초록 ▼

An off-gas analyzer for analyzing H2O vapor, CO, O2, CO2 and/or H2 in a furnace gas stream is fluidically coupled to a gas extraction probe. The analyzer includes an optical measurement cell having multiple sampling chambers, optically coupled to a laser. The analyzer measuring cell is housed within

An off-gas analyzer for analyzing H2O vapor, CO, O2, CO2 and/or H2 in a furnace gas stream is fluidically coupled to a gas extraction probe. The analyzer includes an optical measurement cell having multiple sampling chambers, optically coupled to a laser. The analyzer measuring cell is housed within a heated cabinet having a heater operable to heat the interior thereof so as to maintain the extracted gas sample therein at a temperature about the condensation point of water. The analyzer allows for the analysis of the gas water vapour of wet off-gas samples.

대표청구항 ▼

1. An off-gas analyzer apparatus for measuring gas components of a gas sample to be analyzed, the apparatus comprising, a gas component measuring cell comprising, first and second elongated sampling chambers, said sampling chambers being in fluid communication with a gas inlet for receiving said gas

1. An off-gas analyzer apparatus for measuring gas components of a gas sample to be analyzed, the apparatus comprising, a gas component measuring cell comprising, first and second elongated sampling chambers, said sampling chambers being in fluid communication with a gas inlet for receiving said gas sample to be analyzed, said first and second sampling chambers extending from a respective first end to a second end spaced therefrom, said sampling chambers having a respective length correlated to an absorption profile of an associated target gas component of said gas sample to be analyzed,an optical head adapted for optical coupling to a coherent light source and including a plurality of emitters, said emitters being positioned to emit a coherent light beam along an associated sampling chamber,a detector assembly being positioned towards the sampling chamber second ends, the detector assembly provided for electronic coupling to a gas analyzer and including at least one detector for receiving said coherent light beams emitted from said emitters,a filter assembly for filtering particulate matter from said gas sample prior to analysis by said gas component measuring cell,a gas conduit assembly substantially providing fluid communication between a gas sample source and said filter assembly, and from said filter assembly and said gas inlet; andwherein the coherent light source comprises a plurality of tunable lasers, said lasers being provided for optical coupling to an associated said emitter for emitting said coherent light beam,a pump assembly operable to convey said gas sample from said gas sample source through said gas conduit assembly and into said measuring cell for analysis, anda cabinet, said gas component measuring cell, said pump assembly and said filter assembly being substantially housed within said cabinet, said pump assembly and said sampling chambers being selected whereby said gas sample is received in said measuring cell as a high velocity sample flow having a flow rate selected at between about 10 to 40 liters per minute. 2. The apparatus of claim 1, wherein said gas component measuring cell comprises first and second removable windows spaced towards and substantially sealing respectively each of the first and second ends of the sampling chambers. 3. The apparatus as claimed in claim 1, wherein said emitters further comprise a collimator selected to emit said coherent light beam as a collimated light beam along said associated sampling chamber, and said detector assembly further comprises a lens associated with each said sampling chamber for refocusing each said collimated light beam towards an associated said detector. 4. The apparatus as claimed in claim 1, wherein said first and second sampling chambers comprise generally axially aligned longitudinally extending cylindrical chambers, said chambers being provided in fluidic communication along substantially their entire longitudinal length, said gas inlet being fluidically coupled to said first sampling chamber adjacent to said first chamber first end, and a gas outlet being fluidically coupled to said second sampling chamber adjacent to said second chamber second end. 5. The apparatus as claimed in claim 1, wherein said gas conduit assembly comprises a heated gas conduit having a length selected at between about 2 and 15 meters. 6. The apparatus as claimed in claim 1, wherein said gas component measuring cell is provided as a modular removable unit. 7. The apparatus as claimed in claim 1, wherein said cabinet comprises a heated compartment, and a heater assembly thermally communicating with said heated compartment, said gas component measuring cell being housed substantially within an interior of said heated compartment,and wherein said heater assembly is operable to maintain said heated compartment interior at a temperature of between about 105° C. and 130° C. 8. The apparatus as claimed in claim 1, wherein said gas sample comprises an off-gas sample from a steel making furnace off gas stream, and said target gas component is selected from the group consisting of CO, CO2, H2, water vapour, and O2. 9. The apparatus as claimed in claim 1, wherein the cabinet further includes an unheated compartment, the pump assembly including a pump motor being housed substantially within an interior of the unheated compartment. 10. An off-gas analysis system for measuring gas components of a gas sample from a furnace off-gas stream, the system comprising, a gas analyzer apparatus,a processor,a coherent light source comprising a plurality of tunable diode lasers, anda gas conduit assembly for fluidically communicating said gas sample from a sampling point in said off-gas stream to said gas analyzer apparatus, the gas analyzer apparatus including, a gas component measuring cell comprising, a gas inlet fluidically communicating with said gas conduit assembly,a plurality of elongated sampling chambers, said sampling chambers being in fluid communication the gas inlet for receiving said gas sample therethrough, said sampling chambers extending from a respective end to a second end spaced therefrom, said sampling chamber having a respective length correlated to an absorption profile of an associated target gas component of said gas sample to be analyzed,an optical head being position towards the sampling chamber first ends, the optical head including a plurality of emitters, said emitters being provided for optical coupling to an associated one of said tunable diode lasers and positioned to emit coherent light beam energy therefrom substantially along an associated sampling chamber,a detector assembly electronically communicating with said processor and including a plurality of optical detectors, said detectors being positioned towards an associated sampling chamber second end for detecting and converting non-absorbed portions of associated said coherent light beam energy as electric signals,a filter assembly in fluid communication with said conduit assembly and said gas component measuring cell, the filter assembly disposed in an upstream position from said gas inlet for filtering particulate matter from said gas sample prior to analysis in said gas component measuring cell,a pump assembly operable to convey said gas sample from said sampling point through said filter assembly and into said sampling chambers for analysis,a cabinet comprising a heated compartment, and a heater assembly thermally communicating with said heated compartment,said gas component measuring cell being housed substantially within an interior of said heated compartment,and wherein said heater assembly is operable to maintain said heated compartment interior at a temperature of between about 105° C. and 140° C.,the cabinet further includes an unheated compartment, the pump assembly including a pump motor being housed substantially within an interior of the unheated compartment. 11. The system as claimed in claim 10, wherein said gas conduit assembly includes an elongated sampling probe for extracting said off-gas sample from a generally central portion of said furnace off-gas stream, and a heated conduit fluidically coupling said probe and said gas analyzer, the heated conduit operable to convey said extracted gas sample from said probe to said gas analyzer apparatus as a heated gas sample at a temperature selected at between about 80° C. and 150° C. 12. The system as claimed in claim 10, wherein said gas component measuring cell comprises first and second removable windows spaced towards each of the first and second ends of the sampling chambers. 13. The system as claimed in claim 10, wherein said emitters further comprise a collimator operable to emit said coherent light beam energy as a collimated light beam, and said detector assembly further comprises a lens associated with each said sampling chamber, said lens configured to refocus the emitted collimated light beam towards the associated optical detector. 14. The system as claimed in claim 10, wherein the plurality sampling chambers include first and second generally cylindrical chambers, said first and second cylindrical chambers being provided in fluid communication along longitudinally extending edge portions, said gas inlet being fluidically coupled to said first cylindrical chamber adjacent to said first chamber first end, and a gas outlet being fluidically coupled to said second cylindrical chamber adjacent to said second chamber second end. 15. The system as claimed in claim 10, wherein said gas component measuring cell is provided as a modular removable unit. 16. The system as claimed in claim 10, wherein said off-gas system comprises a steel making furnace off gas stream, and said gas components are selected from the group consisting of CO, CO2, H2, water vapour, and O2. 17. A furnace gas analysis and control system comprising, a plurality of gas analyzer apparatus operable to measure selected gas components of an extracted furnace off-gas sample,a system processor electronically communicating with each said gas analyzer and operable to output furnace control signals in response to the measured gas components detected thereby,a coherent light source comprising a plurality of tunable diode lasers, anda gas conduit assembly in fluid communication between a selected sampling point in said off-gas stream and an associated said gas analyzer apparatus, each said gas analyzer apparatus including, a gas component measuring cell comprising, a gas inlet and gas outlet,a plurality of elongated sampling chambers for receiving the extracted off-gas sample therein, said sampling chambers fluidically communicating with each other and said gas inlet, the sampling chambers extending respectively from a first end to a second end spaced therefrom, and having a respective length correlated to an absorption profile the selected gas component of said off-gas sample to be analyzed,an optical head being positioned towards the sampling chamber first ends, the optical head including a plurality of emitters, said emitters being optically coupled to an associated said tunable diode laser positioned to emit an associated coherent light beam therefrom along an associated sampling chamber,a detector assembly comprising an optical detector positioned towards each associated sampling chamber second end for detecting and converting non-absorbed portions of said associated coherent light beam into electric signals, anda filter assembly disposed in an upstream position from said gas inlet for filtering particulate matter from said extracted off-gas sample prior to analysis in said gas component measuring cell,a pump assembly operable to convey said off-gas samples from said selected sampling points to the gas inlet of selected said gas analyzer apparatus, anda cabinet, said gas component measuring cell, said pump assembly and said filter assembly being substantially housed within said cabinet, said pump assembly and said sampling chambers being selected whereby said gas sample is received in said measuring cell as a high velocity sample flow having a flow rate selected at between about 10 to 40 liters per minute. 18. The system as claimed in claim 17, further comprising, a switching assembly operable to selectively optically couple said lasers and the associated emitters of a selected first said analyzer apparatus and second said analyzer apparatus. 19. The system of claim 17, wherein said gas component measuring cell comprises first and second removable windows spaced towards and substantially sealing respectively each of the first and second ends of the sampling chambers, and each of the sampling chambers comprising a generally co-axially aligned cylindrical chamber,the sampling chambers being in fluid communication along longitudinally extending adjacent edge portions. 20. The system as claimed in claim 19, wherein said gas component measuring cell is provided as a replaceable modular unit, and said emitters further comprise a collimator selected to emit said coherent light beam as a collimated light beam along said associated sampling chamber, and said detector assembly further comprises a lens associated with each said sampling chamber for refocusing each said collimated light beam towards an associated said detector. 21. Use of a furnace gas analysis and control system comprising, a plurality of off-gas analyzer apparatus, each off-gas analyzer comprising: a gas component measuring cell comprising, first and second elongated sampling chambers, said sampling chambers being in fluid communication with a gas inlet for receiving a gas sample to be analyzed, said first and second sampling chambers extending from a respective first end to a second end spaced therefrom, said sampling chambers having a respective length correlated to an absorption profile of an associated target gas component of said gas sample to be analyzed,an optical head adapted for optical coupling to a coherent light source and including a plurality of emitters, said emitters being positioned to emit a coherent light beam along an associated sampling chamber,a detector assembly being positioned towards the sampling chamber second ends, the detector assembly provided for electronic coupling to a gas analyzer and including at least one detector for receiving said coherent light beams emitted from said emitters,a filter assembly for filtering particulate matter m said gas sample prior to analysis by said gas component measuring cell,a gas conduit assembly substantially providing fluid communication between a gas sample source and said filter assembly, and from said filter assembly and said gas inlet; andwherein the coherent light source comprises a plurality of tunable lasers, said lasers being provided for optical coupling to an associated said emitter for emitting said coherent light beam,pump assembly operable to convey said gas sample from said gas sample source through said filter assembly and into said measuring cell for analysis, anda cabinet, said gas component measuring cell, said pump assembly and said assembly being substantially housed within said cabinet, said pump assembly and said sampling chambers being selected whereby said gas sample is received in said measuring cell as a high velocity sample flow having a flow rate selected at between about 10 to 40 liters per minute;a system processor electronically communicating with each said off-gas analyzer apparatus and the coherent light source, wherein,the gas conduit assembly of a first said off-gas analyzer being provided in fluid communication with a first sampling location along a furnace off-gas fume duct for receiving associated extracted gas samples therefrom, andthe gas conduit assembly of a second said off-gas analyzer being provided in fluid communication with a second sampling location along the furnace off-gas fume duct for receiving associated extracted gas samples therefrom, and wherein said second sampling location is spaced from said first sampling location,and wherein in use, following the extraction and communication of the associated extracted gas sample, into the sampling chambers of the first gas analyzer, with said system processor, actuating said first off-gas analyzer to emit from said lasers said coherent light beams from said associated emitters along the associated sampling chambers, andby the detector assembly, detecting and measuring the emitted coherent light beams in the sampling chambers as an absorption profile of an associated target off-gas component selected from the group consisting of N2, CO, CO2, H2, O2 and water vapour at said first sampling locations, andfollowing the extraction and communication of the associated extracted gas samples to the sampling chambers of the second gas analyzer, with the system processor, actuating said second off-gas analyzer to emit from said lasers said coherent light beams from said associated emitters along the associated sampling chambers, andby the detector assembly, detecting and measuring the emitted coherent light beams as an absorption profile of the associated target off-gas component at said second sampling location, andcomparing the measured absorption profiles of the target off-gas components to the first and second sampling locations, and generating furnace control signals based on the comparison. 22. Use of the furnace gas analysis and control system as claimed in claim 21, wherein the system processor is operable to preferentially actuate one or more of said off-gas analyzers by increased time and/or frequency to effect a gas sample analysis which is weighted to one or more sampling locations along the furnace off-gas fume duct. 23. Use of the furnace analysis and control system as claimed in claim 21, wherein the furnace gas analysis and control system further includes an optical switching assembly operable to selectively optically couple one said laser and the optical head of the first off-gas analyzer and the optical head of the second off-gas analyzer, the system processor being operable to selectively actuate a selected one of the first and second off-gas analyzer apparatus, and operating the optical switching assembly to optically couple the one said laser to each of the first and second off-gas analyzer when selectively actuated.