Coagulation process

Table 1 Hsts a number of common inorganic coagulants. Typical iron and aluminum coagulants are acid salts that lower the pH of the treated water by hydrolysis. Depending on initial raw water alkalinity and pH, an alkah such as lime or caustic must be added to counteract the pH depression of the primary coagulant. Iron and aluminum hydrolysis products play a significant role in the coagulation process, especially in cases in which low turbidity influent waters benefit from the presence of additional colHsion surface areas.

The first five of these techniques involve deformation and this has to be followed by some setting operation which stabilises the new shape. In the case of polymer melt deformation this can be affected by cooling of thermoplastics and cross-linking of thermosetting plastics and similtir comments can apply to deformation in the rubbery state. Solution-cast film and fibre requires solvent evaporation (with also perhaps some chemical coagulation process). Latex suspensions can simply be dried as with emulsion paints or subjected to some... 

In the rennet coagulation process fresh skimmed milk is adjusted to a pH of six and about 40 ounces of a 10% solution of rennet are added per 100 gallons of milk. The initial reaction temperature is about 35°C and this is subsequently raised to about 60°C. The coagulation appears to take place in two stages. Firstly the calcium caseinate is converted to the insoluble calcium paracaseinate and this then coagulates. 

Great care is essential in controlling the temperature and the coagulation process as otherwise impurities, particularly other proteins, will be brought down with the casein. Such impurities will adversely affect the transparency of the product. 

Before the advent of sophisticated polymer technology, sodium alu-minate and sodium silicates (plus caustic) were sometimes used in both external and internal coagulation processes. 

Figure 8. Chromatographs showing the effect of a coagulation process. Higher elution volume peak represents the original sample while the lower elution volume peak represents the coagulation recovered material.

The six major proteins of milk, asl-, o s2-, and /c-casein, jS-lactoglobulin, and a-lactalbumin, contain at least one tryptophan residue [57], the fluorescence of which allows the monitoring of the structural modifications of proteins and their physicochemical environment during the coagulation processes. Emission fluorescence spectra of the protein tryptophanyl residues were recorded for the milk coagulation kinetics induced by... 

Structural Evolution During the Three Different Coagulation Processes... 

Brillas E, Casado J (2002) Aniline degradation by electro-Fenton and peroxi-coagulation processes using a flow reactor for waste water treatment. Chemosphere 47(3) 241-248... 

Several substances that contribute to the blood coagulation process are formed in the liver. These include fibrinogen, prothrombin, and several of the blood clotting factors (II, VII, IX, and X). Deficiency in any of these substances leads to impaired blood coagulation. 

Sheehan and coworkers [47] have also prepared a novel isocyanide derivative, which was used in an Ugi-4CR to prepare noncovalent inhibitors of factor Xa, a key element in the coagulation process [48]. 

Crepe rubber of lower quality than pale crepe it is made from the pre-coagulated lumps which form in the latex before the coagulation process is carried out. 

Also, the figures contain nephelometric curves for the product t (that is, for p + s, in the proportions formed in the synthesis) and the fraction o, which was also a thermally precipitating product and deposited onto the walls of the reaction vessel in the course of the copolymerization of NVC1 with NVIAz at their initial molar ratio of 85 15 (Table 1). One can see that the precipitation behaviour of the total product t differs, although the amount of the s-fraction is almost the same at 31-33%. Obviously, this depends on the properties of the s-fraction. For instance, the heat-induced precipitation of the sample t formed from the feed with a comonomer molar ratio of 90 10 (Fig. 3b) is suppressed by the presence of its own s-fraction to a markedly lesser extent when compared to the product t obtained at the comonomer molar ratio of 85 15 (Fig. 3a). Most likely, such differences reflect the divergent influence of the s-fractions on the coagulation processes in the thermo-precipitating fractions of the total product t. These differences, for example different surface... 

While the system conforms to coagulation in a secondary minimum, the redispersion region is best accounted for in terms of gel formation originating from the rod-like shape of the particles and hydrated surface. During the final coagulation process additional attractive forces such as dipolar and hydrogen bonding form floes which are irreversible and denser than those formed at a lower salt concentration. 

As will be shown in this report, polymer fibres gain additional strength by an increase of the molecular weight and by a more contracted orientation distribution, i.e. a higher modulus. For the wet-spun fibres, a strength increase can be achieved by improvement of the coagulation process, which makes for a more uniform structure and chain orientation in the cross section of the fibre, and by a reduction of the amount of impurities. 

Process Iron in raw wastewater [mg/dm3] Iron added for coagulation process [mg/dm3] Iron in waste-water after coagulation [mg/dm3] Iron transferred to postcoagulation sludge [%]... 

Kinetic methods describing the evolution of distributions of molecules by systems of kinetic differential equations (obeying either the classic mass action law of chemical kinetics or the generalized Smoluchowski coagulation process). 

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