Incrustations

Table A. I provides, for a particular rate of discharge in GPM. the friction loss in pipes for every 100 feet of straight pipe length, reasonably smooth and free from incrustation.

Calculation of the induction time is crucial, since gaining a stable and continuous process requires residence times in the mixer < precipitation induction times in order to prevent incrustation in the mixing device. The induction... 

Bekrustung, /. incrustation, bektimmem, v.t. afflict, trouble, bekupfern, v.t. copper. 

Beleg, m. covering, coating, lining plating incrustation floor proof document, -ana-tyse, /. analysis giving experimental proof check analysis. 

Gicht gas, n. gas from the top of a blast furnace, blast-furnace gas top gas, exit gas, mittel, n. remedy for gout. rauch, m. top smoke (of a blast furnace). -rose, /. peony, rhododendron, -riibe,/. bryony, -schwamm, m. incrustation near a furnace top (Zinc) tutty. staub, m. blast-furnace dust flue dust. 

Kesselstein, m. boiler scale compass brick, -ablagerung, /. deposit(ion) of boiler scale, -beseitigung, /. removal of boiler scale, -be-seitigungsmittel, n, (boiler) scale remover, disincrustant. -bilder, -bildner, m. (boiler) scale former, -bildung, /. (boiler) scale formation, incrustation. -gegenmittel, n. boiler compound, disincrustant. -kruste, /. incrustation of boiler scale. -losemittel, -losungamittel, n. (boiler) scale solvent, dis ... 

Kruste,/. crust, incrustation scab, scale, krusten-artig, a. crust-like, crusty, -bildend, a. 

Krusten-bildung, /. crust formation," incrustation. -tier, n. crustacean, krustieren, v.t. crust, incrust, krustig, a. crusty, crusted. 

The total consumption type of burner consists of three concentric tubes as shown in Fig. 21.5. The sample solution is carried by a fine capillary tube A directly into the flame. The fuel gas and the oxidant gas are carried along separate tubes so that they only mix at the tip of the burner. Since all the liquid sample which is aspirated by the capillary tube reaches the flame, it would appear that this type of burner should be more efficient that the pre-mix type of burner. However, the total consumption burner gives a flame of relatively short path length, and hence such burners are predominantly used for flame emission studies. This type of burner has the advantages that (1) it is simple to manufacture, (2) it allows a totally representative sample to reach the flame, and (3) it is free from explosion hazards arising from unbumt gas mixtures. Its disadvantages are that (1) the aspiration rate varies with different solvents, and (2) there is a tendency for incrustations to form at the tip of the burner which can lead to variations in the signal recorded. 

A different situation arises when one considers a stereospecific catalyst which is endowed with optical activity and which favors therefore a specific configuration. Such a catalyst, if highly stereospecific, should form polymers, for example of all d configuration with an occasional inclusion here and there of l units. Of course if a racemic mixture of such a catalyst is used, then formation of a racemic mixture of polymers is expected, each polymeric molecule having an all d configuration incrusted with l units or an all l configuration incrusted with d units. 

The design is further claimed to fully treat full flows of water in a single pass when installed direct to mains supplies, and water treated magnetically maintains its state for up to five days. Treatment results in hardness ions being attracted to other ions (rather than to pipework), resulting in a larger neutral body that has no ability to adhere to pipe walls or other contact surfaces, so that no incrustations or hard scales form. ... 

In some modern laundry formulations water hardness-promoting ions are bound to aluminosilicates. However, binding of hardness-promoting ions can only take place if these ions are solved in water. Because aluminosilicates or zeoliths are not soluble in water by themselves they are not able to solve insoluble salts of fatty acids already present in incrustations of fibers. For a suf-... 

FIGURE 16.13 Copper corrodes in air to form an attractive pale green layer of basic copper carbonate. This patina, or incrustation, passivates the surface, which helps to protect it from further corrosion. 

Shellac. Shellac is outstanding in that it is the only resin of animal origin. Shellac is a yellow, orange, or brown solid derived from lac, the secretion of the scale-like Kerria lacca insects that inhabit trees in areas of India and Thailand. To obtain the resin, twigs encrusted with the insect s secretion are cut down from the trees, the incrustation is removed from the twigs, coarsely... 

Lac is derived from lac resin, the hardened secretion of the lac insect, the only known resin of animal origin. The lac insect, Kerria lacca, formerly known as Laccifer lacca, is a natural parasite of a variety of trees in large areas of southern Asia. Three different products are derived from lac resin lac dye, lac wax, and shellac. To obtain the lac resin, twigs encrusted with the secretion of the insects are cut down from the trees, then the incrustation is separated from the twigs, washed with water, and filtered. The wax and shellac, which are insoluble in water, remain as a solid residue of the filtration, while the soluble red dye (lac) is obtained as a powder when the water from the filtered solution is evaporated. The coloring matter in lac dye is an organic compound known as laccaic acid. 

If the water then evaporates, the dry calcium bicarbonate decomposes, recreating calcium carbonate, which precipitates and forms hard deposits and incrustations while carbon dioxide and water are released into the atmosphere ... 

Polycarboxylates may also be added to increase dispersing power and so reduce the possibility of incrustations. Fine-tuning will again depend on the process details, the machine type and the degree of scouring necessary. 

Polycarboxylates may also be added to help prevent incrustations. It should be borne in mind, however, that magnesium is an essential component in most cases of stabilisation in peroxide systems, so any mixture of sequestrants should have minimum binding effect on this metal ion. 

Lignin may be defined as the incrusting material of the plant which is built up mainly, if not entirely, of phenylpropane building stones it carries the major part of the methoxyl content of the wood it is unhydrolyzable by acids readily oxidizable, soluble in hot alkali and bisulfite, and readily condenses with phenols and thio compounds (14). 

That some of the lignin, undoubtedly, is present in a free state in wood, is concluded from the fact that up to 10% of the total native lignin in the wood can be extracted with ethyl alcohol at room temperature. Further support for the incrustation theory is given by Nord in that an additional 23% of the native lignin in white Scots pine wood... 

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