CWetlandsData
CWetlandsData
CWetlandsData

UNACEM cement company

10/03/2021  Photo: UNACEM

Since 2005, UNACEM began pilot tests to implement a Wastewater Treatment Plant (WWTP) using constructed wetlands. The WWTP started it built in 2009 and finished in 2010 (Fig. 1 and 2).
Currently, it operates a total flow of 600 m3 per day (6.94 L/s). The objective of the project is to collect and treat 100% of the company's domestic and industrial effluents, and reach a quality for reuse in irrigation; achieving the discharge in the sewer network.

The treatment system is integrated by:

  • Wastewater collection system or Sewer catchment
  • Pretreatment (Grates chamber, gauge Parshall, regulation tank).
  • Primary treatment (Flocculation tank, laminar settler, aeration tank).
  • Secondary treatment (Horizontal subsurface flow constructed wetlands).
  • Complementary treatment (Bypass box, partition chamber, mixing and flocculation tanks, filter press for sludge dehydration, disinfection with chlorine, self-cleaning filters, storage and distribution of treated waste water).
CWetlandsData

Figure 1. Laying of the geomembrane (Photo: Rosa Miglio)

The plant species used in the constructed wetlands, allowed to integrate the Wastewater Treatment Plant of with the local landscape (Fig. 3).

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Figure 2. Plant cultivation in the constructed wetland (Photo: Rosa Miglio)

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Figure 3. Constructed Wetland, UNACEM cement company, Lima, Perú (Photo: UNACEM)

Two species were selected: Achira (Canna indica) and Paragüitas (Cyperus alternifolius) (Fig. 4 & 5), both has a fast growing and moderate development.

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Figure 4. Wetland Cells cultivated with Achira (Canna edulis), (Photo: Rosa Miglio)

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Figure 5. Paragüitas (Cyperus alternifolius), (Photo: Rosa Miglio)

Currently, the effluent is used to irrigate parks and gardens and the fire system. Treatment efficiency is greater than 95%, reaching an average BOD below 10 mg/L. The energy required by the WWTP comes from the National Interconnected Electric System (SEIN), through a contract with the company “El Platanal”, which operates hydroelectric plants. The annual operating cost is 120 thousand dollars and the savings in water consumption exceed 110 thousand m3.

General Information

Location: UNACEM cement company

City:Villa María del Triunfo

State: Lima

Country: Peru

Project Size:25000 m2

Wetland Type (System/Cells): 
Horizontal subsurface flow / 6 cells of 30 m x 30 m each one and a depth of 0.6 m.

Company/Organization:UNACEM S.A.A.