Fly ash
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Fly ash (also known as a coal combustion product, or CCP) is the finely divided mineral residue resulting from the combustion of powdered coal in electric generating plants. It is also called pulverized fuel ash. Fly ash consists of inorganic, incombustible matter present in the coal that has been fused during combustion into a glassy, amorphous structure. Coal can range in ash
content from 2%-30%, and of this around 85% becomes fly ash. (The remaining 15% is called bottom ash and isn’t lifted up by the flue gases.)

Fly ash material is solidified while suspended in the exhaust gases and is collected by electrostatic precipitators or filter bags. Since the particles solidify while suspended in the exhaust gases, fly ash particles are generally spherical in shape and range in size from 0.5 µm to 100 µm. They consist mostly of silicon dioxide (SiO2), aluminium oxide (Al2O3) and iron oxide (Fe2O3), and are hence a suitable source of aluminum and silicon for geopolymers. They are also pozzolanic in nature and react with calcium hydroxide and alkali to form cementitious compounds. Fly ash also contains some heavy metals.

http://www.aic.info.ro/sit/dictio1?csc=cenusa zburatoare
Termen Definitie
cenusa zburatoare Reziduu de ardere a combustibililor solizi, care este antrenata in plan vertical prin fenomenul de convectie. Unele cenusi zburatoare pot contine compusi de siliciu cu o comportare de liant slab hidraulic. Acesti compusi recomanda utilizarea lor alaturi de ciment pentru prepararea betonului

Bottom ash
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"Bottom ash" refers to the non combustible constituents of coal with traces of combustibles embedded in forming clinkers and sticking to hot side walls of furnace during the furnace working. The clinkers fall by themselves into the water or sometimes by poking manually, and get cooled.

The clinker lumps get crushed to small sizes by clinker grinders mounted under water and fall down into a trough from where a water ejector takes them out to a sump. From there it is pumped out by suitable rotary pumps to dumping yard far away. In another arrangement a continuous link chain scrapes out the clinkers from under water and feeds them to clinker grinders outside the bottom ash hopper.

Bottom ash may be used as an aggregate in road construction and concrete, where it is known as furnace bottom ash (FBA), to distinguish it from incinerator bottom ash (IBA), the non-combustible elements remaining after incineration. It was also used in the making of the concrete blocks used to construct many high-rise flats in London in the 1960s

cu un ajutor din grandictionnaire
omaine(s) : - industrie papetière


anglais
français

bottom ash
cendres de grille n. f. pl.


Définition :
Particles collected in the ash pan of combustors, with or without auxiliary fuel, wood residue, bleach waste or sludge from wastewater treatment of pulp and paper mills that can be separated or combined with fly ash.


Sous-entrée(s) :
synonyme(s)
grate ash

ZGÚRĂ, zguri, s.f. 1. Partea minerală fuzibilă din cenuşa cărbunilor, care se aglomerează în procesul de solidificare. ♦ Funingine. 2. Reziduu rezultat în procesul de extragere a metalelor din minereuri sau la topirea metalelor, constituit din oxizi formaţi în procesul tehnologic, din silicaţi, pământ etc. ♦ Strat de oxizi metalici format deasupra unei suduri executate cu arc electric. 3. Cenuşă întărită (provenită din lucruri arse). – Cf. alb. z g j y r ë, bg. z g u r i j a.



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Note added at 18 hrs (2007-02-20 16:50:59 GMT)
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daca nu-ti inspira incredere
"zgura"
poti sa-i zici
cenusa depusa/solidifiata pe peretii boilerului