Nitrogen release during reaction of coal char with O2, CO2, and H2O

Fuel Nitrogen Evolution during Coal Pyrolysis and Gasification

“…Mckenzie et al [24] pointed out that the introduction of steam into the gasification system promoted the char-N conversion into NH 3 , inhibiting NH 3 decomposition. Park and co-workers [25] also reported the promotion of NH 3 formation with increased steam concentration. However, our experiments have shown that excess steam inhibits NH 3 The steam volume fraction when the yield of NH 3 reaches its maximum is three times that when the yield of HCN is maximum.…”

Homogeneous and heterogeneous contributions of CO 2 and recycled NO to NO emission difference between air and oxy-coal combustion

“…Al contents of coal and char were tested by X-ray fluorescence (XRF). Table 1 Detailed influence of CO 2 and recycled NO on nitrogen transformation [5,8,[10][11][12][13][14].…”

“…Duan et al [8,9] found that during long residence time devolatilization (>150 s), CO 2 enhanced the conversion rate of coal nitrogen (coal-N) to volatile-N by releasing more HCN and less NH 3 . Various possible reaction schematics are summarized in Table 1 from the reported literatures [5,8,[10][11][12][13][14]. In regards to the influence of homogeneous impact of CO 2 , Eq.…”

“…As a result, these composition changes could weaken NO formation from volatile-N [11,12]. The heterogeneous reactions between char nitrogen (char-N) and CO 2 could generate N 2 [14] or HCN [8] rather than NO in oxidation atmosphere. These reactions may decrease the amount of direct NO generation from char-N.…”

Theoretical Investigation of the Formation Mechanism of NH3 and HCN during Pyrrole Pyrolysis: The Effect of H2O

“…They found that the moisture content had a significant influence on the tar yield and light tar content, and H 2 O could upgrade the low-rank coal during pyrolysis [23]. Moreover, Park and co-workers [24] found that studies of coal-N release in the presence of H 2 O were more authentic than those of the only pyrrole, as H 2 O inevitably existed in the coal utilization process. However, there are limited studies focusing on the effect of H 2 O on pyrrole pyrolysis at present.…”