Nitrogen fuel bound

At the high temperatures found in MHD combustors, nitrogen oxides, NO, are formed primarily by gas-phase reactions, rather than from fuel-bound nitrogen. The principal constituent is nitric oxide [10102-43-9] NO, and the amount formed is generally limited by kinetics. Equilibrium values are reached only at very high temperatures. NO decomposes as the gas cools, at a rate which decreases with temperature. If the combustion gas cools too rapidly after the MHD channel the NO has insufficient time to decompose and excessive amounts can be released to the atmosphere. Below about 1800 K there is essentially no thermal decomposition of NO. 

Leppalahti, Jukka. Behaviour of fuel-bound nitrogen in gasification and in high-temperature NH3 removal processes. 1998. 77 p. + app. 205 p. 

Thus, the reaction system cannot be quenched to prevent NO formation from fuel-bound nitrogen, as is the case with atmospheric nitrogen. In fact, in the... 

Despite the authors assertion that alkylated heteroaromatic compounds provide a better model for fuel-bound nitrogen than do the unsubstituted heterocycles, their pyrolytic study remains the most comprehensive look at substituted heteroaromatic chemistry, even several years later/ Kinetic studies are more common in the literature Frerichs et al. examined the reaction of the picolines with oxygen atom, while Yeung and Elrod studied reactions of HO with pyridine and its methyl- and ethyl-substituted derivatives.Both groups noted that the presence of nitrogen did not demonstrably affect the species chemistry generally, reactivity is comparable to toluene. 

Five separate mechanisms have been identified that can lead to formation of nitrogen oxides in significant quantities. Four of these mechanisms are initiated by fixation of the molecular nitrogen contained in the combustion air. For fuels such as coal or biomass that contain nonnegligible amounts of fuel-bound nitrogen, so-called fuel-NO constitutes an additional formation route. 

Assess the potential for minimizing nitrogen oxide (N0X) emissions from the six, high fuel-bound nitrogen liquids. 

Pillsbury, P. W., Cohn, A., Mulik, P. R., and Stein, T. R., "Investigating Combustion Turbine Burner Performance with Coal Derived Liquids Having High Fuel Bound Nitrogen, "ASME Paper 78-GT-126, 1978. 

Although gas turbine combustion systems operate with overall air/fuel ratios which are quite fuel-lean, perhaps three times stoichiometric, stabilization of the combustion process requires that a portion of the combustor, the primary zone, operate stoichiometric or fuel-rich. Under fuel-lean conditions, fuel-bound nitrogen can be converted directly to N0X. Under fuel-rich conditions, fuel-bound nitrogen can be converted to HCN and NH3 in addition to N0X. Of course, in either case, the most desirable product of converted fuel nitrogen would be molecular nitrogen,... 

H-Coal, and EDS middle distillates, and hydrotreated Paraho shale oil residual were tested in a subscale 5-inch diameter, staged rich-lean combustor at conditions representative of baseload and part power settings of 30-MW utility combustion turbine. A minimum NO emission level corrected to 15% oxygen of approximately 35 ppmv was attained for all the fuels despite fuel bound nitrogen levels of up to 0.8 percent by weight. 

The NO levels obtained from the staged combustion investigation were substanially less than obtained from a lean combustor (Figure 12). At exit temperatures representative of baseload operation, the rich-lean combustor produced N0X levels approximately one-third the levels associated with the lean combustor. Unlike the staged combustor emissions increased with increased fuel-bound nitrogen. 

N0X emissions were independent of the fuel-bound nitrogen content. A minimum N0X level of approximately 37 ppmv (corrected to 15% oxygen) was attained even for fuels containing... 

An LHV gas may contain up to a few thousand ppm of ammonia, produced from fuel-bound nitrogen during the gasification of a solid fuel. One of the major challenges in the catalytic combustion of LHV gases is to circumvent the formation of NO from this ammonia. The selectivity for this reaction is strongly dependent on the air-fuel ratio in the catalytic combustor and on the catalyst type [102,105], Clark et al. [102] and Tucci... 

C. Jung-Min Sung, L.A. Kennedy, and E. Ruckenstein, The effect of nitrogen content on the oxidation of fuel bound nitrogen in a transition metal oxide catalytic combustor, Comb. Sci. Tech. 47 315 (1984). 

Fuel-bound Nitrogen Conversion Results from Gasification of Biomass in two Different Small Scale Fluidized Beds... 

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