermodynamically constrained process streams;

receiving the at least one set of a range of attribute values for at least one attribute of at least one not non-thermodynamically constrained process stream; and

receiving a stream list comprising an identification of the non-thermodynamically constrained process stream constrained from matching at least one other process stream due to a non-thermodynamic constraint.

45. A method as defined in claim 44, further comprising the steps of:

receiving at least one set of a range of attribute values for at least one dummy heat carrier stream representing a potential additional resource stream that could be added to the non-thermodynamically constrained process with minimal capital cost;

recalculating the optimal total energy consumption value for the non-thermodynamically constrained process responsive to the received at least one set of a range of attribute values for the at least one non-thermodynamically constrained process stream and the at least one not non-thermodynamically constrained process stream, the received stream list, and the at least one set of a range of attribute values for the at least one dummy heat carrier stream; and

wherein the step of determining a load value of exchangeable energy for each of a plurality of temperature step intervals for each separate one of a plurality of different sets of minimum temperature approach values is further responsive to the range of attribute values for the at least one dummy heat carrier stream.

46. A method as defined in claim 36, further comprising the step of:

receiving at least one set of a range of attribute values for a dummy heat carrier stream representing a potential additional resource stream that could be added to the non-thermodynamically constrained process with minimal capital cost; and

wherein the step of determining optimal process conditions that render the optimal total energy consumption value further includes the step of determining an optimal target temperature and heat capacity flow rate of the dummy heat carrier stream.

50. A method as defined in claim 36, further comprising the step of:

receiving at least one set of a range of attribute values for a dummy heat carrier stream representing a potential additional resource stream that could be added to the non-thermodynamically constrained process with minimal capital cost; and

wherein the step of determining optimal process conditions that render the optimal total energy consumption value further includes the step of determining an optimal target temperature and heat capacity flow rate of the dummy heat carrier stream.

47. A computer implemented method of modeling energy consumption of a non-thermodynamically constrained waste heat recovery process, the non-thermodynamically constrained process using a plurality of resource streams including at least one non-thermodynamically constrained process stream, the method comprising the steps of:

receiving at least one set of a range of attribute values for at least one attribute of the non-thermodynamically constrained process stream constrained from matching at least one other process stream due to a non-thermodynamic constraint, at least one set of a range of attribute values for at least one attribute of a not non-thermodynamically constrained process stream, and indicia of the non-thermodynamically constrained process stream collectively defining input data;

determining a global minimum energy utility value for exchangeable energy for the non-thermodynamically constrained process for each separate one of a plurality of potential combinations of a plurality of stream-specific minimum temperature approach values responsive to the input data;

determining an optimal global minimum energy utility value for exchangeable energy for the non-thermodynamically constrained process responsive to the global minimum energy utility value for each of the plurality of potential combinations of the plurality of stream-specific minimum temperature approach values, the optimal global minimum energy utility for exchangeable energy comprising one of the following;

an optimal global minimum heating energy value for exchangeable energy and an optimal global minimum cooling energy value for exchangeable energy;

determining a total of non-exchangeable energy to be obtained from at least one external utility for the non-thermodynamically constrained process for each of the plurality of potential combinations of the plurality of stream-specific minimum temperature approach values, responsive to the input data, the total of non-exchangeable energy to be obtained from at least one external utility comprising one of the following;

total of non-exchangeable heating energy to be obtained from at least one external hot utility and total of non-exchangeable cooling energy to be obtained from at least one external cold utility;

determining an optimal total energy consumption value for the non-thermodynamically constrained process responsive to the determined optimal global minimum energy utility value for the non-thermodynamically constrained process and the determined total of non-exchangeable energy associated therewith; and

determining optimal process conditions that render the optimal total energy consumption value responsive to the determined optimal total energy consumption value.

48. A method as defined in claim 47, wherein the plurality of resource streams include at least one existing hot process stream to be cooled and at least one existing cold process stream to be heated to define a plurality of existing process streams, and wherein the step of determining optimal process conditions that render the optimal total energy consumption value, includes the steps of:

determining an optimal supply temperature, an optimal target temperature, and an optimal flowrate for each of the plurality of existing process streams.

49. A method as defined in claim 48, further comprising the steps of:

performing one or more of the following;

creating a new hot process stream to be cooled and creating a new cold process stream to be heated defining one or more newly created process streams; and

determining optimal process conditions for each of the one or more newly created process streams, to include determining an optimal supply temperature, an optimal target temperature, and an optimal flowrate for each of the one or more newly created process streams.

51. A method as defined in claim 47,

wherein the input data further comprises at least one set of a range of attribute values for at least one dummy heat carrier resource stream having a type different than that of the non-thermodynamically constrained process stream, the not non-thermodynamically constrained process stream, and the at least one other process stream, the at least one dummy heat carrier resource stream representing at least one potential additional resource stream that could be added to the non-thermodynamically constrained process with minimal capital cost;

and

wherein the step of determining a global minimum energy utility value for exchangeable energy for the non-thermodynamically constrained process for each of the plurality of potential combinations of the plurality of stream-specific minimum temperature approach values is further responsive to the range of attribute values for the at least one dummy heat carrier stream.

52. A method as defined in claim 51, further comprising the step of:

determining for each of a plurality of temperature step intervals for each separate one of the plurality of potential combinations of the plurality of stream-specific minimum temperature approach values, a load value of exchangeable energy to be obtained from at least one process stream for each respective temperature step interval responsive to the input data.

53. A method as defined in claim 52,

wherein the determined optimal global minimum energy utility value for exchangeable energy for the non-thermodynamically constrained process comprises the optimal global minimum heating energy value for exchangeable energy for the non-thermodynamically constrained process;

wherein the determined total of non-exchangeable energy to be obtained from the at least one external utility comprises total of non-exchangeable heating energy to be obtained from at least one external hot utility associated with the respective global minimum heating energy value for exchangeable energy for the non-thermodynamically constrained process;

wherein the optimal total energy consumption value comprises an optimal total global minimum heating energy utility value for the non-thermodynamically constrained process;

wherein the optimal total global minimum heating energy utility value for the non-thermodynamically constrained process includes a sum of the optimal global minimum heating energy value for exchangeable energy for the non-thermodynamically constrained process and the total of non-exchangeable heating energy to be obtained from the at least one external hot utility associated therewith; and

wherein the steps further comprise determining stream-by-stream for each separate one of the plurality of temperature step intervals for each separate one of the plurality of potential combinations of the plurality of stream-specific minimum temperature approach values, a load value of non-exchangeable energy to be obtained from the at least one external hot utility for the respective interval and each preceding interval to thereby determine the total of non-exchangeable heating energy to be obtained from the at least one external hot utility.

54. A method as defined in claim 52,

wherein the determined optimal global minimum energy utility value for exchangeable energy for the non-thermodynamically constrained process comprises the optimal global minimum cooling energy value for exchangeable energy for the non-thermodynamically constrained process;

wherein the determined total of non-exchangeable energy to be obtained from the at least one external utility comprises total of non-exchangeable cooling energy to be obtained from at least one external cold utility associated with the respective global minimum cooling energy value for exchangeable energy for the non-thermodynamically constrained process;

wherein the optimal total energy consumption value comprises an optimal total global minimum cooling energy utility value for the non-thermodynamically constrained process;

wherein the optimal total global minimum cooling energy utility value for the non-thermodynamically constrained process includes a sum of the optimal global minimum cooling energy value for exchangeable energy for the non-thermodynamically constrained process and the total non-exchangeable cooling energy to be obtained from the at least one external cold utility associated therewith; and

wherein the method further comprises the step of determining stream-by-stream for each separate one of the plurality of temperature step intervals for each separate one of the plurality of potential combinations of the plurality of stream-specific minimum temperature approach values, a load value of non-exchangeable energy to be obtained from at least one external cold utility for the respective interval and each following interval to thereby determine the total non-exchangeable energy to be obtained from the at least one external cold utility.

55. A method as defined in claim 47, wherein the plurality of resource streams includes a plurality of hot process streams and a plurality of cold process streams, the method further comprising the steps of:

assigning a different set of stream-specific minimum temperature approach values for each of the plurality of hot process streams, each set of steam-specific minimum temperature approach values indicating the plurality of stream-specific minimum temperature approach values between each respective one of the hot process streams and the plurality of cold process streams;

receiving a selected utility heating or cooling energy utility target as an energy objective;

determining a global minimum energy utility value for exchangeable energy for the non-thermodynamically constrained process for each of the plurality of different sets of minimum temperature approach values;

collapsing a process conditions interval for process conditions for one of the plurality of hot process streams to render a discrete boundary value for the one of the plurality of hot process streams, the process conditions of the other of the plurality of hot process streams remaining in the form of intervals;

decreasing a minimum temperature approach value of one of the plurality of hot streams by one degree;

determining an effect of the decrease in minimum temperature approach value on the utility target;

repeating the steps of decreasing the minimum temperature approach value and determining the effect of the decrease to determine the optimal minimum temperature approach value for the one of the plurality of hot streams; and

performing the steps of collapsing a process conditions interval, decreasing a minimum temperature approach value, determining the effect of the decrease, and repeating the steps of decreasing a minimum temperature approach value and determining the effect of the decrease for each other of the plurality of hot streams to thereby determine the optimal minimum temperature approach value for each of the plurality of hot process streams.