Sewage, effluent sludge

As a result of several studies, the following conclusions regarding viruses in sewage warrant consideration (1) primary sewage treatment has little effect on enteric viruses (2) secondary treatment with trickling filters removes only about 40 percent of the enteroviruses (3) secondary treatment by activated sludge treatment effectively removes 90 percent to 98 percent of the viruses and (4) chlorination of treated sewage effluents may reduce, but may not eliminate, the number of viruses present. 

Was this your answer Primary treatment uses settling basins to remove the bulk of solid waste and sludge from sewage effluent. Secondary treatment uses aeration to decrease effluent BOD.Tertiary treatment removes pathogens and wastes not removed by eariieT treatments by filtering effluent through powdered carbon or other fine particles. 

Lee, H.B. and T.E. Peart. 2002. Determination of bisphenol A in sewage effluent and sludge by solid-phase and supercritical fluid extraction and gas chromatography/mass spectrometry. /. AOAC Int. 83 ... 

Peracetic acid is a particularly powerful biocide used for disinfection of raw or partially treated sewage effluents and sewage sludge. Peracetic acid can also be successfully used for the disinfection of drinking water.50... 

Riekerk, H. and Zasoski, R.J., Effects of dewatered sludge applications to a Douglas fir forest soil on the soil, leachate, and groundwater composition, in Utilization of Municipal Sewage Effluent and Sludge on Forest and Disturbed Land, Sopper, W.E. and Kerr, S.N., Eds., Pennsylvania State University Press, University Park, 1979, p. 35. 

DeWalle FB, Kalman DA, Dills R, et al. 1982. Presence of phenolic compounds in sewage effluent and sludge from municipal sewage treatment plants. Water Sci Technol 14 143-150. 

Published by Water Research centre, U.K. Covers all commercial, technical and scientific aspects of water and wastewater industries, including water quality, sewage and sludge treatment, industrial effluent treatment, and water pollution. Covers publications 1960 to dale. 

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