Reduction and Control Technologies
The graph below illustrates the relationship between relative NOx emission levels and fuel-bound nitrogen content.
Because fuel-bound nitrogen plays such an important role in total NOx emissions from fuel combustion in boilers, switching from high-nitrogen fuels, such as residual oil to lower nitrogen fuels such as natural gas, can be an effective strategy. As an example, switching from residual oil with 0.6% nitrogen to natural gas can result in a 50-80% reduction in NOx emissions. In addition, SO2 emissions are eliminated.