Low Pressure Biogas Sample Takeoff and Conditioning System

• US 20150362468A1
• Filed: 06/16/2014
• Published: 12/17/2015
• Est. Priority Date: 06/16/2014
• Status: Active Grant

• Current Assignee: Mustang Sampling, LLC
• Original Assignee: Mustang Sampling, LLC
• Inventors: Gerhold, Walter F.
• Granted Patent: US 9,535,045 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01N 33/0011 Sample conditioning preparing specimens for investigation G01N1/28
• CPC Class Codes: G01N 33/0014 by eliminating a gas by a chemical reaction G01N33/0013; a chemical reaction taking place or a gas being eliminated in one or more analysing channels G01N33/0024
• CPC Class Codes: G01N 33/0016 by regulating a physical variable, e.g. pressure or temperature
• CPC Class Codes: G01N 33/004 CO or CO2
• CPC Class Codes: G01N 33/0044 Sulphides, e.g. H2S
• CPC Class Codes: G01N 33/0047 Organic compounds
• CPC Class Codes: G01N 33/0054 Ammonia
• CPC Class Codes: G01N 33/006 Avoiding interference of water vapour with the gas to be measured
• CPC Class Codes: G01N 33/225 Gaseous fuels, e.g. natural gas
• CPC Class Codes: Y02A 50/20 Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
• CPC Class Codes: Y02E 50/30 Fuel from waste, e.g. synthetic alcohol or diesel

Abstract

A temperature and pressure regulating biogas sample extraction system and method for providing a conditioned biogas sample for constituent analysis.

Claims

1. A system for conditioning and analyzing a low pressure biogas pipeline stream where the biogas contains one or more contaminants selected from the group consisting of H₂O, CO₂, H₂S, NH₃, C₂H₆, siloxanes, VOC, and O₂ intermixed with CH₄, said system, comprising:

a) at least a first gas pipeline takeoff probe for extracting a biogas sample, a heated probe housing, a biogas communication line limiting dew point dropout of the biogas sample conveying the heated biogas sample to a solenoid controlled valve switch and into a sample analyzer cabinet;

b) a gas dryer unit for receiving the extracted biogas sample;

c) a pump and a pressure regulator for increasing the pressure of the heated biogas sample exiting the gas dryer;

d) a gas analyzer unit for measuring the quantity of a contaminant selected from the group consisting of H₂O, CO₂, H₂S, NH₃, siloxanes, VOC, and O₂ present in the dried and pressurized and heated, biogas sample;

e) a source of compressed industrial grade purge gas input, said purge gas being passed through a pressure regulator to said gas dryer unit and said gas analyzer unit; and

f) a gas exhaust for venting the analyzed biogas sample.

2. The system according to claim 1 further including a solenoid actuated input switch for selecting a particular output from a biogas scrubbing array.

3. The system according to claim 2 further including an in-line particulate filter associated with said first pressure regulator.

4. The system according to claim 2 where the gas sample input to the gas sample dryer unit is at a pressure of 1-7 psi.

5. The system according to claim 4 where the gas sample input to the gas analyzer unit is at a pressure of 30 psi.

6. The system of claim 2 where the biogas at the point of extraction is at negative pressure, said system further including an extraction pump and associated pressure regulator for increasing the pressure to positive of the extracted biogas sample prior to introduction into a gas dryer unit.

7. The system according to claim 6 where the gas sample input to the gas analyzer unit is at a pressure of 30 psi.

8. The system according to claim 5 where the gas exhaust is vented to flare.

9. A system for conditioning and analyzing a sample extracted from at least one stream of a biogas where the biogas contains one or more contaminants selected from the group consisting of H₂O, CO₂, H₂S, NH₃, C₂H₆, siloxanes, VOC, and O₂ intermixed with CH₄, said system, comprising:

a) at least a first gas pipeline takeoff probe for extracting a low pressure biogas sample, a heated probe housing, a biogas communication line limiting dew point dropout of the biogas sample conveying the heated biogas sample to a solenoid controlled valve switch and into a sample analyzer cabinet;

b) a first pump and a first pressure regulator for increasing the pressure of the heated gas sample for introduction into a gas dryer unit;

c) a second pump and a second pressure regulator for further increasing the pressure of the heated gas sample exiting the dryer;

d) a gas analyzer unit for measuring the quantity of a contaminant selected from the group consisting of H₂O, CO₂, H₂S, NH₃, C₂H₆, siloxanes, VOC, and O₂ present in the dried and pressurized and heated, biogas sample;

e) a source of compressed industrial grade purge gas input gas passed through a pressure regulator to gas dryer unit and said gas analyzer unit; and

f) a gas exhaust for venting the analyzed biogas sample.

10. The system according to claim 9 further including a solenoid actuated input switch for selecting a particular output from a biogas scrubbing array.

11. The system according to claim 10 further including an in-line particulate filter associated with said first pressure regulator.

12. The system according to claim 11 where the gas sample input to the gas sample dryer unit is at a pressure of 1-7 psi.

13. The system according to claim 12 where the gas sample input to the gas analyzer unit is at a pressure of 30 psi.

14. The system according to claim 9 where the gas exhaust is vented to flare.

15. A method for conditioning a biogas sample for confirmation of its quality, comprising the steps of:

extracting a biogas sample from a select source;

regulating the temperature and pressure of the extracted biogas sample;

feeding the pressure and temperature regulated biogas sample into a dryer for removal of moisture;

increasing the pressurize of the biogas sample output from the dryer; and

feeding said biogas sample to a dryer gas component analyzer for measuring the component in the biogas sample.

16. The method of claim 15 further including the step of selecting a particular of multiple biogas sample source feeds for feeding to the dryer.

17. The method of claim 16 further including the steps of purging the biogas sample from the dryer and introducing a fresh sample to the dryer.

18. The method of claim 17 further including the step of venting the biogas sample from the analyzer to flare.