BIOGEOCHEMICAL AND MECHANICAL CHARACTERIZATION OF THE LANDFILL FRACTION GENERATED BY MECHANICAL WASTE SORTING

When resource recovery from mixed waste streams is performed, new mixed waste streams are generated. Some of these waste streams does not fit well to existing waste management options, for example, they may hold a to low heating value to sustain combustion and they may have a too high carbon content to be accepted at non-hazardous landfills. Also various health and pollution risks may arise as well as practical handling issues due to the physical properties of such wastes. One such waste is the under sieve fraction generated when recovering metals and fuel from mixed waste streams using mechanical and magnetic separation tools. In this work, we examine the properties of one case of mechanical sorting of such under sieve fraction and analyse a broad spectrum of chemical, physical, and mechanical properties as well as some biological. Based on the data we develop recommendations for landfilling, what potential problems might arise and how to counteract them. The content of organic carbon and some trace elements is fairly high, but the biodegradability of the organic content is low and transports of water is also low in the material, especially after compression. We tested a range up to 700kPa. When building a mono fill with this material a special care should be given to dewatering the interior of it to avoid the buildup of water pressure. In summary we think that this material can be safely landfilled.

Automated summary

Resource recovery from mixed waste streams generates new mixed waste streams which may not fit well to existing waste management options. One type of such waste is the under sieve fraction generated when recovering metals and fuel. Despite high organic carbon content and some trace elements, this material can be safely landfilled with special care given to dewatering the interior to avoid water pressure buildup.