Sustainable secondary aggregates IBA

GRANOVA is a quality-controlled secondary construction material whose original basis is municipal solid waste. In Germany, household waste that cannot be recycled is mostly treated in waste incineration plants. The thermal recycling process generates energy and reduces the amount of waste to about one third of the original quantity. Overall, this results in several million tonnes of incinerator bottom ash per year, which are processed in appropriate recycling plants and then reused as secondary aggregate. GRANOVA is a quality-controlled incinerator bottom ash aggregate that is produced and delivered only by selected and certified companies of the REMEX Group.

From waste to construction material

The bottom ash that remains after the incineration of municipal solid waste in Energy-from-Waste (EfW) plants (also: Waste-to-energy plants) is treated in one of REMEX’ recycling plants. After the raw ash (also: grate ash) has been processed, it is referred to as incinerator bottom ash (IBA) or incinerator bottom ash aggregate (IBAA) respectively. Within the industry, the term slag instead of ash is sometimes used as an alternative expression.

The raw ash from municipal solid waste incineration (MSWI) is essentially processed by classifying the mineral fraction and separating ferrous metals and non-ferrous metals as well as organic matter. After three months of storage during, GRANOVA IBA meets the German environmental requirements for use as substitute construction materials. Due to its composition, GRANOVA is a high-quality alternative to natural aggregates.

From waste to secondary aggregates: incinerator bottm ash recycling

The actual areas of application result from national and international regulations

Main fields of application of IBA

Processed incinerator bottom ash can be used as aggregate in road construction and earthworks in accordance with the German Secondary Aggregates Directive. The main areas of application include:

  • Noise protection barrier
  • Dam
  • Backfill, embankment, bridge ramp
  • Subgrade
  • Subbase, e.g. frost blanket course of selected load classes
  • Base and lower base course of selected load classes

In addition, IBA is used in construction measures at landfill sites. This use as landfill construction material is subject to the requirements of the German Landfill Directive.

Fields of application for incinerator bottom ash include roads, earthworks, landfills, asphalt and concrete

The use of incinerator bottom ash has also long been proven in the production of concrete products and blocks. Due to the current German regulations, however, this opportunity cannot be implemented in this country. In other European countries, including the Netherlands with model character, the use has been permitted for many years and is supported by the public sector. We advocate to adapt the national and international framework for recycled concrete to state-of-the-art knowledge by including IBA, so that a more sustainable concrete production is generally made possible. In doing so, we draw on the experience of our Dutch subsidiary HEROS Sluiskil B.V.

Click here to find out more about the application areas of GRANOVA