Effects of hydraulic residence time on metal uptake by activated sludge

Ozbelge, TA
Özbelge, Hilmi Önder
Tursun, M
The combined uptake Of Cu2+ and Zn2+ by activated sludge (biomass) was investigated at steady state in an activated sludge process (ASP) without recycle (namely, once-thro ASP), for different values of influent metal concentrations and hydraulic residence time in the range of 2.5-40 h. The experiments were performed at a constant pH of 7 and temperature of 25 degreesC. The results showed that the percentage removal of both copper and zinc by activated sludge increased with the increasing residence time; moreover, the percent metal uptakes were higher for both metals at the low level of influent metal concentrations [rho(Cu2+) = 1.5 mg/L and rho(Zn2+) = 9 mg/L], than those at the higher level of concentrations [rho(Cu2+) = 4.5 mg/L and rho(Zn2+) = 27 mg/L]. The least represented forms of both Cu2+ and Zn2+ in activated sludge were their sulfides, and the dominant metal forms were found to be 'organically bound' for both of the metals, Zn2+ and Cu2+.


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Soydas, Belma; Kalıpçılar, Halil; Culfaz, Ali (American Chemical Society (ACS), 2010-06-02)
Thin zeolite membranes of MFI type were prepared on alpha-Al2O3 supports by midsynthesis addition of silica in a recirculating flow system at 95 degrees C The synthesis was started with the batch composition of 80SiO(2): 30TPAOH:1500H(2)O which was changed to 80SiO(2)center dot 9TPAOH:1500H(2)O by addition of silica Mkt 24, 48, or 72 h Compared to synthesis at constant composition. it is possible to affect the rates of nucleation and crystal growth to obtain membranes with better quality by changing the ove...
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Guvenc, A; Mehmetoglu, U; Mehmetoglu, T (Informa UK Limited, 2004-01-01)
Supercritical fluid extraction (SFE) using CO2 was performed on soil material artificially contaminated with diesel fuel. Raising the temperature from 313 K to 343 K caused the recovery efficiency to increase from 52 to 76%. Pressure and CO2 flow rate were found to be less important. As expected, increasing extraction time resulted in higher recoveries. Ultrasonic pretreatment of the soil material was found to be very effective, possibly due to disrupting the strong interaction bonding between soil matrix a...
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Boz, N; Doğu, Timur; Murtezaoglu, K; Dogu, G (Elsevier BV, 2004-08-10)
Activities of ion-exchange resin catalysts, having different hydrogen exchange capacities ranging between 5.1 and 1.3 meq H+/g, on the etherification reactions of 2M1B (2-methyl-1-butene) and 2M2B (2-methyl-2-butene) with ethanol were experimentally tested in a fixed bed reactor. These catalysts were prepared by the heat treatment of Amberlyst-15 catalysts at 220 degreesC at different durations of time and also by the synthesis of sulfonated styrene divinyl benzene cross-linked resins. Activity of these cat...
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Ozbelge, TA; Ozbelge, OH; Baskaya, SZ (Elsevier BV, 2002-09-01)
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A series of trimeric monomers bearing thiophene donor units and fluorinated analogues of benzothiadiazole acceptor units was synthesized via donor-acceptor-donor approach and polymerized electrochemically in order to investigate the effect of fluorine atom on electro-optical properties of both monomers and their corresponding polymers. All monomers exhibited solvatochromic and fluorescent properties. The introduction of fluorine atom into the conjugated backbone increased the oxidation potentials. Upon movi...
Citation Formats
T. Ozbelge, H. Ö. Özbelge, and M. Tursun, “Effects of hydraulic residence time on metal uptake by activated sludge,” CHEMICAL ENGINEERING AND PROCESSING, pp. 23–32, 2005, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/51523.