Treatment processes, drinking water

Similar to the treatment of drinking waters, though, a near-to-complete mineralization of the DOC cannot be achieved economically, and combination of ozonation with other processes is recommended. The success of the treatment scheme should be measured by the over-all DOC-removal. 

Hoigne J (1998) Chemistry of Aqueous Ozone and Transformation of Pollutants by Ozonation and Advanced Oxidation Processes, in The Handbook of Environmental Chemistry Vol. 5 Part C, Quality and Treatment of Drinking Water II, ed. by J Hrubec, Springer- Verlag, Berlin, Heidelberg. 

Ozone is used in the treatment of drinking water and in industries where high purity water is required (e.g., breweries, pharmaceuticals, and electronics). Ozone is also used in industrial wastewater pollution control, wastewater disinfection, and odor control in the treatment of process water, such as cooling tower water in the treatment of swimming pools and spas in pulp bleaching and in organic synthesis, as a selective oxidant. 

An alternative to sedimentation for removing suspended solids is flotation. This tends to be used for low-density particles that tend to float anyway during conventional sedimentation processes. Drinking water examples include algae and floes of humic and fulvic acids that result from the treatment of coloured waters [549]. Wastewater examples include fatty materials, pulp fibres, and oils that can be floated... 

Purified water is typically prepared by ion exchange, reverse osmosis or a combination ofthe two treatment processes. Purified water is intended for use as an ingredient in the preparation of compedial dosage forms. It contains no added substances, and is not intended for use in parenteral products. It contains no chloride, calcium, or sulfate, and is essentially free of ammonia, carbon dioxide, heavy metals, and oxidizable substances. Total solids content will be no more than 10 ppm, pH will be 5-7, and the water will contain no coliforms. The United States Pharmacopoeia National Formulaiy (USP) requires that purified water comply with EPA regulations for bacteriological purity of drinking water (40 CFR 141.14, 141.21). Table 4 is a quantitative interpretation of United States Pharmacopoeia XXI standards for purified water. ... 

Mofidi AA, Min JH, Palencia LS, Coffey BM, Liang S, Green JF (2002) Task 2.1 Advanced oxidation processes and UV photolysis for treatment of drinking water. Report. California Energy Commission Sacramento, California, USA Liang S, Yates RS, Davis DV, Pastor SJ, Palencia LS, Bruno J-M (2001) J Am Water Works Assoc 93 110... 

Hoign4 J (1998) Chemistry of aqueous ozone and transformation of pollutants by ozonation and advanced oxidation processes. In Hrubec J (ed) The Handbook of Environmental Chemistry, vol 5. part C. Quality and Treatment of Drinking Water 11. Springer, Berlin Heidelberg New York... 

Coagulation process is very similar to that discussed in the advanced primary treatment and drinking water purification (see Chapter 10). 

In slow-rate filtration biological, physical and chemical purification processes take place in the sandy filtration layer and thus, top quality water with preserved biological values is obtained. Therefore, this process is used for the treatment of drinking water. 

In this chapter, the key processes that affect the formation and fate of transformation products in wastewater treatment and drinking water treatment are discussed. 

Clarification of water The treatment of drinking water provides multiple barriers to protect public health by removing microorganisms, and natural and man-made chemicals that may cause illness in consumers. Generally, a conventional treatment process employs coagulation/flocculation-sedimentation-filtration, and various modifications of the above configuration can be adopted based on specific needs. Aluminum- and iron-based chemicals, particularly alum (Al2( 504)3 I8H2O) and iron(III) chloride. 

PFCs also used in the drinking water treatment process are membrane and activated carbon filtration. The difference in PFC baseline concentrations in drinking water will depend on the technologies used in different treatment plants. Drinking water prepared by a treatment which does not include GAC filtration or reverse osmosis will generally contain higher PFCs levels in the case contaminated water is used as source water. 

Van Der Bruggen B, Vandecasteele C et al (2003) A review of pressure-driven membrane processes in wastewater treatment and drinking water production. Environ Prog 22(l) 46-56... 

Van Der Bruggen, B., et al., Review of Pressure-Driven Membrane Processes in Wastewater Treatment and Drinking Water Production. Environmental Progress, 2003,22(1), 46-56. 

An additional problem related to conventional treatments of drinking water shorrld also be considered, namely, the presence in final treated waters of new disinfection by-products (DBFs) produced drrring the treatment processes. 

Cheremisinoff, N. P. 2001. Handbook of Water and Wastewater Treatment Technologies. Boston, MA Butterworth-Heinemann. A handbook aimed at process and plant engineers, water treatment operators, and environmental consultants, this reference contains practical information for the treatment of drinking water and wastewater. 

Polyacrylamide, produced from monomeric acrylamide (2-propenamide), has been used for decades in various industrial processes, e.g., as a flocculant in the treatment of drinking water. Especially for reasons of occupational health and safety, numerous toxicological studies on acrylamide have already been conducted. These studies have shown above all that on high exposure, acrylamide (i) binds to hemoglobin in the blood, (ii) is metabolized to reactive epoxide glycidamide and (iii) is carcinogenic on chronic exposure in animal tests. For this reason, acrylamide was put about 20 years ago... 

A large variety of processes are used to treat water and are discussed in this chapter. Some of these are physical processes including filtration, aeration, and adsorption on solids such as activated carbon. Chemical processes used include acid-base, precipitation, oxidation-reduction, and com-plexation. Treatment of drinking water almost always involves physical and chemical processes, whereas wastewater treatment usually uses all three processes with a heavy reliance on biological treatment. 

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