February 15, 2021 EnergyEnvironment

Tapping the Power of Wastewater

One third of the global population has no access to toilets or latrines, while six in 10 do not have access to safely managed sanitation facilities. Furthermore, 80% of wastewater from human activities is discharged into rivers and seas without any pollution removal, according to the latest data[1].

Yet by 2030, for compliance with SDG6, access to safely managed sanitation should be made available for all (target 6.2) and the volume of untreated, discharged wastewater should be halved (target 6.3).

These alarming facts make it hard to believe that SDG6 targets can be achieved in less than 10 years, especially given the negligible progress achieved in the past  years (fig. 1). Significant progress is still required, especially in the field of wastewater management.

Current sewage treatment systems consume large amounts of energy, estimated at between 1% and 3% of global energy output. While over 20% of municipality electrical energy consumption on public utilities is used for sewage plant operations.[2]

High capital expenses and high operational costs are major barriers to the implementation of sewage systems, particularly in low-income countries. In addition, full implementation of currently prevailing technologies would significantly increase the negative climate impacts of wastewater treatment, with a notable rise in energy consumption.

Circular economy

Alternative, more affordable and sustainable pathways are possible. In the next IWA webinar “Circular Economy: Tapping the Power of Wastewater” on 23rd February at 15:00 CET, we will demonstrate alternative solutions to reduce the energy consumption of wastewater treatment.

Two case studies of energy-positive wastewater treatment plants will be presented, namely the Copenhagen (Denmark) and Turku (Finland) plants, which use systems for harvesting the intrinsic thermal and chemical power of wastewater.

Real-life cases show that just by converting the chemical energy, twice as much energy can be supplied than consumed. While by utilising both the thermal and chemical energy, energy supply can be nine times higher than consumption. Both pathways have their benefits and limitations that need to be considered when planning facilities. However, the best practice scenarios exist for application in smaller and larger sewage plants under different, albeit moderate, climatic conditions[3].

In addition to the case studies outlined by practitioners in the webinar, students will also present their visions for energy recovery from wastewater. At the end of the presentations, a Q&A session will be held, giving the audience the opportunity to engage with the experts.

Don’t miss this opportunity to learn from real life experiences around tapping the power of wastewater. This free webinar is a practical opportunity that will help you shape a water and energy-wise world for the future!

We invite interested participants to reflect on two crucial questions which will be discussed:

  • How can we implement the presented technologies under all climatic conditions?
  • How can we use the supply of energy, cooling and heating to finance wastewater treatment in low-income countries?

We look forward to seeing you at the webinar on 23rd February, 15:00 CET – sign-up here to reserve your place.

[1] https://www.un.org/sustainabledevelopment/water-and-sanitation/

[2] Capodaglio and Olsson, 2019, Energy Issues in Sustainable Urban Wastewater Management: Use, Demand Reduction and Recovery in the Urban Water Cycle, Sustainability 2020, 12, 266; doi:10.3390/su12010266

[3] Hao et al., 2019, Energy recovery from wastewater: Heat over organics, Water Research, Volume 161, 2019, Pages 74-77, ISSN 0043-1354 https://doi.org/10.1016/j.watres.2019.05.106

Fig. 1 Number of people with and without access to safe sanitation

Ludwig Hermann

Proman Consulting, Austria