Abstract: The character of mineralized aged refuse in a landfill in southwest was researched. The separation experiments of mineralized aged refuse from different landfill depths of five to thirty meters and landfill age of four to twenty-six years was carried out. It was concluded that with the increase of landfill age, the kitchen waste organic matter had been completely decomposed, the overall calorific value of stale waste decreased, the proportion of humus soil with rich microbial community increased, and the calorific value of material on the sieve with particle size greater than or equal to 40 mm was the highest. According to the characteristics of different components of the mineralized stale waste after separation, combined with the actual situation of the landfill, the combined separation process of two-stage screening, gravity separation and magnetic separation was proposed. And the best combination method of resource utilization of different materials after separation was suggested.

Key words: stale waste, mineralized, sorting, humus soil