Nitrogen oxides coal liquid fuels

Nitrogen oxide emissions (quantitatively expressed as nitrogen oxide, NO) from unoptimized coal derived liquid combustion were higher than that of No. 6 fuel oil or natural gas (Figure 3). 

Figure 4. Liquid synthetic fuel combustion test nitrogen oxides vs. excess oxygen. H-Coal (blend) low N0X at 40 MW.

We must be able to hold a range of scenarios with regard to each possible application. Advanced fossil-fuel technologies, especially coal-based ones, must be able to meet increasingly stringent environmental requirements for critical air pollutants (sulfur dioxide, oxides of nitrogen), as well as other environmental issues (such as liquid and solid waste), and still remain cost competitive with other fossil fuels, especially natural gas [73]. 

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