Wesley R. Bussman

Variable Test Furnace Cooling

Testing burners in the process industries requires controlling both the furnace temperature and the firing rate independently. This has commonly been done by varying the amount of insulation inside a test furnace. This paper discusses using a bayonet heat exchanger system to vary the furnace temperature at a fixed firing rate. The heat transfer inside the furnace to the heat exchanger system is considered.Copyright

Ambient Condition Effects on NOx and CO Emissions From Process Heaters

Because process heaters are typically located outside, their operation is subject to the weather. Heaters are typically tuned at a given set of conditions; however, the actual operating conditions may vary dramatically from season to season and sometimes even within a given day. Wind, ambient air temperature, ambient air humidity, and atmospheric pressure can all significantly impact the O2 level, which impacts both the thermal efficiency and the pollution emissions from a process heater. Unfortunately, most natural draft process burners are manually controlled on an infrequent basis. This paper shows how changing ambient conditions can considerably impact both CO and NOx emissions if proper adjustments are not made as the ambient conditions change. Data will be presented for a wide range of operating conditions to show how much the CO and NOx emissions can be affected by changes in the ambient conditions for fuel gas fired natural draft process heaters, which are the most common type used in the hydrocarbon and petrochemical industries. Some type of automated burner control, which is virtually non-existent today in this application, is recommended to adjust for the variations in ambient conditions.© 2008 ASME