Aerobic and Anaerobic Biotransformations and Treatment of Chlorinated Pulp Bleach Waste Constituents

Biotransformations and treatment of several chlorinated, hydroxylated and methoxylated monoaromatic compounds were studied in batch bottle bioassays and continuous-flow fluidized-bed reactors. With the aerobic enrichment, polychlorinated phenols were biodegraded with simultaneous release of inorganic chloride in amounts equal to mineralization stoichiometrics. Aerobic removal of 4,5-dichlorocatechol and 4,5- dichlorovanillin were associated with the release of inorganic chlorine. The aerobic enrichment showed no activity against mono- or di-O-methylated phenols. With the anaerobic enrichment, reductive transformations of these compounds were observed. These transformations included reductive dechlorinations, de-O-methylations and dehydroxylations. High-rate operation of an aerobic fluidized-bed reactor resulted in over 99.7% biodégradation of polychlorophenols. In the anaerobic fluidized-bed reactor, over 95% removal of chlorophenols with no apparent accumulation of lower chlorinated phenols indicated complete dechlorination.

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High-rate microbial selenate reduction in an up-flow anaerobic fluidized bed reactor (FBR)

The Science of The Total Environment ◽

10.1016/j.scitotenv.2020.142359 ◽

2020 ◽

Vol 749 ◽

pp. 142359

Author(s):

Su Yan ◽

Ka Yu Cheng ◽

Maneesha P. Ginige ◽

Guanyu Zheng ◽

Lixiang Zhou ◽

...

Keyword(s):

Fluidized Bed ◽

Fluidized Bed Reactor ◽

High Rate ◽

Anaerobic Fluidized Bed Reactor

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Removal of microcystin-LR from drinking water with TiO2-coated activated carbon

Water Science & Technology Water Supply ◽

10.2166/ws.2004.0088 ◽

2004 ◽

Vol 4 (5-6) ◽

pp. 21-28

Author(s):

S.-C. Kim ◽

D.-K. Lee

Keyword(s):

Drinking Water ◽

Activated Carbon ◽

Synergistic Effect ◽

Fluidized Bed ◽

Continuous Flow ◽

High Surface ◽

High Surface Area ◽

Fluidized Bed Reactor ◽

Exterior Surface ◽

Tio2 Particles

TiO2-coated granular activated carbon was employed for the removal of toxic microcystin-LR from water. High surface area of the activated carbon provided sites for the adsorption of microcystin-LR, and the adsorbed microcystin-LR migrated continuously onto the surface of TiO2 particles which located mainly at the exterior surface in the vicinity of the entrances of the macropores of the activated carbon. The migrated microcystin-LR was finally degraded into nontoxic products and CO2 very quickly. These combined roles of the activated carbon and TiO2 showed a synergistic effect on the efficient degradation of toxic microcystin-LR. A continuous flow fluidized bed reactor with the TiO2-coated activated carbon could successfully be employed for the efficient photocatalytic of microcystin-LR.

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Influence of Seeding Conditions on Initial Biofilm Development during the Startup of Anaerobic Fluidized Bed Reactors

Water Science & Technology ◽

10.2166/wst.1989.0219 ◽

1989 ◽

Vol 21 (4-5) ◽

pp. 157-165 ◽

Cited By ~ 2

Author(s):

F. Ehlinger ◽

J. M. Audic ◽

G. M. Faup

Keyword(s):

Fluidized Bed ◽

Future Development ◽

Protein Concentration ◽

Specific Activity ◽

Fluidized Bed Reactor ◽

Fluidized Bed Reactors ◽

Support Material ◽

Biofilm Development ◽

Initial Biofilm

The characterization of the biofilm of an anaerobic fluidized-bed reactor was completed under standard conditions. The distribution of the fixed protein concentration depended on the level in the reactor. The protein concentration reached 1520 µg.g−1 of support at the top of the reactor and only 1200 µg.g−1 at the bottom after 504 hours of operation but the specific activity of the biofilm was 33×10−4 µM acetate.h−1.mg−1 proteins at the bottom and only 26×10−4 µM.h−1.mg−1 at the top. The efficiency of a fluidized bed reactor and the composition of the biofilm changed with an increase of the pH from 7 to 8.5 during the seeding of the support material. Future development of the biofilm and the specific activity of the support were affected.

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