From Wastewater Treatment Plants to Resource Plants
The transition to a circular economy is crucial in building a sustainable society. Today, almost half of our climate impact and 90 percent of water scarcity issues are linked to the way we extract resources and produce goods and food.
In this context, nutrients such as phosphorus and nitrogen are key. Without them, global agricultural output would be cut in half. Wastewater from households and industries contain massive amounts of both phosphorus and nitrogen, but today, this is a problem rather than an asset. Wastewater treatment plants put great effort into discarding sludge even though this sludge is rich in phosphorus, and nitrogen is released from the plants as nitrous oxide (N20) which has a huge climate effect.
With a different approach, the opportunities are enormous. Phosphorus, listed by the EU as a critical raw material, can be recovered from the sludge and brought back into the loop, securing an endless supply. Nitrogen can be captured from wastewater streams and used to produce fertiliser, replacing today’s greenhouse gas-heavy production.
This way, the wastewater treatment plants of today will be the resource plants of tomorrow.
This scenario is well within reach. However, it requires key alterations in national and international legislation and regulation.
Proposals in short
- Governments should change the stated purpose of urban wastewater treatment plants, making the enabling of increased circularity a main objective.
- Governments should task a national authority with coordinating control at source of hazardous substances and providing a central function for know-how and active support on issues around wastewater and resources.
- Governments should, at the appropriate level, strive to introduce legislation on quota obligations for commercial fertiliser, requiring an increasing percentage of phosphorus and nitrogen in the products to be of secondary origin.
- Governments should introduce legislation on milestone targets for the recycling of phosphorus and nitrogen from wastewater for agricultural purposes.
- Governments should strive to introduce legislation on requirements for the assessment and limitation of nitrous oxide (N20) emissions from wastewater treatment plants.
- Governments should allocate funds for full-scale pilot facilities for extracting nitrogen from wastewater with the explicit purpose of producing raw material for fertiliser production.
- Governments should strive to increase incentives for a transition to circular handling of key resources, specifically by ensuring that the quality of the product should always be the key regulatory factor and not its origin.
Lars Lindén, CEO at Ragn-Sells
Jan Svärd, CEO at EasyMining
Pär Dalhielm, CEO at Svenskt Vatten (Swedish Water)