基于可视化大尺寸快速升温热重分析装置的混合固废热解和燃烧特性的实验研究OA北大核心CSTPCD

The combustion of municipal solid waste(MSW)goes through three stages:drying,pyrolysis and volatiles combustion,and char combustion.Key parameters describing the pyrolysis and combustion kinetics of samples include sample mass,temperature,size,and igni-tion characteristics.The primary features of the actual solid waste incineration process include high heating rate(above 400 K/min),large sample size,complex composition,and volume shrinkage of the sample.However,conventional experimental equipment used for measuring the pyrolysis and combustion of solid waste,such as TGA,macro TGA,and drop tube furnace,have limitations in terms of heating rate or sample size,making it difficult to simultaneously ob-tain information on the sample's mass,temperature,and image.A visualized fast heating macro thermogravimetric analysis device(referred as macro TGA)was built to measure the mass,tem-perature,and image information of paper,PET,pine,kitchen waste,and their mixed samples under slow heating(10 K/min,15 K/min,and 25 K/min)and fast heating(approximately 500 K/min)conditions.The results showed that the heating rate has a significant impact on the py-rolysis and combustion kinetic characteristics of the mixed sample.In slow heating mode,DTG curve of the mixed sample exhibits multiple peaks,and the occurrence time of these peaks corre-spond to the peak of DTG curves of its four components.In rapid heating mode,the pyrolysis ranges of the components in the mixed sample tend to overlap,and the number of peaks in DTG curve decreases to one.Temperature and image information indicate that under slow heating at 15 K/min,the ignition time of the mixed sample's internal and surface regions is basically the same,and the center temperature of the sample during ignition is 191℃,with combustion occur-ring on the sample surface.In rapid heating mode,volatile combustion flames are immediately observed on the sample surface after heating initiation,followed by gradual expansion of combus-tion into the sample's interior.As the combustion progresses,the sample size continuously shrinks until it is completely burned.