Roadside grass as a green raw material

In the Netherlands, around a million tons of grass per year is mowed from road verges, and the clippings can be very valuable. On the Board’s initiative, the Port of Amsterdam, biobased resource company NewFoss, the Ministry of Infrastructure and Water Management, the Province of Noord-Holland and the Zuiderzeeland Regional Water Authority are collaborating on the intelligent use of grass clippings in the project GrassBloxxx. How much grass is processed, and what is the output?

Each year in our region, more than 50,000 metric tons of road verge grass clippings and green waste is collected during the construction and maintenance of road verges, drainage canal banks, public green space, and woodland and nature areas (link is in Dutch). The clippings and green waste has the potential to be a valuable resource – even a replacement for oil as a raw material for intermediate goods and finished products. Large volumes are needed to make this valorisation economically viable, so a number of grass clipping suppliers are needed to make business cases profitable. At the same time, it is important that all parties that stand to benefit from the development of this new chain, from clippings to product, start the preparation of business cases at an early stage and make a long-term commitment.

Volume through collaboration

The Province of Noord-Holland, the Ministry of Infrastructure and Water Management and the Zuiderzeeland Regional Water Authority can each supply an estimated 10,000 to 30,000 tons of grass clippings per year in the Amsterdam Metropolitan Area. Some municipalities are also interested, and can supply an estimated 400 to 2,500 tons of clippings per year. For valorisation to produce raw materials using the technology applied by NewFoss, a constant input of 50,000 tons of material per year is needed – a perfect match with the available supply. After introductions and a preparatory period, during which the Amsterdam Economic Board supported the various parties in the chain in specifying the terms for collaboration, confirmed by a Letter of Intent, at the end of last year, the project got underway.

Paper and insulation material

The partners are working on a business case for the construction of a factory to sustainably process grass clippings. The consortium will harvest 50,000 tons of clippings and process it into fibre that can be used to make insulation material, for example, or paper, thus reducing the use of new plant material and oil. In addition, the sap will be used to produce biogas. In the future, possibilities will also be explored to extract minerals from the sap to make anti-icing fluid as a replacement for brine.

Research and business case: in autumn 2018 we’ll know more

The focus of the research currently lies on production, at the front end of the process: what is the best way to mow the grass, how can the best quality be conserved, and how can we transport it to the factory? Research will then be conducted on the back end of the process: who will purchase the processed clippings (either as a fibre or finished product)? In the autumn of 2018, new figures are expected on the basis of the research and the preparation of the business case. The figures will be used in decision-making on investment.

Role of the Board

The Amsterdam Economic Board helped to set these developments in motion by conducting thorough market research and bringing together the parties concerned within the scope of the Board’s material transition programme. This is the collaborative programme in which waste streams are combined and upgraded at the scale of the Amsterdam Metropolitan Area to create new material streams. 

In particular, an essential aspect of the Board’s role was to make contacts and work on negotiations for a partnership between grass clipping suppliers, the Port of Amsterdam, the processor and the purchasers of high-grade finished products.

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This is part 3 of a series of articles on the Amsterdam Metropolitan Area’s material transition programme.

Source: Micha Hes – Port of Amsterdam

Photo by Lloyd Morgan, via Flickr (Creative Commons)

10 July 2018

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