TY - JOUR
TI - Experimental study on no heterogeneous reduction by char
AU - Yu Shilin
AU - Lv Zhaomin
AU - Miao Yang
AU - Xiong Xiaohe
AU - Tan Houzhang
JN - Thermal Science
PY - 2022
VL - 26
IS - 5
SP - 4147
EP - 4156
PT - Article
AB - The NO heterogeneous reduction by char is one of the most prominent options  to control NOx emissions from coal-fired power plants. Experiments on the  char-NO heterogeneous reaction were carried out in an electrically heated  fixed-bed reac-tor to investigate the effect of temperature, type of char,  pretreatment method, additives and reaction atmosphere on the NO reduction  capacity of char. The re-sults showed that temperature plays a crucial role  in the NO reduction by differ-ent char. The kinetic analysis showed that  char-NO heterogeneous reaction is controlled by chemical kinetic below Tt  and by diffusion kinetic above Tt. The value of transition temperature Tt  depends on the types of char and ranges from 600°C to 800°C. The  synergistic effect of specific surface area, mineral abun-dance and  reactivity combine to result in the reduction efficiencies of different  char. Oxygen has a promoting effect on the char-NO heterogeneous reaction,  and the oxygen content of the promoting peak moves to low oxygen content  with in-creasing temperature. At 1050 °C, the denitrification efficiency at  0.25% O2 con-tent is 12.7% higher than that under oxygen-free conditions. At  high tempera-tures, the promotion of the char-NO heterogeneous reaction by  CO and the inhi-bition of the reaction by CH4 were more obvious.