Mariel Perez Zabaleta is a researcher at DTU in Denmark who held a WaterCentre@KTH lunch seminar on 18 November 2024.
It has been a pleasure to return to KTH and present my current research topic. After completing my doctoral studies and two postdoctoral research projects at KTH, including the most recent one on SARS-CoV-2 monitoring in wastewater, it is exciting to share my latest work on water reuse in the food industry. This new topic is closely linked to my previous research, as both focus on WASTEWATER, our precious resource!
As we approach 2030, the world faces a serious water shortage, with a projected deficit of over 40%. This makes it crucial to adopt sustainable water practices and reuse water wherever possible. Shockingly, 80% of wastewater is released back into the environment without proper treatment. This not only wastes our valuable “Blue Gold” but also pollutes our planet with high loads of nutrients, chemical pollutants, drugs, microplastics, microorganisms, and more. This pressing issue was the focus of the recent seminar titled “Wastewater as a Resource: Transforming Industrial Water Use,” which highlighted the critical role industries play and the potential of wastewater reuse.
Globally, industry accounts for 19-22% of freshwater withdrawals, yet only a mere 2.4% of this water is reused. In Europe, the industrial sector consumes approximately 40% of all freshwater resources, with countries like Sweden consuming more than 60% (Figure 1). By reducing, reclaiming, recycling, and reusing water, we can significantly improve our water management practices.
Figure 1. Industrial water withdrawals in Europe. Data source: World Bank
The seminar placed a spotlight on the food industry, which has a huge impact on our water resources. Did you know that producing just one kilogram of meat can take up to 15,500 liters of water? This shows how big the food industry’s water footprint is and why it is so important for this sector to adopt smarter water use practices, like reuse, reduction, and recycling.
However, making water reuse a reality in industries isn’t without its challenges:
- Legislative Framework: Current regulations might not fully support or encourage water reuse.
- Knowledge of Hazards: It is crucial to understand and map out potential chemical and microbial hazards in treated water to ensure it is safe.
- Robust Treatment Systems: We need effective water treatment systems that can consistently produce safe, reusable water.
The seminar also introduced the “Water-for-Purpose” concept. This means treating and recycling water based on its intended use. For example, water used in cooling towers can be recirculated after less intensive treatment. It is also important to keep different types of water separate (e.g., black water should not mix with grey water) to prevent contamination and ensure efficient treatment.
By addressing these challenges and adopting innovative practices, industries can turn wastewater into a valuable resource, helping to conserve our precious “Blue Gold” and protect the environment.