The Salt Lake herald-Republican. [volume] (Salt Lake City, Utah) 1909-1918, 1910-05-07
PLAN TO EXPLOIT
AIR CONCENIRATOR
Local Interests About to Take
UD Kidder's Remarkable
Device.

Steps are being taken by local III
terests to incorporate a company to
exploit the Sandstone dry concentrat-
ing device, the invention Of George =.
kidder of this city. often has II Deeh
said of new devices that they were
likely to reVolutionize ere concentra-
ton. and il would seem that Mr. Kid
der's invention really promises 10 90
that. 1t employs an entirely new prln-
ciple and utilizes a new element Tor
the purpose-air instead Of water. 1t
would appear TO be as far ahead OF
wet concentration as the airSh1p or
the future promises to be ahead of the
sailboat
Natural laws Of air resistance and
gravity applied to the sizing OF ore
first crushed TO about 30-mesh-that
is the entire secret of Mr.. Kidder'
process. The rest is accomplished by
the operating of different combina-
lions of screens as the product may re-
guire 1t sounds far fetched to the I'M
initiated. but when it is demonstrated
it becomes as simple-wel. as simple
as the airship, and far more practical
than is the airship of today.
In the garnet of his home on Park
avenue. Mr.. Kidder has constructed a
crude machine which Is at once tbs
wonder and admiration of experienced
fea lure of it is in an air chamber
about twenty feet long. six feet high
ana eighteen inches wide, constructed
mainly Of building paper. At one end
of the air chamber is machinery
which comprises two belts, which are
operated lengthwise about four feet
In contact, and a hopper through
which the crushed ore is fed between
the rapidly revolving belts.
Air Does the Work.
Emerging from between the belts
the ore Is shot with considerable We
locity into the air chamber, and il is
there the atmospheric resistance gets
in its work together with gravity
The particles of ore which present the
least surface area, according to their
weight, go fdrthest, of course with
the result that the coarser gangue and
the heavier fines drop near the first
end of the chamber, while the coarseT
pieces of metal are projected TO the
farther end.
1t seems incredible. but the ore. is
scattered the full length of that cham
Der, with six and seven marked di-
visions of the product. The division
at the far end of the chamber, from
the feeding device, is 2 high-grade
concentrate; the division next TO that
is fair grade. while the one next to
the belts contains only gangue and q
Few fines. With screening of all bur
the two divisions of high-grade con-
centrates. Mr.. Kidder says that he ac-
complishes the remarkable high say
ing of 81 y per cent of the values
while extraction of S75S per cent OF
the values is accomplished by the
nfSt run, where air resistance and
gravity do the work.
Operating at relatively slow speed
these results are obtained with no cd.
pliances other than those indicated
For working with higher speed, how.
ever, is provided q system of fan.
Tor maintaining the atmospheric re
slstance IN the closed chamber.
MIR. Kidder contends, and his in.
Vention seems to prove. that not onl,
Is air much cheaper media for con
centration than is water but that If i
better; one reason being that fine mar
ucles precipitate more readily in ;
hShJ media than in a heavy one =,
also contends that his machine viii
De ABOUT so per cent more econoro
lcal than any other known separator
without considering the cost of 1varar