Sludge treatment of a wastewater treatment plant

  • Alt

Year 2015 – 2016 

Project location San Fernando (Trinidad y Tobago).

Objectives Sludge thickening of the wastewater treatment plant San Fernando.

Installed technologies Two units SIGMA DAF FPAC200. 

Capacity Average flowrate of 30.2 m3/h per DAF.


The Ministry of Public Services of Trinidad and Tobago, through the institution of Aqueducts and Sewerage Water and Sewerage Authority (WASA), awarded the consortium formed by ACCIONA and the Atlatec group the project of the ‘San Fernando Complex’. ACCIONA hires Agua SIGMA to provide the treatment of the sludge generated at the plant.

The plant has a treatment capacity of 45,000 m3 / day per day and serves a population of 111,600 inhabitants. The facility has 16.3 kilometres of collectors, of which 12.5 are made through microtunnels with 11,964 service connections and 7 pumping stations with flow rates between 7 L / second up to 203 L / second.

For the treatment of the sludge generated in the plant, Agua SIGMA provides the design, construction and commissioning of a DAF FPAC dissolved air flotation physicochemical treatment system.

After purifying the wastewater, the plant generates a sludge load of more than 8000 kilograms per day with an average concentration of 0.6% (6000 mg / L) that requires to undergo a thickening process for subsequent treatment and stabilization. For this, Agua SIGMA designs, builds and installs two DAF FPAC dissolved air flotation equipment, achieving a sludge concentration of the San Fernando plant of up to 6% (60,000 mg / L).

             Sludge characteristics 


20 ºC 

8850 kg/day 


Solids removalSludge concentration

> 95% 


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