PVA-gel beads enhance granule formation in a UASB reactor.
PVA-gel beads were used as a biocarrier in a lab-scale UASB reactor treating synthetic wastewater composed of corn steep liquor (CSL) with the aim of evaluating its use as a growth nucleus to enhance granule formation. Over 117 days of operation, the organic loading rate was increased to 22.5kgCOD/m3/day with an influent COD of about 10.8g/L at an HRT of 12h with COD removal efficiencies greater than 87%. By the end of the study period, the PVA-gel turned black and granule formation was achieved as compared with the formation of much fewer natural granules without the PVA-gel nucleus. No filamentous bacteria were found on the surface or interior of the PVA-gel beads. The PVA-gel granules had an average settling velocity 200m/h (5cm/s), and a biomass attachment of 0.93g VSS/g PVA-gel. The required time for formation of PVA-gel granules was thus demonstrated to be shorter than that of ordinary sludge granules under the experimental conditions used in this study.
Wenjie
Zhang
Z
Graduate School of Science and Technology, Kumamoto University, 2-39-1, Kurokami, Kumamoto 860-8555, Japan. zhangwj_zhangwj@hotmail.com
Dunqiu
Wang
W
Yasunori
Koga
K
Taichi
Yamamoto
Y
Li
Zhang
Z
Kenji
Furukawa
F
D001419:Bacteria / Q000378:metabolism*; D019149:Bioreactors; D005227:Fatty Acids / Q000032:analysis; D005740:Gases / Q000378:metabolism; D005782:Gels; D008863:Microspheres; D011142:Polyvinyl Alcohol / Q000737:chemistry*; D012722:Sewage; D014835:Volatilization
D005227:Fatty Acids; D005740:Gases; D005782:Gels; D012722:Sewage; D011142:Polyvinyl Alcohol