Year: 1897

page_text: I, ALFRED GEORGE WELLS, of No. 22, Billiter Street, in the City of London,
Gentleman, do hereby declare the nature of this invention to be as follows:-
The object of this invention is to provide a furnace for the more effective treat-
ment of ores.
For this purpose in order to prevent the admission of air to the chamber in
which the ore is treated by the gases used as the reducing agent, the furnace is
constructed in such a manner that the reducing chamber can be sealed by means
of a hood extending from each end of the roof of the chamber down into a water
channel situate at each end of the furnace. The ore is fed into the chamber at one
end of the furnace by means of an automatic hopper and is stirred up and con-
ducted along the floor of the reducing chamber by means of ploughs or rakes
attached transversely to two endless chains or wire ropes which pass over antifriction
rollers working in a water channel at each side of the chamber. On reaching the
end of the chamber the reduced ore falls into a hopper situate under the hood which
forms the water seal, the endless chains with the ploughs attached thereto passing
out of the chamber, under the hood, down into the water channel and around driving
wheels running therein. The chains and ploughs then pass up over the roof of the
furnace and around a pulley revolving in the water channel at the other end of the
furnace, up under the hood forming the water seal at that end and thence, in a
comparatively cool state, again into the reducing chamber.
The discharge hopper into which the ore falls after leaving the reducing chamber,
is provided at its upper part, with a shutter or door, to prevent the admission of
air to the reducing chamber whilst the hopper is being cleared.
The firing chamber is situate at the end of the furnace farthest from the feeding
hopper and the products of combustion pass through transverse flues under the floor
of the reducing chamber. Immediately below the floor of these transverse flues, air
flues are provided, which run in a longitudinal direction, from an opening at one
end of the furnace to the firing chamber at the other, which the air enters in a
highly heated state, over or through a trough of water placed beneath the fire grate,
thus utilising the waste heat from the bottom of the transverse flues. The admission
of air to the longitudinal flues can be regulated by a damper in the ordinary manner.
1007

page_text: I, ALFRED GEORGE WELLS, of 22, Billiter Street, also of 29, Cornhill, London,
Engineer, do hereby declare the nature of this invention and in what manner the
same is to be performed, to be particularly described and ascertained in and by the
following statement :-
This invention relates to improvements in apparatus for roasting and reducing ores
in a closed or air-tight chamber, and has reference both to an improved arrangement
and construction of furnace and flues for heating the chamber externally, and to an
improved arrangement and construction of the chamber within which the ore is
roasted by the heat imparted by the furnace and flues and is simultaneously reduced
by, the hot gases employed for such purpose; the improvements relating to the
furnace being designed to effect a better heating of the reducing chamber with a
more economical consumption of fuel; and those relating to the reducing chamber
being designed to enable the pulverized ore to be traversed therethrough by means
which will be in continuous operation within the chamber but will nevertheless pass
into and out thereof and will not be continuously subject to the action of the ore
reducing gases traversing the chamber, and which will consequently avoid the serious
disadvantages incidental to the present means of manipulating the ore while under
treatment in such apparatus, which means are either occasionally introduced by hand
through side openings into the chamber, the disadvantage of which is that air obtains
access to the chamber, which is not desired, or are arranged within the chamber and
continuously operate therein and are continuously subject to the action of the ore reduc-
ing agent within the chamber, the disadvantage of which is that they are so quickly
destroyed as to necessitate such frequent interruption of working and expense of
renewal as to render the treatment of ores in such apparatus impracticable and
commercially unsuccessful.
On the accompanying drawings ;
Figs. 1, represent a broken longitudinal section of the improved apparatus.
Fig. 2, represents a transverse section through A-B, Fig. 1;
Fig. 3, represents a top plan of the ore outlet end; and
Fig. 4, represents a sectional plan of the ore inlet end through C-D, Fig. 1.
In carrying out the invention, the reducing chamber, a, is built above a flue bed, b,
through which the furnace gases circulate from a fire chamber, 61, to a chimney, 66,
and the flue bed is built above an air heating bed, c, through which atmospheric air
traverses from an inlet at the end of the apparatus furthest from the fire chamber,
and, in doing so, is gradually heated up by the downwardly radiating heat of the
superposed flue bed, until it emerges in a highly heated condition into the fire
chamber, and so tends to economize the consumption of fuel.
The air heating bed is constructed with a transverse inlet duct, c¹, from which
branch a series of longitudinal ducts, c², which extend under the flue bed until they
emerge into a transverse duct, c³, at the fire chamber end of the apparatus, and,
which, by one or more descending ducts, ct, leads the hot air into the fire chamber, 61,
below the grate bars, 63. The inlet, c', is provided with an adjustable door, c, to
regulate the supply of air to the furnace.
The flue bed is constructed with a zig-zag flue, b', which leads from the fire
chamber, b¹, to and fro across the apparatus between the sub-posed air heating bed
and the super-posed reducing chamber, the transverse flues communicating at their
alternate ends with each other so as to make a continuous flue, which, at the further
end of the apparatus, emerges into the chimney, 65, by which the furnace gases are
carried off. The transverse flues, b', are provided with end doors, 6%, to facilitate
their cleaning. The fire chamber is also provided with an air tight door, b', to

page_text: prevent access of air to the fire chamber otherwise than through the air heating bed
ducts, excepting when desired.
The reducing chamber is built above the flue bed and may be made of any required
height, width and length, and is so adapted that the ore to be treated is automatically
supplied thereto at the cooler end of the chamber, and is automatically removed
therefrom at the hotter end, by means respectively serving when in operation to
prevent access of air to the chamber, and that the ore is traversed along from end
to end of the chamber by means which enter the chamber at one end and emerge
therefrom at the other end, and, at each end, dip into and pass through a water tank
by which the chamber end is closed air tight (both ends of the chamber being
similarly kept air tight) and the ore traversing means after emerging from the
chamber are cooled before re-entering the same. The chamber is also provided with
means by which the hot reducing gases are admitted thereinto at the ore exit end
and are led therefrom at the ore entry end either to the chimney by which the
furnace gases are led away or to any suitable condensing apparatus wherein such of
the products eliminated from the ore as are sufficiently valuable may be recovered as
bye-products, in any suitable manner.
The ore is automatically supplied to the chamber through a hopper, d, fitted with
a door, d', which is normally kept closed by a spring, 2, and is automatically opened
to discharge the contents of the hopper onto the hearth of the chamber, at any
required intervals, by travelling trippers, e¹, hereinafter further referred to.
The ore, after having been traversed along the chamber as hereinafter described,
falls into a discharge hopper from which it is automatically discharged into trucks
run thereunder without admitting air to the chamber. To this end the hopper is
made in upper and lower parts, f, f, the bottons of which are normally closed by
hinged counterweighted doors, f2, fs, respectively, having extending arms,*, adapted
to be alternately engaged at regular intervals by a stud, f, projecting from a rotating
part, f, so as to cause the upper hopper part to discharge the ore therein into the
lower hopper part while the outlet of the latter is closed, and the lower hopper part
to discharge its contents into the truck while the outlet from the upper hopper part
is closed.
The hopper door, f, may be played on by a fine spray of water from a pipe, 7, to
cool the hot ore which falls thereonto and prevent the door from buckling.
The ore is traversed from end to end of the reducing chamber by chains, e, fitted
with cross bars, e², carrying adjustable rakes e³, which are suspended just above the
bed of the chamber and serve to traverse the ore under treatment from the inlet to the
outlet end thereof. The bars, e², are supported at their ends by runners, et, guided
in channels, a², let into the side walls, a³, of the chamber and the intervening slack
portions of the chains, e, are supported by carrier wheels, a, arranged in other
channels, as, let into the chamber walls.
The channels, a², a³, are supplied by suitable inlets, a12, with running streams of
water which outflow at each end into a water tank, g, at the end of the chamber, the
water in the channels serving to aid in keeping cool the runners and carriers, e*, a*,
and the parts they respectively support while traversing the chamber.
At each end of the reducing chamber is arranged a water tank, g, into which there
dips a hood, a, which encloses the open ends of the chamber and of the channels, a², a³,
so as to seal the same from communication with the outer air. The chains, e, as
they enter the chamber and emerge therefrom, are guided by carrier wheels, a in
alignment with which and with the chain channels, a³, and so mounted as to partly
rotate under water in the tanks, g, are arranged other carrier wheels, g¹, which con-
junctively with the wheels, a', serve to deflect the portions of the chains respectively
leaving and re-entering the chamber and to cause the same together with the bars
and rakes they carry to pass under water, as represented in Fig. 1, whereby they
are cooled and prevented from being so highly heated while in the chamber as to be
rendered subject to the destructive action of the reducing gases circulating there-
through. The chamber roof, as, is provided with rails, a', which serve to support the

page_text: bars, e², and chains, e, while returning outside the chamber from the exit end to
the re-entering end thereof.
The trippers, e¹, by which the hopper door, ¹, is opened are carried by the chain
bars, 2, at any desired intervals apart to regulate the supply of ore as may be
required.
The side walls of the chamber are formed at suitable intervals with inspection
openings, a¹0, closed by air tight doors, a¹.
The reducing gases are caused to enter the chamber at the ore outlet end thereof
in a highly heated condition by pipes or ducts, h, leading from any convenient
heating or superheating apparatus wherein they are or may be generated or heated
to any desired degree, and, after coursing through the reducing chamber in a direction
opposite to the travel of the ore under treatment, they pass away from the chamber
by outlets, h¹, which may either lead to the chimney, 65, as represented, or may
lead to any suitable apparatus wherein they may be condensed and any contained
valuable matters recovered, as aforesaid.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is
In apparatus for roasting ores in a closed or air tight chamber :-
1. In combination; a closed reducing chamber; a flue bed; and an air heating
bed; the chamber hearth being built on the flue bed; the flue bed having trans-
versely arranged zig-zag flues serving to lead the furnace gases from the fire
chamber to the chimney to and fro under the chamber hearth; and the air
heating bed having longitudinally arranged ducts serving to lead atmospheric air
from an inlet at the cooler end of the apparatus to the fire chamber longitudinally
under the flue bed whereby it is heated, as set forth.
2. In combination; a reducing chamber adapted with means of automatically
supplying the ore to be treated and of automatically removing the treated ore and
to prevent access of air to the chamber and with means of admitting the ore
reducing gases to the chamber and leading them therefrom; a water tank at each
end of the chamber and a hood at each such end dipping into the water tank and
serving to seal and close the chamber end; and means of traversing the ore from
end to end of the chamber adapted to emerge from and to re-enter the chamber
through said water tanks and to be cooled thereby before re-entering the chamber,
as set forth.
DL
11
DOLL
1
J
11000
DAY, DAVIES, & HUNT,
Chartered Patent Agents, 321, High Holborn, London, W.C.,
Agents for the Applicant.