Hazardous gas detection system for a gas turbine enclosure

Patent metadata

Field	Value
Publication number	US-9366192-B2
Application number	US-201414176835-A
Country	US
Kind code	B2
Filing date	Feb 10, 2014
Priority date	Feb 10, 2014
Publication date	Jun 14, 2016
Grant date	Jun 14, 2016

Abstract

A hazardous gas detection system includes a first and second plurality of air sampling ports in fluid communication with an exhaust duct of a gas turbine enclosure. The first and second plurality of air sampling ports is fluidly connected to a first and second outlet orifice respectfully. A primary sensor is in fluid communication with the first outlet orifice and a secondary sensor is in fluid communication with the second outlet orifice. The primary and secondary sensors generate signals indicative of hazardous gas concentrations in first and second aggregated exhaust air samples. A computing device monitors the hazardous gas concentrations, monitors functionality of the primary and secondary sensors and generates a command signal indicating an operating mode for the gas turbine based on at least one of the hazardous gas concentrations in the first and second aggregated exhaust air samples and the functionality of the primary and secondary sensors.

First claim

What is claimed is:

1. A hazardous gas detection system, comprising:
a first air sampling probe disposed within an exhaust duct of a gas turbine enclosure, the first air sampling probe having a first plurality of air sampling ports in fluid communication with the exhaust duct and fluidly connected to a first outlet orifice;
a primary sensor disposed outside of the exhaust duct and in fluid communication with the first outlet orifice, wherein the primary sensor generates a first signal indicative of a hazardous gas concentration in a first aggregated exhaust air sample collected from the first plurality of air sampling ports;
a second air sampling probe disposed within the exhaust duct, the second air sampling probe having a second plurality of air sampling ports in fluid communication with the exhaust duct and fluidly connected to a second outlet orifice;
a secondary sensor disposed outside of the exhaust duct and in fluid communication with the second outlet orifice, wherein the secondary sensor generates a second signal indicative of a hazardous gas concentration in a second aggregated exhaust air sample collected from the second plurality of air sampling ports; and
a computing device in electronic communication with the primary and secondary sensors, wherein the computing device receives the first and second signals, wherein the computing device is programmed to:
monitor the hazardous gas concentration in the first and second aggregated exhaust air samples;
monitor functionality of the primary and secondary sensors; and
generate a command signal indicating an operating mode for a gas turbine based on at least one of the hazardous gas concentration in the first and second aggregated exhaust air samples and the functionality of the primary and secondary sensors.

2. The hazardous gas detection system as in claim 1 , wherein the first plurality of air sampling ports are fluidly connected in series via one or more tubes and the second plurality of air sampling ports are fluidly connected in series via one or more tubes.

3. The hazardous gas detection system as in claim 1 , wherein at least one of the primary sensor and the secondary sensor comprises an infrared gas sensor.

4. The hazardous gas detection system as in claim 1 , wherein at least one of the primary sensor and the secondary sensor comprises a methane gas sensor.

5. The hazardous gas detection system as in claim 1 , further comprising at least one of a fluid filter, a flow switch, a flow indicator, an aspirator and an instrument air supply disposed downstream from at least one of the first air sampling probe and the second air sampling probe.

6. The hazardous gas detection system as in claim 1 , further comprising a flow sensor in electronic communication with the computing device, wherein the flow sensor communicates a signal to the computing device indicative of air flow rate across at least one of the primary sensor and the secondary sensor and wherein the command signal is at least partially based on the air flow rate.

7. The hazardous gas detection system as in claim 1 , wherein the operating mode for the gas turbine comprises one of a normal operating mode, a controlled shut down mode or a trip mode.

8. The hazardous gas detection system as in claim 1 , wherein the operating mode corresponds to a normal operating mode when one of the primary and secondary sensors is fully functional and the hazardous gas concentration from the corresponding fully functional primary or secondary sensor is below a predetermined percentage of a lower explosive limit.

9. The hazardous gas detection system as in claim 1 , wherein the operating mode corresponds to a controlled shutdown operating mode when one of the primary and secondary sensors is fully functional and the hazardous gas concentration from the corresponding fully functional primary or secondary sensor is between a minimum predetermined percentage and a maximum predetermined percentage of a lower explosive limit.

10. An enclosure for a gas turbine, comprising:
a ventilation system comprising a plurality of inlet ducts that provide for fluid communication into the enclosure and at least one exhaust duct that provides for fluid communication out of the enclosure; and
a hazardous gas detection system, comprising:
a first air sampling probe disposed within the exhaust duct, the first air sampling probe having a first plurality of air sampling ports in fluid communication with the exhaust duct and fluidly connected to a first outlet orifice;
a primary sensor disposed outside of the exhaust duct and in fluid communication with the first outlet orifice, wherein the primary sensor generates a first signal indicative of a hazardous gas concentration in a first aggregated exhaust air sample collected from the first plurality of air sampling ports;
a secondary sensor disposed outside of the exhaust duct and in fluid communication with one of the first outlet orifice and a second outlet orifice of a second air sampling probe disposed within the exhaust duct, the second air sampling probe having a second plurality of air sampling ports in fluid communication with the exhaust duct, wherein the secondary sensor generates a second signal indicative of a hazardous gas concentration in a second aggregated exhaust air sample collected from the second plurality of air sampling ports; and
a computing device in electronic communication with the primary and secondary sensors, wherein the computing device is programmed to:
monitor the hazardous gas concentration in the first and second aggregated exhaust air samples;
monitor functionality of the primary and secondary sensors; and
generate a command signal indicating an operating mode for the gas turbine based on at least one of the hazardous gas concentration in the first and second aggregated exhaust air samples and the functionality of the primary and secondary sensors.

11. The enclosure as in claim 10 , wherein the first plurality of air sampling ports are fluidly connected in series via one or more tubes and the second plurality of air sampling ports are fluidly connected in series via one or more tubes.

12. The enclosure as in claim 10 , wherein at least one of the primary sensor and the secondary sensor comprises a methane gas sensor.

13. The enclosure as in claim 10 , further comprising at least one of a fluid filter, a flow switch, a flow indicator, an aspirator and an instrument air supply disposed downstream from at least one of the first air sampling probe and the second air sampling probe.

14. The enclosure as in claim 10 , further comprising a flow sensor in fluid communication with at least one of the first and second flow sensors and in electronic communication with the computing device, wherein the flow sensor communicates a signal to the computing device indicative of air flow rate across at least one of the primary sensor and the secondary sensor, wherein the command signal is at least partially based on the air flow rate.

15. The enclosure as in claim 10 , wherein the operating mode comprises one of a normal operating mode, a controlled shut down mode or a trip mode.

16. The enclosure as in claim 10 , wherein the operating mode corresponds to a normal operating mode when one of the primary and secondary sensors is fully functional and the hazardous gas concentration from the corresponding fully functional primary or secondary sensor is below a predetermined percentage of a lower explosive limit.

17. The enclosure as in claim 10 , wherein the operating mode corresponds to a controlled shutdown operating mode when one

Assignees

• Gen Electric

Inventors

• Byrd Douglas Scott
• Brooks Robert Lester
• Hochar Antoine
• Vasinis Christophe

Classifications

• G01N33/0063

  using a threshold to release an alarm or displaying means · CPC title

• F02C7/25 Primary

  Fire protection or prevention (in general A62) · CPC title

• G08B21/14

  Toxic gas alarms (G08B21/16 takes precedence) · CPC title

• G01N21/3504

  for analysing gases, e.g. multi-gas analysis · CPC title

• G01N1/2258 Primary

  in a stack or chimney · CPC title