Measurement of charge bank level in a metallurgical furnace

Patent metadata

Field	Value
Publication number	US-9417321-B2
Application number	US-201113093939-A
Country	US
Kind code	B2
Filing date	Apr 26, 2011
Priority date	Apr 26, 2010
Publication date	Aug 16, 2016
Grant date	Aug 16, 2016

Abstract

Various systems and methods for monitoring the level of a feed material layer in a metallurgical furnace are described. At least one non-contact sensor is used to sense a distance between the feed layer and a reference position. A process controller linked to the sensor provides a control signal based upon the sensed distance. The control signal may be used to control various factors in the operation of the metallurgical furnace.

First claim

We claim:

1. A system for monitoring a level of a feed material layer contained in a metallurgical furnace, the metallurgical furnace being an electric furnace, the system comprising:
at least one non-contact sensor to sense a distance between an upper surface of the feed material layer and a reference position, the at least one sensor positioned above the feed material layer;
a process controller communicably linked to the at least one non-contact sensor to output a control signal based on the sensed distance;
a protective housing to protect each non-contact sensor;
a thermal radiation shield positioned between each non-contact sensor and the feed material layer;
a gas supply system to flush each protective housing with cooling gas; and
at least one electrode in the metallurgical furnace having one or more operating parameters controllable based on the control signal, the at least one electrode being communicably linked to the process controller,
wherein the non-contact sensor is electromagnetically insulated from electromagnetic interference present in the metallurgical furnace, and
wherein the non-contact sensor is selected to penetrate the electromagnetic interference.

2. The system of claim 1 , wherein the at least one non-contact sensor comprises:
at least one transmitter positioned above the feed material and having an unobstructed line of sight to the feed material layer contained in the furnace, the at least one transmitter configured to project an electromagnetic signal toward the upper surface of feed material layer;
at least one receiver positioned to receive a reflection of the electromagnetic signal from the upper surface of the feed material layer; and
the non-contact sensor operable to determine the sensed distance,
wherein characteristics of the electromagnetic signal are selected to penetrate the electromagnetic interference.

3. The system of claim 1 , wherein at least one sensor is fixedly mounted relative to the furnace.

4. The system of claim 1 , wherein the furnace comprises a plurality of feed ports and at least one sensor is positioned proximate to at least one of the plurality of feed ports.

5. The system of claim 1 , wherein the furnace comprises a plurality of electrode ports and at least one sensor is positioned proximate to at least one of the plurality of electrode ports.

6. The system of claim 1 , wherein the at least one sensor comprises a plurality of sensors each generating at least one corresponding sensed distance and the process controller is configured to generate the control signal based on a plurality of sensed distances.

7. The system of claim 6 , wherein the process controller is configured to process the plurality of sensed distances to provide a surface topography of a surface of the feed material layer.

8. The system of claim 7 , further comprising a display communicably linked to the controller to display at least one of any one of the plurality of sensed distances and the surface topography.

9. The system of claim 8 , wherein the display is remote from the furnace.

10. The system of claim 6 , wherein the process controller is configured to compare the surface topography to a pre-determined surface topography and to provide a surface output signal based on the comparison.

11. The system of claim 6 , wherein the process controller is configured to output a plurality of control signals, each control signal being based on a corresponding one of the plurality of sensed distances.

12. The system of claim 1 , wherein each sensor comprises a radar sensor.

13. The system of claim 1 , wherein the thermal radiation shield includes refractory cloth.

14. The system of claim 1 , wherein each protective housing comprises a Faraday cage to shield the non-contact sensor from the electromagnetic interference.

15. The system of claim 1 , wherein the thermal radiation shield comprises a removable cassette containing refractory cloth.

16. The system of claim 15 , wherein the thermal radiation shield is substantially transparent to the electromagnetic signal and the reflection.

17. The system of claim 1 , wherein each sensor is positioned above a corresponding opening in a roof of the furnace, the opening providing the unobstructed line of sight to the feed material layer.

18. The system of claim 1 , wherein the reference position is a known mounting location of the sensor.

19. The system of claim 1 , wherein the controller is operable to generate the control signal in real-time.

20. The system of claim 1 , wherein the process controller is communicably linked to a feed actuator and is configured to generate a feed control signal to automatically regulate a feed rate of the feed material based on feed control signal.

21. The system of claim 1 , wherein the process controller is communicably linked to an electrode actuator and the control signal is configured to control the one or more operating parameters of the at least one electrode by automatically moving the electrode from a first position to a second position based on the control signal.

22. The system of claim 1 , wherein the process controller is communicably linked to an electrode power supply regulator and the control signal is configured to control the one or more operating parameters of the at least one electrode by automatically regulating the power supplied to the electrode based on the control signal.

23. The system of claim 1 , wherein the at least one sensor is moveably supported to enable the at least one sensor to sense a first sensed distance when the sensor is in a first position and to sense a second sensed distance when the sensor is in a second position.

24. The system of claim 1 , wherein the at least one sensor is operable to sense a plurality of sensed distances corresponding to a plurality of locations on a surface of the feed material layer.

25. The system of claim 1 , wherein the process controller is configured to receive and process data from at least one thermal sensor.

26. The system of claim 1 , wherein the at least one sensor is positionable to sense a second sensed distance between a second material layer and the reference position.

27. The system of claim 1 , wherein the at least one sensor comprises a first sensor positioned for sensing the sensed distance and a second sensor positioned to sense a second sensed distance between a second material layer and the reference position.

28. The system of claim 2 , wherein the at least one receiver comprises at least two receivers and the at least one transmitter is communicably linked to each of the at least two receivers.

29. The system of claim 1 , wherein the one or more operating parameters of the at least one electrode in the metallurgical furnace is a parameter selected from the group consisting of electrode position and electrode power supply.

30. The system of claim 1 , wherein the non-contact sensor is selected from the group consisting of a laser sensor, an automated sounding sensor, an optical sensor, a Muon particle sensor, an acoustic sensor, a pulsed or frequency modulated electromagnetic sensor, an ultrasound sensor and a yo-yo sensor.

31. The system of claim 2 , wherein the characteristics of the electromagnetic signal selected to penetrate the electromagnetic interference are selected from the group consisting of travel

Assignees

• Sadri Afshin
• Shameli Ehsan
• Venditti Roberto
• Kepes Andrei
• Gerritsen Terry
• Southall Sean
• Uyeda Bruce
• Hatch Ltd

Inventors

• Sadri Afshin
• Shameli Ehsan
• Venditti Roberto
• Kepes Andrei
• Gerritsen Terry
• Southall Sean
• Uyeda Bruce

Classifications

• G01S7/03

  Details of HF subsystems specially adapted therefor, e.g. common to transmitter and receiver · CPC title

• F27B3/085

  Arc furnaces · CPC title

• B22D2/003

  for the level of the molten metal (B22D11/181 and B22D11/201 take precedence; level indicators in general G01F23/00) · CPC title

• F27D21/0028

  Devices for monitoring the level of the melt · CPC title

• G01F23/284

  Electromagnetic waves · CPC title