Designs for enhanced reliability and calibration of landfill gas measurement and control devices

An apparatus for sampling landfill gas flowing through a pipe, the apparatus comprising:

• an enclosure comprising a gas sampling port, the gas sampling port configured for coupling to a section of the pipe;
• at least one sensor disposed in a region of the enclosure, the at least one sensor being coupled to the section of the pipe through the at least one gas sampling port;
• a calibration port configured for connection to at least one source of gas of known composition;
• and
• a valve connected between the calibration port and the at least one sensor so as to enable gas to flow from the calibration port to the at least one sensor while isolating the at least one sensor from the gas sampling port, wherein the apparatus is configured such that the valve is actuated in response to a fitting being connected to the at least one calibration port.

An apparatus for sampling landfill gas flowing through a pipe, the apparatus comprising:

• a sampling subsystem comprising:
• a gas inlet port and a gas outlet port;
• a region comprising a gas sampling port, the gas sampling port configured for coupling to a section of the pipe;
• at least one sensor coupled to the gas outlet port;
• and
• a gas flow passage from the gas inlet port, over the at least one sensor, and to the gas outlet port;
• a gas sample comprising 35% CO2, 50% CH4, and 15% N2;
• at least one calibration port configured for connection to at least one source of gas of known composition, the at least one source of gas comprising the gas sample;
• and
• at least one valve connected between the at least one calibration port and the sampling subsystem so as to enable gas to flow from the at least one calibration port to the at least one sensor while isolating the at least one sensor from the gas sampling port.