A study on municipal solid waste (MSW) combustion in N_2/O_2 and CO_2/O_2 atmosphere from the perspective of TGA

摘要

In this paper, the combustion behavior of municipal solid waste (MSW) is carried out in a thermogra-vimetric analyzer under different N2/O_2 and CO_2/O_2 atmospheres with temperature ranging from 100℃ to 1000 ℃. TG (thermogravimetric) and DTG (derivative thermogravimetric) curves are analyzed. The nth order reaction fitting model is used to yield the activation energy of reduction process according to the degree of conversion. The results indicate that all samples lose most their weight between 200℃ and 540℃. As the oxygen concentration increased, conversion rate curves and DTG curves shift to lower temperature without significant change in its shape. At the same oxygen concentration, the peak values in CO_2/O_2 atmosphere are smaller than those in N_2/O_2 atmosphere, indicating that CO_2 has a higher inhibitory effect than N_2 on MSW combustion. After 600℃, the weight loss peak appears much later in CO_2/O_2 atmosphere than it does in N2/O_2 atmosphere. With the increase of heating rate, the maximum weight loss rates of samples increase obviously. The three-step reaction of nth order reaction model fits the weight loss very well.