A hot-flow model analysis of the MSW incinerator

Abstract

A hot-flow model incinerator was constructed to simulate the combustion chamber of mass-burn municipal solid waste (MSW) incinerator. Experiments using the reduced scale simplified model were designed to reproduce the physical processes. The Current study focuses on the gas phase mixing and the subsequent oxidative destruction of incomplete combustion products. Excessive carbon monoxide is generated by operating the gas burner under fuel-rich conditions, and is supplied into the furnace chamber as a hot gas stream, where fresh air is provided by the secondary air injection. Mixing is quantified by measuring the local gas concentrations (CO and O-2) and temperatures since the destruction rate of CO is controlled by oxygen availability and chemical kinetic rates. The degree of mixing is monitored while the design alternatives of the secondary air injection pattern are systematically adjusted. This effect of the secondary air injection schemes on the degree of mixing are observed, and the measurements of temperature fluctuation with fine-wire thermocouples are performed for the quantitative evaluation of mixing. The results agree well with the plausible scenario of mixing and provide a better understanding of the mixing process. The hot dow accompanying chemical reactions in the model incinerator is also analysed numerically using the computational fluid dynamics codes to bolster the understanding of the experimental results. The modelling results compare reasonably well with experimental data. This comparison helps to cross-check the results. (C) 1997 by John Wiley & Sons, Ltd.