Influence of ozone pre-treatment on sludge anaerobic digestion: removal of pharmaceutical and personal care products.
The effect of an oxidative pre-treatment with ozone on the removal of Pharmaceutical and Personal Care Products (PPCPs) during the anaerobic digestion of sewage sludge has been investigated. Besides, the digested sludge characteristics in terms of pathogens content, dewatering properties, heavy metals content and linear alkylbenzene sulfonates (LAS) were determined. During ozonation (20mg O(3)/g TSS), about 8% of volatile solids (VS) and 60% of the chemical oxygen demand (COD) were solubilized. However, no mineralization was observed. The elimination of VS and total COD during anaerobic digestion were not affected by ozone treatment with efficiencies ranging from 60% to 65%. All PPCPs considered were removed during anaerobic treatment of sludge, with efficiencies ranging from 20% to 99%. No significant influence of ozone pre-treatment was observed on PPCPs elimination except for carbamazepine. Pathogens, heavy metals and LAS contents after conventional and pre-ozonation treatment of sewage sludge were below the legal requirements. However, the dewatering properties of sludge were deteriorated when the ozone pre-treatment was applied.
Carballa
Marta
M
Department of Chemical Engineering, School of Engineering, University of Santiago de Compostela, Rua Lope Gómez de Marzoa, s/n. E-15782 Santiago de Compostela, Spain. mcarbala@usc.es
Manterola
Garbiñe
G
Larrea
Luis
L
Ternes
Thomas
T
Omil
Francisco
F
Lema
Juan M
JM
D000476:Alkanesulfonates / Q000032:analysis; D000693:Anaerobiosis; D006795:Household Products / Q000032:analysis*; D019216:Metals, Heavy / Q000032:analysis; D010100:Oxygen / Q000032:analysis; D010126:Ozone / Q000737:chemistry*; D004364:Pharmaceutical Preparations / Q000032:analysis*; D010865:Pilot Projects; D012722:Sewage / Q000032:analysis*; D014871:Water Microbiology
D000476:Alkanesulfonates; D019216:Metals, Heavy; D004364:Pharmaceutical Preparations; D012722:Sewage; D010126:Ozone; D010100:Oxygen