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Cement Mill
A cement mill (or finish mill in North American usage) is the equipment used to grind the hard, nodular clinker from the cement kiln into the fine grey powder that is cement. Most cement is currently ground in ball mills and also vertical roller mills which are more effective than ball mills. History Early hydraulic cements, such as those of James Parker, James Frost and Joseph Aspdin were relatively soft and readily ground by the primitive technology of the day, using flat millstones. The emergence of Portland cement in the 1840s made grinding considerably more difficult, because the clinker produced by the kiln is often as hard as the millstone material. Because of this, cement continued to be ground very coarsely (typically 20% over 100 μm particle diameter) until better grinding technology became available. Besides producing un-reactive cement with slow strength growth, this exacerbated the problem of unsoundness. This late, disruptive expansion is caused by hydratio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bassanite
Bassanite is a calcium sulfate mineral with formula CaSO4· H2O or 2CaSO4·H2O. In other words it has half a water molecule per CaSO4 unit, hence its synonym ''calcium sulfate hemihydrate''. Bassanite was first described in 1910 for an occurrence on Mount Vesuvius. It was named for Italian paleontologist Francesco Bassani (1853–1916). At Vesuvius it occurs as alterations from gypsum within leucite tephrite and as fumarole deposits. It occurs in dry lake beds in California and Australia. It also occurs interlayered with gypsum in caves. H. Schmidt and coinvestigators reported in 2011 that under dry conditions, the structure is monoclinic with space group ''C2'', but at 75% humidity, the structure is trigonal In crystallography, the hexagonal crystal family is one of the six crystal families, which includes two crystal systems (hexagonal and trigonal) and two lattice systems (hexagonal and rhombohedral). While commonly confused, the trigonal crystal ... with space group '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lignosulfonates
Lignosulfonates (LS) are water-soluble anionic polyelectrolyte polymers: they are byproducts from the production of wood pulp using sulfite pulping. Most delignification in sulfite pulping involves acidic cleavage of ether bonds, which connect many of the constituents of lignin. Sulfonated lignin (SL) refers to other forms of lignin by-product, such as those derived from the much more popular Kraft process, that have been processed to add sulfonic acid groups. The two have similar uses and are commonly confused with each other, with SL being much cheaper. LS and SL both appear as free-flowing powders; the former is light brown while the latter is dark brown. Lignosulfonates have very broad ranges of molecular mass (they are very polydisperse). A range of from 1,000 to 140,000 Da has been reported for softwood lignosulfonates with lower values reported for hardwoods. Sulfonated Kraft lignin tends to have smaller molecules at 2,000–3,000 Da. SL and LS are non-toxic, non-corrosiv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triethanolamine
Triethanolamine, or TEA is a viscous organic compound that is both a tertiary amine and a triol. A triol is a molecule with three alcohol groups. Approximately 150,000 tonnes were produced in 1999. It is a colourless compound although samples may appear yellow because of impurities. Production Triethanolamine is produced from the reaction of ethylene oxide with aqueous ammonia, also produced are ethanolamine and diethanolamine. The ratio of the products can be controlled by changing the stoichiometry of the reactants. : Applications Triethanolamine is used primarily in making surfactants, such as for emulsifier. It is a common ingredient in formulations used for both industrial and consumer products. The triethanolamine neutralizes fatty acids, adjusts and buffers the pH, and solubilizes oils and other ingredients that are not completely soluble in water. Triethanolammonium salts in some cases are more soluble than salts of alkali metals that might be used otherwise, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetic Acid
Acetic acid , systematically named ethanoic acid , is an acidic, colourless liquid and organic compound with the chemical formula (also written as , , or ). Vinegar is at least 4% acetic acid by volume, making acetic acid the main component of vinegar apart from water and other trace elements. Acetic acid is the second simplest carboxylic acid (after formic acid). It is an important chemical reagent and industrial chemical, used primarily in the production of cellulose acetate for photographic film, polyvinyl acetate for wood glue, and synthetic fibres and fabrics. In households, diluted acetic acid is often used in descaling agents. In the food industry, acetic acid is controlled by the food additive code E260 as an acidity regulator and as a condiment. In biochemistry, the acetyl group, derived from acetic acid, is fundamental to all forms of life. When bound to coenzyme A, it is central to the metabolism of carbohydrates and fats. The global demand for acetic aci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1,2-propanediol
Propylene glycol (IUPAC name: propane-1,2-diol) is a viscous, colorless liquid, which is nearly odorless but possesses a faintly sweet taste. Its chemical formula is CH3CH(OH)CH2OH. Containing two alcohol groups, it is classed as a diol. It is miscible with a broad range of solvents, including water, acetone, and chloroform. In general, glycols are non-irritating and have very low volatility. It is produced on a large scale primarily for the production of polymers. In the European Union, it has E-number E1520 for food applications. For cosmetics and pharmacology, the number is E490. Propylene glycol is also present in propylene glycol alginate, which is known as E405. Propylene glycol is a compound which is GRAS (generally recognized as safe) by the US Food and Drug Administration under 21 CFR x184.1666, and is also approved by the FDA for certain uses as an indirect food additive. Propylene glycol is approved and used as a vehicle for topical, oral, and some intravenous phar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ground Granulated Blast Furnace Slag
Ground-granulated blast-furnace slag (GGBS or GGBFS) is obtained by quenching molten iron slag (a by-product of iron and steel-making) from a blast furnace in water or steam, to produce a glassy, granular product that is then dried and ground into a fine powder. Ground-granulated blast furnace slag is a latent hydraulic binder forming calcium silicate hydrates (C-S-H) after contact with water. It is a strength-enhancing compound improving the durability of concrete. It is a component of metallurgic cement ( in the European norm ). Its main advantage is its slow release of hydration heat allowing to limit the temperature increase in massive concrete components and structures during cement setting and concrete curing, or to cast concrete during hot summer. Production and composition The chemical composition of a slag varies considerably depending on the composition of the raw materials in the iron production process. Silicate and aluminate impurities from the ore and coke are combi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metakaolin
Metakaolin is the anhydrous calcined form of the clay mineral kaolinite. Minerals that are rich in kaolinite are known as china clay or kaolin, traditionally used in the manufacture of porcelain. The particle size of metakaolin is smaller than cement particles, but not as fine as silica fume. Kaolinite sources The quality and reactivity of metakaolin is strongly dependent of the characteristics of the raw material used. Metakaolin can be produced from a variety of primary and secondary sources containing kaolinite: * High purity kaolin deposits * Kaolinite deposits or tropical soils of lower purity * Paper sludge waste (if containing kaolinite) * Oil sand tailings (if containing kaolinite) Forming metakaolin The T-O clay mineral kaolinite does not contain interlayer cations or interlayer water. The temperature of dehydroxylation depends on the structural layer stacking order. Disordered kaolinite dehydroxylates between 530 and 570 °C, ordered kaolinite between 570 a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silica Fume
Silica fume, also known as microsilica, (CAS number 69012-64-2, EINECS number 273-761-1) is an amorphous (non-crystalline) polymorph of silicon dioxide, silica. It is an ultrafine powder collected as a by-product of the silicon and ferrosilicon alloy production and consists of spherical particles with an average particle diameter of 150 nm. The main field of application is as pozzolanic material for high performance concrete. It is sometimes confused with fumed silica (also known as pyrogenic silica, CAS number 112945-52-5). However, the production process, particle characteristics and fields of application of fumed silica are all different from those of silica fume. History The first testing of silica fume in Portland-cement-based concretes was carried out in 1952. The biggest drawback to exploring the properties of silica fume was a lack of material with which to experiment. Early research used an expensive additive called fumed silica, an amorphous form of silica made ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
