Anaerobic digestion of alkaline bleaching wastewater from a kraft pulp and paper mill using UASB technique.
Environ Technol
; 36(9-12): 1489-98, 2015.
Article
em En
| MEDLINE
| ID: mdl-25441833
ABSTRACT
Anaerobic digestion of alkaline kraft elemental chlorine-free bleaching wastewater in two mesophilic, lab-scale upflow anaerobic sludge bed reactors resulted in significantly higher biogas production (250±50 vs. 120±30 NmL g [Formula see text]) and reduction of filtered total organic carbon (fTOC) (60±5 vs. 43±6%) for wastewater from processing of hardwood (HW) compared with softwood (SW). In all cases, the gas production was likely underestimated due to poor gas separation in the reactors. Despite changes in wastewater characteristics, a stable anaerobic process was maintained with hydraulic retention times (HRTs) between 7 and 14â
h. Lowering the HRT (from 13.5 to 8.5â
h) did not significantly affect the process, and the stable performance at 8.5â
h leaves room for further decreases in HRT. The results show that this type of wastewater is suitable for a full-scale implementation, but the difference in methane potential between SW and HW is important to consider both regarding process dimensioning and biogas yield optimization.
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Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Papel
/
Reatores Biológicos
/
Biocombustíveis
/
Águas Residuárias
Tipo de estudo:
Evaluation_studies
Idioma:
En
Ano de publicação:
2015
Tipo de documento:
Article