Sustainable decentralized food waste composting using a pulse alternating ventilation pilot-scale device: Case study...

Currently few efficient decentralized composting reactors have been developed, and there is also little exploration into their comprehensive environmental impact and carbon emissions. This study developed a continuous pulse alternating ventilation composting pilot device, SC-PAVCR. Results demonstrated that SC-PAVCR effectively maintained the thermophilic phase during the 120-day operation period. The organic matter degradation degree reached 44.05 %, and the humic acid content increased to 91.21 g·kg^-1, accounting for 0.53 of the total organic carbon. Life cycle assessment analysis with windrow composting and machine composting revealed that SC-PAVCR reduced the normalized comprehensive environmental impact by 49 % and 25 %, respectively. The carbon emission intensity of SC-PAVCR was 44.3 kg CO₂ eq per tonne of food waste, representing a reduction of 26 % and 48 % compared to the other two technologies. The economic cost of $1.91-3.98/FU was reduced. These findings provide technical guidance for the development of low-carbon food waste composting technologies.