Christia Meidiana, Thomas Gamse
Scavenging and composting contributes to waste reduction in Yogyakarta City. Waste reduction in composting centres and in Bendo Landfill done by the scavengers has been observed. The results showed that the recyclable material from Bendo landfill was plastics, paper, metal and glass. Waste reduction done by scavengers was about 7.5% and 12.8% for plastics and for paper respectively. Reduction on metal and glass were very small (below 0.01%) because most of the waste has been sorted by the scavengers before delivered to the landfill. Meanwhile, composting centres has reduced the organic waste from household about 10.33% of total organic waste. However, though the relatively significant waste amount reduction rate because of these two waste treatment methods, the methane emission reduction from 1993 until 2012 is inconsiderable. Without waste reduction, the methane emission is estimated about 8.78E+06 ton CO2eq per year, whereas with waste reduction, the methane emitted from Bendo landfill is estimated about 8.71E+06 ton CO2eq per year. It means that the scavenging activity and composting centers have contributed 1% reduction of methane emission. The small percentage of paper compared to that of organics waste in waste component causes the insignificant methane emission reduction in Bendo landfill, whereas the low capacity of composting centers led to slight contribution. The focus on reduction of organic component in municipal solid waste disposed of in landfill is likely to be an appropriate way to reduce methane emission from the landfill significantly.
Graz University of Technology, Department of Chemical Process and Environmental Technology, Graz, Austria; Faculty of Engineering, Brawijaya University, Malang, Indonesia
