Experimental Study on Low NOx Emission Using Blast Furnace Gas Reburning and Industrial Application in Stoker Boiler

摘要

To get the modification method of blast furnace gas reburning technology on one 75t/h stoker boiler, the effect of some key factors such as stoichiometric coefficient, residence time, temperature and heat ratio input on NOx formation regulation was studied on a one-dimensional test system with fuel reburning. The results showed that prolonging the reburn zone residence time can help to lower the NOx emission and the best time was 0.8s. There existed an optimum value 1.0 for reburn zone stoichiometric coefficient. The NOx reduction efficient increased with the increase of the reburn heat input and the reburn zone temperature. The use of blast furnace gas reburning technology has been successfully implemented during the modification of stoker boiler, the NOx reduction rate was over 50%.