Steel produced by first refining it in a Bessemer converter and afterward
completing the process in an open-hearth furnace. Mersereau, 2
A combination of the duplex and the Talbot continuous process. Molten
steel from the Bessemer converter, already freed of its carbon, silicon,
and manganese contents, is charged into the Talbot furnace. As this molten
steel is poured through the oxidized slag, the phosphorus is removed
almost immediately. Sometimes pig iron is poured in afterwards, which
raises the carbon content of the bath and aids in its deoxidation. A
portion of the heat can usually be tapped about an hour after this
addition. Osborne
Two insulated-copper leading wires wrapped together with paraffined cotton
covering. Fay
The placing of alternate samples of coal or ore in different containers
that are then analyzed separately. Each container thus holds a
representative subsample taken at intervals throughout the sampling
intervals or period. Nelson
A heavy-liquid minerals separation process in which organic liquids of
high specific gravity, known as parting liquids, are used. With sp gr 1.00
to 2.96 and very low viscosities, they serve ideally for the medium in the
sink-and-float separation of solid materials. This process is used to
clean run-of-mine anthracite, refuse banks, or mixtures of the two. The
sizes of anthracite coal that can be cleaned are No. 1 buckwheat, and
larger. This includes sizes up through broken. See also:parting liquid
Mitchell
a. The capacity of a gem to withstand abrasion, impact, and chemical
alteration.
b. The rate of deterioration of foundry sand due to dehydration of its
contained clay.
The term was introduced by M.C. Stopes in 1919 to designate the
macroscopically recognizable dull bands in coals. Bands of durain are
characterized by their gray to brownish-black color and rough surface with
dull or faintly greasy luster; reflection is diffuse; they are markedly
less fissured than bands of vitrain, and generally show granular fracture.
In humic coals, durain occurs in bands up to many centimeters in
thickness. Widely distributed, but with exceptions not abundant.
CF:fusain; vitrain. See also:attritus; hards. IHCP
A monoclinic mineral, NaAl(AsO4 )F ; occurs with cassiterite at the
Barranca tin mine, Durango, Mexico.
A general term for a hard crust on the surface of, or layer in the upper
horizons of, a soil in a semiarid climate. It is formed by the
accumulation of soluble minerals deposited by mineral-bearing waters that
move upward by capillary action and evaporate during the dry season.
See also:ferricrete; silcrete; calcrete; caliche. Etymol: Latin durus,
hard, + crust. CF:hardpan
A process of electrodepositing hard chromium on the wearing surfaces of
parts as a protection against wear by friction. Osborne
a. Term for the microlithotype consisting principally of the following
groups of macerals: inertinite (micrinite, fusinite, semifusinite, and
sclerotinite) and exinite, particularly sporinite. Durite contains at
least 95% inertinite and exinite. The proportions of these two groups of
macerals may vary widely, but each must be greater than the proportions of
vitrinite and neither must exceed 95%. Durite E and durite I connote
durites rich in exinite and inertinite, respectively. It is found in many
coals, in fairly thick bands, principally in durains and the duller type
of clarain, generally common. IHCP
b. A coal microlithotype that contains a combination of inertinite and
exinite totalling at least 95%, and containing more of each than of
vitrinite. CF:durain
A rock-type coal consisting of the maceral vitrinite (telinite or
collinite) and large quantities of other macerals, mainly micrinite and
exinite. Micrinite is present in lesser quantities than is true with
clarodurain. CF:clarodurain
a. This term was introduced in 1956 by the Nomenclature Subcommittee of
the International Committee for Coal Petrology to designate the
microlithotype with maceral composition between those of clarite and
durite but closer to clarite than durite. Further specification is that
the proportion of vitrinite must exceed that of inertinite. It occurs in
fairly thick bands, and is widely distributed and, like clarodurite, is a
common constituent of most humic coals. The technological properties of
duroclarite are intermediate between those of clarite and durite, but
because of the predominance of vitrinite over inertinite they resemble
those of clarite more closely than those of durite. IHCP
b. Coal microlithotype intermediate between clarite and durite; vitrinite,
exinite, and inertinite each exceed 5% and the last is less abundant than
vitrinite. AGI
c. A coal microlithotype containing at least 5% each of vitrinite,
exinite, and inertinite, with more vitrinite than inertinite and exinite.
It is a variety of trimacerite, intermediate in composition between
clarite and durite, but closer to clarite. CF:clarodurite
Vitrain with minute inclusions of durain. CF:vitrodurain
A casting process that involves rigid attachment of the mold in an
inverted position above the crucible. The melt is poured by tilting the
entire assembly, causing the metal to flow along a connecting launder and
down the side of the mold. ASM, 1
A trigonal mineral, BaFe3 (AsO4 )2 (OH)5 ;
crandallite group; forms green to yellow-green rosettes or crusts.
See:ash
a. A device attached to the collar of a borehole to catch or collect dry,
dustlike rock particles produced in dry-drilling a borehole. CF:ducon
Long
b. Any device in which dust is collected or extracted from furnaces,
gases, etc.
a. An enclosed flue or chamber filled with deflectors, in which the
products of combustion from an ore-roasting furnace are passed, the
heavier and more valuable portion settling in the dust chamber and the
volatile portions passing out through the chimney or other escape.
Fay
b. Room air system, flue or dust extractor, where larger particles can
drop out of stream of gas and be periodically removed. Used in conjunction
with cyclones, electrostatic precipitators, and bag filters.
Pryor, 3
Coal or other dust particles carried in suspension in the air by currents
and eddies. Rice, 2