Main influencing factors and coal fly ash characteristics of gasoues fuel reburning process  

作　　者：苏胜 向军 孙路石 胡松 

机构地区：[1]State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology

出　　处：《Journal of Central South University》2009年第1期160-165,共6页中南大学学报（英文版）

基　　金：Projects(50806025; 50721005) supported by the National Natural Science Foundation of China

摘　　要：The unburned carbon concentration in fly ash and the influence of main factors on the reduction of nitrogen oxides during gaseous fuel reburning process were experimentally studied in a 36 kW down-fired furnace when five typical coals with different qualities were served as the primary fuel. It is found that the higher nitrogen oxide reduction efficiency can be obtained by reburning process when the coal used as the primary fuel contains more volatile matter. But under the optimizational operating conditions, both above 50% nitrogen oxide reduction and low carbon loss can be achieved by reburning process even though the primary fuel is the low-volatile coal. The experimental results show that the reasonable residence time in reburn zone is 0.6-0.9 s, the appropriate gaseous reburn fuel percentage is 10%-15% and the optimal average excess air coefficient in reburn zone is 0.8-0.9. These results extend the ranges of the key parameter values for reburning process with respect to that the low-volatile coals are used as the primary fuel.The unburned carbon concentration in fly ash and the influence of main factors on the reduction of nitrogen oxides during gaseous fuel reburning process were experimentally studied in a 36 kW down-fired furnace when five typical coals with different qualities were served as the primary fuel. It is found that the higher nitrogen oxide reduction efficiency can be obtained by reburning process when the coal used as the primary fuel contains more volatile matter. But under the optimizational operating conditions, both above 50% nitrogen oxide reduction and low carbon loss can be achieved by reburning process even though the primary fuel is the low-volatile coal. The experimental results show that the reasonable residence time in reburn zone is 0.6-0.9 s, the appropriate gaseous reburn fuel percentage is 10%-15% and the optimal average excess air coefficient in reburn zone is 0.8-0.9. These results extend the ranges of the key parameter values for reburning process with respect to that the low-volatile coals are used as the primary fuel.

关 键 词：coal fly ash unburned carbon nitrogen oxides coal combustion rebuming down-fired furnace 

分 类 号：TK16[动力工程及工程热物理—热能工程]