Systems and methods for chemical sampling in particulate laden gaseous environments
Chemical sampling systems and methods that can inexpensively and efficiently provide accurate chemical sampling in dusty environments are disclosed. The system can include a chemical detector, an elastomeric membrane, and a support structure for the elastomeric membrane. The gas chromatograph can have a sample inlet through which chemicals from the gaseous environment can enter the gas chromatograph. The sample inlet can be covered with the elastomeric membrane, the elastomeric membrane being configured to extract chemicals from the gaseous environment while excluding dust and other particles from passing into the gas chromatograph. The support structure can be disposed between the elastomeric membrane and the sample inlet and can provide mechanical support to the elastomeric membrane.
1. A system for sampling chemicals from a gaseous environment, comprising:
a chemical detector, said detector having a sample inlet through which chemicals from the gaseous environment enter the chemical detector;
an elastomeric membrane disposed between the sample inlet and the gaseous environment, wherein the elastomeric membrane is configured to extract chemicals from the gaseous environment while excluding dust and other particles from the chemical detector;
an air inlet operably disposed between the elastomeric membrane and the gaseous environment, wherein the air inlet includes a cyclone and the elastomeric membrane is integrated in a wall of the cyclone; and
a support structure disposed between the elastomeric membrane and the sample inlet, said support structure configured to provide mechanical support to the elastomeric membrane.
2. The system of claim 1 , wherein the chemical detector is selected from the group consisting of a gas chromatograph, an ion mobility spectrometer, a mass spectrometer, a Raman spectrometer, and a point chemical detector.
3. The system of claim 1 , wherein the air inlet is configured to pass air over the elastomeric membrane to cause accumulations of dust to be removed.
4. The system of claim 1 , further comprising a wiper operable to remove dust buildup from the elastomeric membrane.
5. The system of claim 1 , wherein the elastomeric membrane has a thickness of 0.001 inches to 0.5 inches.
6. The system of claim 1 , wherein the elastomeric membrane is made from an elastomeric composition selected from the group consisting of silicone rubber, silastic, polyurethane, high density foam, and combinations thereof.
7. The system of claim 1 , wherein the elastomeric membrane is silicone rubber.
8. The system of claim 1 , wherein the support structure is made from a material selected from the group consisting of stainless steel, ceramic, plastic, and combinations thereof.
9. The system of claim 1 , wherein the support structure is configured to heat the elastomeric membrane.
10. The system of claim 9 , wherein the support structure is configured as a Peltier heater.
11. The system of claim 9 , wherein the support structure is configured to heat the elastomeric membrane to a temperature range of 35° C. to 500° C.
12. A method of measuring atmospheric chemical composition, comprising:
providing a chemical sampling device having a sample inlet through which chemicals can enter the chemical sampling device; an elastomeric membrane disposed between the sample inlet and an outer environment and an air inlet including a cyclone having the elastomeric membrane integrated into a wall thereof, and a support structure disposed between the elastomeric membrane and the sample inlet, said support structure configured to provide mechanical support to the elastomeric membrane;
contacting the elastomeric membrane with air from the environment;
regulating a passage of chemicals present in the air through the elastomeric membrane and the sample inlet and into the chemical sampling device; and
identifying the chemicals using the chemical sampling device.
13. The method of claim 12 , wherein regulating the passage of chemicals further comprises heating the elastomeric membrane to facilitate the passage of the chemicals into the chemical sampling device.
14. The method of claim 13 , wherein heating of the elastomeric membrane further comprises heating the elastomeric membrane to a temperature of 35° C. to 500° C.
15. The method of claim 12 , wherein regulating the passage of chemicals further comprises cooling the elastomeric membrane to inhibit the passage of chemicals into the gas chromatograph.
16. The method of claim 15 , wherein cooling of the elastomeric membrane further comprises cooling the elastomeric membrane to a temperature of −100° C. to 50° C.
17. The method of claim 12 , wherein contacting the elastomeric membrane with the air further comprises actively passing the air over the elastomeric membrane.
18. The method of claim 12 , further comprising passing the air through a cyclone prior to the step of contacting the elastomeric membrane.
19. A system for sampling chemicals from a gaseous environment, comprising:
a chemical sampling device, said chemical sampling device having a sample inlet through which chemicals from the gaseous environment enter the chemical sampling device;
an elastomeric membrane covering said sample inlet; and
an air inlet including a cyclone having the elastomeric membrane integrated into a wall thereof;
wherein the elastomeric membrane is configured to extract chemicals from the gaseous environment and collect dust particles from the gaseous environment and allow chemicals adsorbed in the dust particles to transfer through the elastomeric membrane and into the chemical sampling device; and
a support structure disposed between the elastomeric membrane and the sample inlet, said support structure configured to provide mechanical support to the elastomeric membrane.