Dorota Musiał

Application of CHEMKIN and COMSOL Programs in the Calculations of Chemical Composition of Natural Gas Combustion Products

This article presents the results of numerical calculations of chemical composition of flue gas produced by combustion of natural gas in an industrial heating device, i.e., a pusher furnace. In calculations of combustion chemistry, the CHEMKIN-PRO program was used. The gas-dynamic of flue gas was modeled with the use of the COMSOL Multiphysics program. In order to check the correctness of the plug flow reactor (PFR) model, as applied in calculations, a preliminary laboratory experiment was conducted. Based on measurement data that were obtained during the research on a laboratory stand, the boundary conditions were formulated and numerical simulations were carried out. The temperature and velocity profiles in the combustion chamber were determined with the use of the COMSOL program and were implemented in the CHEMKIN program. The obtained results of the numerical simulations performed in the experimental chamber showed high compliance with the results of measurements. This, in turn, led us to apply the analysis on a real object. The simulations of the chemical composition of flue gas in the each zone of the furnace were carried out based on the measurements data collected from the real object, i.e., a pusher furnace that is currently working in one of the steel plants located in our country.

Effective methods of reduction of nitrogen oxides concentration during the natural gas combustion

This paper contains experimental research of NOx reduction in the combustion process with the primary methods, which were applied separately and in combined systems. In addition, the pulsation disturbance (PD) was applied, that is the gas stream was disturbed to increase the intensity of reagents mixing. An experimental stand was built to determine an influence of the following primary methods: air staging, reburning and flue gas recirculation on a reduction of NOx concentration. Experiments were carried out in three combinations: air staging with reburning, reburning with recirculation and air staging with recirculation. In all these cases, the PD was simultaneously applied. Researches were carried out in a quartz combustion chamber with laboratory equipment enabled to measure all the thermal and the chemical parameters of the process. The simultaneous application of primary methods causes additional increase in NOx reduction in certain systems.