Emission monitoring system

• US 5,970,426 A
• Filed: 06/02/1997
• Issued: 10/19/1999
• Est. Priority Date: 09/22/1995
• Status: Expired due to Fees

• Current Assignee: Rosemount Analytical, Inc. (Emerson Electric Company)
• Original Assignee: Rosemount Analytical, Inc. (Emerson Electric Company)
• Inventors: Sobel, Richard A., Mandel, Stephen
• Primary Examiner(s): Barlow, John
• Assistant Examiner(s): VO, HIEN XUAN
• Application Number:
  US08/867,301
• Time in Patent Office: 869 Days
• Field of Search: 702/32, 702/22, 364/150, 364/151, 364/528.09, 701/29, 706/15, 706/16, 706/21, 706/23, 706/25
• US Class Current: 702/32
• CPC Class Codes: F23G 5/50 Control or safety arrangements
• CPC Class Codes: Y02E 20/12 Heat utilisation in combustion or incineration of waste

Abstract

A method and apparatus for providing output emission data corresponding to output emissions from a source of emissions includes a sensing emission monitoring system that senses the output emissions directly from the source of emissions and a predictive emission monitoring system that predicts the output emissions from the source of emissions. The sensing emission monitoring system provides a first set of output values indicative of the output emissions, while the predictive emission monitoring system provides a second set of output values indicative of the output emissions. The system checks the operating state of the sensing emission monitoring system and generates output emission data from the first set of output values if the sensing emission monitoring system is operable and from the second set of the output values if the sensing emission monitoring system is inoperable.

Claims

1. A method for providing output emission data corresponding to output emissions from a source of emissions operating in response to control signals from corresponding controls and having parameter sensors measuring selected operating parameters of the source of emissions and providing corresponding sensor output signals, the method comprising the steps of:

measuring the output emissions directly from the source of emissions with a sensing emission monitoring system and providing a first set of output values indicative of the output emissions;

predicting the output emissions from the source of emissions with a predictive emission monitoring system receiving the control signals and the sensor output signals, the predictive emission monitoring system providing a second set of output values indicative of the output emissions;

checking an operating state of the sensing emission monitoring system; and

generating the output emission data from the first set of output values if the sensing emission monitoring system is operable and the second set of output values if the sensing emission monitoring system is inoperable.

2. The method of claim 1 wherein the step of checking includes calibrating the sensing emission monitoring system with calibrated output emissions.

3. The method of claim 1 wherein the sensing emission monitoring system provides a status output signal indicative of an operating status of the sensing emission monitoring system, and wherein the step of checking includes monitoring the status output signal.

4. The method of claim 1 wherein the step of checking includes monitoring at least one of the first set of output values to ascertain if said at least one of the first set of output values is outside a selected range.

5. The method of claim 1 and further comprising the steps of comparing the first set of output values with the second set of output values;

and retraining the predictive emission monitoring system when the second set of output values differs from the first set of output values by a selected difference.

6. The method of claim 5 wherein at least one output value of the second set of output values includes a bias adjustment and wherein the step of comparing includes adjusting the bias adjustment if a difference between said at least one output value and a corresponding value of the first set of output values is less than the selected difference.

7. The method of claim 6 wherein the step of comparing includes adjusting the bias adjustment if the difference between said at least one output value and the corresponding value of the first set of output values is more than a second selected difference, the second selected difference being less than the first-mentioned selected difference.

8. The method of claim 1 and further comprising the steps of training the predictive emission monitoring system using a set of control signal values each having a range of values;

and storing the first set of output values and corresponding values of the control signals if at least one value of the control signals values exceeds the corresponding range of said at least one value of the control signal.

9. The method of claim 8 and wherein the step of storing includes storing the first set of output values and the corresponding values of the control signal values in a first memory location if said at least one value of the control signal values exceeds a corresponding range of said at least one value of the control signal and in a second memory location if said at least one value of the control signal values is within the corresponding range of said at least one value of the control signal.

10. An apparatus providing output emission data corresponding to output emissions from a source of emissions operating in response to control signals from corresponding controls and having parameter sensors measuring selected operating parameters of the source of emissions and providing corresponding sensor output signals, the apparatus comprising:

a sensing emission monitoring system for sensing the output emissions directly from the source of emissions and providing a first set of output values indicative of the output emissions;

a predictive emission monitoring system for predicting the output emissions from the source of emissions, the predictive emission monitoring system receiving the control signals and the sensor output signals and providing a second set of output values indicative of the output emissions; and

a computer receiving the first and second sets of output values and generating the output emission data from the first set of output values if the sensing emission monitoring system is operable and from the second set of output values if the sensing emission monitoring system is inoperable.

11. The apparatus of claim 10 wherein the sensing emission monitoring system provides a status output signal indicative of an operating status of the sensing emission monitoring system, and wherein the computer receives the status output signal.

12. The apparatus of claim 10 wherein the computer monitors at least one of the first set of output values to ascertain if said at least one of the first set of output values is outside a selected range.

13. A method for acquiring data for training a predictive emission monitoring system that generates output values indicative of output emissions from a source of emissions, the predictive emission monitoring system being trained using a training data set, the training data set including a plurality of data sets comprising at least one of values indicative of control signals from corresponding controls and parameter sensors measuring selected operating parameters of the source of emissions correlated with actual output emission values corresponding to said at least one of values indicative of control signals from corresponding controls and parameter sensors measuring selected operating parameters of the source of emissions and providing corresponding sensor output signals, the method comprising the steps of:

obtaining a new data set comprising a new actual output emission value for said at least one of values indicative of control signals from corresponding controls and parameter sensors measuring selected operating parameters of the source of emissions; and

updating the training data set with the new data set.

14. The method of claim 13 and further comprising the step of comparing the new data set with the training data set, and wherein the step of updating includes updating the training data set with the new data set if the new data set is out of a range of the training data set.

15. A method for providing output emission data corresponding to output emissions from a source of emissions operating in response to control signals from corresponding controls and having parameter sensors measuring selected operating parameters of the source of emissions and providing corresponding sensor output signals, the method comprising the steps of:

installing a sensing emission monitoring system at the source of emissions;

installing and training a predictive emission monitoring system at the source of emissions;

measuring the output emissions directly from the source of emissions during normal operation thereof with the sensing emission monitoring system and providing a first set of output values indicative of the output emissions;

predicting the output emissions from the source of emissions during normal operation thereof with the predictive emission monitoring system receiving the control signals and the sensor output signals, the predictive emission monitoring system providing a second set of output values indicative of the output emissions;

comparing periodically the first set of output values with the second set of output values during normal operation of the source of emissions; and

providing an indication to retrain the predictive emission monitoring system if a difference between any one of the second set of output values and a corresponding value of the first set of output values exceeds a selected threshold.

16. The method of claim 15 wherein at least one output value of the second set of output values includes a bias adjustment and wherein the step of comparing includes adjusting the bias adjustment if a difference between said at least one output value and a corresponding value of the first set of output values is less than the selected threshold.

17. The method of claim 15 and further comprising:

acquiring a training data set for training the predictive emission monitoring system, the training data set including a plurality of data sets comprising at least one of values indicative of control signals from corresponding controls and parameter sensors measuring selected operating parameters of the source of emissions correlated with actual output emission values corresponding to said at least one of values indicative of control signals from corresponding controls and parameter sensors measuring selected operating parameters of the source of emissions;

obtaining a new data set during normal operation of the source of emissions comprising a new actual output emission value for said at least one of values indicative of control signals from corresponding controls and parameter sensors measuring selected operating parameters of the source of emissions; and

updating the training data set with the new data set.

18. The method of claim 17 and further comprising the step of comparing the new data set with the training data set, and wherein the step of updating includes updating the training data set with the new data set if the new data set is out of a range of the training data set.

19. A method for providing output emission data corresponding to output emissions from a source of emissions operating in response to control signals from corresponding controls and having parameter sensors measuring selected operating parameters of the source of emissions and providing corresponding sensor output signals, the method comprising the steps of:

installing a sensing emission monitoring system at the source of emissions;

installing and training a predictive emission monitoring system at the source of emissions;

measuring the output emissions directly from the source of emissions during normal operation thereof with the sensing emission monitoring system and providing a first set of output values indicative of the output emissions;

predicting the output emissions from the source of emissions during normal operation thereof with the predictive emission monitoring system receiving the control signals and the sensor output signals, the predictive emission monitoring system providing a second set of output values indicative of the output emissions, wherein at least one output value of the second set of output values includes a bias adjustment;

comparing periodically the first set of output values with the second set of output values during normal operation of the source of emissions; and

adjusting the bias adjustment if a difference between said at least one output value and a corresponding value of the first set of output values is less than a selected difference.