Alternately rich and poor reaction utilizing oxygen flue gas denitration process

The present invention relates to a process using an oxygen rich and poor alternation flue gas denitration, the higher oxygen content of boiler flue gas flow through the catalyst layer of oxidizing HC-SCR nitrogen oxide adsorption bed; adsorbing nitrogen oxides the flue gas is collected; the low oxygen content gas to flow through the reducing agent HC-SCR catalyst layer after the adsorption of nitrogen oxides; repeating steps (1) and (2) a reducing agent and the boiler flue gas alternately flows HC-SCR catalyst layer. The present invention provides an oxygen rich and poor alternately HC-SCR denitration process may take advantage of promoting the oxygen in the flue gas adsorption process, and to avoid excessive concentration of oxygen inhibition of the reduction process, improve the reaction efficiency of the denitration process.