Valorizing organic residual streams: Roadside grass

Refining routes Municipality of Groningen

Commissioned by the municipality of Groningen, Ecoras conducted an extensive study of the processing possibilities of roadside and ditch grasses. At that time, the municipality processed the streams mostly through fermentation and composting, but much more is possible with roadside grass; high-quality alternatives.

Based on desk research and interviews, an overview of the processing possibilities was created, in which the different options were placed side by side. This revealed, among other things, that the processinge routes towards fermentation and composting are not the highest-value applications. An outlet with a cascading approach to materials (fibers) combined with VFA or biogas production emerged as the most promising option.

This option gives the most freedom of choice in both the short and long term, because it is relatively easy to switch to new – promising – applications. A municipality’s role in the production chain is an important factor in the success of alternative processing methods. From a position as, for example, client, roadside manager or buyer / launching customer of biobased products, a municipality can influence the entire process.

Assessment methodology biomass

The sustainable use of biomass in the circular economy has no standard utilization route. The combination of the motivations and interests of the actors involved and the specifics of the substances, times and location leads to appropriate, unique choices. To help the actors (owners, processors, entrepreneurs, authorities, researchers, etc.) find their way through the maze of options, Ecoras (in a consortium together with Bioclear Earth and Ekwadraat) has developed a balancing methodology.

The image of a map can be used as an illustration: the methodology does not describe the end point to be reached and the road to be followed, but helps those involved to map out their own unique route. The emphasis is on clearly describing the options with their specific pluses and minuses and on making explicit what the actors involved want and can do. In this search process, collaboration is an important aspect.

To promote the establishment of collaboration, a “tool” was developed that was tested and further developed in the elaboration of the case studies around roadside grass, greenhouse gases and sustainable area design. The method was developed specifically for biomass, but the resulting three-level approach is more broadly applicable to developing the circular economy. This document is part of this toolbox and serves as descriptive background.

Regulation of the use and exploitation of residual flows

In many places, people are working to find a way to recycle organic waste streams, such as roadside grass. In this, regulations play an important role; this can determine what is and is not possible. This is also the case with an initiative in the municipality of Súdwest Fryslân, where a local farmer wants to start a project to return local biomass flows to agriculture. The local biomass comes from various parties (such as municipalities, province, water board and farmers’ own biomass) and must be processed on the farm through a form of composting (CMC composting), so it can be put to good use on the land as a soil improver / organic matter replenisher.

In the development, the initiators run up against the fact that it is difficult to find out which rules apply, who is responsible for which rules and whether more should not be possible in the context of national developments (circular agriculture, from waste to raw materials). The municipality is willing to support this, but is still looking for a way to arrange this properly so that no problems arise afterwards.

In these projects we work together with all relevant stakeholders (environmental service, municipality, water board, initiator, platform Circular Terrain Management and Circular Friesland) to come to a suitable solution. Sometimes this means entering a permit process under the right conditions, and sometimes temporary regulatory space can be created from the experimental space.