title: Effects of microwave and alkali induced pretreatment on sludge solubilization and subsequent aerobic digestion.
abstract: Individual and combined effects of microwave (MW) and alkali pretreatments on sludge disintegration and subsequent aerobic digestion of waste activated sludge (WAS) were studied. Pretreatments with MW (600W-85°C-2 min), conventional heating (520 W-80°C-12 min) and alkali (1.5 g NaOH/L - pH 12-30 min) achieved 8.5%, 7% and 18% COD solubilization, respectively. However, combined MW-alkali pretreatment synergistically enhanced sludge solubilization and achieved 46% COD solubilization, 20% greater than the additive value of MW alone and alkali alone (8.5+18%=26.5%). Moreover, the results of the batch aerobic digestion study on MW-alkali pretreated sludge showed 93% and 63% reductions in SCOD and VSS concentrations, respectively, at 16 days of SRT. The VSS reduction was 20% higher than that of WAS without pretreatment.
authors.affiliation: Graduate Institute of Environmental Engineering, National Taiwan University, Taipei 106, Taiwan, ROC.
authors.forename: Chia-Jung
authors.initials: CJ
authors.lastname: Chang
authors.forename: Vinay Kumar
authors.initials: VK
authors.lastname: Tyagi
authors.forename: Shang-Lien
authors.initials: SL
authors.lastname: Lo
mesh_terms: D000332:Aerobiosis; D000468:Alkalies / Q000737:chemistry*; D008872:Microwaves; D012722:Sewage; D012995:Solubility; D013696:Temperature
chemical_list: D000468:Alkalies; D012722:Sewage