Case Story Sweden

REVAQ Certified Wastewater Treatment Plants in Sweden for Improved Quality of Recycled Digestate Nutrients

April 2015

To ensure high quality of the digestate produced from anaerobic digestion of sewage sludge in Sweden, a certification system, called REVAQ, has been established. REVAQ is operated by the Swedish Water & Wastewater Association, the Federation of Swedish Farmers (LRF), The Swedish Food Federation, and the Swedish food retailer’s federation, in close cooperation with the Swedish Environmental Protection Agency. Today, more than 50% of the Swedish population is connected to a wastewater treatment plant (WWTP) certified through REVAQ and the number is steadily growing. The work performed by the certified WWTPs is focused on removing the sources of heavy metals and other contaminants before they reach the WWTPs, and ensuring safe recycling of nutrients to agricultural land.

The goals of the REVAQ work are to:

• avoid unacceptable accumulation of metals or undesired organic substances on agricultural land in the long term
• have no accumulation of cadmium taking place from 2025
• reduce accumulation of non-essential substances to a maximum of 0.2% per year from 2025