Benalmádena

Location: Benalmádena Municipal Water Company main office.

Climate: The city experiences a typically Mediterranean climate, characterised by short, warm, humid, arid, and mostly clear summers, ranging from 28°C to 30°C, and long, cold, windy, and partly cloudy winters (around 17 ºC).

Context: Benalmadena is a city in the Costa del Sol region of Andalusia, Spain, with ~68,000 inhabitants, peaking up to 200,000 in the holiday season. Benalmadena has an interesting location to research residential greywater treatment and reclamation, given the number of residential buildings with greywater separation, integrating the treatment in very valuable urban

Typology: Green wall for greywater treatment and reuse for irrigation.

Description: Urban Real Lab Benalmadena consists of a 31 m² green wall held to the façade of the city Municipal Water company main office using an auxiliar structure. The system is expected to treat greywater collected from washbasins. Greywater is to be fed via drip irrigation during off-hours. Treatment occurs as water percolates to the bottom of plant pots, where elimination of solids and nutrients is expected. Treated water is then collected and reuse for irrigation of the green wall, mainly during water demanding months (summer). The green wall system can hold up to 1,000 m³ of grey water per year. 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:

• The system uses adsorbent materials, coco coir and coarser light material.
• Hydraulic and organic loading rate were established according to results of laboratory experiments to avoid clogging and a hydraulic short circuit.
• The pilot demonstrates the performance of such technologies under stress conditions (for a public building with low high-water demand as it is set in a public area).

Synergies:

• CETIM assisted in finding suitable absorbent material to avoid clogging issues.
• POLITO tested the coarser light material to decrease structural stress and further operational problems.