APC process parameter estimation

• US 7,862,771 B2
• Filed: 12/03/2004
• Issued: 01/04/2011
• Est. Priority Date: 08/27/2004
• Status: Expired due to Fees

• Current Assignee: General Electric Technology GmbH (GE Aerospace)
• Original Assignee: Alstom Technology Ltd. (Alstom SA)
• Inventors: Piche, Stephen, Boyden, Scott A.
• Primary Examiner(s): WRIGHT, PATRICIA KATHRYN
• Application Number:
  US11/002,436
• Publication Number:
  US 20060045802A1
• Time in Patent Office: 2,223 Days
• Field of Search: None
• US Class Current: 422/62
• CPC Class Codes: B01D 2257/302 Sulfur oxides
• CPC Class Codes: B01D 2257/404 Nitrogen oxides other than dinitrogen oxide
• CPC Class Codes: G05B 13/027 using neural networks only
• CPC Class Codes: G05B 13/048 using a predictor
• CPC Class Codes: Y10T 436/12 Condition responsive control

Abstract

A virtual analyzer is provided to estimate either an attribute of a reactant applied during performance of, or an amount of a reactant exhausted by, a process having multiple process parameters (MPPs) that is performed to control an amount of a pollutant emitted into the air. The virtual analyzer includes an interface which receives signals corresponding to attributes of the MPPs. If the process is a wet flue gas desulfurization (WFGD) process, the signals include a signal corresponding to a measured pH level of the applied reactant. If the process is a selective catalytic reduction (SCR) process, the signals include a signal corresponding to a measured amount of the reactant exhausted by the process.

Claims

1. An article of manufacture for estimating either an attribute of a reactant applied during performance of, or an amount of a reactant exhausted by, a process having multiple process parameters (MPPs) that is performed to control an amount of a pollutant emitted into the air, comprising:

non-transitory computer readable storage media; and

logic stored on the storage media, wherein the stored logic is configured to be executable by one or more computers and thereby cause the one or more processors to operate so as to;

receive signals corresponding to attributes of the MPPs, including (i) if the process is a wet flue gas desulfurization (WFGD) process, a signal corresponding to a measured current pH level of the applied reactant, and (ii) if the process is a selective catalytic reduction (SCR) process, a signal corresponding to a measured current amount of the reactant exhausted by the process; and

estimate (i) if the process is the WFGD process, a current pH level of the applied reactant based on the attributes of the MPPs, other than the measured current pH level of the applied reactant, that correspond to the received signals, and on one of a neural network process model and a non-neural network process model that in either case represents a relationship between the pH level of the applied reactant and the attributes of the MPPs other than the measured current pH level of the applied reactant, or (ii) if the process is the SCR process, a current amount of the reactant exhausted by the process based on the attributes of the MPPs, other than the measured current amount of the reactant exhausted by the process, that correspond to the received signals and on one of a neural network process model and a non-neural network process model that in either case represents a relationship between the amount of the reactant exhausted by the process and the attributes of the MPPs other than the measured amount of the reactant exhausted by the process;

wherein execution of the stored logic by the one or more processors also thereby causes the one or more computers to operate so as to (a) compare (i) if the process is the WFGD process, the estimated pH level of the applied reactant with the measured pH level of the applied reactant corresponding to the received signal or (ii) if the process is the SCR process, the estimated amount of reactant exhausted by the process with the measured amount of reactant exhausted by the process corresponding to the received signal, and (b) determine (i) if the process is the WFGD process, the validity of the measured pH level based on the comparison, and (ii) if the process is the SCR process, the validity of the measured amount based on the comparison.

2. The article of manufacture according to claim 1, wherein:

the pH level of the applied reactant, or the amount of the reactant exhausted by the process, is estimated in real time during performance of the process; and

the estimated pH level is compared with the measured pH level of the applied reactant and the validity of the measured pH level is determined, or the estimated amount is compared with the measured amount of reactant exhausted by the process and the validity of the measured amount is determined, in real time during performance of the process.

3. The article of manufacture according to claim 1, wherein:

the attributes of the MPPs corresponding to the received signals include one or more of (i) an attribute of one of the MPPs measured during performance of the process and (ii) an attribute of one of the MPPs computed based on attributes of other of the MPPs measured during performance of the process.

4. The article of manufacture according to claim 1, wherein:

the pH level of the applied reactant or the amount of the reactant exhausted by the process, is estimated in real time during performance of the process.

5. The article of manufacture according to claim 1, wherein:

the reactant is a limestone slurry;

the process is a WFGD process which applies the limestone slurry to remove SO₂ from SO₂ laden wet flue gas, and exhausts desulfurized flue gas;

the attributes of the MPPs include an amount of SO₂ in the SO₂ laden flue gas and an amount of SO₂ in the exhausted desulfurized flue gas;

the one model represents a relationship between the pH level of the applied limestone slurry and the amount of SO₂ in the SO₂ laden flue gas and the amount of SO₂ in the exhausted desulfurized flue gas; and

the pH level of the applied limestone slurry is estimated based on the amount of SO₂ in the SO₂ laden flue gas and the amount of SO₂ in the exhausted desulfurized flue gas that correspond to the received signals, and on the one model.

6. The article of manufacture according to claim 1, wherein:

the reactant is ammonia;

the process is a SCR process which applies ammonia to remove NO_x from NO_x laden flue gas and exhausts reduced NO_x flue gas;

the attributes of the MPPs include an amount of NO_x in the NO_x laden flue gas and an amount of NO_x in the exhausted desulfurized flue gas;

the one model represents a relationship between the amount of the ammonia in the exhausted reduced NO_x flue gas and the amount of NO_x in the NO_x laden flue gas and the amount of NO_x in the exhausted reduced NO_x flue gas; and

the amount of the ammonia in the exhausted reduced NO_x flue gas is estimated based on the amount of NO_x in the NO_x laden flue gas and the amount of NO_x in the exhausted reduced NO_x flue gas that correspond to the received signals, and on the one model.

7. The article of manufacture according to claim 1, wherein:

the one network process model is a dynamic neural or non-neural network process model which represents a relationship over time between the pH level of the reactant and the applicable other attributes.