[...]... organisms and selecting those that show a maximum rate of biodegradation with maximum substrate utilization and minimum microbial biomass production Content Biotechnology for Industrial and Municipal Wastes 3 Wastewater Treatment Biological treatment is one of the most widely used removal methods as well as for partial or complete stabilization of biologically degradable substances in wastewaters and wastes... support media (sand or rocks) and the wastewater flows around it Aerobic suspended contact systems the activated sludge process, its variations and aerobic lagoons comprise this group In this group both biomass and substrate are in suspension or motion Content 6 Biotechnology for Waste and Wastewater Treatment Anaerobic suspended contact systems anaerobic sludge digestion, anaerobic lagoons, and latter... incoming wastewater is mixed and aerated with existing biological sludge (microorganisms) Organics in the wastewater come into contact with the microorganisms and are utilized as food and oxidized to CO, and H,O As the microorganisms use the organics as food they reproduce, grow, and die As the Content 10 Biotechnology f o r Waste and Wastewater Treatment microorganisms grow and are mixed together by... wastes Suspended, colloidal or dissolved degradable organic material, quantities and ratios depend on the nature of the wastewater Characteristics of wastewaters are measured in terms of Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD), and Volatile Suspended Solids (VSS) Most biological waste and wastewater treatment processes employ bacteria as primary microorganisms; certain other microorganisms... oxygen protection for receiving waters Clean water demand has increased more rapidly than population This has given rise to the supply of complete treatment plants for small communities, developments, and isolated installations by manufacturers of waste treatment equipment in the form of packaged plants A conventional scheme for wastewater treatment is illustrated in Figure 1 The pretreatment stage often... Content 4 Biotechnology for Waste and Wastewater Treatment Cell material synthesis CGHGO3 + NH3 + 0 2 -+ CSH7NOz + CO2 + H2O Cell material oxidation C5H7N02 NH3 + + 5C0, + 2H,O + energy Various conventional methods that are used in biological treatment are listed in Table 1 along with the treatment agents and typical wastes that are treated TABLE 1 METHODS OF BIOLOGICAL TREATMENT Process Treatment. .. United States Content 20 Biotechnology for Waste and Wastewater Treatment MIXING influent (o,L.) c RETURN waste organisms A S/AV ANAEROBIC ACTIVATED SLUDGE PROCESS effluent c contact media influent ANAEROBIC FILTER PROCESS Figure 8 Anaerobic process designs Content Biotechnology for Industrial and Municipal Wastes 21 TABLE 4 TYPICAL SLUDGE VOLUME PRODUCED BY CONVENTIONAL TREATMENT PROCESS Process... manganese, iron, calcium, nickel, and cobalt Other bacteria produce complexing agents which selectively extract metals from dilute solutions Algae concentrate silica and green-brown algae and fungi concentrate zinc and other heavy metals Mosses and higher plants concentrate mercury, nickel, zinc, uranium, cesium, and strontium Content 22 Biotechnology for Waste and Wastewater Treatment UNIT PROCESS THICKENING... be a form of secondary treatment and normally follows a primary settling basin The flow diagram for a typical activated sludge treatment process is illustrated in Figure 2 There are several variations to this process including conventional arrangements, the contact stabilization process, and the step aeration process Examples of these are given in Figure 3 Content 8 Biotechnology for Waste and Wastewater. .. applications for the pollution engineer Natural decomposition of inorganic and organic materials has occurred for millions of years Biological management of waste has been practiced for thousands of years Most microorganisms in use are extracted from soil and water bodies and more recently technically developed for specific applications, and uses organic and toxic materials as sources of energy and carbon . Nicholas P. Biotechnology for waste and wastewater treatment / Nicholas P. Cheremisnoff. p. cm. Includes bibliographical references and index. 1 400%. 1 Content 2 Biotechnology for Waste and Wastewater Treatment Researchers, involved in training bacteria Bacillus megaterium and Nocardiopsis to