WASTES OF MULTILAYER CONTAINERS AS SUBSTRATE IN COMPOSTING PROCESSES

An evaluation of the influence and degradation of ground multilayer co ntainers, such as Tetra Brik Aseptic (TBA), in the composting process of municipal solid wastes (MSW) is presented. Two composting piles wer e formed by mixing, in different proportions, an organic fraction of M SW and TEA material ground as flakes or stripes. Piles were periodical ly aerated by mechanical mixing. Evolution of the composting was follo wed by frequent measurements of suitable parameters such as temperatur e, moisture, ashes, total organic carbon (TOC), nitrogen, C/N ratio, p H, conductivity, nutrients, and heavy metals. As expected, aluminum an d polyethylene films from TEA were not degraded during the processes, but the cardboard fraction of TEA showed a partial decomposition that was more intense in the material ground as flakes. After two months of curing, the composts were refined and analyzed to determine their nut rient and heavy-metals contents. Despite their poor aesthetic properti es, mainly resulting from the presence of little pieces of plastic and aluminum films, the composts contained the required amounts of nutrie nts; furthermore, their heavy-metals content was below the limits prop osed by some official European organizations.