Aerobic treatments

Table 11.2 provides a summary of the main features of aerobic and anaerobic wastewater treatment. Aerobic treatment processes are generally restricted to BOD < 1000 mg/liter unless pure oxygen is used for aeration. 

Aerobic treatment is generally appHed to lower strength wastewaters, whereas anaerobic treatment is employed as a pretreatment for high strength wastewaters. The choice of process depends both on the concentration of organics and the volume of wastewater to be treated. 

Under optimum conditions of anaerobic and aerobic treatment in activated sludge plants, up to 90% removal of phosphorus can be achieved. Biological removal can, at best, achieve efffnent concentrations of about 0.2 mg total phosphorus but more usually reduces phosphorus to about ImgUh... 

Aerobic Treatment. The activated sludge process depends on aerobic biological action. In this case the microorganisms, in searching for food, break down the complex organic substances into simple stable substances. This process results in the removal of soluble and suspended organic matter from wastewater. 

Drzyzga O, D Bruns-Nagel, T Gorontzy, K-H Blotevogel, E von Low (1998) Incorporation of " C-labeled 2,4,6-trinitrotoluene metabolites into different soil fractions after anaerobic and anaerobic-aerobic treatment of soil/molasses mixtures. Environ Sci Technol 32 3529-3535. 

Case 1 Anaerobic/Aerobic Treatment of Municipal Landfill Leachate... 

Case 1 Anaerobic/Aerobic Treatment of Municipal Landfill Leachate in Sequential Two-Stage Up-Flow Anaerobic Sludge Blanket Reactor (UASB)/Aerobic Completely Stirred Tank Reactor (CSTR) Systems... 

Osman, N.A, and Sponza, D.T., Anaerobic/aerobic treatment of municipal landfill leachate in sequential two-stage up-flow anaerobic sludge blanket reactor (UASB)/completely stirred tank reactor (CSTR) system, Proc. Biochem., 40, 895-902, 2005. 

Bacteria can grow in two main environments, aerobic and anaerobic. In aerobic treatment, aerobic and facultative bacteria use molecular oxygen as their terminal electron acceptor. The treatment occurs in the presence of a molecular oxygen supply. In anaerobic treatment, anaerobic and... 

The advantage of ex situ biological treatment is the ability to control the effluent quality. The use of air for aerobic treatment is easier to control and costs less. Nutrient can be added more effectively and the temperature can be controlled. 

Different kinds of bioreactors and configurations have been used to treat wastewater containing formaldehyde and urea, and three different kinds of treatments can be applied anaerobic treatment, aerobic treatment, and combined nitrification and denitrification treatments. 

Canto and colleagues52 operated an integrated anoxic-aerobic treatment of wastewaters from a synthetic resin producing factory (Figure 19.9). These authors managed to treat up to 2.01 kg/m3 d COD and up to 0.93 kg/m3 d TKN with removal efficiencies of 80 to 95% and 58 to 93% for COD and TKN, respectively. 

Hamoda, M.F., Aerobic treatment of ammonium fertilizer effluent in a fixed-film biological system, Water Sci. Technol., 22, 75-84, 1990. 

Rittstieg, K., Robra, K.H., and Somitsch, W., Aerobic treatment of a concentrated urea wastewater with simultaneous stripping of ammonia, Appl. Microbiol. Biotechnol., 56, 820-825, 2001. 

Canto, M., Gomez, J., Kennes, C., and Veiga, M.C., Integrated anoxic-aerobic treatment of wastewaters from a synthetic resin producing factory, European Conference on New Advances in Biological Nitrogen and Phosphorus Removal for Municipal or Industrial Wastewaters, Narbonne, France, October 12-14,1998. 

Some kraft mills use basins without mechanical aerators. Known as stabilization basins, this is the simplest form of aerobic treatment. This process uses shallow basins that cover very large areas and relies on natural diffusion of air into the wastewater and algae to create aerobic conditions. At depths greater than 1.2 m (4 ft), anaerobic microorganisms will become active in lower depths thus, stabilization basins are shallow. Typically, the basin is earthen although some are lined with compacted clay. Wastewater retention time may last up to 30 d to achieve up to 90% BOD5 removal. 

Aerobic treatment systems can be used for the food industry wastewater treatment as well. However, if the organic strength is very high, the use of aerobic systems may not be effective. A combination of anaerobic/aerobic treatment may be necessary. 

Annachhatre, A.P. and Bhamidimarri, S.M.R., Aerobic treatment of meat industry wastewater COD removal and nitrification, process industries power the Pacific rim Sixth conference of the Asia Pacific confederation of chemical engineering Twenty first Australasian chemical engineering conference Official proceedings of combined conference 1993 137-142, 1993. 

Aerobic/extended aerobic treatment 4.9-10 7.4 2 Activated sludge Australia [158]... 

During the aerobic thermophilic treatment of sludge, ibuprofen and galaxolide were removed, respectively, 95% and more than 75% of initial concentrations after 20 days of incubation. However, even after 45 days incubation no complete elimination was observed [61]. Observations in composted sludge, which is considered to be an aerobic treatment, showed that several pharmaceuticals, including carbamazepine, diphenhydramine, fluoxetine, and triclosan, were not significantly removed by composting at mesophilic or thermophilic temperatures [148]. 

Makinen, P. M., Theno, T. J., Ferguson, J. F., Ongerth, J. E., and Puhakka, J. A., Chlorophenol Toxicity Removal and Monitoring in Aerobic Treatment Recovery from Process Upsets, Environ. Sci. Technol. 27 1434 (1993)... 

Makinen PM, Theno TJ, Ferguson JF, Ongerth JE, Puhakka JA (1993) Chlorophenol toxicity removal and monitoring in aerobic treatment recovery from process upsets. Env Sci Technol 27 1434-1439... 

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