Reducing NOx from Fired Heaters and Boilers
Look at NOx time line and find out where do you stand with respect to NOx compliance. Introduction
Since 1970, EPA has been tracking six principal pollutants- carbon monoxide, lead, nitrogen oxides, particulate matter, sulfur oxides, and volatile organic compounds. All have decreased significantly since the passage of the clean air act in 1970 except for nitrogen oxides. Reducing NOx emissions is a crucial component of EPA’s strategy for cleaner air. Nitrogen oxides are formed when fuel is burnt at high temperatures, as in a combustion process. The primary sources on NOx are motor vehicles, electric utilities, and other industrial, commercial, and residential sources that burn fuel. In the last three months, Houston has taken over Los Angeles as the smoggiest city in USA.
In the last 25 years, a number of technologies have surfaced and have been implemented in process heaters and industrial boilers. In this series, we are going to take stock of the state of art NOx reduction methods and what can be expected in the next decade as we continue our battle for NOx reduction..
What is NOx
What is NOx? Nitrogen oxides or NOx is the generic term for a group of highly reactive gases all of which contain nitrogen and oxygen in various proportions. Many nitrogen oxides are colorless and odorless. . Two of the most common oxides of nitrogen are: NO - Nitric Oxide and NO2 - Nitrogen Dioxide. In stationary source, combustion approximately 90% of NOx formed is NO. After NO leaves, a stack, in the presence of sunlight, ozone, and VOCs, it becomes NO2, which (in extreme cases) appears as a reddish-brown plume. It can cause photochemical smog and/or acid rain
