Mineralization additive product effects

The foundry industry is a major player in the recycling of metals. Steel, east iron and aluminium scrap is remelted into new products. Most possible negative enviromnental effects of foundries are related to the presence of a thermal process and the use of mineral additives. Enviromnental effects therefore are mainly related to the exhaust and off-gases and to the re-use or disposal of mineral residues. 

Thompson et al. (24) also verified that the addition of trace minerals to potato process effluents has little effect on surfactinproductionby B. subtilis ATCC 21332. In fact, the addition of com steep liquor had a detrimental effect on biosurfactant production, whereas the addition of trace minerals had no effect on surface tensions. On the other hand, growth rates were marginally higher with added nutrients. 

For waterborne paint systems (especially emulsions used for decorative purposes) defoamers based on mineral oils are often used. In addition to the mineral oil as carrier, these products contain finely dispersed hydrophobic particles (e.g., silica, metal stearates, polyureas) as defoaming components. A small amount of silicone is sometimes included to intensify the defoaming action. For high-quality waterborne coatings in industrial applications, defoamers are used that contain hydrophobic silicone oils as the principal defoaming component instead of mineral oils. They have a better defoaming effect, but are more expensive. In most cases silicone defoamers do not cause the gloss reduction that is often observed with mineral oil products. 

As aforementioned, the efflorescence is not harmful for the durability of concrete. When the mechanism involved in efflorescence formation is known, the remedies of effective preventing its occurrence are also possible. For example cements with mineral additions can be used in the production of concrete elements. Silica fume has particularly beneficial effect, which prevents efflorescence already from 5 % addition. The groimd granulated blastfurnace slag or siliceous fly ash are good additives too. The latter one should be groimd when added to concrete or taken from the last section of electrical precipitator, where the finest fractions are collected. 

Impurities in mineral fillers can have serious effects. Coarse particles (grit) will lead to points of weakness in soft polymers which will therefore fail under stresses below that which might be expected. Traces of copper, manganese and iron can affect the oxidative stability whilst lead may react with sulphur-containing additives or sulphurous fumes in the atmosphere to give a discoloured product. 

The elements of Group 5 are in many ways similar to their predecessors in Group 4. They react with most non-metals, giving products which are frequently interstitial and nonstoichiometric, but they require high temperatures to do so. Their general resistance to corrosion is largely due to the formation of surface films of oxides which are particularly effective in the case of tantalum. Unless heated, tantalum is appreciably attacked only by oleum, hydrofluoric acid or, more particularly, a hydrofluoric/nitric acid mixture. Fused alkalis will also attack it. In addition to these reagents, vanadium and niobium are attacked by other hot concentrated mineral acids but are resistant to fused alkali. 

The polymer manufacturing industry monitors extrac-tables in their products for a variety of purposes. These include not only additives but also mineral oils and waxes as well as incompletely polymerised dimers and trimers that have a pronounced effect in the finished product. Myer et al. [390] have compared... 

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