Plant sewage

Methane also is commonly produced by the decomposition of organic matter by a variety of bacterial processes, and the gas is used as a fuel in sewage plants (see Water, sewage). Methane also is called marsh gas because it is produced during the decay of vegetation in stagnant water. 

Filter Beds. The sprinkling filter beds of sewage plants are composed of closely screened mineral aggregate of 38—64 mm or 51—76 mm that meet a severe soundness test. Much of this requirement is suppHed by dense, fine-grained, hard limestone and dolomite. 

Vitamin B12 has been synthesized from scratch in the laboratory, but bacteria growing on sludge from municipal sewage plants do a much better job. 

Some years ago, comparative investigations into the biodegradation of secondary alkanesulfonates using 14C-labeled preparations [106] and radiometric studies of the biodegradation of secondary alkanesulfonates in a sewage plant model [107] are published (Fig. 42). 

Biological treatment Used in all sewage plants and many settling ponds. 

It was mentioned that nitrite does not seem to accumulate in soils under most conditions, and the same generalization seems to be true for natural waters. Dressel reported N02" levels of up to 1 ppm in rivers (although considerably higher levels were detected in effluents of an experimental sewage plant and of a galvanizing plant). Keeney, found that... 

Biodegradation of diisopropyl methylphosphonate was not observed in acclimated cultures of bog water obtained from the RMA, even after the addition of extra carbon sources and an incubation period of up to 12 weeks (Spanggord et al. 1979). In addition, no biodegradation of diisopropyl methylphosphonate was observed in waters obtained from the Palo Alto sewage plant aeration tank or from a pond near Searsville Lake in Woodside, California. 

Kepro [Kemira process] A process for recovering valuable products from municipal sewage sludge. It makes four products crude iron phosphate, a biofuel, water treatment chemicals, and a carbon source for denitrification in the sewage plant. Developed by Kemira Chemicals in the 1990s and first installed in Helsingboig, Sweden... 

EWPCA (European Water Pollution Control Association) (1982), Proceedings ofEWPCA International State-of-the-art Seminar on Corrosion in Sewage Plants, Hamburg, January 28-29, 1982. 

A Type 11 enclosure is suitable for application indoors where the equipment may be subject to corrosive acid or fumes, as in chemical plants, plating rooms, sewage plants, etc. The apparatus may be immersed in oil. 

Information gathering The town s sewage plant discharge is located near the section of the river could the chlorine concentration from the treatment facility be too high Even low levels can be toxic, not only to fish directly, but also to many organisms lower in the food chain that would ultimately kill the fish. 

Interpretation/report The fish in the cage survive, eliminating chlorine and anything else in the sewage plant discharge as the culprit. 

Not only the extreme amounts of surfactants emitted into sewage plants and thereby into surface waters, but also the broad variety of the chemical structures combined with their excellent water solubility, their surface-active nature and the persistence of some of the known metabolites make them a group of environmental pollutants that need to be addressed with high priority. For some of the compounds, an enormous impact on the ecosystem, e.g. on fish, can be shown. 

In the area of agriculture and food industry as well as the public sewage plants there are increasingly problems because of odour nuisance in the neighbourhood. The substances emitted from the different processes are seldom noxious. They are many individual components of very low concentration which together result in a specific odourous mixture. And this is felt to be penetrating and intolerable. This refers in particular to odours from... 

Fig. 8 Bioscrubbers for the sludge stabilization of a sewage plant—central version...

ZEMAN, A., and HAGENGUTH, H., (1980) Identification of Odorous Compounds in Emissions from Municipal Sewage Plants by GC-MS. German Armed Forces... 

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