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Pretreatment chemicals coagulants

Other pretreatment chemical feeds These include coagulants and flocculants. What is the nature of the chemical(s) being fed, the dosage, and how is the dosage controlled ... [Pg.239]

Zhu, B.T., Cliford, D.A., Chellam, S. (2005). Comparison of electrocoagulation and chemical coagulation pretreatment for enhanced virus removal using microfiltration membranes. Water Res. 39, 3098-3108. [Pg.262]

Dave et al. (1985) reported the biodegradation of toxic cyanide waste. The effluent was pretreated with hot alkah digestion and chemical coagulation followed by biological aeration. The HCN content in black gram and other seeds at a level of 1 mg/100 g flour was completely destroyed in 20-minute cooking (Dwivedi and Singh 1987). [Pg.322]

Small bubbles usually <100 pm diameter are found to be most effective in intercepting the su ended particles. For most applications some pretreatment with coagulating chemicals or flocculating agents is necessary to produce a floe vsbich will readily adhere to the bubbles. For aqueous sui ensions conventional water treatment chemicals are used preferably to give a small strong floe which is more likely to survive the shear forces in the liquid around the bubbles rather than larger deformable floes. [Pg.238]

A large number of commercial coagulants and synthetic flocculants are available with which to pretreat suspensions. While newer products have displaced the use of more traditional chemicals in recent years, few have been eliminated completely from the marketplace. The more important and widely used pretreatment chemicals are described here. [Pg.141]

Operational costs are primarily associated with power and vary from 50 to 120 hp/mgd. Pretreatment chemicals include coagulants, and when biofonhng is a problem, hypochlorite solution can be used on some membranes for cleaning. Citric acid can also be used for membranes that do not tolerate chlorine. Microfiltration membranes are typically not compatible with polymer addition, which is not reqnired, since even small pin floes cannot permeate the membranes. [Pg.86]

Keywords Additional discharge streams Antisealants Chemical treatment Coagulation/flocculation Concentration factor Dechlorination Filtration High recovery Membrane cleaning Pretreatment Recovery rate... [Pg.14]

Microfiltration (MF) and ultrafiltration (UF) membranes can be used as forms of pretreatment for nanofiltration (ISIF) or reverse osmosis (RO) desalination processes. Membrane pretreatment reduces the amount of chemicals that are required and hence reduces the environmental impact of the final discharge. MF membranes can be used to filter particles with diameters of 0.1-10 pmm and typically remove bacteria, viruses, precipitates, coagulates and large colloidal particles. UF can remove particles with diameters as small as 0.002 pm, and... [Pg.21]

Among the numerous approaches studied so far to minimize such phenomena in ED, it is worth citing pretreatment of the feed solution by coagulation (De Korosy et al., 1970) or microfiltration (MF) or ultrafiltration membrane processing (Ferrarini, 2001 Lewandowski et al., 1999 Pinacci et al., 2004), turbulence in the compartments, optimization of the process conditions, as well as modification of the membrane properties (Grebenyuk et al., 1998). However, all these methods are partially effective and hydraulic or chemical cleaning-in-place (CIP) is still needed today, thus... [Pg.301]

Latex gloves, balloons, condoms, and other elastomeric products are produced by dipping metal molds into a latex that can consist of either natural or synthetic rubber. The mold is pretreated with a chemical that causes the latex to coagulate on the mold. Then the latex-covered mold passes through an oven where the elastomer cures (crosslinks). A modem factory can produce on the order of a million latex gloves or balloons a day. [Pg.129]

Chemical application dosages and controls should be checked to ensure proper feeding of chemical. This includes acid/caustic, chlorine or other oxidizer, coagulant in pretreatment, and antisealant. [Pg.285]

Depending on the nature of the product, pretreatment of the feed material may be desirable to improve the separation characteristics. Possible techniques are based on chemical or physical treatment and include thickening, flocculation, and coagulation. A simple heat treatment process where the temperature of the broth is elevated and held for a period of time can reduce... [Pg.639]

After a pretreatment step, followed by a preozonation, a physico-chemical process (coagulation-flocculation, settling and sand filtration) removes the suspended solids and colloids of water. Then the dissolved organic compounds are oxidised and adsorbed with their by-products on active carbon. Before leaving the plant, a last oxidation step allows the disinfection of the produced water and to assure its sanitary protection along the distribution network, until its consumption. [Pg.187]


See other pages where Pretreatment chemicals coagulants is mentioned: [Pg.113]    [Pg.712]    [Pg.356]    [Pg.146]    [Pg.149]    [Pg.60]    [Pg.62]    [Pg.154]    [Pg.318]    [Pg.374]    [Pg.360]    [Pg.173]    [Pg.732]    [Pg.19]    [Pg.154]    [Pg.318]    [Pg.315]    [Pg.128]    [Pg.374]    [Pg.343]    [Pg.315]    [Pg.341]    [Pg.315]    [Pg.180]    [Pg.315]    [Pg.381]    [Pg.245]    [Pg.459]    [Pg.2774]    [Pg.271]    [Pg.101]    [Pg.217]    [Pg.270]   
See also in sourсe #XX -- [ Pg.141 ]




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