Effects of low-temperature pretreatment on enhancing properties of refuse-derived fuel via microwave irradiation

Abstract

The present study focuses on pretreatment of enhancing the properties of refuse-derived fuel (RDF) via low-temperature microwave irradiation. These improved properties include lower chlorine content, a more porous surface structure and better combustion characteristics. In this study, low-temperature microwave irradiation was carried out in a modified microwave apparatus and the range of temperature was set to be 220-300℃. We found that the microwave absorbability of RDF was enhanced after being partly carbonized. Moreover, with the increasing of the final temperature, the organochlorine removal ratio was greatly increased to 80% and the content of chlorine was dramatically decreased to an extremely low level. It was also interesting to find that the chlorine of RDF was mainly released as HCl rather than organic chloride volatiles. The finding is just the same as the polyvinyl chloride pyrolysis process. In addition, pores and channels emerged during the modifying operation and the modified RDF has better combustibility and combustion stability than traditional RDF. This work revealed that low-temperature modification of RDF via microwave irradiation is significant for enhancing the quality of RDF and avoiding HCl erosion of equipment substantially.

Effect of granulation on chlorine-release behavior during municipal solid waste incineration

“…Dai et al 18 achieved a 90% reduction in chlorine release at 1000 °C by adding MgCO 3 with 10% of the total waste mass consists.PVC: (CH 2 CHCl) n → n HCl + n C 2 H 2 NaCl: 2NaCl + SO 2 + 0.5O 2 + H 2 O → Na 2 SO 4 + 2HClNaCl: 2NaCl + H 2 O + m SiO 2 → Na 2 O· m SiO 2 + 2HClIn summary, the previous studies have primarily focused on chlorine release characteristics during RDF combustion, with factors such as temperature, time, waste composition, and additives being considered. 19–23 However, there is a lack of research on the impact of RDF particle granulation on chlorine release. The MSW without granulation is loose and the contact between components is insufficient, resulting in the low conversion rate of some solid–solid reactions and gas–solid reactions.…”

“…In summary, the previous studies have primarily focused on chlorine release characteristics during RDF combustion, with factors such as temperature, time, waste composition, and additives being considered. [19][20][21][22][23] However, there is a lack of research on the impact of RDF particle granulation on chlorine release. The MSW without granulation is loose and the contact between components is insufficient, resulting in the low conversion rate of some solid-solid reactions and gas-solid reactions.…”