Monitoring and Controlling Hydrocyclones Using Vibration Data

• US 20170239594A1
• Filed: 10/02/2015
• Published: 08/24/2017
• Est. Priority Date: 10/02/2014
• Status: Active Application

• Current Assignee: Computational Systems Incorporated (Emerson Electric Company)
• Original Assignee: Emerson Electric (US) Holding Corporation (Chile) Limitada (Emerson Electric Company)
• Inventors: BOWERS, Stewart V., BASSETT, Timothy Scott, BANERJEE, Tuhin, SCHAFFER, Michael, NOWER, Daniel
• Granted Patent: US 10,258,905 B2
• Time in Patent Office: Days
• CPC Class Codes: B01D 21/267 by using a cyclone
• CPC Class Codes: B01D 21/34 Controlling the feed distribution; Controlling the liquid level ; Control of process parameters
• CPC Class Codes: B04C 11/00 Accessories, e.g. safety or control devices, not otherwise provided for , e.g. regulators, valves in inlet or overflow ductingwith electrostatic precipitating arrangements B03C3/14
• CPC Class Codes: G01H 1/00 Measuring characteristics of vibrations in solids by using direct conduction to the detector G01H9/00, G01H11/00 take precedence

Abstract

A hydrocyclone vibration measurement system includes an upper vibration sensor attached to the overflow of a hydrocyclone and a lower vibration sensor attached to the underflow of the hydrocyclone. A vibration analysis system includes an ADC, an overall vibration value processing channel, and one or more band pass filters. The overall vibration value processing channel generates overflow and underflow scalar vibration values representing overall vibration measured at the overflow and underflow portions of the hydrocyclone. The vibration analysis system may interface with a DCS to provide control information for controlling the hydrocyclone based on the overflow and underflow scalar vibration values.

Claims

1. A hydrocyclone vibration measurement system comprising:

a set of upper vibration sensors comprising at least one vibration sensor attached to an overflow portion of each hydrocyclone in a hydrocyclone pack, the upper vibration sensors generating a plurality of analog overflow vibration signals;

a set of lower vibration sensors comprising at least one vibration sensor attached to an underflow portion of each of the hydrocyclones in the hydrocyclone pack, the lower vibration sensors generating a plurality of analog underflow vibration signals; and

a vibration analysis system including;

an analog-to-digital converter for sampling the analog overflow vibration signals and underflow vibration signals at a fixed sampling rate and converting the analog overflow and underflow vibration signals into digital overflow and underflow vibration signals; and

one or more overall vibration processing channels for processing the digital overflow and underflow vibration signals to generate overflow and underflow scalar vibration values representing overall vibration measured at the overflow and underflow portions of the hydrocyclones in the hydrocyclone pack.

2. The system of claim 1 wherein the vibration analysis system includes one or more band pass filters for band pass filtering the digital overflow and underflow vibration signals to generate band pass limited digital overflow and underflow vibration signals.

3. The system of claim 1 wherein the vibration analysis system is operable to interface with a distributed control system to provide control information to the distributed control system based at least in part on the overflow and underflow scalar vibration values.

4. The system of claim 1 wherein the upper vibration sensors are disposed such that a sensing axis of each upper vibration sensor is substantially perpendicular to a central flow axis of the hydrocyclone on which the sensor is mounted, and the lower vibration sensors are disposed such that a sensing axis of each lower vibration sensor is substantially perpendicular to the central flow axis of the hydrocyclone on which the sensor is mounted.

5. The system of claim 1 wherein the vibration analysis system includes a comparison module that compares one or more of

the overflow scalar vibration values measured during a first time period to the underflow scalar vibration values measured during the first time period,

the overflow scalar vibration values measured during the first time period to the overflow scalar vibration values measured during a second time period that is different from the first time period,

the underflow scalar vibration values measured during the first time period to the underflow scalar vibration values measured during the second time period,

the overflow scalar vibration values measured during the first time period to baseline overflow scalar vibration values measured during a time period when one or more of the hydrocyclones were operating in a normal condition, and

the underflow scalar vibration values measured during the first time period to baseline underflow scalar vibration values measured during the time period when one or more of the hydrocyclones were operating in a normal condition,

based on which the comparison module generates control information that may be used in initiating control or making decisions about control of one or more of the hydrocyclones.

6. The system of claim 5 wherein the comparison module compares the overflow scalar vibration values in a frequency range of 0 kHz to 4 kHz measured during the first time period to baseline overflow scalar vibration values in the frequency range of 0 kHz to 4 kHz measured during a time period when one or more of the hydrocyclones were operating in a normal condition.

7. The system of claim 5 wherein the comparison module generates control information for controlling operation of one or more of the hydrocyclones in the pack when energy levels of the overflow scalar vibration values in the frequency range of 0 kHz to 4 kHz measured during the first time period are higher than energy levels of the baseline overflow scalar vibration values in the frequency range of 0 kHz to 4 kHz measured during a time period when one or more of the hydrocyclones were operating in a normal condition.

8. The system of claim 7 wherein the control information comprises an alert message that informs an operator regarding a roping condition that may be occurring in underflow from one or more of the hydrocyclones.

9. The system of claim 7 wherein the control information comprises a control signal that initiates a shutdown of one or more of the hydrocyclones.

10. The system of claim 5 wherein the comparison module compares the underflow scalar vibration values in a frequency range of 0.5 kHz to 2.5 kHz measured during the first time period to baseline underflow scalar vibration values in the frequency range of 0.5 kHz to 2.5 kHz measured during a time period when one or more of the hydrocyclones were operating in a normal condition.

11. The system of claim 5 wherein the comparison module generates control information for controlling one or more of the hydrocyclones when energy levels of the underflow scalar vibration values in the frequency range of 0.5 kHz to 2.5 kHz measured during the first time period are higher than energy levels of the baseline underflow scalar vibration values in the frequency range of 0.5 kHz to 2.5 kHz measured during a time period when one or more of the hydrocyclones were operating in a normal condition.

12. The system of claim 11 wherein the control information comprises an alert message that informs an operator regarding a roping condition that may be occurring in underflow from one or more of the hydrocyclones.

13. The system of claim 11 wherein the control information comprises a control signal that initiates a shutdown of one or more of the hydrocyclones.

14. The system of claim 5 wherein the comparison module generates control information for controlling operation of one or more of the hydrocyclones when

energy levels of the underflow scalar vibration values measured during the first time period are less than energy levels of the overflow scalar vibration values measured during the first time period, or

energy levels of the underflow scalar vibration values measured during the second time period which occurs after the first time period are greater than energy levels of the overflow scalar vibration values measured during the second time period,

wherein a transition of the energy levels of the underflow scalar vibration values from less than to greater than the energy levels of the overflow scalar vibration values indicates a plugged condition of one or more of the hydrocyclones.

15. The system of claim 14 wherein the control information comprises an alert message that informs an operator regarding the plugged condition of one or more of the hydrocyclones.

16. The system of claim 14 wherein the control information comprises a control signal that initiates a shutdown of one or more of the hydrocyclones.

17. The system of claim 2 wherein the one or more band pass filters comprise:

a first band pass filter for band pass filtering the digital overflow vibration signal in a first frequency range of 0 to 4000 Hz to generate the filtered digital overflow vibration signal; and

a second band pass filter for band pass filtering the digital underflow vibration signal in a first frequency range of 500 to 2500 Hz to generate the filtered digital underflow vibration signal.

18. The system of claim 1 wherein the one or more overall vibration processing channels comprise:

a first overall vibration processing channel for calculating the overflow scalar vibration values representing overall vibration measured at the overflow portions of the hydrocyclones in the hydrocyclone pack; and

a second overall vibration processing channel for calculating the underflow scalar vibration values representing overall vibration measured at the underflow portions of the hydrocyclones in the hydrocyclone pack.

19. A method for measuring and analyzing vibration associated with a hydrocyclone, the method comprising:

(a) sensing vibration associated with an overflow portion of the hydrocyclone using an upper vibration sensor attached to the overflow portion;

(b) the upper vibration sensor generating an analog overflow vibration signal indicative of the vibration sensed in step (a);

(c) sensing vibration associated with an underflow portion of the hydrocyclone using a lower vibration sensor attached to the underflow portion;

(d) the lower vibration sensor generating an analog underflow vibration signal indicative of the vibration sensed in step (c);

(e) sampling the analog overflow vibration signal and underflow vibration signal at a fixed sampling rate and converting the analog overflow and underflow vibration signals into digital overflow and underflow vibration signals; and

(f) processing the digital overflow and underflow vibration signals to generate overflow and underflow scalar vibration values representing overall vibration measured at the overflow and underflow portions of the hydrocyclone.

20. The method of claim 19 further comprising band pass filtering the digital overflow and underflow vibration signals to generate band pass limited digital overflow and underflow vibration signals.

21. The method of claim 19 further comprising providing control information to a distributed control system based at least in part on the overflow and underflow scalar vibration values.

22. The method of claim 19 further comprising:

(g) comparing one or more of

the overflow scalar vibration values measured during a first time period to the underflow scalar vibration values measured during the first time period,

the overflow scalar vibration values measured during the first time period to the overflow scalar vibration values measured during a second time period that is different from the first time period,

the underflow scalar vibration values measured during the first time period to the underflow scalar vibration values measured during the second time period,

the overflow scalar vibration values measured during the first time period to baseline overflow scalar vibration values measured during a time period when hydrocyclone was operating in a normal condition, and

the underflow scalar vibration values measured during the first time period to baseline underflow scalar vibration values measured during the time period when hydrocyclone was operating in a normal condition; and

(h) based on the comparing of step (g), generating control information that may be used in initiating control or making decisions about control of the hydrocyclone.

23. The method of claim 22 wherein step (g) comprises comparing the overflow scalar vibration values in a frequency range of 0 kHz to 4 kHz measured during the first time period to baseline overflow scalar vibration values in the frequency range of 0 kHz to 4 kHz measured during a time period when the hydrocyclone was operating in a normal condition.

24. The method of claim 22 wherein step (h) comprises generating control information for controlling operation of the hydrocyclone when energy levels of the overflow scalar vibration values in the frequency range of 0 kHz to 4 kHz measured during the first time period are higher than energy levels of the baseline overflow scalar vibration values in the frequency range of 0 kHz to 4 kHz measured during a time period when the hydrocyclone was operating in a normal condition.

25. The method of claim 22 wherein step (h) comprises generating an alert message that informs an operator regarding a roping condition that may be occurring in underflow from the hydrocyclone.

26. The method of claim 22 wherein step (h) comprises generating a control signal that initiates a shutdown of the hydrocyclone.

27. The method of claim 22 wherein step (g) comprises comparing the underflow scalar vibration values in a frequency range of 0.5 kHz to 2.5 kHz measured during the first time period to baseline underflow scalar vibration values in the frequency range of 0.5 kHz to 2.5 kHz measured during a time period when the hydrocyclone was operating in a normal condition.

28. The method of claim 22 wherein step (h) comprises generating control information for controlling operation of the hydrocyclone when energy levels of the underflow scalar vibration values in the frequency range of 0.5 kHz to 2.5 kHz measured during the first time period are higher than energy levels of the baseline underflow scalar vibration values in the frequency range of 0.5 kHz to 2.5 kHz measured during a time period when the hydrocyclone was operating in a normal condition.

29. The method of claim 22 wherein step (h) comprises generating control information for controlling operation of the hydrocyclone when

energy levels of the underflow scalar vibration values measured during the first time period are less than energy levels of the overflow scalar vibration values measured during the first time period, and

energy levels of the underflow scalar vibration values measured during the second time period which occurs after the first time period are greater than energy levels of the overflow scalar vibration values measured during the second time period,

wherein a transition of the energy levels of the underflow scalar vibration values from less than to greater than the energy levels of the overflow scalar vibration values indicates a plugged condition of the hydrocyclone.

30. The method of claim 29 wherein step (h) comprises generating the control information comprising an alert message that informs an operator regarding the plugged condition of the hydrocyclone.

31. The method of claim 29 wherein step (h) comprises generating the control information comprising a control signal that initiates a shutdown of the hydrocyclone.