Juniata sentinel and Republican. [volume] (Mifflintown, Juniata County, Pa.) 1873-1955, 1895-09-25
MINERAL WOOL
Tow Produced from Matter that was
Formerly Wasted.

MINERAL WOOL
l0ow Produced from Matter that Wa
Formerly Wasted.
Since the discovery. some years ago
that asbestos could be felted togethe
into a sort of paper and used whereve
nonconducting, non-combustible pack
ing was needed, the demand for it ha
steadily increased. New forms ant
new uses are continually appearing
while the supply is constantly diminish
ing. This has led to the search for
substitute.
By melting together the various min
erals Of which asbestos Is composed
material Of the same composition Il
easily obtained, but the stringy
fbrous quality which makes the as
bestOs so valuable Is wanting. An &C
cidental blast of steam against stream
of melted Stag from an iron furnac'
gave the first and most important steI
In the solution Of the problem, and from
this 1t has been worked out almost t.
perfection. At first "glass," or min
eral" wool was made largely from Stag
which contains many Of the minerals
needed-sand. lime and iron. But this
product was too CLASSY, was not touSr
enough and melted too easily.
A careful analysis Of asbestos was
made, and the minerals, limestone, sand
fire-clay or kaolin and iron Stag. con
tanning the proper elements, were
'"'xed.
As made now, by the improved meth
ods. waste products from other fac
tories are used principally. Broken
glass from windows and from bottle
houses furnishes the sand and part
of the lime; pieces of fire-clay bricks
broken glass-pots and dishware thai
has warped or cracked In the kilns fur
nish the clay, and iron Stag from the
pudding ovens supplies the iron and
part of the sand and lime. A little ex
ira limestone is also added. These
waste products, besides being cheaper
are better than simple sand, lime and
clay would be, as they are in hard
,hunky form, and "stand up" In the
furnace, allowing better circulation
of air and gas while heating. Loose
sand and clay would pack.
The materials are crushed and mixed
according to n rough formula, which
is worked out by experiment. 1t Is
very necessary that the amount of each
should be just right. If too much glass
is used the wool Is brittle and harsh; II
too much clay, the fibers are coarse
and heavy, and II too much Iron, the
product is dark and does not sell we'll
The mixed material Is placed In tall
fire brick furnaces. with alternate lay
ers of coke, each layer being about one
foot deep. Natural gas, where obtain
able, is led into the bottom Of the fur
mace. the fire is lighted and blast OF
mir from blower Is turned on. getting
up an intense heat. The glass melts
acting rs n flux and melting the other
materials. The part nearest the bot
tom Of the furnace melts first and the
whole mass settles down.
When the bottom is sufficiently liquid
a small hole is opened at the side OF the
furnace and the fluid mass is allowed to
flow out in stream one inch In diam
eter. AS this falls Jet Of steam from
two fiat, fan shaped nozzles is directed
against 1t. blowing 1t into q fine spray,
which, on cooling, Is n white, fibrous
mass resembling fine, well-washed
wool, hence its name
The spray is blown through a small
window into n large collecting room.
While the blast Is on this room is
filed with n white cloud looking like
cotton down. Two furnaces and two
rooms are used. alternating with each
other When the blast Is finished In one
furnace the downy wool is allowed to
settle and is then scraped from the sides.
the floor and the ceiling; 1t is weighed,
packed in bales and then Is ready for
the market
The heaviest part, which settles near
est the windows, contains little, bead
like bodies. called in the trade "shOt"
and due to imperfect blowing. This wool
is remelted or sold for rough packing.
The uses of the mineral wool are very
numerous and are multiplying all the
time. The chief ones are the adultera-
ton Of asbestos; packings to retain
heat, as on steam pipes, steam cylinders
and boilers; packings to keep out heat
in Ice machines, refrigerators, cold
rooms and cold storage warehouses. OF
late large amounts are used for deaden-
Ing of walls and floors in fireproof build.
ings
The mineral wool Is used either loose
or in the form of paper, felting or thick
wadding.