Journal of Water, Sanitation and Hygiene for Development (May 2022)

Raw sewage treatment by a single-stage vertical flow constructed wetland: a case study in Brazil

  • Mariko. A. Carneiro,
  • Gilson B. Athayde Junior,
  • Rennio F. Sena,
  • Camila A. Porto,
  • Vera Kohlgrüber

DOI
https://doi.org/10.2166/washdev.2022.038
Journal volume & issue
Vol. 12, no. 5
pp. 443 – 453

Abstract

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This paper evaluates the performance of raw domestic sewage treatment by a single-stage vertical-flow constructed wetland (VFCW) installed in Northeastern Brazil, where sanitation coverage is low. Biological and physicochemical parameters were monitored for 1 year to evaluate the system's performance. The impact of factors such as operational cycle and filter media on VFCW pollutant removal efficiencies was investigated. The means of removal efficiencies of chemical oxygen demand (COD), biological oxygen demand (BOD), and ammonia were 74.2, 87.9, and 82.1%, respectively. A statistically significant influence (p < 0.05) of substrate material on COD and ammonia removal efficiency was found. Ceramic construction waste media achieved the best performances compared with the traditionally used material and concrete construction waste. Operational cycles of 3.5/7 and 7/14 days of the feeding/resting period did not present a statistically significant influence (p < 0.05) on pollutant removal efficiencies. The single-stage VFCW pilot plant achieved a better global treatment performance than other VFCW reported in the literature; however, it showed a limitation in removing TS. The reduced installation costs, in addition to operation and maintenance simplicity, indicate a potential for single-stage VFCW applicability in the sewage treatment of housing units and small communities in Brazil and possibly in other developing countries in tropical areas. HIGHLIGHTS The single-stage vertical-flow constructed wetland (VFCW) overall means of removal efficiencies of COD, BOD, and ammonia were 74.2, 87.9, and 82.1%, respectively.; Filter media variation statistically influenced the removal efficiencies of COD and ammonia.; The operational cycles did not statistically influence the removal of pollutants.; The single-stage constructed wetland has a potential for application in housing units and small communities in tropical areas.;

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