Characterization and Comprehensive Utilization Analysis of Exploited MSW Based on Landfill Sustainability

摘要

A closed and well-stabilized landfill unit was selected as a research target for the analysis of landfill sustainability. In-situ air dewatering (IAD) and mechanical vibration sieving were performed on exploited wastes buried for various landfill years. Combustible materials, fine residues, and inorganic materials are the three primary recyclable components of the exploited wastes. Moisture can be removed more easily from wastes with higher landfill age, and more fine components (oversize and undersize products of 7 mm denoted as OP7 and UP7, respectively), can be obtained after IAD and a screening process. These pretreatments are beneficial to waste recycling. Moisture content decreases by 15%-20% after IAD, and UP7 content increases to 30%-36% after the IAD and screening pretreatment of well stabilized wastes. With pretreatment, the calorific value of mixed combustible components from the exploited wastes (>5 landfill years) increases to 16750-18720 kJ/kg. Therefore, given a stabilized landfill unit, a sustainable landfill model can be realized through the process of exploitation, IAD, mechanical sieving or screening, and recycling.