Brazilian Journal of Enviromnent
Open Access Journal
CiteScore
0.5
Indexada na
SCOPUS
QUALIS
B3
2017-2021
quadriênio
Open Access Journal
0.5
Indexada na
SCOPUS
B3
2017-2021
quadriênio
Tecnologias e Estudos Ambientais | Vol. 13 Issue 3 (2025)
Published in October 18, 2025
The present study aimed to evaluate the biodegradability and treatability of household gray water, in addition to analyzing the efficiency of a modified biofilter with recycled glass filter media, replacing traditional wood shavings. The research was divided into two stages. In the first, gray water samples were collected in three municipalities and analyzed for the ratio between Chemical Oxygen Demand (COD) and Biochemical Oxygen Demand (BOD₅), to determine biodegradability. The results revealed that 33% of the samples presented high biodegradability, 46.67% intermediate and 20% low, indicating that the choice of the type of treatment should consider the specific characteristics of each sample. In the second stage, the efficiency of a modified biofilter was evaluated in comparison to the conventional model, through thirteen filtration runs and five collection campaigns, respectively. The physical-chemical analyses demonstrated that the biofilter with recycled glass presented COD removal ranging from 5% to 72%, in addition to not increasing sodium levels in the treated gray water — a behavior opposite to that observed in the conventional biofilter. The results indicate that crushed glass is a promising filter medium, with potential to improve the quality of treated gray water.
This work is licensed under a Creative Commons Attribution 4.0 International License.
Copyright (c) 2025 Sheila Ferreira Santos, Talys Brendo Sá da Silva, Guilherme Henrique de Lima Freitas de Lima Freitas, Cristiane Xavier Galhardo, Miriam Cleide Cavalcante de Amorim
https://orcid.org/0009-0008-6334-7446