System for a non-invasive online discrete measurement of phase levels in converters or pyrometallurgical furnaces

• US 6,836,734 B2
• Filed: 05/13/2002
• Issued: 12/28/2004
• Est. Priority Date: 05/13/2002
• Status: Expired due to Fees

• Current Assignee: Escanaba Holdings Incorporated, Saarland Corporation
• Original Assignee: Escanaba Holdings Incorporated
• Inventors: Rojas, Luis Paredes, Garreton, Alfredo Zolezzi
• Primary Examiner(s): Bui, Bryan
• Application Number:
  US10/144,908
• Publication Number:
  US 20030212501A1
• Time in Patent Office: 960 Days
• Field of Search: 702/31, 702/32, 702/33, 702/39, 702/48, 702/72, 702/104-105, 755/51, 755/52, 755/55, 755/59, 266/47, 266/78, 266/81, 266/87
• US Class Current: 702/33
• CPC Class Codes: G01N 2291/0252 Melting, molten solids
• CPC Class Codes: G01N 2291/0421 Longitudinal waves
• CPC Class Codes: G01N 29/11 by measuring attenuation of acoustic waves
• CPC Class Codes: G01N 29/228 related to high temperature conditions

Abstract

The present invention describes non-invasive online system for discrete measurements of phase levels in a converter or pyrometallurgical furnace in smelting and conversion processes, applying mechanical waves generated by a transducer placed transversally to an air blowing tuyere. Multiple transducers are placed in the direction of the cross axis or longitudinal axis of the phases plane and facing the different limiting zones between the different phases present inside the converter or pyrometallurgical furnace. A mechanical waves sensor or detector that receives the signal (echo pulses) reflected by the different limiting zones so as to determine the amplitude of the reflected signal that has a characteristic and different level for each phase, correlate the amplitude and determine the limiting zone of the phases that face the transducers.

Claims

1. A system arranged to be operable with a furnace having mixtures of materials exhibiting different phases, the system comprising:

a blowing tuyere generating an airflow, the tuyere having a furnace duct for transmitting the airflow to the furnace;

an electric signal generator for generating an electrical signal;

at least one transducer converting the electrical signal into mechanical waves, the mechanical waves travelling in the furnace duct together with the airflow in a wave direction which is transversal to the airflow direction along the furnace duct, the mechanical waves being transmitted to the furnace and being reflected by the materials according to their different phases to produce one or more reflected signals;

at least one sensor detecting the one or more reflected signals and generating a corresponding one or more detected signal; and

a first processing element measuring the amplitude of the one or more detected signal to determine the phase of the mixtures of materials producing the one or more reflected signals.

2. The system of claim 1, further comprising a second processing element correlating amplitudes of different detected signals, to determine a relative position of the different phases producing the different reflected signals.

3. The system of claim 1, further comprising:

at least one amplifier, amplifying the one or more detected signal to form one or more amplified detected signals;

an analog/digital interface digitizing the one or more amplified detected signals to form one or more digitized signals; and

a data acquisition circuit acquiring the one or more digitized signals to form acquired data, the acquired data being processed by the first processing element.

4. The system of claim 1, further comprising

a memory for storing values of the detected signals;

and

a display for showing the values.

5. The system of claim 1, wherein the sensor is placed beside or integrated with the transducer.

6. The system of claim 1, wherein the tuyere further comprises an entry duct.

7. The system of claim 6, wherein the entry duct is placed at a 180°

angle with the furnace duct.

8. The system of claim 1, further comprising coupling means connecting the electric signal generator and the transducer with the furnace.

9. The system of claim 1, wherein the furnace is a converter.

10. The system of claim 9, wherein the converter is a Teniente Converter (CT).

11. The system of claim 1, wherein the mixtures comprise a metal bath, a slag and gases.

12. A method for determining phases exhibited by mixtures of materials in a furnace, the method comprising:

transmitting an airflow to the furnace in a duct along a first direction;

generating an electrical signal;

converting the electrical signal into mechanical waves;

transmitting the mechanical waves in the duct together with the airflow along a second direction transversal to the first direction to the furnace, the mechanical waves being transmitted to the furnace and being reflected by the material according to their different phases to produce one or more reflected signals;

detecting the one or more reflected signals and generating a corresponding one or more detected signal;

measuring the amplitude of the one or more detected signal to determine the phase of the mixtures of material producing the one or more reflected signal.

13. The method of claim 12, further comprising:

correlating amplitudes of different detected signals, to determine a relative position of the different phases producing the different reflected signals.

14. The method of claim 12, further comprising:

associating detecting the one or more reflected signal with a level; and

associating the level with each determined phase of the materials producing the one or more reflected signal, to determine the position of the each determined phase.

15. The method of claim 12, wherein said mechanical waves are sonic waves.

16. The method of claim 12, wherein said mechanical waves are ultrasonic waves.

17. The method of claim 12, wherein said mechanical waves are infrasonic waves.

18. The method of claim 12, wherein the furnace is a converter.

19. The method of claim 18, wherein the converter is a Teniente Converter (CT).

20. The method of claim 12, wherein the phases are a metal bath, a slag and gases.