Distinct effects of chemical- and bio- flocculants on the sludge acidogenic fermentation for volatile fatty acids production by affecting the acidogenic steps, microbial community structure and metabolic functions.
Sci Total Environ
; 905: 167207, 2023 Dec 20.
Article
em En
| MEDLINE
| ID: mdl-37730033
ABSTRACT
Flocculants play crucial roles in sludge treatment, while the specific impact of chemical and bio-flocculants on sludge anaerobic fermentation was unknown. This study unveiled the contrasting effects of chitosan (CTS) and polyaluminum chloride (PAC) on volatile fatty acids (VFAs) generation during sludge fermentation. CTS supplementation resulted in 17.2 % increase in VFAs production, while PAC exposure led to 7.6 % reduction compared to the control. Further investigation revealed that CTS facilitated sludge solubilization and hydrolysis, thus providing sufficient organic substrates for VFAs generation. Additionally, environmental-friendly CTS exposure positively influenced the abundance and activity of functional anaerobes, as well as the expression of genes associated with VFAs biosynthesis. In contrast, PAC exposure resulted in the formation of larger sludge flocs, which hindered WAS solubilization and hydrolysis. Meanwhile, its potential microbial toxicity also impeded the microbial metabolic activity (i.e., genetic expressions), resulting in unsatisfactory VFAs production.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Esgotos
/
Microbiota
Idioma:
En
Revista:
Sci Total Environ
Ano de publicação:
2023
Tipo de documento:
Article
País de afiliação:
China