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CSR 2016 – boskalis
In 2016 Boskalis Environmental and HVC, the largest non-commercial waste collection
company in the Netherlands, opened the world’s first bottom ash washing plant. The
plant recycles incinerator bottom ash, a by-product of the incineration of household
waste in waste-to-energy plants.
For many years this contaminated bottom ash could only be used as a building
material in the Netherlands if stringent conditions were met, with the material having
to be sealed in sheeting to prevent pollutants leaking into the environment. However,
the use of incinerator bottom ash required such an intensive and expensive management
program by the Dutch government that it will be banned.
Boskalis Environmental developed its own patented separation and flushing
technology and offers a unique sustainable method of cleaning incinerator bottom
ash. Once processed, almost all of the bottom ash is suitable for re-use as a raw
material, allowing Boskalis to contribute to the circular economy. Haico Wevers,
director of Boskalis Environmental: “The mineral fraction, consisting of sand and
granulate, will be used as a freely applicable building material in Boskalis’ civil
engineering works while the valuable and rare metals can be marketed as
commodities by the waste-to-energy plants.”
The Netherlands has twelve waste-to-energy plants and they produce approximately
two million tons of bottom ash annually. “Cleaning and processing the incinerator
bottom ash is a fine example of the circular economy. The plant fulfils the Green Deal
that the government has with the waste-to-energy sector,” points out Dion van Steensel,
director of HVC. “The agreement is that 50% of all processed bottom ash must be
re-used sustainably by 2017, rising to 100% in 2020.”
At the beginning of 2017 Boskalis announced, together with Inashco, that it will process
all bottom ash produced by Attero’s waste-to-energy plants in the Netherlands for a period
of ten years. A new state-of-the-art plant at Nauerna in the Port of Amsterdam area will
process the bottom ash.
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“Cleaning and processing
the incinerator bottom ash
is a fine example of the
circular economy.”