Talavera de la Reina

Location: Talavera de la Reina Wastewater Treatment Plant.

Climate:The city experiences a Continental climate, characterised by hot, dry summers (often exceeding 35°C) and mild, wet winters (below 10ºC).

Context: Talavera de la Reina is an urban area with ~83,000 inhabitants that sits at the bank of the Tagus River. In collaboration with local authorities, FCC Aqualia has been implementing different Nature-based Solutions (NbS) for improving municipal wastewater treatment sustainability.

Typology: Vertical Flow Constructed Wetland (VFCW) for municipal wastewater treatment.

Description: Urban Real Lab Talavera de la Reina consists of three modular VFCW, each with a particular configuration. The first configuration consists of an unsaturated-saturated VFCW. This consists of two superimposed layers, a water-unsaturated top layer built with sand, and a water-saturated bottom layer built with gravel. The second configuration consists of an unsaturated-saturated VFCW integrated with forced bed aeration. This pilot followed a similar design of the previous configuration, but aerobic conditions in the water-unsaturated layer were further improved by injecting air using a blower. The third configuration consists of an unsaturated-saturated VFCW integrated with forced bed aeration and bioelectroconductive materials. Essentially, this pilot follows a similar scheme of the previous two configurations (two superimposed layers and an air-blow design) but the water-unsaturated layer is built with coke, a bioelectroconductive material that enhances nitrogen removal. These pilots are fed with raw municipal wastewater coming from Talavera de la Reina and recirculation was applied to enhance nitrification.

It is estimated that more than 360 m³ of municipal wastewater per year are to be treated with this technology. Expected removal rates of suspended solids and pollutants, including nitrogen, phosphorus, pathogens, and contaminants of emerging concern, are between 70% and 90%.

Main technological innovation:

• Bio-augmentation with Pseudomonas veroniland Pseudomonas autralisto attain higher removal of total coliforms and fecal coliforms.
• Use of bioelectroconductive materials to enhance removal of ammonium and contaminants of emerging concern.
• Integration of recirculation and forced aerated systems to improve nitrogen removal and sludge management, respectively.
• Demonstration of municipal wastewater treatment under real conditions.

Synergies:

• CETIM supported the design of the amended soil.
• INRAE and Aarhus University assisted with vertical flow constructed wetland design and bioelectroconductive material selection, respectively.