Suchergebnisse

Environmental policies in the European Union focus on the prevention of hazardous waste and aim to mitigate its impact on human health and ecosystems. However, progress is promoting a shift in perspective from environmental impacts to resource recovery. Municipal solid waste incineration (MSWI) has been increasing in developed countries, thus the amount of air pollution control residues (APCr) and fly ashes (FA) have followed the same upward trend. APCr from MSWI is classified as hazardous waste in the List of Waste (LoW) and as an absolute entry (19 01 07*), but FA may be classified as a mirror entry (19 0 13*/19 01 14). These properties arise mainly from their content in soluble salts, potentially toxic metals, trace organic pollutants and high pH in contact with water. Since these residues have been mostly disposed of in underground and landfills, other possibilities must be investigated to recover secondary raw materials and products. According to the literature, four additional routes of recovery have been found: detoxification (e.g. washing), product manufacturing (e.g. ceramic products and cement), practical applications (e.g. CO2 sequestration) and recovery of materials (e.g. Zn and salts). This work aims to identify the best available technologies for material recovery in order to avoid landfill solutions. Within this scope, six case studies are presented and discussed: recycling in lightweight aggregates, glass-ceramics, cement, recovery of zinc, rare metals and salts. Finally, future perspectives are provided to advance understanding of this anthropogenic waste as a source of resources, yet tied to safeguards for the environment.

Almost 500 municipal solid waste incineration (MSWI) plants in the EU, Norway and Switzerland with a capacity of about 90.2 Mt/a, generate 17.6 Mt/a of incinerator bottom ash (IBA). This solid residue contains minerals and metals, whereas metals are mostly separated and sold to the scrap market and minerals are either disposed of in landfills or utilised in the construction sector. Since there is no uniform regulation for IBA utilisation at EU level, countries developed own rules with varying requirements for utilisation. The work at hand provides an up-to-date overview of documents regulating IBA utilisation in the investigated countries and highlights the different requirements that have to be considered. Overall, 51 different parameters for the total content and 36 different parameters for the leaching content are defined. In order to assess the leaching behaviour nine different leaching tests, including batch tests, up-flow percolation tests and one diffusion test are in place. An analysis of the weighting of each parameter relative to the totally generated IBA is expressed by a relevance level. The analysis indicates for leaching parameters average relevance levels of 36 wt.% and for total content parameters average relevance levels of 17 wt.%. This means for a significantly larger share of the entire generated IBA leaching parameters are more to be considered compared to total content parameters. A further discussion of leaching parameters showed that certain countries took over limit values initially defined for landfills for inert waste and adopted them for IBA utilisation. It was found that 18% of all defined leaching limit values for utilisation match exactly the limit values for landfills for inert waste, 19% are stricter and therefore 63% of the values are less strict than the leaching limit values for landfills for inert waste. The overall utilisation rate is approximately 53 wt.%. It is revealed that the rate of utilisation does not necessarily depend on how well regulated IBA utilisation is, but rather seems to be a result of political commitment for IBA recycling and economically interesting circumstances.

Almost 500 municipal solid waste incineration (MSWI) plants in the EU, Norway and Switzerland with a capacity of about 90.2 Mt/a, generate 17.6 Mt/a of incinerator bottom ash (IBA). This solid residue contains minerals and metals, whereas metals are mostly separated and sold to the scrap market and minerals are either disposed of in landfills or utilised in the construction sector. Since there is no uniform regulation for IBA utilisation at EU level, countries developed own rules with varying requirements for utilisation. The work at hand provides an up-to-date overview of documents regulating IBA utilisation in the investigated countries and highlights the different requirements that have to be considered. Overall, 51 different parameters for the total content and 36 different parameters for the leaching content are defined. In order to assess the leaching behaviour nine different leaching tests, including batch tests, up-flow percolation tests and one diffusion test are in place. An analysis of the weighting of each parameter relative to the totally generated IBA is expressed by a relevance level. The analysis indicates for leaching parameters average relevance levels of 36 wt.% and for total content parameters average relevance levels of 17 wt.%. This means for a significantly larger share of the entire generated IBA leaching parameters are more to be considered compared to total content parameters. A further discussion of leaching parameters showed that certain countries took over limit values initially defined for landfills for inert waste and adopted them for IBA utilisation. It was found that 18% of all defined leaching limit values for utilisation match exactly the limit values for landfills for inert waste, 19% are stricter and therefore 63% of the values are less strict than the leaching limit values for landfills for inert waste. The overall utilisation rate is approximately 53 wt.%. It is revealed that the rate of utilisation does not necessarily depend on how well regulated IBA utilisation is, but rather seems to be a result of political commitment for IBA recycling and economically interesting circumstances.

Almost 500 municipal solid waste incineration plants in the EU, Norway, and Switzerland generate about 17.6 Mt/a of incinerator bottom ash (IBA). IBA contains minerals and metals. Metals are mostly separated and sold to the scrap market and minerals are either disposed of in landfills or utilised in the construction sector. Since there is no uniform regulation for IBA utilisation at EU level, countries developed own rules with varying requirements for utilisation. As a result from a cooperation network between European experts an up-to-date overview of documents regulating IBA utilisation is presented. Furthermore, this work highlights the different requirements that have to be considered. Overall, 51 different parameters for the total content and 36 different parameters for the emission by leaching are defined. An analysis of the defined parameter reveals that leaching parameters are significantly more to be considered compared to total content parameters. In order to assess the leaching behaviour nine different leaching tests, including batch tests, up-flow percolation tests and one diffusion test (monolithic materials) are in place. A further discussion of leaching parameters showed that certain countries took over limit values initially defined for landfills for inert waste and adopted them for IBA utilisation. The overall utilisation rate of IBA in construction works is approximately 54 wt.%. It is revealed that the rate of utilisation does not necessarily depend on how well regulated IBA utilisation is, but rather seems to be a result of political commitment for IBA recycling and economically interesting circumstances.