Thermal-Alkaline Pretreatment on the Decomposition of the Streptomycin Bacterial Residue

Abstract

ABSTRACTThere is still insufficient practical experience in the removing and degrading of streptomycin bacterial residues. The effect of thermal-alkaline pre-treatment on the decomposition of a streptomycin bacterial residue was investigated. Without NaOH pretreatment, the effect of thermal pre-treatment was not obvious. Soluble chemical oxygen demand and volatile suspended solids were 66.39% and 55.0% at 0.10 NaOH/TS ratio (g/g) and 368.15 K, respectively. The methane yield was 380 mL CH4/gVSadded at 303.15 K and no added NaOH and increased to 434 mL CH4/gVSadded at 0.10 NaOH/TS ratio (g/g) and 368.15 K. Thermal-alkaline pretreatment could significantly enhance not only the SCOD and VSS solubilization, but also the biodegradability. Methane production was enhanced, probably as a result of the breakdown of cell walls and membranes of microorganisms by thermal-alkaline pretreatment, which may facilitate the contact between organic molecules and anaerobic microorganisms.