What can a city region do to encourage the collection, recycling and reuse of both plastic and construction waste? VITO has developed an online portal that is publicly accessible and whose content can be improved or supplemented. This ‘living’ overview should prompt the city region of Ghent to take targeted actions regarding the circular economy and involve local businesses.

A while back, the City of Ghent issued a tender to analyse the potential of circular economy in the city region (Ghent together with the port area and the municipality of Destelbergen). The focus here was on two material streams: plastics and building materials. With such reporting, the streams are traditionally analysed in detail via an extensive survey and stakeholders are questioned. All the information is then incorporated into a cumbersome report.

Online overview

VITO, which has extensive experience with this type of task, decided to take a different approach this time. “We proposed to firstly bring together all our own knowledge and data, supplemented by the information we collect through our usual channels,” says Kris Broos of VITO. “We then wanted to present this information in a user-friendly format that everyone is familiar with, namely that of a wiki  (a Wikipedia page, ed.). Therefore, an online portal that is not only accessible to the public, but also invites feedback, in the form of corrections and additions.”

The proposal was well received by the City of Ghent, and the wiki has been online since last summer. “You could describe our approach as top-down,” says Ive Vanderreydt of VITO. “And it should be added that the result is transparent. Moreover, nobody feels excluded; on the contrary, the living nature of the wiki (which replaces the traditional final report, ed.) ensures that stakeholders can make additions in real time. This may in turn prompt other companies that have not yet made a contribution to participate.”

Unique at city level

According to Kris and Ive, the scale of the work is also unique. “Reports on circular economy very often cover high policy levels, such as European and Flemish, or very low, such as company level. This rarely takes place at city level.” The wiki has already produced results through this scale. For example, the graphics on the portal clearly show that the plastic waste stream in a city region only has limited potential. Vanderreydt: “The collected waste streams are too small for this. Our wiki indicates that, if you want to help close the plastic cycle, it is best to adopt initiatives at regional level. Just think of the extension of the PMD bag (for plastics, metals and drinks cartons).”

The wiki can also lead to concrete suggestions for improvement.  The purpose of the wiki is to show you how to work with a circular economy in a city region, specifically in the field of plastics and construction waste. “Circular economy is very popular nowadays, but it is also a catch-all term”, says Ive Vanderreydt. “With our wiki, policymakers at city level can identify circular ‘germs’ in the existing linear economy. They can then stimulate them.”

While the plastic stream offers few prospects for impact at city level, the opposite applies to construction waste. “Building materials and demolition waste are typically a given at local level”, says Broos. “Producers are generally in the area and with construction waste you do not have to drive to the other side of the country. Moreover, they are available large quantities in a city like Ghent – particularly if you take the port into account”.

For example, the wiki shows in a graphic how much bitumen is purchased each year, how much is on the Ghent roofs (‘in stock’), and how much is disposed of as construction waste. This graphical representation is useful for stakeholders, because it immediately clearly shows where there are possible gaps. For example, are all by-products actually included in the analysis?

CO2-negative stepping stones

Ghent would not be Ghent if the administration did not use the potential of circular economy to make the city more sustainable, with a strong focus on climate. Thus, the city wants to build a pavement this year consisting of CO2-negative ‘stepping stones’. These stones are produced according to the Carbstone process, in which building materials are made from steel slags (e.g. originating from the steel plants in the port of Ghent) and considerable quantities of carbon dioxide. With the Stepping Stone project (which is subsidised by the Circular Flanders program, and which, in addition to VITO, includes the cooperation of the City of Ghent, Orbix, Ghent University and Peter Stouthuysen, ed.), we want to make the circular economy tangible in the urban environment”, says Liesbeth Horckmans of VITO. On the one hand, we want to use this demonstration project to literally bring the people of Ghent into contact with a CO2-negative infrastructure. On the other hand, we want to learn from its practical implementation. A city administration has a lot of impetus in this area. For example, it can stimulate circular and sustainable building by prescribing it in its specifications for public works.

In the meantime, the City of Ghent wants to further stimulate the circular urban economy by means of, amongst other things, the wiki. Together with the partners of the Cleantech Cluster Regio Gent, which was founded in 2016, we want to focus strongly on a package of initiatives for the development of the circular economy in our region, in view also of the attention given to this by knowledge institutions and companies”, says Adinda Baro of Ghent Economic Services. “The analysis of plastic and building material streams is an important step. It allows us to locate gaps in the value chain, which in turn can offer opportunities to companies. In the course of 2019, we want to continue working on the establishment of specific value chains by meetings of stakeholders. At the same time, we are engaging in projects focusing on new materials and innovative forms of collection and processing, with companies from the Ghent region that show a strong interest, and with Flemish and European actors. As the Ghent region, we want to clearly show that cooperation between different partners does pay off, materials based on reuse or new compositions are reliable, and new business models can be created. In short, we want to fully assume our role as a testing ground by – amongst other things – using circular materials in buildings and infrastructure in our territory.”


Cleantech cluster regio Gent


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