Nitric Oxide Emission Reduction in Reheating Furnaces through Burner and Furnace Air-Staged Combustions

In this study, a series of experiments were conducted on testing facility and real-scale furnace, for analyzing the nitric oxide (NO) emission reduction. The effects temperature, oxygen concentration, amount secondary combustion air investigated in single-burner system. Additionally, NO-reduction rate before after modifications both burner furnace air-staged evaluated reheating furnace. air-to-fuel equivalence ratio (λ) individual zones was optimized NO reduction without any incomplete combustion. results indicated that controlling λ single-zone decreased linearly with decrease values firing tests (top-heat, bottom-heat, bottom-soak zones). Moreover, multi-zone control at 1.13 (top-preheat), 1.0 (bottom-preheat), (top-heat), 0.97 (bottom-heat), (top-soak), (bottom-soak). condition, reduced emissions by approximately 23%, as comparison data obtained modifications. Thus, combined application combustions facilitated NO-emission