Multi-dimensional portable gas chromatograph system

• US 8,114,200 B2
• Filed: 06/11/2010
• Issued: 02/14/2012
• Est. Priority Date: 05/16/2006
• Status: Active Grant

• Current Assignee: Ludlum Measurements, Inc.
• Original Assignee: VPI Engineering, Inc.
• Inventors: Alm, Sheena, Bentley, James, Blankevoort, John, Kaspersen, Mark, Lewis, Collin, Maxwell, Derek, Wunner, Ken
• Primary Examiner(s): CLEMENTE, ROBERT ARTHUR
• Application Number:
  US12/814,147
• Publication Number:
  US 20100250146A1
• Time in Patent Office: 613 Days
• Field of Search: 961/01, 961/02, 961/04, 961/05, 961/06, 95/82, 95/86, 95/87, 73/233.5, 73/233.6, 73/233.9, 73/234, 73/234.1, 73/234.2
• US Class Current: 96/101
• CPC Class Codes: G01N 2030/0095 Separation specially adapted for use outside laboratory, e.g. field sampling, portable equipments
• CPC Class Codes: G01N 2030/025 Gas chromatography
• CPC Class Codes: G01N 2030/625 by measuring reference material, e.g. carrier without sample
• CPC Class Codes: G01N 30/463 for multidimensional chromatography
• CPC Class Codes: G01N 30/66 Thermal conductivity detectors

Abstract

A portable multi-dimensional gas chromatograph, the gas chromatograph including a carrier gas container, a regulator fluidly connected to the carrier gas container, a dopant chamber containing a reference chemical, at least one pre-concentrator which is fluidly connected to the regulator and the dopant chamber, a first separation column fluidly connected to the at least one pre-concentrator, a second separation column fluidly connected to the at least one pre-concentrator, a first detector fluidly connected to the first separation column, and a second detector fluidly connected to the second separation column.

Claims

1. A portable multi-dimensional gas chromatograph, the gas chromatograph comprising:

a carrier gas container;

a regulator fluidly connected to the carrier gas container;

a dopant chamber containing a reference chemical;

at least one pre-concentrator which is fluidly connected to the regulator and the dopant chamber, a first separation column fluidly connected to the at least one pre-concentrator;

a second separation column fluidly connected to the at least one pre-concentrator;

a housing, the housing comprising an insulated valve housing configured to receive a column support, tubing that makes up the first separation column is wrapped around the column support, a column housing and a port plate fitted together;

a first detector fluidly connected to the first separation column, the first detector received in an opening defined by the insulated valve housing and the column housing,

a second detector fluidly connected to the second separation column,

wherein at least one of said first detector and said second detector is a thermal conductivity detector fluidly connected to one of said first and second separations columns, the thermal conductivity detector comprising;

a second housing having an internal gas analysis chamber, a fluid inlet passageway in communication with the gas analysis chamber, a fluid outlet passageway in communication with the gas analysis chamber, and a first bore extending through at least a portion of the housing, the first bore in fluid communication with the gas analysis chamber, the first bore offset from the fluid inlet passageway and the fluid outlet passageway.

2. The portable multi-dimensional gas chromatograph of claim 1 wherein said at least one pre-concentrator is a graphitized carbon-based molecular sieve.

3. The portable multi-dimensional gas chromatograph of claim 1 wherein said first and said second column assembly each comprise said housing, the housing further defining a first chamber, the column support, wherein the column support is ring-shaped about an axis and comprises a circumferential outer surface oriented about the axis and a plurality of axially oriented bridges, the bridges extending radially from the outer surface of the column support, and wherein the column support is positioned within the first chamber, wherein the column tubing is in contact with the plurality of bridges and is separated from the outer surface of the column support.

4. The portable multi-dimensional gas chromatograph of claim 3 wherein said first separation column and said second separation column has column tubing having a length of at least about 15 meters.

5. The portable multi-dimensional gas chromatograph of claim 1 wherein said one of said first detector or said second detector is selected from the group consisting of photoionization, atomic emission, chemiluminescence, electron-capture, flame ionization, mass spectrometer, thermal conductivity, flame photometric, infrared, Fourier Transform infrared, ultraviolet/visible absorbance, far ultraviolet absorbence, and nitrogen phosphorous.

6. The portable multi-dimensional gas chromatograph of claim 1 wherein each of said first separation column and said second separation column comprises a separate heater with separate heater control electronics in contact with each of said first separation column and said second separation column.

7. The portable multi-dimensional gas chromatograph of claim 1 wherein said portable gas chromatograph further comprises a heater with heater control electronics in contact with said at least one pre-concentrator.

8. The portable multi-dimensional gas chromatograph of claim 1 wherein said first detector has a first output signal and said second detector has a second output signal, said first output signal and said second output signal in communication with a signal processing unit.

9. The portable multi-dimensional gas chromatograph of claim 8 wherein said signal processing unit further comprises analog signal processing electronics in communication with said first detector, said second detector or both.

10. The portable multi-dimensional gas chromatograph of claim 9 wherein said signal processing unit is further in communication with a wireless radio which allows wireless communication between the central processing unit and an external computer.

11. The portable multi-dimensional gas chromatograph of claim 10 wherein said central processing unit is in communication with a display.

12. The portable multi-dimensional gas chromatograph of claim 8 wherein said signal processing unit further comprises digital signal processing electronics in communication with said analog signal processing electronics.

13. The portable multi-dimensional gas chromatograph of claim 8 wherein signal processing unit further includes a central processing unit.

14. The portable multi-dimensional gas chromatograph of claim 8 wherein said signal processing unit further includes a recognition library.

15. The portable multi-dimensional gas chromatograph of claim 1 wherein said thermal conductivity detector further comprises a thermistor, a sensor housing, a body housing, a first end plate and a second end plate.

16. The portable multi-dimensional gas chromatograph of claim 15 wherein contact pins pass through the sensor housing and are electrically attached to the thermistor and internal cavities in the sensor housing and body housing form a gas analysis chamber in which the thermistor is located.

17. The portable multi-dimensional gas chromatograph of claim 1 wherein said thermal conductivity detector further comprises a thermistor, said thermistor is a microthermistor, said microthermistor is aligned along the fluid inlet passageway.

18. The portable multi-dimensional gas chromatograph of claim 17 wherein the microthermistor comprises a glass coating.

19. The portable multi-dimensional gas chromatograph of claim 17 wherein themicrothermistor comprises two leads, the leads are formed from a material selected from the group consisting of platinum-iridium, platinum, gold and copper.

20. The portable multi-dimensional gas chromatograph of claim 19 wherein the leads comprise metallic oxide semiconductor material sintered on platinum-iridium alloy.

21. The portable multi-dimensional gas chromatograph of claim 19 wherein said insulated valve housing comprises polymethacrylimide.