Resource recovery from wastewater treatment: Effects of water reuse and slow-release fertilizers on faba bean within Palermo University (Italy) case study

The wastewater treatment plants (WWTPs) must be transformed into Water Resource Recovery Facilities (WRRFs) in view of a more sustainable approach focusing on the circular economy concept. Different to WWTPs, the WRRFs have as a major goal not only the wastewater treatment to meet the legislation limits but also the recovery of resources such as: treated water for water reuse, carbon, nutrients, biopolymers etc. In view of boosting the WRRFs application in the real WWTs, a WRRF at Palermo University (UNIPA) has been built within the EU project: Achieving Wider-Uptake of Water Smart Solutions. This study is aimed to demonstrate the feasibility of resource recovery from wastewater treatment at UNIPA WRRF. Specifically, the effects of treated wastewater (TWW) and recovered nutrients from wastewater on faba bean were assessed. Results showed that treated water aligned with EU legislation. Further, TWW increased soil electrical conductivity and adversely impacted plant growth. However, the application of biochar and zeolite effectively mitigated these adverse effects. Microbiological investigation revealed that both broad bean pods and seeds analysed did not host pathogenic bacteria.