New burner monitoring system helps control NOx emissions
The heating plant at the University of Alberta has installed low NOx burners on its two newest boilers to ensure compliance with Canada?s strict air pollution regulations. The plant supplies heating steam, de-mineralized water, compressed air and some electricity to a campus population of approximately 45,000 people.
By law, the university must have independent air quality surveys for NOx emissions. ONOx emissions must be within the levels specified in our license to operate and we have continuous monitoring of stack gases to prove that we are within limits,O said Ray Kjenner, heating plant manager.
He credits the installation of highly efficient, low emission burners fitted with a sophisticated burner management system with keeping his plant within limits.
OWith this size burner, safety is a very serious problem. So we needed a reliable system to ensure a true and accurate signal if a burner flame should be extinguished. The IRIS burner management flame-monitoring system provided this,O Kjenner said.
The burner management system monitors the flame, removing the risk of explosion by providing instant fuel valve closure if flame is lost.
The low NOx burners exhibit uniform flame throughout the furnace, in contrast to more conventional burners where flames tend to be more individual and distinct. As a result, flame location and discrimination is much more difficult on the low NOx system.
The flame monitors also monitor the ultraviolet radiation of the combustion process, rather than the residual heat of the boiler or furnace. They require sophisticated data communications capability to transmit boiler condition changes instantly. Since the system functions in a harsh environment, both the monitor and the signal processor must be designed and packaged for rugged environments.