On a global scale, less than half of all wastewater is collected and less than one fifth is treated. This has led to severe environmental degradation of many inland and sea waters around the world. This white paper provides lessons learned from Danish stakeholders within wastewater treatment.
Increasing water scarcity and population growth underline the importance of treating and understanding the value of wastewater. The United Nations’ Sustainable Development Goal 6 aims to halve the proportion of untreated wastewater discharged into our water bodies by 2030. In achieving this goal, it is important also to focus on energy efficiency and energy recovery in the design of new and upgrade of existing wastewater treatment plants.
Energy producing wastewater treatment plants
The water sector accounts for approximately 4% of the world’s total electricity consumption and wastewater treatment alone accounts for a quarter of this. In Denmark, the water sector’s share of the country’s total electricity consumption has fallen to 1.9%. Most Danish wastewater treatment plants have invested in different ways to reduce their energy consumption and are increasingly focusing on energy production. As a next step, some water utilities are also looking into recovering the heat from the wastewater before it is discharged with the additional benefit of reducing the temperature impact on the receiving waters.
Using wastewater as a resource
Considering wastewater as a resource is a relatively new perspective. However, today it is widely recognised that the organic content in the wastewater can be a resource for energy production and phosphorus can be used for fertiliser production with several advantages compared to the application of sewage sludge on agricultural land. Finally, the water itself can be cleaned to such high standards that it can be reused in a number of ways – e.g. for flushing toilets, laundry machines or irrigation for crops.
Find inspiration for your own wastewater projects
This white paper features lessons learned from different Danish stakeholders within wastewater treatment. It is meant to serve as a tool for inspiration for reaping the benefits of using wastewater as a resource.