Wetlands construídos. Sistema Francês. Remoção de fósforo. Escória de aciaria. Climas tropicais.
Name: GUILHERME BASTOS DE OLIVEIRA
Publication date: 12/10/2024
Examining board:
Name |
Role |
|---|---|
| CRISTIANE PEREIRA ZDRADEK | Examinador Externo |
| DANIEL RIGO | Examinador Interno |
| EDUMAR RAMOS CABRAL COELHO | Presidente |
| RICARDO FRANCI GONCALVES | Coorientador |
| ROSANE HEIN DE CAMPOS | Coorientador |
Summary: In Brazil's pursuit of universalizing sewage collection and treatment services,
decentralized sewage treatment systems emerge as a promising solution, particularly
for areas with low population density or precarious infrastructure. While Constructed
Wetland (CW) systems are a reality in other countries, Brazil still lacks a significant
number in operation. This study aimed to analyze the performance of a pilot-scale
French Vertical Constructed Wetland (PS-FVCW) using gravel and steel mill slag as
filter media, focusing on phosphorus removal from domestic wastewater and
compliance with current Brazilian legislation. The research was conducted at the
Parque Experimental de Saneamento Ambiental, Araçás Treatment Station, Vila
Velha-ES, Brazil, in a tropical zone. The module had dimensions of 1.80m (L) x 1.80m
(W) x 1.20m (H) and a nominal capacity of 1,296 L/day, operated at a flow rate of 0.54
L.s-1.pulse-1 and was monitored for 274 days (nine months). The results revealed
reductions in COD (63.29%), BOD520 (64.76%), TKN (60.26%), and suspended solids
(55.79%), with minimal pH variation (0.34). However, there was an 18.45% increase in
total solids (TS) in the effluent due to the precipitation of chemical compounds. Despite
the average phosphorus (P) concentration (3.26mg/L) not meeting the legal
requirements (0.02mg/L to 0.186mg/L), the removal efficiency (41.16%) is significant,
considering the system was monitored during the commissioning phase. The study did
not identify changes in the growth of the macrophytes, Typha domingensis, highlighting
the potential of steel mill slag in wetlands, especially in the French model. The findings
demonstrate the technical and ecological feasibility of the arrangement for raw sewage
treatment, presenting itself as a sustainable alternative for the use of steel industry
byproducts and the universalization of collection and treatment services.
