Effect of nickel(II) on the biomass yield of the activated sludge

Gokcay, CF
Yetiş, Ülkü
Biomass yield of microorganisms is important in applied microbiology since it is the ultimate factor determining the amount of product produced regardless of whether product is growth-linked or not. In the case of environmental microbiology the opposite is true and minimizing the biomass produced, or the sludge in the relevant jargon, often is the prime goal. In this paper, a unique means of manipulating the microbial biomass yield of a heterogeneous culture to fulfil either of the two goals is presented. 5.0 mgl(-1) Ni(II) in the feed composition to a completely mixed, once- through, activated sludge was found to induce the observed biomass yield of the microbial culture developed from sewage. As compared with the base-line study without Ni(LI), where the reactor received synthetic wastewater only, true biomass yield was found to have increased along with the increased decay constant with the net effect of lowering observed biomass yield drastically at lower dilution rates and increasing it over that observed in the base-line study at higher dilution rates. At 10.0 mgl(-1) influent Ni(II) concentration the culture conditions almost reverted back to the base- line study and at 25 mgl(-1) Ni(II) concentration a truly steady-state condition could not be attained. Copyright (C) 1996 IAWQ.


Effect of chromium(VI) on the biomass yield of activated sludge
Yetiş, Ülkü; Gokcay, CF (1999-07-15)
Effect of 1-25 mg/l of influent Cr(VI) concentrations on true biomass yield (Y-t) and decay coefficient (k(d)) of activated sludge units was investigated in this study. To this purpose, completely mixed, once-through laboratory scale activated sludge units with acclimated cultures were operated. After obtaining dilute-out curves for each Cr(VI) concentration, the values of Y-t and k(d) were determined. The results revealed that presence of Cr(VI) caused stimulatory effects on biomass yield and maintenance u...
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Sanin, Faika Dilek (2001-02-01)
Bacterial extracellular polymers have been found to be important in bioflocculation of activated sludge. In this study ethylene diamine tetra acetic acid (EDTA) method of extracting bacterial extracellular polymers is examined. Following extractions, it is observed that EDTA extracted significant amounts of biopolymers. However, the chemical treatment causes serious changes in sludge properties. Sludge particle size is reduced from 21 mum to 14.6 mum, filtration properties of sludge deteriorates, indicated ...
Effect of Synthesis Conditions on the Structure and Catalytic Performance of V- and Ce-Incorporated SBA-15-like Materials in Propane Selective Oxidation
Aktas, Ozge; YAŞYERLİ, SENA; DOĞU, GÜLŞEN; Doğu, Timur (2010-08-04)
Vanadia- and/or ceria-incorporated SBA-15-like materials were prepared by impregnation and one-pot hydrothermal synthesis procedures at different solution pH values. The pH of the synthesis solution was found to have a very strong effect on the pore structure, chemical composition, and morphology of the synthesized materials. Materials synthesized by impregnation of V and/or Ce and by the one-pot hydrothermal route at pH << 1.0 showed the characteristic ordered pore structure of SBA-15. However, the materia...
Effects of Ni(II) on respirometric oxygen uptake
Albek, M; Yetiş, Ülkü; Gokcay, CF (1997-11-01)
The effects of Ni(II), substrate and initial biomass concentrations on biochemical oxygen demand (BOD) were studied by using an electrolytic respirometer. The effects of Ni(II) (2.5, 5.0, 10.0, 25.0 mg/l) and substrate (325, 650, 1300 mg/l as chemical oxygen demand) in a synthetic wastewater with differing initial biomass concentrations (1, 10, 100 mg/l) were investigated. The biomass-to-metal ratio was found to be the most important parameter affecting the measured BOD values. The maximum specific growth r...
Effect of Alkyl Derivatization on Several Properties of N-Halamine Antimicrobial Siloxane Coatings
Kocer, Hasan B.; Akdağ, Akın; Ren, Xuehong; Broughton, R. M.; Worley, S. D.; Huang, T. S. (American Chemical Society (ACS), 2008-10-01)
Variation of alkyl substitution at position 5 on the hydantoin ring of a series of N-halamine siloxane derivatives has been employed to better understand the biocidal activities of these compounds for use in preparing antimicrobial coatings. The alkyl derivatization of the hydantoin ring at its 5 position, while an essentially constant chlorine loading is maintained at the I position, has shown that there is little dependence of the antimicrobial efficacy against Escherichia coli O157:H7 on the alkyl chain ...
Citation Formats
C. Gokcay and Ü. Yetiş, “Effect of nickel(II) on the biomass yield of the activated sludge,” WATER SCIENCE AND TECHNOLOGY, pp. 163–171, 1996, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/36018.