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Environment water treatment

Environment Water treatment was chrome-zinc for the first 6 years and orthophosphate for the next 5 years. Free residual chlorine 0.1-0.3 ppm filtered orthophosphate 10-17 ppm, 6-8 cycles calcium <200 ppm, 200°F (93°C), pressure 50 psi (0.3 MPa). [Pg.112]

Water and the environment must be periodically monitored for these quality attributes, and in some instances the results are not available for days after the sample is obtained. Meanwhile, the water would have been used to manufacture a great number of pharmaceutical products or else the products would have already been exposed to the environment. Water treatment and air handling systems are highly dynamic, and careful attention has to be paid to their operation, even though this may sometimes be somewhat unreliable. Consequently, they must be validated and then closely monitored and controlled. [Pg.438]

Water Treatment. Flotation in water treatment is used both for the removal of dissolved ions such as Cu ", Cr ", or (PO or surfactants and suspended soHds as in the case of sludge treatment. The final product in this case is purified water rather than a mineral concentrate. Furthermore, water is treated either for drinking purposes (potable water preparation) or safe disposal to the environment. [Pg.52]

Functional derivatives of polyethylene, particularly poly(vinyl alcohol) and poly(acryLic acid) and derivatives, have received attention because of their water-solubility and disposal iato the aqueous environment. Poly(vinyl alcohol) is used ia a wide variety of appHcations, including textiles, paper, plastic films, etc, and poly(acryLic acid) is widely used ia detergents as a builder, a super-absorbent for diapers and feminine hygiene products, for water treatment, ia thickeners, as pigment dispersant, etc (see Vinyl polymers, vinyl alcohol polymers). [Pg.479]

Environment Internal Well water 95°F (35°C), pH 7.9, sulfate 900 ppm, chloride 330 ppm, molybdate water treatment External Steam and condensate... [Pg.234]

Environment Internal Cooling water phosphonate and zinc water treatment... [Pg.236]

The corrosion rates of nickel and nickel alloys in pure water and steam at elevated temperatures are generally extremely low, typically of the order of 1 m/year. The metal and its alloys are therefore often selected for service in these environments in circumstances where contamination of the water by metal ions is to be avoided. It should be noted, however, that the possibility of stress corrosion may need to be taken into account in certain circumstances (see below). Additionally where phosphate water treatment has been used in PWR secondary heat exchangers, severe localised corrosion has occurred when alkaline phosphates have been permitted to accumulate . [Pg.794]

BSI recommends in the table of water treatment for hot water systems that chromate inhibitors should not be used because of their undesirable impact on the environment. It should also be noted that some treatment chemicals are microbiologically degraded in storage. [Pg.580]

This review mostly summarizes the scientific information available in developed countries, where the prevalence of diseases associated with water use is kept under very acceptable levels. However, there are reasons to think that the situation might worsen as a consequence of the effects of the climatic change, the increase of population in certain areas and the deterioration of sanitation infrastructures. It may be necessary to take new measures to maintain the present situation. Better knowledge of the water-borne pathogens, where they originate, how they persist or replicate in the environment, how they survive water treatments, and how they are transported in water and soil, will allow us to take the necessary measures to prevent the effects of water scarcity as well as the effects of extreme climatic events foreseen for the future by the experts in climatic change [13]. [Pg.149]

Huerta-Fontela M, Galceran MT, Ventura E (2008) Stimulatory drugs of abuse in surface waters and their removal in a conventional drinking water treatment plant. Environ Sci Technol 42(18) 6809-6816... [Pg.223]

Concentrations found in leachate do not necessarily represent the concentrations that would be foimd in the wider environment. Landfill leachate may be treated using on-site water treatment facilities, it may be disposed of directly to the municipal sewer, or, in some cases — for older facilities — it may leach directly out of the landfill into the environment. Even in the latter case, there will be a significant dilution of the landfill leachate upon entering the environment. Resulting environmental concentrations are, therefore, likely to be significantly lower than those reported above. [Pg.17]

Acero JL, K Stemmier, U van Gunten (2000) Degradation kinetics of atrazine and its degradation products with ozone and OH radicals a predictive tool for drinking water treatment. Environ Sci Technol 34 591-597. [Pg.38]

Analytical chemistry is an important field in the life sciences whether the main focus is health (pharmaceutical chemistry), nutrition (food chemistry), food supply (pesticide chemistry), environment (water chemistry, waste minimization, disposal or treatment) or lifestyle (textiles, mobility, cosmetics). Thus chemists (and other scientists) working analytically, whether they are trained originally as analytical chemists or whether they come from a different field and use analytical chemistry as support for their research area, play an important role in supporting the progress in the life sciences. [Pg.51]

STABREX is easier and simpler to use compared to any other oxidant available for industrial water treatment. The product is pumped directly from returnable transporters (PortaFeed Systems)17 with standard chemical feed equipment. Previously, the only practical ways to apply bromine were to oxidize bromide solutions on-site with chlorine in dual liquid feed systems, or with one of the solid organically-stabilized bromine products applied from sidestream erosion feeders. The former is cumbersome and complex, and the latter is prone to dusting and difficult to control. Other oxidants require complex handling and feed of toxic volatile gases, unstable liquids, multiple-component products, or reactive solids. Simplicity in use results in reduced risk to workers and to the environment. [Pg.59]

The environmental fate of chemicals describes the processes by which chemicals move and are transformed into the environment. Environmental fate processes that should be addressed include persistence in air, water and soil reactivity and degradation migration in groundwater removal from effluents by standard waste-water treatment methods and bioaccumulation in aquatic or terrestrial organisms. [Pg.48]

Unitika is a Petrochemical company created in 1889 and which has grown especially into the textile business. Today, their business covers a wide range of economical areas, including financial activities. Its environmental division provides facilities for water treatment, incinerators, air pollution prevention facilities and heavy metal fixing agents. Their R D center conducts research to develop new business areas and products in four segments polymers, environment, advanced materials, and health. [Pg.360]

The mobility of arsenic compounds in soils is affected by sorp-tion/desorption on/from soil components or co-precipitation with metal ions. The importance of oxides (mainly Fe-oxides) in controlling the mobility and concentration of arsenic in natural environments has been studied for a long time (Livesey and Huang 1981 Frankenberger 2002 and references there in Smedley and Kinniburgh 2002). Because the elements which correlate best with arsenic in soils and sediments are iron, aluminum and manganese, the use of Fe salts (as well as Al and Mn salts) is a common practice in water treatment for the removal of arsenic. The coprecipitation of arsenic with ferric or aluminum hydroxide has been a practical and effective technique to remove this toxic element from polluted waters... [Pg.40]

Scott JP, Ollis DF (1995) Integration of chemical and biological oxidation processes for water treatment review and recommendations. Environ Prog 14 88-103... [Pg.151]

The high amounts in which these substances are consumed and produced have conferred illicit drugs and their human metabolites a pseudo-persistent character in the environment. Like over-the-counter and prescribed pharmaceuticals, illicit drugs are metabolized after consumption and different proportions of the parent compound and metabolic by-products are excreted via urine or feces and flushed into the sewage system toward wastewater treatment facilities, if existing. However, these substances are poorly or incompletely removed by conventional waste-water treatment processes [2, 3]. As a consequence, illicit drugs and metabolites are continuously introduced via wastewater treatment plant (WWTP) effluents into the aquatic media. In fact, this constitutes the main route of entry of this type of compounds into the environment as direct disposal is unlikely. [Pg.190]

The latter concept implies providing local life support systems for unfriendly environments. By now, Ukrainian scientists and engineers have developed a variety of processes for potable water treatment by adsorption, electrochemical oxidation, electrocoagulation, electro-coprecipitation, electrodialysis, electrofloatation, floatation, membrane techniques etc. Each family must get small units for water purification, air cleaning and removal of hazardous substances from the food as soon as possible, for it may take decades to introduce cleaner production on a national scale. Here, we should follow the example of Western business people who bring with them to Ukraine devices enabling a safe existence in this unfriendly environment. [Pg.32]


See other pages where Environment water treatment is mentioned: [Pg.346]    [Pg.346]    [Pg.318]    [Pg.36]    [Pg.303]    [Pg.472]    [Pg.264]    [Pg.319]    [Pg.281]    [Pg.2518]    [Pg.438]    [Pg.369]    [Pg.847]    [Pg.147]    [Pg.152]    [Pg.137]    [Pg.294]    [Pg.885]    [Pg.1394]    [Pg.581]    [Pg.308]    [Pg.93]    [Pg.5]    [Pg.129]    [Pg.352]    [Pg.58]    [Pg.401]    [Pg.745]    [Pg.44]   
See also in sourсe #XX -- [ Pg.26 , Pg.63 , Pg.67 ]




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