Gas collection and analysis system with front-end and back-end pre-concentrators and moisture removal

1. An apparatus comprising:

a front-end pre-concentrator module including an inlet, an outlet, and at least one valve to control flow through the inlet, the outlet, or both, the front-end pre-concentrator module comprising:

a pre-concentrator having an inlet and an outlet,

a first three-way valve coupled to the inlet of the pre-concentrator and a second three-way valve coupled to the outlet of the pre-concentrator,

a trap coupled to the first three way valve,

a switch valve coupled to the second three-way valve, and

a pump coupled to the switch valve;

a back-end pre-concentrator module including an inlet, an outlet, and at least one valve to control flow through the inlet, the outlet, or both; and

a gas analysis module having an inlet and an outlet and including a gas chromatograph having an inlet and an outlet, wherein the outlet of the front-end pre-concentrator and the outlet of the back-end pre-concentrator are coupled to the inlet of the gas analysis module.

2. The apparatus of claim 1 wherein the front-end pre-concentrator module further comprises a filter coupled to the first three-way valve.

3. The apparatus of claim 2 wherein the front-end pre-concentrator module further comprises a switch valve coupled between the filter and the first three-way valve.

4. The apparatus of claim 1 wherein the back-end pre-concentrator module comprises:

a pre-concentrator having an inlet and an outlet, the inlet being coupled to the second three-way valve and to the inlet of the gas chromatograph;

a fourth three-way valve coupled to the outlet of the pre-concentrator;

a trap coupled to the fourth three-way valve;

a second pump coupled to the fourth three-way valve; and

a third three-way valve coupled to the second pump and coupled to a fluid connection between the outlet of the pre-concentrator and the fourth three-way valve.

5. The apparatus of claim 4 wherein the back-end pre-concentrator module further comprises a vent coupled to the third three-way valve.

6. The apparatus of claim 1 wherein the gas analysis module further comprises a detector coupled to the outlet of the gas chromatograph.

7. The apparatus of claim 1 wherein the gas analysis module further comprises:

a detector coupled to the outlet of the gas chromatograph;

a control circuit coupled to the gas chromatograph and to the detector, wherein the control circuit can communicate with the gas chromatograph and to the detector;

a readout circuit coupled to the detector and to the control circuit, wherein the readout circuit can communicate with the control circuit and the detector; and

a communication interface coupled to the readout circuit.

8. The apparatus of claim 7 wherein the readout circuit includes an analysis circuit and associated logic to analyze the output signals received from the detector.

9. An apparatus comprising:

a front-end pre-concentrator module including an inlet, an outlet, and at least one valve to control flow through the inlet, the outlet, or both, the front-end pre-concentrator module comprising:

a pre-concentrator having an inlet and an outlet,

a first three-way valve coupled to the inlet of the pre-concentrator and a second three-way valve coupled to the outlet of the pre-concentrator,

a trap coupled to the first three way valve,

a third three-way valve coupled to the second three-way valve, and

a pump coupled to the third three-way valve;

a back-end pre-concentrator module including an inlet, an outlet, and at least one valve to control flow through the inlet, the outlet, or both; and

a gas analysis module having an inlet and an outlet and including a gas chromatograph having an inlet and an outlet, wherein the outlet of the front-end pre-concentrator and the outlet of the back-end pre-concentrator are coupled to the inlet of the gas analysis module.

10. The apparatus of claim 9 wherein the front-end pre-concentrator module further comprises:

a first Y-splitter coupled between the first three way valve and the trap;

a second Y-splitter coupled between the second three-way valve and the third three-way valve; and

a fluid connection between the first Y-splitter and the second Y-splitter.

11. The apparatus of claim 10 , further comprising a switch valve coupled between the first Y-splitter and the second Y-splitter.

12. The apparatus of claim 9 wherein the front-end pre-concentrator module further comprises a filter coupled to the first three-way valve.

13. The apparatus of claim 12 wherein the filter is coupled to the first three-way valve by a temperature-controlled tube.

14. The apparatus of claim 9 wherein the inlet of the gas chromatograph is coupled to the second three-way valve by a third Y-splitter.

15. The apparatus of claim 14 wherein the back-end pre-concentrator module comprises:

a pre-concentrator coupled to the third Y-splitter;

a fourth three-way valve coupled to the pump and to a vent; and

a fifth three-way valve coupled to the pre-concentrator, the third three-way valve and the fourth three-way valve.

16. An apparatus comprising:

a front-end pre-concentrator module including an inlet, an outlet, and at least one valve to control flow through the inlet, the outlet, or both, the front-end pre-concentrator module comprising:

a pre-concentrator having an inlet and an outlet,

a first three-way valve coupled to the inlet of the pre-concentrator and a second three-way valve coupled to the outlet of the pre-concentrator,

a trap coupled to the first three way valve,

a fifth three-way valve coupled to the second three-way valve and to a first pump, and

an additional gas chromatograph having:

an inlet coupled to the second three-way valve, and

an outlet coupled to the inlet of the gas chromatograph, to the inlet of the back-end pre-concentrator, and to the fifth three-way valve;

a back-end pre-concentrator module including an inlet, an outlet, and at least one valve to control flow through the inlet, the outlet, or both; and

a gas analysis module having an inlet and an outlet and including a gas chromatograph having an inlet and an outlet, wherein the outlet of the front-end pre-concentrator and the outlet of the back-end pre-concentrator are coupled to the inlet of the gas analysis module.

17. The apparatus of claim 16 wherein the front-end pre-concentrator module further comprises a filter coupled to the first three-way valve.

18. The apparatus of claim 17 wherein the filter and the first three-way valve are coupled by a temperature-controlled tube.

19. The apparatus of claim 16 wherein the front-end pre-concentrator module further comprises a switch valve coupled between the filter and the first three-way valve.

20. The apparatus of claim 16 wherein the back-end pre-concentrator module comprises:

a pre-concentrator having an inlet and an outlet, the inlet being coupled to the inlet of the gas chromatograph and the outlet of the additional gas chromatograph;

a fourth three-way valve coupled to the outlet of the pre-concentrator;

a trap coupled to the fourth three-way valve;

a second pump coupled to the fourth three-way valve;

a third three-way valve coupled to the second pump and coupled to a fluid connection between the pre-concentrator and the fourth three-way valve.

21. The apparatus of claim 20 wherein the back-end pre-concentrator module further comprises a vent coupled to the third three-way valve.

22. A process comprising:

providing an apparatus including:

a front-end pre-concentrator module including an inlet, an outlet, and at least one valve to control flow through the inlet, the outlet, or both, the front-end pre-concentrator module including:

a pre-concentrator having an inlet and an outlet,

a first three-way valve coupled to the inlet of the pre-concentrator and a second three-way valve coupled to the outlet of the pre-concentrator,

a trap coupled to the first three way valve,

a second switch valve coupled to the second three-way valve, and

a pump coupled to the second switch valve;

a back-end pre-concentrator module including an inlet, an outlet, and at least one valve to control flow through the inlet, the outlet, or both; and

a gas analysis module having an inlet and an outlet and including a gas chromatograph having an inlet and an outlet, wherein the outlet of the front-end pre-concentrator and the outlet of the back-end pre-concentrator are coupled to the inlet of the gas analysis module;

configuring the at least one valve in the front-end pre-concentrator and the at least one valve in the back-end pre-concentrator to form a flow path to receive a gas sample through the front-end pre-concentrator, concentrate chemicals or volatile organic compounds carried by the gas and direct them to the gas analysis module, the back-end pre-concentrator module, or both; and

configuring the first and second three-way valves to form a flow path to receive a gas sample through the first three-way valve and concentrate chemicals or volatile organic compounds carried by the gas in the pre-concentrator.

23. The process of claim 22 , further comprising:

heating the pre-concentrator to release chemicals or volatile organic compounds (VOCs) trapped therein; and

configuring the second three-way valve to form a flow path through with the chemicals or VOCs can flow from the pre-concentrator to one or both of the back-end pre-concentrator module and the gas analysis module.

24. The process of claim 23 , further comprising directing chemicals or VOCs concentrated by the back-end pre-concentrator module into the gas analysis module.

25. The process of claim 22 , further comprising providing a back-end pre-concentrator module comprising:

a pre-concentrator having an inlet and an outlet, the inlet being coupled to the second three-way valve and to the inlet of the gas chromatograph;

a fourth three-way valve coupled to the outlet of the pre-concentrator;

a trap coupled to the fourth three-way valve;

a second pump coupled to the fourth three-way valve;

a third three-way valve coupled to the second pump and coupled to a fluid connection between the outlet of the pre-concentrator and the fourth three-way valve.

26. A process comprising:

providing an apparatus including:

a front-end pre-concentrator module including an inlet, an outlet, and at least one valve to control flow through the inlet, the outlet, or both, the front-end pre-concentrator module including:

a pre-concentrator having an inlet and an outlet,

a first three-way valve coupled to the inlet of the pre-concentrator and a second three-way valve coupled to the outlet of the pre-concentrator,

a trap coupled to the first three way valve,

a third three-way valve coupled to the second three-way valve, and

a pump coupled to the third three-way valve;

a back-end pre-concentrator module including an inlet, an outlet, and at least one valve to control flow through the inlet, the outlet, or both; and

a gas analysis module having an inlet and an outlet and including a gas chromatograph having an inlet and an outlet, wherein the outlet of the front-end pre-concentrator and the outlet of the back-end pre-concentrator are coupled to the inlet of the gas analysis module;

configuring the at least one valve in the front-end pre-concentrator and the at least one valve in the back-end pre-concentrator to form a flow path to receive a gas sample through the front-end pre-concentrator, concentrate chemicals or volatile organic compounds carried by the gas and direct them to the gas analysis module, the back-end pre-concentrator module, or both; and

configuring the first and second three-way valves to form a flow path to receive a gas sample through the first three-way valve and concentrate chemicals or volatile organic compounds carried by the gas in the pre-concentrator.

27. The process of claim 26 , further comprising:

heating the pre-concentrator to release chemicals or volatile organic compounds (VOCs) trapped therein; and

configuring the second three-way valve to form a flow path through with the chemicals or VOCs can flow from the pre-concentrator to one or both of the back-end pre-concentrator module and the gas analysis module.

28. The process of claim 27 , further comprising directing chemicals or VOCs concentrated by the back-end pre-concentrator module into the gas analysis module.

29. The process of claim 26 , further comprising providing a back-end pre-concentrator module comprising:

a pre-concentrator coupled to the third Y-splitter;

a fourth three-way valve coupled to the pump and to a vent; and

a fifth three-way valve coupled to the pre-concentrator, the third three-way valve and the fourth three-way valve.

30. A process comprising:

providing an apparatus including:

a front-end pre-concentrator module including an inlet, an outlet, and at least one valve to control flow through the inlet, the outlet, or both, the front-end pre-concentrator module including:

a pre-concentrator having an inlet and an outlet;

a first three-way valve coupled to the inlet of the pre-concentrator and a second three-way valve coupled to the outlet of the pre-concentrator;

a trap coupled to the first three way valve;

a third three-way valve coupled to the second three-way valve and to a first pump; and

an additional gas chromatograph having:

an inlet coupled to the second three-way valve, and

an outlet coupled to the inlet of the gas chromatograph, to the inlet of the back-end pre-concentrator, and to the third three-way valve;

a back-end pre-concentrator module including an inlet, an outlet, and at least one valve to control flow through the inlet, the outlet, or both; and

a gas analysis module having an inlet and an outlet and including a gas chromatograph having an inlet and an outlet, wherein the outlet of the front-end pre-concentrator and the outlet of the back-end pre-concentrator are coupled to the inlet of the gas analysis module;

configuring the at least one valve in the front-end pre-concentrator and the at least one valve in the back-end pre-concentrator to form a flow path to receive a gas sample through the front-end pre-concentrator, concentrate chemicals or volatile organic compounds carried by the gas and direct them to the gas analysis module, the back-end pre-concentrator module, or both.

31. The process of claim 30 , further comprising:

heating the pre-concentrator to release chemicals or volatile organic compounds (VOCs) trapped therein; and

configuring the second three-way valve to form a flow path through with the chemicals or VOCs can flow from the pre-concentrator to one or both of the back-end pre-concentrator module and the gas analysis module.

32. The process of claim 31 , further comprising directing chemicals or VOCs concentrated by the back-end pre-concentrator module into the gas analysis module.

33. The process of claim 30 , further comprising providing a back-end pre-concentrator module comprising:

a pre-concentrator having an inlet and an outlet, the inlet being coupled to the inlet of the gas chromatograph and the outlet of the additional gas chromatograph;

a fourth three-way valve coupled to the outlet of the pre-concentrator;

a trap coupled to the fourth three-way valve;

a second pump coupled to the fourth three-way valve;

a fifth three-way valve coupled to the second pump and coupled to a fluid connection between the pre-concentrator and the fourth three-way valve.