Multi-sensor probe for monitoring combustion in a conduit

A method for measuring constituents of a gas flowing a duct;

• the method comprising:
• measuring an oxygen concentration and a temperature within the duct at multiple locations within the duct using at least one multi-sensor probe extended within the duct;
• the multi-sensor probe including:
• a tubular lance;
• a plurality of sensor pods spaced along the lance, each sensor, pod including a first port having an oxygen sensor disposed therein, and a second port having a first temperature sensor disposed therein:
• an enclosure coupled to one end of the tubular lance, the enclosure having a plurality of pressure sensors disposed therein;
• a first plurality of tubes passing through the lance, each tube of the first plurality of tubes fluidly coupled between the enclosure and the first port of a respective sensor pod of the plurality of sensor pods to selectively provide a first gas to the oxygen sensor disposed therein;
• and
• a second plurality of tubes passing through the lance, each tube of the second plurality of tubes fluidly coupled between the first port of a respective sensor pod and a respective pressure sensor of the plurality of differential pressure sensors to provide an indication of pressure within the respective first port;
• and
• controlling an operational parameter of the boiler in response to the plurality of temperature and oxygen measurements provided from the multi-sensor probe.

A gas outlet monitoring system for controlling the operation of a boiler;

• the system comprising:
• a plurality of multi-sensor probes disposed within a duct of the boiler;
• each multi-sensor probe including:
• a tubular lance;
• a plurality of sensor pods spaced along the lance, each sensor pod including a first port having an oxygen sensor disposed therein, and a second port having a first temperature sensor disposed therein;
• an enclosure coupled to one end of the tubular lance, the enclosure having a plurality of pressure sensors disposed therein;
• a first plurality of tubes passing through the lance, each tube of the first plurality of tubes fluidly coupled between the enclosure and the first port of a respective sensor pod of the plurality of sensor pods to selectively provide a first gas to the oxygen sensor disposed therein;
• and
• a second plurality of tubes passing through the lance, each tube of the second plurality of tubes fluidly coupled between the first port of a respective sensor pod and a respective pressure sensor of the plurality of differential pressure sensors to provide an indication of pressure within the respective first port;
• a processor communicatively coupled to the plurality sensors pods, the processor operative to receive oxygen concentration and temperature information from the sensor pods, and to control an actuator to change an operation parameter of the boiler in response to the respective oxygen concentration and temperature information received from the sensor pods of the respective multi-sensor probes.