Improvements in and relating to Furnaces for the Treatment of Refractory and other Ores and Minerals, Animal and Vegetable Refuse or similar Material, and the Recovery therefrom of Bye- products.
Year: 1899

page_text: PROVISIONAL SPECIFICATION.
Improvements in and relating to Furnaces for the Treatment of
Refractory and other Ores and Minerals, Animal and Vegetable
Refuse or similar Material, and the Recovery therefrom of Bye-
products.
I, WILLIAM SMETHURST, of Brynmair, Dolgelly; North Wales, Engineer, do
hereby declare the nature of this invention to be as follows:-
This invention relates to improvements in furnaces for the treatment of
refractory and other ores and minerals by calcination or roasting and for the
recovery therefrom of sulphur arsenic antimony or other similar constituents
separated during the treatment, and also for the destruction of refuse such as
fish, fish offal, meat, town refuse, and all objectionable animal and vegetable
matter and to recover therefrom during the process of treatment such bye-
products as oil, fat, charcoal obtainable from such animal or vegetable material.
To carry my invention into effect I construct a furnace of tunnel formation
having a moving floor or hearth of refractory material carried upon trucks or
rollers or other equivalent means.
A self feeding hopper is arranged at one end of the furnace for delivering the
material to be treated upon the movable floor or hearth and a discharging device
is arranged at the other end.
The furnace is adapted to be heated by gaseous fuel injected into the furnace
through suitable orifices in the sides or roof. Provision is made for the proper
admixture of air with the gas to ensure perfect combustion.
Suitable compartments and exit passages from the furnace thereto are arranged
into which the various products are conducted when volatilized or disassociated
from the material being treated.
In this way the substance being treated is fed upon the moving floor or
hearth at one end of the furnace and by a slow continuous movement is passed
through the furnace up to the zone of high temperature and then away to the
delivery end.
During its transit through the furnace all the volatile matter and other
elements given off are drawn through the apertures provided for the purpose in
the chambers and tanks connected therewith and are there condensed.
The effluent gases are drawn or forced through water to purify them and thus
obviate the necessity of a chimney for carrying of noxious products.
By this means each element is driven off and collected at the point at which
it becomes volatile.
The form of furnace readily adapts itself for the provision of simple means
for charging and discharging automatically and continuously.
It is obvious that the furnace can be used for hardening and annealing manu
factured articles or as a glass or pottery furnace.
In the case of treatment of fatty matters provision is made for the draining
-

page_text: away and collection of the fat as it melts, so that is does not become destroyed
by burning.
Dated this 7th day of June 1800
:
FELL & JAMES,
1, Queen Victoria Street, London, E.C.,
Agents for the Applicant.
Improvements in and relating to Furnaces for the Treatment of
Refractory and other Ores and Minerals, Animal and Vegetable
Refuse or similar Material, and the Recovery therefrom of Bye-
products.
I, WILLIAM SMETHURST, of Brynmair, Dolgelly, North Wales, 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 follow-
ing statement:-
This invention relates to furnaces for the roasting of refractory ores or like
materials, but is especially applicable to the roasting of refractory auriferous
ores containing sulphur, antimony, and arsenic, and consists of a combination of
devices whereby the ore or like material may be cheaply travelled through the
furnace for a sufficient time to effect the volatilisation of certain substances,
such as sulphur, antimony, and arsenic, and of separating and collecting cham-
hers for the collection of these volatile substances as bye-products, thus reducing
the cost of treatment and rendering the ore immediately amenable to the most
ordinary and simple treatment by amalgamation for the recovery of the
precious metals therefrom.
And in order that my invention may be the better understood I will now pro-
ceed to describe the same with reference to the drawings hereto annexed and
to the letters and figures marked thereon.
Figure 1 is a perspective elevation of my complete furnace.
Figure 2 is a sectional plan of the same on the line Y Y of Figure 3 and
Figure 3 is a transverse section of the same on the line X X of Figure 2.
The roasting chamber of my furnace is in the form of a tunnel A, adapted to
be partially or wholly closed by doors B at either end. The hearth of the
furnace when in use is formed by trucks C travelling on an ordinary iron
track D laid right through the tunnel A. The frame of the trucks is covered
with layers of fire bricks E adapted to support the ore or other material to be
roasted and forming by close proximity to the sides of the tunnel and to one
another, and by enveloping a projecting course F of the side of the tunnel a
sufficient seal to the bottom of the furnace chamber without absolute contact
therewith.
The necessary heat for roasting the ore or like material on the trucks is
obtained through side orifices H in the walls of tunnel from tuyere or blow
pipes G connected to a main U supplied at the required pressure with such an
admixture of combustible gas such as producer gas and air as may be required
to produce either an oxidising or reducing blast.
Such holes H as are not required for admission of combustible gas may be
closed or left open to admit air if required.
The ore or like material on the truck hearths is reduced to a fairly uniform
stratum by passing under the adjustable door B, on entering, the said door
being set to skim off any surplus depth,
T

page_text: The ore or like material is thus travelled through the tunnel furnace A in
any desired period of time and all desired volatile constituents such as the
sulphur antimony and arsenic are there volatilized by roasting the charge in
such furnace varying from about 200° to 700° F.
Such volatile products are drawn by an aspirating fan K through an aperture
or apertures L in the roof of the furnace to a first collecting chamber M con-
veniently above the furnace which chamber has about 300° F. in temperature.
Here the least volatile constituents of the vaporized products such as the sulphur
condense, and may be collected, whilst the still volatile constituents such as
arsenic and antimony are drawn further on into a much larger condensing
chamber N through an aperture or apertures P in the dividing wall between the
chambers M and N and high up in such wall.
This chamber N is also provided with alternately placed baffle plates QQ
against which the passing vapours strike and by which condensation is increased.
The temperature of this chamber is little above that of the external atmo-
sphere and the antimony and arsenic may there be collected as oxides or sul-
phides as desired according to whether the gas supply to the furnace through
the tuyeres b is made a neutral or an oxidising blast as before described.
Suitable doors R R adapted to close gas-tight are provided in the chambers M N
by which access may be obtained for the collection of the condensed products
therein.
The aspirating fan K by its suction pipe S creates a sufficient draught or
suction to draw the volatile products in the direction desired in lieu of a chimney
and such final products of combustion or uncondensed gases as may pass through
it are finally discharged into or through a water tank T where noxious fumes
are finally condensed.
The value of the bye-products thus obtained by the roasting of arsenical or
antimonial sulphide ores covers to a great extent the cost of such roasting,
leaving the ores, if auriferous, excellently amenable to the ordinary and simple
forms of amalgamation or other known processes for the recovery of the precious
metals.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, I declare that what I claim
is:-
1st. In combination a tunnel furnace chamber: travelling hearths therein;
side apertures above said hearths for the admission of combustible gases and
air, and successive collecting chambers, connected in series to the tunnel fur-
nace, so that volatile gases from the latter traverse the whole length of each
chamber in succession, and an aspirating device drawing volatile products
through said collecting chambers and discharging uncondensed products into
water, substantially as described.
2nd. In combination, a tunnel furnace chamber; hearths mounted on truck
frames travelling therein on rail track; adjustable sliding doors to open furnace
ends; side apertures above said hearths; tuyeres or nozzles in part of them
for supply of combustible gases; a collecting chamber above said tunnel fur-
nace connecting at one end to said tunnel furnace; a second collecting chamber
adjacent to first collecting chamber connecting with latter at end farthest from
furnace connection; baffle partitions in second collecting chamber; an aspirat-
ing fan connected to latter chamber at end farthest from entry; and a water
tank for reception of the discharge from said fan, substantially as described.
Dated this 7th day of April 1900.
FELL & JAMES,
1, Queen Victoria Street, London, E.C.,
Agents for the Applicant.