Saturday, May 27, 2017

A Precise Combustion Airflow Measurement Station Designed for the Power Industry

The objectives in the power industry today are twofold;
  • To lower emissions 
  • Increase plant performance
Precise measurement of combustion airflow and fuel rates positively contributes to achieving those objectives, by providing the information needed to optimize stoichiometric ratios and facilitate more complete, stable combustion. Usable measurements cannot be obtained from existing devices such as Venturis, foils, jamb tubes, etc., or instrumentation such as thermal anemometers due to limited available straight duct runs, low flow rates, proximity to modulating control dampers, broad turndown range, and high concentrations of airborne particulate (flyash). 

There is a product, however, by Air Monitor Corporation that reliably and consistently provides precise combustion airflow measurement. The CA Station has both an integral airflow processing cell and Fechheimer-Pitot measurement technology and is engineered to meet the challenging operating conditions of the typical power plant. It's capable of providing mass flow measurement of PA, SA, and OFA within an accuracy of ±2-3% of actual airflow.
CA Station
The Air Monitor CA Station

While the main functions of primary air are to first dry and then pneumatically convey the pulverized coal from the mill to the individual burners, it also determines coal particle velocity at the burner exit, influencing the flame position relative to the burner tip and impacting flame stability, both key factors in achieving optimized burner performance. Accurate PA measurement obtained with a CA Station can contribute to reducing NOx and CO, improving flame stability, avoidance of coal pipe layout, minimizing LOI/UBC, reducing waterwall corrosion, and increasing combustion efficiency.

The CA Station is also ideally suited to measure SA entering each burner level of a partitioned windbox, SA being taken out of a windbox to supply multiple OFA ports, at the ducted inlet of FD fans, and bulk SA entering each windbox of a corner fired unit.

For more information about the CA Staton, contact Power Specialties by visiting http://www.powerspecialties.com or calling (816) 353-6550.