Danish know-how extracts dollars from American ash

Denmark – Getting ferrous and non-ferrous metals from waste-to-energy (WtE) ash is a growing business around the world. It is also a fast-evolving business in technology terms, with ever more powerful magnets being developed and more elaborate systems designed every year.

Meldgaard of Denmark, which has been in this business area for more than 20 years, has expanded its activities into the USA. In Europe, the bottom ash is kept separate from the fly ash whereas America’s WtE ash is typically combined, leading to ash recycling challenges when dealing with the lime content of the fly ash.

Meldgaard now has three operating ash recycling plants in the USA, each one of which is distinct because the ash differs from plant to plant. In addition, each facility is processing ash at a different stage in the ash handling process, either directly from the plant without any buffer storage through to processing on monofills with ash being stockpiled for several weeks.

The company′s latest ash recycling plant is integrated into the ash handling system of the WtE plant such that there is no interference in the removal of ash for disposal. People in trucks loading the ash are unaware that Meldgaard has already extracted the valuable metals from it to share with the WtE plant operator.

This was no easy task given that 500 tonnes of ash is delivered daily by conveyor straight from the WtE plant to Meldgaard′s feed hopper. That ash is still moist and fresh from the ash bunker, making it difficult for current US recyclers to process. ′However, we were able to develop a unique system for the ash processing which means we are now extracting record levels of non-ferrous metals,′ Meldgaard explains.

For more information, visit: www.meldgaard.com