Coagulation filtration

Another possible modification is the use of seawater as the regenerant. Even though it contains calcium and magnesium, but only 2.7 wt % NaCl, it sometimes can be purified by coagulation, filtration, and chlorination less expensively than salt can be purchased. The lower concentration reduces the regeneration efficiency by 40—50%. 

Color None Decaying organic material and metallic ions causing color may cause foaming in boilers hinders precipitation methods such as iron removal, hot phosphate softening can stain product in process use Coagulation, filtration, chlorination, adsorption by activated carbon... 

Color Boiler foaming Presents problems with iron removal Discoloration of mantifactured produce Adsorption (activated carbon Coagulation Filtration Chlorination... 

Coagulation factor products, 12 139 Coagulation factors, 72 144-145 Coagulation/filtration, for arsenic removal, 3 280t, 281-282... 

With a chapter on particle-particle interaction (coagulation) the characteristics of particles and colloids as chemical reactants are discussed. Since charge, and in turn the surface potential of the colloids is important in coagulation, it is illustrated how in simple cases the modelling of surface complex formation permits the calculation of surface charge and potential. The role of particle-particle interaction in natural water and soil systems and in water technology (coagulation, filtration, flotation) is exemplified. 

SOME WATER-TECHNOLOGICAL CONSIDERATIONS IN COAGULATION, FILTRATION, AND FLOTATION... 

Tertiary treatment or add-on processes can be applied to the existing technology. This usually consists of coagulation, filtration, granular carbon adsorption, or chemical oxidation. The major disadvantage of tertiary treatment is that the processes are nonpollutant specific. For example, if the pollutant to be removed is dichlorophenol, GAG, or ozonation, tertiary treatment will remove most other organics (COD) as well asDCP. 

UV can also be used in water reclamation and reuse. An example is the reclamation of swimming pool water. Usually, the swimming pool water reuse process includes coagulation, filtration, clarifier, disinfection, and pH adjustment. The conventional swimming pool disinfection chemical is chlorine however, high concentrations of residual chlorine can be harmful to human health. The UV technology can be placed between the filters and chlorine disinfection unit as a pre-disinfection unit and remove pathogens. Hence, much less amount of chlorine (compared with the process without UV unit) is needed for residue disinfectant level. 

BAT for inorganic compounds coagulation/ filtration f, granular activated charcoal, lime softening6, reverse osmosis6 ... 

Each type of raw water requires a specific treatment. The best quality water is merely disinfected polluted surface water usuaUy needs treatment by coagulation, filtration and disinfection. Seriously contaminated water is used only in unavoidable cases because of the difflculties involved in its treatment. 

For water clarification, systems with sludge sedimentation are used, as well as coagulation filtration and separation of suspended particles in a cloud of floccules. 

Coagulation filtration is recommended for the treatment of raw water with a relatively low content of suspended particulate matter. The coagulant supply is connected to the piping in front of the filter water inlet. The perikinetic stage of coagulation takes place in the piping and in the upper part of the filter the orthokinetic stages take place in the filtration bed where floccules of hydroxide are trapped. 

Usually, in a conventional coagulation-filtration process for arsenic removal, the addition of the coagulant is followed by a short rapid-mix step followed by a slow-mix step for flocculation. Flocculation is usually followed by sedimentation and filtration. To do away with the multitude of steps required in the conventional process, the authors designed and tested a simplified iron coagulation-direct mi-croflltration process, as described below (3,4). 

The particles being accessible to direct observation by counting and by coagulation, filtration, and weighing, w can be found. The only unknown is MU which is thus calculable. 

The depth penetration of material in coagulation-filtration is almost opposite to the concept of using the filter as a screen. Precipitation initiated by germs plays a significant role. Empirical relations are normally relied on in the design of filters as a function of the penetration in depth of coagulated material. The concentration of those residual matters in filtered water (C,) depends on several factors the linear infiltration rate (Vf), the effective size of the filter medium (ES), the porosity of the filter medium (e), the final loss of head of the filter bed (Ah), the depth of penetration of the coagulated matter (/), the concentration of the particles in suspension in the... 

Example 1 of Reference 34 describes a four-polymer IPN. A seed latex of butyl acrylate and 1,3-butylene dimethacrylate forms Cn. Onto this seed latex core, a shell of methyl methacrylate and glycidyl methacrylate are polymerized, forming P2. After coagulation, filtration, and washing, the resulting powder is dispersed in styrene and a stoichiometric amount of methacrylic acid. The dispersion is heated until the reaction between the methacrylic acid and the epoxy groups on the graded elastomeric particles is at least 50% complete. 

Prior purification of the water if needed (clarification-coagulation, coagulation-filtration). 

Figure 6.11. Generic coagulation/filtration process flow diagram (adapted from USEPA, 2003).

Coagulation/filtration - Creation of sludge or solid wastes concentrated with contaminants ... 

Coagulation-filtration is a much more effective procedure than filtration alone for the removal of suspended material from water. As the term implies, the process consists of the addition of coagulants that aggregate the particles into larger-size particles, followed by filtration. Either alum or lime, often with added polyelectrolytes, is most commonly employed for coagulation. 

I step of water purification includes initial ozonation, coagulation, filtration (serial structures),... 

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