Work

Combustion in a coke oven battery: Numerical modeling and testing with focus on NOx emission

Year: 2025

Type: article

Abstract: In the present study numerical simulations are exploited to give insight on a heating flue chamber, typical unit of a coke oven battery heating wall, employing fuels from steelmaking process. Particular attention is drawn on the NOx production, which represent the main source of pollution which needs to be minimized in the early design stages. Such goal is pursued by CFD simulations based on a novel approach: a detailed model of combustion allows to directly estimate the radicals involved in the formation of NOx estimated by thermal, prompt and reburn mechanism, the last leading to “depletion” of nitrogen oxides in fuel-rich zones. A 24 species with 134 reactions mechanism and the Eddy Dissipation Concept (EDC) for the turbulence-chemistry interaction are employed. The simulations are validated by comparison against data from plant testing, in two different operating conditions: so, it is proven that the overall modeling approach proposed is accurate and that reburn mechanism is essential to properly evaluate the emission levels in this application. Furthermore, sensitivity analyses are carried out assessing the influence on furnace performance of the main operating parameters like fuel thermal input, inlet air temperature and excess air fed, which can also represent the main source of uncertainty when setting the boundary conditions for CFD simulations.The present work sheds light on the combustion characteristics and the balance between the different NOx formation mechanisms inside a heating flue combustion chamber, also providing a complete, accurate and validated modeling approach, alternative to others already available in the literature.

Source: Thermal Science and Engineering Progress

DOI: 10.1016/j.tsep.2025.104435