Industrial water treatment
It is one of the largest purification plants in Europe, combining two large processes that operate in parallel: water line and sludge line.
- Project: Wastewater treatment plant, Baix Llobregat.
- Entity: Sociedad Depuradora del Baix Llobregat, S.A.
- Location: Prat de Llobregat, Barcelona (Catalonia). Spain.
- Capacity: Flow: 420,000 m3/day. Population: 2,275,000.
- Prefilter wells with screens with grids with 100 mm of separation between bars and 2 bivalve grabs with 500 litre capacity.
- Raw water pumping with 8+1 centrifugal pumps with the capacity to elevate up to 6,526 m3/h each and with trim.
- Discharge of thick and thin solids, in 8 channels equipped in 2 lines. Elimination of sand and oils using 12 desanders-deoilers.
- Measurement of the flow and by-pass to limit the flow entering the biological treatment to 35,000 m3/h.
- Twelve 20x60 m rectangular primary decanters.
- Biological treatment in 8 lines through activated sludge, combining anaerobic, anoxic and oxygenation processes.
- 14 circular secondary decanters with a diameter of 45.5 m.
- Sifting and thickening of sludge using 4 thickeners.
- Thickening of excess biological sludge using 4 centrifuges of 260 m3/h.
- Anaerobic sludge digestion using 8 digesters, each 7,180 m3.
- Four centrifuges, each 60 m3/h for the dehydration of digested sludge.
- Low storage of gas in 2 membrane tanks.
- Thermal drying of dehydrated sludge.
- Energy recovery from the digestion gas using 4 motor generators, each 2.8 MWe.
- Odour treatment for pre-treatment deodorising.