Ultra Low NOx Emission Burners
Ultra low NOx burners are required in many areas of California as well as several other states. All of ALZETA’s burner technologies can deliver less than 7 ppm NOx in most applications. Key to achieving reliable and repeatable results is our premixed, surface-stabilized combustion that provides uniform heating and operates at minimum combustion temperatures.
Combustion temperatures are minimized by operating lean (lower fuel-to-air ratio). This may be achieved by simply increasing combustion air, or diluting with flue gas or another inert gas. While other burners may encounter combustion instability at the lean conditions needed for ultra low NOx, ALZETA’s surface-stabilized combustion is complete and uniform. Heat transfer remains effective within the furnace or combustion chamber, flame length is unchanged and predictable, and CO emissions remain low. These characteristics also make ALZETA’s low emission burners ideal for operation on low Btu content fuels such as biogas or digester gas, in that the inert gases contained in the fuel further reduce combustion temperatures. NOx emissions are similar or lower than with conventional fuels.
ALZETA's Low NOx Combustion Technology
- ALZETA’s CSB™ metal-fiber burner is the most common technology for ultra low NOx applications. Its high output matches the volumetric heat release needed in most furnaces and boilers, making it ideal for retrofit applications. Often, a burner can be installed with minimum modification to the boiler or furnace. In addition, ALZETA can provide upgraded control systems using O2 trim or metered fuel and air flow.
- The Duratherm™ ceramic-fiber burner is often used when ultra low NOx, low heat flux and very uniform heating are required. Fired heaters have been designed around the ceramic burner surface for “fragile fluid” processes, improving both heat transfer and system efficiency. For these applications, compliance with low emissions requirements is an additional benefit.
- For gas turbine applications, ALZETA’s nanoSTAR™ injector will deliver under 3 ppm NOx with only modest modification to the turbine’s combustion section. Turbine manufacturers now have an alternative to post-combustion NOx reduction, while keeping within the original turbine installation envelope.
For areas where ultra low NOx regulation is pending or anticipated, an equipment owner can install an ALZETA burner now and operate it as a low NOx burner to receive the benefits of uniform heat distribution, simple controls, and quick response; while knowing that the burner technology can be adjusted to comply with future lower NOx requirements.