A study on combustion characteristics and kinetic model of municipal solid wastes

In this paper, our work is focused on the fundamental combustion characteristics of the combustibles in MSW and its kinetic model. The combustion reactivity of the different combustibles in MSW and their mixtures such as TG and DTA profiles were studied by thermogravimetry (TG) and differential thermal analysis (DTA). On the basis of the investigations of combustion and pyrolysis characters of the combustibles in MSW, kinetic parameters such as activation energy and preexponential factor of each combustible were determined. A kinetic model describing the combustion reactive processes of the combustibles in MSW was proposed. From the study, it can be concluded that: (1) The combustibles in MSW can mainly be divided into two types of matters-one is fibrous matter, and the other is polymer matter. (2) The combustion process of combustibles in MSW mainly consists of two stages. At the first stage, the volatile contained in fibrous matter was released, and then the released volatile matter was combusted continuously; at the second stage, the fixed carbon of fibrous matter was burned, and pyrolysis and combustion of the polymer matter happened at the same time. (3) The combustion rate of the combustibles in MSW can be expressed by a weighted sum of rates of each combustible, and the complex combustion processes of combustibles in MSW can be described by simple kinetic model. The computed results of the kinetic model can mostly fit experimental data.