Pilot 2: Water Reuse and Nutrient Recovery in Marche
Wastewater and organic residues coexist with seasonal demand for water and nutrients. Circular use requires treatment, distribution, appropriate quality, receiving users and clear responsibilities.
The Marche pilot connects wastewater management with water reuse and the investigation of recovered nutrient-bearing materials. Its two main value chains address additional water resources for agriculture and ecosystem restoration, and the potential agricultural use of materials obtained from sewage sludge.
The water pathway develops a treatment sequence combining prefiltration, a horizontal-flow constructed wetland and a free-water-surface wetland. The design addresses further treatment of Brodolini wastewater-treatment-plant effluent, with the Sentina reserve and surrounding irrigation needs providing the application context. Water-balance work quantifies the gap between demand and existing canal supply, while the treatment programme defines the quality parameters to be monitored.
The nutrient pathway combines thermochemical treatment with physicochemical characterisation and agronomic experiments. A six-treatment lettuce trial compares the recovered material with mineral fertilisation and reduced-fertiliser combinations. Incubation experiments and material analyses add information on soil behaviour, carbon mineralisation and composition.
The pilot also examines regional organic-residue availability for anaerobic co-digestion. Together, these activities connect resource inventories, treatment design and controlled testing. Construction, procurement and operational validation remain part of the ongoing programme, with each application evaluated through its own technical and regulatory requirements.
Water monitoring combines flow quantities with organic load, suspended solids, nutrients, turbidity, salinity and microbiological quality. The water balance distinguishes irrigation from pond-restoration demand and identifies the additional resource requirement to be addressed.
Nutrient-recovery assessment combines material composition and surface characterisation with soil incubation, plant growth, SPAD measurements, biomass and plant nutrient analysis. Comparators include untreated soil and full mineral fertilisation. The co-digestion feasibility work uses feedstock inventories and mass and energy balances to compare potential mixtures. These complementary methods distinguish design estimates and experimental observations from future operating performance.
Wastewater and organic residues coexist with seasonal demand for water and nutrients. Circular use requires treatment, distribution, appropriate quality, receiving users and clear responsibilities.
Marche combines a planned nature-based water-refinement system with thermochemical research on sludge-derived materials. A water-balance scenario supports reuse planning, while incubation and pot trials investigate agricultural applications.