For reasons of hygiene, organic waste in households is often collected in customary plastic bags and then thrown into the collection bins inside these bags. Since ordinary plastic does not disintegrate during composting, it visibly taints the compost produced. Even small amounts of plastic by weight lead to so much tainting that the compost cannot be marketed. One possibility to avoid this problem is the use of waste bags made of biodegradable plastic (bdp). Alternatively, there are technical measures to remove plastic residue from the compost such as wind-sifting. The aim of this thesis was to evaluate the practicability and the economic and ecological cost of using biodegradable plastic bags (bdpb’s) in the collection of organic waste in households or wind-sifting of compost as a way to reduce the amount of plastic residue in compost. A composting plant in Bitterfeld, which operates with open, naturally aerated compost heaps, was taken as an example for the investigations here. It was analysed, if the mechanical stability of bdpb’s is sufficient for collecting organic waste in households. Also, their disintegration in compost heaps under routine operating conditions was followed. Furthermore, in concurrent laboratory experiments it was studied, whether disintegration is due to biological or just chemical and physical processes. Finally, the economic and ecological sense of using bdpb’s or wind-sifting was compared to the present mode of collecting and composting organic waste, to direct disposal in landfills and to incineration. |