Circular water in the neighbourhood

Noardling – Desah developed and implemented a decentralised, circular wastewater treatment concept for among others (new) neighbourhoods. Within this concept we have a source separated wastewater collection and treatment system which leads to the recovery and reuse of energy, nutrients and water. The black/toilet water is collected via vacuum toilets and vacuum sewerage (and if preferred we can add green kitchen waste to this black water stream) and the grey water is collected via gravity. The two streams are transported separately to a compact, local wastewater treatment plant which is located in the neighbourhood. There the wastewater is treated on an energy efficient way and can be discharged to the surface water or, even better, being reused. This system leads to:

– 30% drinking water saving through vacuum toilets
– Local source of high-quality treated water available for reuse for irrigation f.e.
– Effective removal of micropollutants
– Processing black water produces 3x more biogas compared to traditional wastewater treatment
– Supplies 10-30% of heat/energy needed for heating of homes
– Energy positive wastewater treatment system/requires less energy
– 3x more nutrients can be recovered compared to conventional wastewater treatment
– Sewage sludge can be used for agriculture/soil improvement
– There is no sewer overflow when there is intensive rainfall
– It relieves the existing wastewater treatment system
– In terms of carbon footprint: Our source separated wastewater treatment has a 3 times lower carbon footprint if you compare it to a conventional wastewater treatment plant. This is because of biogas production, less emissions of nitrious oxide, recovery of heat and nutrient recovery (struvite and sludge which can be used as fertilizer).

We have implemented this solution for example in Helsingborg, Sweden for a new residential area called Oceanhamnen with around 1000 houses. The goal for this project was to be as circular with wastewater treatment as possible, save water and recover and reuse nutrients and energy.

In 2022 this project in Sweden won GWI’s (Global Water Intellegence) Global Water Award in the category Wastewater Project of the Year for the circular decentralised wastewater treatment solution for a new neighbourhood.