Evaluation of the aerobic biodegradability of process water produced by hydrothermal carbonization and inhibition effects on the heterotrophic biomass of an activated sludge system

As a part of activated sludge system, oxidation ditch has a special form like a canal without end point. Rotor is used to diffuse oxygen from air to the water.

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Parameters for Measuring the Activity and Viability of Activated Sludge

Water Quality Research Journal ◽

10.2166/wqrj.1974.022 ◽

1974 ◽

Vol 9 (1) ◽

pp. 235-249 ◽

Cited By ~ 1

Author(s):

S.G. Nutt ◽

K.L. Murphy

Keyword(s):

Organic Carbon ◽

Activated Sludge ◽

Biological System ◽

Analytical Methods ◽

Heterogeneous System ◽

Removal Rate ◽

Bacterial Species ◽

Atp Content ◽

Culture Studies ◽

Activated Sludge System

Abstract Conventional wastewater parameters are accepted as inadequate estimates of the condition of activated sludge but numerous other indices have been suggested as specific measurements of the activity and viability of the biomass. Literature in the related fields of microbiology and biochemistry were reviewed in order to select the most appropriate activity parameters for application to a heterogeneous biological material. Modified analytical methods were applied to a well-controlled biological system containing a single predominant bacterial species to evaluate the relative merit of each as an indicator of viability and activity. The potential of each parameter in a complex heterogeneous system was determined by monitoring each index in a bench activated sludge system. The predominant culture studies indicated that the ATP content of the biomass and the dehydrogenase activity were potential indicators of cell viability in a simple system. However, in the complex activated sludge system, only the ATP content showed significant correlation to the organic carbon removal rate.

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Solids Concentrations in a Treatment Plant Effluent

Water Science & Technology ◽

10.2166/wst.1992.0783 ◽

1992 ◽

Vol 26 (9-11) ◽

pp. 2543-2546

Author(s):

M. Defrain ◽

F. Schmidt

Keyword(s):

Waste Water ◽

Activated Sludge ◽

Federal Republic ◽

Treatment Plant ◽

Analysis Procedure ◽

Process Water ◽

Federal Republic Of Germany ◽

Output Variable ◽

Sludge Treatment ◽

Sewerage Network

In the calculations customarily used to dimension nitrification and denitrification plants in the Federal Republic of Germany, solids in the influent of the biological stage represent a significant output variable. Numerous modified methods based on nationally and internationally standardized analysis procedures are available to determine solids concentrations in waste-water. Tests showed that different values are measured depending on the method of analysis employed. Harmonization of the analysis procedure is advisable to ensure comparable conditions for the calculation of activated sludge tank volumes. The solids reaching a treatment plant originate from two main sources. Filterable materials are passed to the treatment plant via the preceding sewerage network with its industrial and commercial users, but are also carried by process water from sludge treatment. The influence of process water on wastewater composition is illustrated by reference to the Wuppertal-Buchenhofen treatment plant.

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TREATABILITY OF 2,4-D PRODUCTION WASTEWATERS

Water Science & Technology ◽

10.2166/wst.1994.0067 ◽

1994 ◽

Vol 30 (3) ◽

pp. 73-78 ◽

Cited By ~ 3

Author(s):

O. Tünay ◽

S. Erden ◽

D. Orhon ◽

I. Kabdasli

Keyword(s):

Hydrogen Peroxide ◽

Activated Sludge ◽

Partial Oxidation ◽

Chloride Concentration ◽

Chemical Oxidation ◽

Cod Removal ◽

Optimum Conditions ◽

Organic Loading ◽

Activated Sludge System ◽

Biological Treatability

This study evaluates the characterization and treatability of 2,4-D production wastewaters. Wastewaters contain 20000-40000 mg/l COD, 17000-30000 mg/l chloride and pH is around 1.0. Chemical oxidation with hydrogen peroxide provided almost complete COD removal. The optimum conditions are 3:1 H2O2/COD oxidant dosage, 3000 mg/l Fe3+ as catalyst and pH 3. Partial oxidation at 0.5:1 H2O2//COD ratio is also effective providing 67% COD removal. A batch activated sludge system is used for biological treatability. Dilution is needed to maintain a tolerable chloride concentration which increases through COD removal. pH also increased during COD removal. 85% COD removal is obtained for the 50% dilution at an organic loading of 0.3 day‒1 on a COD basis. Completely and partially oxidized wastewaters are also treated in the activated sludge down to 30 mg/l BOD5.

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