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Green walls with greywater treatment capabilities can play a key role to close water cycles in growing cities worldwide. Most green wall systems for greywater treatment apply a similar process as in constructed wetlands, where the substrate acts as plant substrate and to treat the polluted water. A novel green wall system is in development that separates the plant layer from the greywater treatment, by introducing a setup similar to a trickling filter. In a first step, various commercial substrates were tested for their suitability in terms of treatment performance at two different hydraulic loading rates over a 10-week period, using synthetic greywater. Measured parameters for determining pollutant removal were turbidity, chemical oxygen demand (COD), and others over a treatment time of seven days, measuring concentrations at the beginning, after three days and at seven days. The first substrate, expanded shale, performed best, achieving removal rates up to 60% for COD, closely followed by the other two substrates, plastic Hel-x and foam carriers. Generally, most pollutants were removed within the first three days of treatment. Even though plastic Hel-x carriers were not as efficient in pollutant removal as expanded clay, the carrier will be used for planned pilot trials of the novel green wall system due to their lower weight.

Während der Bedarf an Süsswasser weltweit stetig steigt, wird dessen Verfügbarkeit immer knapper. Um dem entgegenzuwirken, ist die lokale Behandlung und Wiederverwendung von Grauwasser ein vielversprechender Ansatz. Von besonderem Interesse sind der Einsatz von grünen Wänden, als platzsparende Alternative zu Pflanzenkläranlagen, und Filtersäulen zur biologischen Reinigung des Abwassers. Im vorliegenden Projekt wurden die Grundlagen für einen energie- und wasserautarken Waschmaschinenbetrieb, basierend auf der biologischen Reinigungstechnologie, erarbeitet. Es wurde eine Reihe von Experimenten durchgeführt, um Waschmaschinenabwasser zu charakterisieren, eine geeignete Vorreinigung auszuwählen, ein geeignetes Filtersubstrat für die grüne Wand zu identifizieren, die Keimbelastung zu analysieren und den Energieautarkiegrad zu bestimmen und zu optimieren. Die Analyse des Waschmaschinenabwassers zeigte, dass ein Grossteil der Verschmutzung im Abwasser vom Waschmittel selbst stammt. Daher ist die Verwendung eines ökologischen Waschmittels und dessen korrekte Dosierung essenziell für einen ressourceneffizienten Betrieb. Für die physikalisch-mechanische Vorreinigung wurden ein Sandfilter und ein Feinfilter getestet. Aufgrund der hohen Faserbelastung im Waschmaschinenabwasser zeigte sich der Sandfilter als ungeeignet, da er schnell verstopfte. Stattdessen konnte mit dem Feinfilter eine gute Vorreinigung erzielt werden. Die Faserbelastung im Waschmaschinenabwasser betrug durchschnittlich 25 mg/L vor der Vorreinigung und konnte durch den Feinfilter auf 2 mg/L reduziert werden. Die Analyse der Reinigungsleistung verschiedener Substrate für die grüne Wand, darunter Vulkaponic, Vulkaponic/Pflanzenkohle-Mischung und Perlit, zeigte, dass mit reinem Vulkaponic die besten Ergebnisse erzielt wurden. Die Reinigungseffizienz von Vulkaponic betrug im Durchschnitt 85%, während die Mischung aus Vulkaponic und Pflanzenkohle eine Reinigungsleistung von 78% aufwies. Perlit erreichte eine Reini

Aquaponic food production requires a broad spectrum of knowledge in order to understand and manage the processes involved, and for commercial aquaponics to develop its full potential, it will require an appropriately trained workforce. Devised in collaboration as an Erasmus+ Strategic Partnership for Higher Education, Aqu@teach covers the basics of aquaponics with a focus on transferable and entrepreneurial skills. The aquaponics curriculum can either be taught using blended learning - combining digital media and the internet with classroom formats that require the physical co-presence of the teacher and students - or as an e-learning course. The supplementary entrepreneurial skills module was devised on the basis of two surveys: of aquaponics companies around the world, in order to get a broad overview of the skills that are important in the early years of a business; and of European higher education institutions that teach subjects where aquaponics could be incorporated as an optional module. The entrepreneurial skills curriculum introduces the main processes involved in developing a business idea into a start-up company. All of the Aqu@teach resources - the e-learning modules, textbooks, module guides for students, curriculum guides for teachers, best practice guide for teaching aquaponics, and toolbox of innovative didactic practices - are open access.

In the scope of this study, a pilot facility for the recycling of laundry effluent was developed and tested. With the aim to enable nearly complete energy and water self-sufficiency, the system is powered by a photovoltaic plant with second-life batteries, treats the wastewater within the unit and constantly reuses the treated wastewater for washing in a closed cycle. The technology for wastewater treatment is based on a low-tech approach consisting of a physical/mechanical pre-treatment and biological treatment in trickling filter columns. The treatment process is operated in batch mode for a capacity of five washing cycles per day. During five weeks of operation water quality, energy consumption and production, water losses and washing performance were monitored. The system recovered 69% of the used water for the washing machine while treating the wastewater to the necessary water quality levels. The average COD removal rate per cycle was 92%. Energy analysis was based on modelled data of the monitored energy consumption. With the current set-up, an internal consumption rate of 80% and self-sufficiency of 30% were modelled. Future developments aim at increasing water and energy self-sufficiency and optimizing the water treatment efficiency.

Aquaponic food production requires a broad spectrum of knowledge in order to understand and manage the processes involved, and for commercial aquaponics to develop its full potential, it will require an appropriately trained workforce. Devised in collaboration as an Erasmus+ Strategic Partnership for Higher Education, Aqu@teach covers the basics of aquaponics with a focus on transferable and entrepreneurial skills. The Aqu@teach Textbook forms the basis of the curriculum.

While globally freshwater is becoming an increasingly scarce resource, the local treatment and reuse of greywater is a promising approach to address water scarcity. In the scope of this study, a pilot facility for the recycling of laundry greywater has been examined. With the aim to enable nearly complete energy and water self-sufficiency, the system treats the wastewater within the unit and constantly reuses the water for washing in a closed cycle. The system is based on physical/mechanical pre-treatment and biological treatment in trickling filter columns. The treatment process is operated in batch mode. Furthermore, the facility is powered by a photovoltaic plant (0.9 kWp) with second-life batteries (4 kWh). The facility is designed for up to five washing cycles per day, producing approximately 300 l of wastewater per day. The facility has been operated during an experimental period of ten weeks. Parameters for energy consumption and production, water losses, and water quality were monitored. First results indicate that the system achieved to recover 69% of the used water for the washing machine while treating the wastewater to the necessary water quality levels. Most of the water (26%) was lost in the pre-treatment step due to the skimmer. Therefore, further development will aim to treat the skimmer wastewater and feed it back into the system. By doing so, water self-sufficiency could reach up to 90%. Furthermore, energy self-sufficiency and optimization measures were modelled for one year based on the monitored data from the ten week experiment.

Aquaponics plays a part in promoting sustainable development on different levels in society, and its use is becoming ever more widespread. However, there are not enough trained specialists yet to build and operate such systems. The aim of this paper is to highlight the role of institutions of higher education – like ZHAW – can play to mitigate this deficit. ZHAW has the ability to execute applied research, teaching on BSc and MSc level, and is aiming to increase societal added value concerning education and health. Each of these levels has different demands on the aquaponic system concerning a multitude of factors, such as access, size, construction, climate control, diversity of production methods, recycling and closed loop systems, provision of energy from renewable sources and rainwater harvesting, treatment and use. To evaluate how these objectives are reached, the requirements on the system originating from each level are defined. These are used to evaluate the aquaponic system that was built and operated at ZHAW. Other aquaponic systems in use are compared to the ZHAW system, using the same evaluation criteria. The results show that the ZHAW Aquaponics Lab can reach all target levels, if the aquaponic farm of its spin-off company UrbanFarmers is viewed as an extension of it.