Helping WWTP managers to address the volatile methylsiloxanes issue-Behaviour and complete mass balance in a conventional plant

• Type: Article in International Scientific Journal
• Date: 2023

Authors

Francisco Sánchez-Soberón (Author) FEUP; Gabriel Pantuzza (Author) FEUP; Madalena Fernandes (Author) FEUP; Vera Homem (Author) FEUP; Arminda Alves (Author) FEUP; Milton Fontes (Author) Other; Magda André (Author) Other; Joana Cunha (Author) Other; Nuno Ratola (Author) FEUP

Journal

Title: Environmental Research

Vol. 234 No. 116564

ISSN: 0013-9351

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 0 Citations

Scopus - 0 Citations

Associated Projects

ALiCE - ALiCE - Laboratório Associado em Engenharia Química

LEPABE - Financiamento Plurianual 2020-2023 da Unidade de I&D LEPABE - Laboratório de Engenharia de Processos, Ambiente, Biotecnologia e Energia

LaNSiloT - LAunching New SILOxane Treatments: assessing effluent, sludge and air quality and improving biogas production in WWTPs

Healthy Waters - Healthy Waters - Identification, Elimination, Social Awareness and Education of Water Chemical and Biological Micropollutants with Health and Environmental Implications

Other information

Authenticus ID: P-00Y-YAB

DOI: 10.1016/j.envres.2023.116564

Abstract (EN): Volatile methylsiloxanes (VMSs) are a group of additives employed in different consumer products that can affect the quality of the biogas produced in wastewater treatment plants (WWTPs). The main objective of this study is to understand the fate of different VMSs along the treatment process of a WWTP located in Aveiro (Portugal). Thus, wastewater, sludge, biogas, and air were sampled in different units for two weeks. Subsequently, these samples were extracted and analyzed by different environment-friendly protocols to obtain their VMS (L3-L5, D3-D6) concentrations and profiles. Finally, considering the different matrix flows at every sampling moment, the mass distribution of VMSs within the plant was estimated. The levels of n-ary sumation VMSs were similar to those showed in the literature (0.1-50 & mu;g/L in entry wastewater and 1-100 & mu;g/g dw in primary sludge). However, the entry wastewater profile showed higher variability in D3 concentrations (from non detected to 49 & mu;g/L) than found in previous studies (0.10-1.00 & mu;g/L), likely caused by isolated releases of this compound that could be related to industrial sources. Outdoor air samples showed a prevalence of D5, while indoor air locations were characterized by a predominance of D3 and D4. Differences in sources and the presence of an indoor air filtration system may explain this divergence. Biogas was characterized by n-ary sumation VMSs concentrations (8.00 & PLUSMN; 0.22 mg/m3) above the limits recommended by some engine manufacturers and mainly composed of D5 (89%). Overall, 81% of the total incoming mass of VMSs is reduced along the WWTP, being the primary decanter and the secondary treatment responsible for the highest decrease (30.6% and 29.4% of the initial mass, respectively). This reduction, however, is congener dependant. The present study demonstrates the importance of extending sampling periods and matrices (i.e., sludge and air) to improve sample representativity, time-sensitivity, and the accuracy of mass balance exercises.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 11