The circular city was the theme this year of KWR’s stand at the Aqua Trade Fair Netherlands. The world is urbanising at a rapid pace, so that many of the future transition processes will take place within urban settings. Water is a connecting factor in the circular city: drinking water, sewer systems, wastewater, energy, transport, nature and people.
The challenge of achieving liveable and attractive cities is, to an important degree, related to how well we handle our water. Through research into areas like the reuse of resources from wastewater, adaptation to climate change, energy extraction from drinking water and wastewater, new sewer system concepts, subsurface water and energy storage, and the role of water in the hydrogen economy, KWR is developing the knowledge to shape the ‘water-wise city’.
TKI Water Technology
The KWR stand presented five TKI Water Technology projects associated with the central theme, in which the partnership between knowledge institutions and market players is repeated highlighted:
The availability of sufficient protein for human and animal consumption presents a growing global challenge over the decades to come. ‘Power-to-Protein’ produces high-quality protein from the residuals from the urban watercycle.
2. Green-blue roofs
Cities all over the world are seeking solutions to flooding and heat stress. Green roofs offer an attractive option. The project focuses on a lightweight, self-supporting, green-blue roof system for the storage of precipitation and urban cooling through evaporation.
3. Geothermal energy at Lelystad Airport
On the basis of the 2015 Airport Decree, Lelystad Airport will grow and develop on what is essentially a ‘greenfield’ site. The project studies the functions of the subsurface in the development of the area: besides the storage of rainwater and the provision of fire-fighting water, geothermal energy is one of the key subsurface functions.
4. Multi-source drinking water provision
The production of drinking water is typically connected to a specific source, such as groundwater or surface water. In the multi-source concept the ambition is to locally produce drinking water of impeccable quality, regardless of the source. The key technique applied is membrane filtration (reverse osmosis, or RO).
5. Circular water provision for greenhouse horticulture
As of 1 January 2018, new regulations on plant protection products will apply to the greenhouse horticulture sector: all growers will have to treat the discharge waters from their operations. The project can provide horticultural firms with an individual treatment system or, alternatively, provide several companies with a collective system.
More ‘water in the circular city’
The hydrogen economy also received attention: in an all-electric future, with renewable energy sources (solar, wind, blue energy), hydrogen has a role to play as an important energy carrier. Through electrolysis of water, electrical energy is transformed into hydrogen during off-peak consumption periods; then, depending on need, a fuel cell is later used to produce green power from the hydrogen. KWR also developed the City Blueprint as a tool for assessing the urban watercycle as a whole. This quick scan has already been applied to 45 cities and regions in 27 countries. At a single glance, one can pinpoint the most important challenges in an urban watercycle.
Workshops and presentations
For the third time in a row, KWR and Netwerkgroep Industriewater organised the workshop on ‘Emerging Technologies’ for industrial water treatment. Tessa van den Brand spoke about VibroCav, a sludge decomposition technology. Jos Boere gave a lecture to the plenary symposium on the subject of water in the circular economy, in which he stressed that the water sector has a natural leadership role in the development of this economy. And Marcel Paalman talked about circular water provision in greenhouse horticulture.