IMPROVEMENTS IN PULVERISING AND TREATING PROVISIONAL SPECIFICATION
Year: 1883

page_text: LETTERS PATENT to Alexander James Struthers of Glasgow in the County of
Lanark for an Invention of "IMPROVEMENTS IN PULVERISING AND TREATING
PROVISIONAL SPECIFICATION left by the said Alexander James Struthers
at the Office of the Commissioners of Patents on the 22nd March 1883.
ALEXANDER JAMES STRUTHERS, of Glasgow, in the county of Lanark,
"IMPROVEMENTS IN PULVERISING AND TREATING DIAMONDIFEROUS ORE, AND IN
APPARATUS THEREFORE,"
This Invention relates to improvements upon, or developments of, the Invention
for which Letters Patent were granted to the present applicant, and dated
23rd September 1881 (N° 4,104).
In the Specification of the Letters Patent referred to, was described a mode of
treating diamondiferous ore by the action on it of steam, hot water, or acid, to
soften and facilitate the pulverising of the material which was carried on an endless
band, through a close vessel.
According to the present Invention the method of treating the ore is modified,
and the apparatus in which the ore is treated and in which it is pulverised is
simplified in construction.
Instead of subjecting the diamond ore to the action of steam or hot water alone,
the ore is acted on by heated air, or by the hot products of combustion of a
furnace, either alone, or in combination with the use of water or steam. In one.
arrangement of the apparatus in which the ore is treated, and which is designed to
utilise the construction of machine described in the specification of Letters Patent
N° 4,104 of 1881, the ore is partially broken up by means of crushing rolls and
delivered into a separate close vessel or tank through which heated air or the hot
products of combustion of a furnace is or are caused to circulate.
From this separate vessel the heated ore is fed or allowed to fall through a
suitable trap door or outlet, into the hopper of the steaming tank or vessel forming
part of the apparatus described in the specification of Letters Patent referred to;

page_text: and in this tank or vessel the heated ore is subjected to the action of steam or hot
water while being conveyed to the disintegrating apparatus. It is advantageous
in practice that the process of treating the ore to soften it, and of pulverising the
softened mass, should be effected in a continuous operation and within a single
vessel, and it is therefore preferred to modify that portion of the apparatus in
which the steaming or moistening of the ore formerly took place, so that the ore
may be therein subjected to the combined action of heated air or gases, and steam
or water.
For this purpose the tank or vessel through which the ore is carried, is divided
longitudinally by a horizontal partition, and an endless carrying band is fitted
in each compartment. The ore, entering the upper compartment of the tank
or vessel is conveyed in one direction by the upper band, drops through a doorway
or opening in the dividing partition, on to the lower band which conveys it in the
opposite direction towards the disintegrating apparatus by which the ore is
broken up.
Continuous rotating screws fitted within long close tubular vessels may be
substituted for the carrying bands. Through one of the compartments, heated air
or furnace gases are circulated, and into the other, steam or water is admitted.
In this arrangement it is most convenient to admit the air or gases to the upper
compartment, and thereby subject the ore first to heat and afterwards to the
penetrating moistening action of steam or water. The order of treatment may
however be reversed with equal or nearly equal advantage, provided that the
arrangement of the vessel, through which the ore passes, be suitably modified.
In a modified arrangement of the improved apparatus, the carrying bands or
rotating screws within the heating and steaming chambers are altogether dispensed
with, and there is combined with the disintegrating apparatus described in the
Specification of Letters Patent referred to, or with the improved disintegrating
- apparatus hereinafter described, a close vessel or vessels made in the form of a
vertical or inclined funnel, or cupola, or tower, into which the ore is fed at the top
through a suitable hopper or similar device, and descends by gravity. At about
the mid length vertically of the vessel, a tube or a number of tubes enter the sides
of the vessel, and through these tubes steam or water spray enters or is injected.
At the lower end of the vessel a large inlet pipe or pipes are fitted, through which
heated air, which has previously been heated by any suitable furnace, or the hot
products of combustion of a furnace enter and circulate among the lumps or pieces
of ore. The bottom of the ore bolding vessel may be enclosed, and suitable doors are
formed either in the side or in the bottom, through which the moistened and
heated ore passes, and is fed directly into the disintegrating apparatus referred to.
The feeding in of the ore to the holding vessel is continuously carried on, and the
outlet is also continuous, and both may be regulated by suitable means. The ore
in its descent through the vessel is acted on by the steam or water, and by the
heated air or gases, and finally emerges at the bottom in a softened state in which
it is readily broken up by the disintegrating apparatus. In this arrangement of
apparatus, the inlet for the steam or water may be conveniently placed at the
bottom of the vessel, while the inlet for the heated air or gases may be placed at a
higher level, or both may enter at the same level. When water is used to moisten
the hard ore, the ore may be passed through water or be watered, before entering
the ore-holding vessel in which heated air or hot gases only will be caused to
circulate...
In a modified arrangement however the water may be allowed to trickle
through a perforated plate over or near the top of the vessel to moisten the
descending ore, while the heated air or hot gases ascend through it. In many
cases the ore is sufficiently, damp as it comes from the nine, in which case heated
air or hot gases are alone admitted to the vessel containing the ore.
When the hot products of combustion of a furnace are caused to ascend through
the moistened ore the disintegration of the ore inay be facilitated by chemical
action. For example, if the shale which is usually found in the neighbourhood of

page_text: diamond mines be used as fuel in the furnace from which the products of com-
bustion are supplied to heat the ore in the holding vessel, the gaseous sulphurous
acid and fumes from the furnace will be partially absorbed by the water used to
moisten the ore, and the water will become acidulated. The acidulated water
acting on the calcareous matter which binds together the mass of the ore. will
decompose such matter and loosen or disintegrate the mass.
The holding vessel in which the ore is treated may be made cylindrical; and be
caused to rotate on its axis, which, in such a case will be most conveniently
inclined. The vessel may be in the form of a long boiler shell, and may be fitted
with driving gear and be arranged to revolve on antifriction rollers.
The rotation of the vessel is intended to provide thorough circulation of the
heated air or gases, and steam or water through the ore, and by rubbing together of
the lumps to facilitate the breaking or pulverising of the ore.
The ore is or may be led from the heating and moistening vessel or chamber to
the disintegrating apparatus through a stationary or vibrating or revolving screen
or riddle by means of which a large proportion of the broken mass may bo
separated from the larger stones and pieces which would pass over the screen or
riddle into the disintegrator. The broken ore passing through the screen may
then be led by screws or bands or other means direct to the crushing rolls of the
disintegrating apparatus, or to separate crushing rolls. By this means the work of
breaking up the ore by the revolving wheel or drum of the-disintegrating apparatus
may be considerably reduced.
:
The disintegrating apparatus to which the heated, moist, and softened ore is
fed, resembles in its general features the disintegrating apparatus described in the
specification of Letters Patent N° 4104 of 1881. The elevator, by which the
broken material was raised. from the disintegrating wheel to the sifting screen or
grating, is dispensed with, and the screen or grating is lowered and has a
vibrating motion imparted to it for the purpose of shaking through the broken.
ore and distributing it evenly between the pulverising rolls which are fitted
beneath. An elevator is fitted in connection with the disintegrating and
pulverising machine to raise the pulverised ore and deliver it into the ordinary
washing machine or machines used for separating or sifting out the diamonds.
The object of introducing this elevator is that the ore as it comes from the mine
may pass into the heating and steaming tank or vessel, be therein moistened and
softened, thence pass into the disintegrating and pulverising apparatus, be therein
pulverised, and thence be delivered into the washing machine, in one continuous
operation during which there is no opportunity given for handling the ore and
abstracting the diamonds.
The improved mode of treating the ore by subjecting it to the combined action
of heated air or gases, and steam or moisture as herein described may be carried on'
independently of the disintegrating apparatus, and the ore after treatment within
the close vessel or vessels described may be pulverised and the diamonds
separated by hand labour and by washing machines in the usual way.

page_text: "
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Alexander James,Struthers in the Great Seal Patent Office on the
21st September 1883.
ALEXANDER JAMES STRUTHERS, of Glasgow, in the County of Lanark
"IMPROVEMENTS IN PULVERISING AND TREATING DIAMONDIFEROUS ORE, AND IN
APPARATUS THEREFOR
"
My said Invention relates to improvements upon, or developments of, the
Invention for which Letters Patent were granted to me, and dated 23rd September
1881 (N° 4,104).
In the Specification of the Letters Patent referred to, there was described a mode
of treating diamondiferous ore by the action on it of, steam, hot water or-acid, to
soften and facilitate the pulverising of the material which was carried on an
endless band through a close vessel.
According to the present Invention, the method of treating the ore is modified,
and the apparatus in which the ore is treated and in which it is pulverised is
simplified in construction.
Instead of subjecting the diamond ore to the action of steam or hot water
alone, the ore is acted on by heated air, or by the hot products of combustion
of a furnace, either alone or in combination with the use of water or steam.
Various modifications of apparatus used in carrying out the Invention are
illustrated in the accompanying Drawings. Figure 1 shows one arrangement of
the apparatus in which the ore is treated and which is designed to utilise the
construction of machine described in the Specification of Letters Patent N° 4104
of 1881. In this apparatus the ore is partially broken up by means of crushing
rolls A A, and delivered into a separate close vessel or tank B through which
heated air or the hot products of combustion of a furnace C is or are caused to
circulate. The furnace C is conveniently placed under the vessel B and may serve
partially to support it. The hot furnace gases pass by a flue C' into an annular
space B' surrounding the vessel B, and are discharged among the broken ore within
the vessel through openings formed at intervals apart. The ascent of the gases
through the ore may be facilitated by forced combustion in the furnace, or by.
injecting the gases into the furnace by a steam jet, or by other means.
The upper
end of the vessel B is open to allow of the free escape of the furnace gases after
they have imparted their heat to the broken ore. If the ore is fresh from the
mine, the effect of the heat is to cause expansion of the water or moisture
.combined with the ore, and to cause it to crumble down. From the vessel B, the
heated ore is fed by a roller D or allowed to fall through a suitable trap door or
outlet, into the steaming tank or vessel E forming part of the apparatus described
in the Specification of Letters Patent referred to; and in this tank or vessel the
heated ore is subjected to the action of steam or hot water while being conveyed
by the band F to the disintegrating apparatus G, screen H, and crushing rolls I
which are substantially the same as are described in the former specification.
It is advantageous in practice that the process of treating the ore to soften it,
and of pulverising the softened mass should be effected in a continuous operation
and within a single vessel and it is therefore preferred, in some cases, to modify
that portion of the apparatus in which the steaming or moistening of the ore
formerly took place, so that the ore may be therein subjected to the combined
action of heated air or gases and steam or water.
For this purpose the tank or vessel E through which the ore is carried, is divided
longitudinally by a horizontal partition and an endless carrying band is fitted in

page_text: each compartment, or in lieu of the band inclined movable boards are used which
divide the vessel into compartments. Figure 2 illustrates this arrangement of the
apparatus. The ore entering the upper compartment of the tank or vessel through
the hopper or rollers A is conveyed in one direction by the upper band, or on the
upper board J, drops through a doorway or opening in the dividing partition, or is
fed by a rotating hopper j on to the lower band or board J' which conveyes it in
the opposite direction towards the disintegrating apparatus G by which the ore is
broken up.
Continuous rotating screws fitted within long close tubular vessels
may be substituted for the carrying bands or boards. Through one of the
compartments thus formed, heated air or furnace gases are circulated, and into the
other steam or water is admitted. In this arrangement it is most convenient to
admit the air or gases to the upper compartment, and thereby subject the ore first
to dry heat, and afterwards to the penetrating moistening action of steam or water.
The order of treatment may however be reversed with equal or nearly equal
advantage, provided that the arrangement of the vessel through which the ore
passes be suitably modified.
In a modified arrangement of the improved apparatus illustrated in figure 3, the
carrying bands or boards or rotating screws within the heating and steaming
chambers are altogether dispensed with; and there is combined with the disin-
tegrating apparatus described in the specification of Letters Patent referred to, or
with the improved disintegrating apparatus hereinafter described, a close vessel.or
vessels made in the form of a vertical or inclined funnel, cupola, or tower B, into
which the ore is fed at the top through a suitable hopper or similar device fitted
with breaking rolls A, and through which it descends by gravity. At about the
mid-length vertically of the vessel, a tube or a number of tubes connected by an
annular space B2 enter the sides of the vessel, and through these tubes steam or
water spray enters or is injected. At the lower end of the vessel, a large inlet
pipe or pipes similarly connected by an annular space B' are fitted, through which
heated air (which has previously been beated by any suitable furnace) or the hot
products of combustion of a furnace, enter and circulate among the lumps or pieces
of ore.
The bottom of the ore holding vessel may be enclosed, and suitable doors
are formed either in the side or in the bottom, or the vessel is fitted with a suitable
feeding roller D, by which the moistened and heated ore passes, and is fed directly
into the disintegrating apparatus.. The feeding in of the ore to the holding vessel
is continuously carried on, and the outlet is also continuous, and both may be
regulated by suitable means.
The ore in its descent through the vessel B is acted on by the steam or water, and
by the heated air or gases and finally emerges at the bottom in a softened state in
which it is readily broken up by the disintegrating apparatus. This apparatus
comprises a disintegrating wheel or roller G which breakes up the ore, a vibrating
screen or riddle H by which the larger unbroken pieces of ore are separated and
retained, and a pair of elastic rolls I, I, between which the softened ore passing
through the screen is finally pulverised. From these rolls the soft mass may fall
or be carried up into the washing machine, according as this machine is fitted at a
lower or higher level. The condensed steam mixes with the pulverised ore to form
a pasty mass from which the diamonds or other stones are readily separated in the
ordinary ore washing machine. In this arrangement of apparatus, the inlet B¹ for
the steam or water may be conveniently placed at the bottom of the vessel, while
the inlet B³ for the heated air or gases may be placed at a higher level, or both
may enter at the same level as is indicated in figure 4. In this case the hot air or
hot furnace gases are injected by a steam jet k which is combined with the hot air
or gas inlet pipe C', and forms a species of hot air injector.
When water is used to moisten the hard ore, the ore may be passed through
water, or be watered, before entering the ore-holding vessel B in which heated air
or hot gases only will be caused to circulate. The modification of apparatus shown
in figure 4 is suitably arranged for this purpose.
10
Water is allowed to trickle through a perforated plate or rose. L.fitted over. or.

page_text: '
near the top of the vessel B to moisten the descending ore, while the heated air or
hot gases injected from the flue C₁ ascend through it. In many cases the ore is
sufficiently damp as it comes from the mine, in which case heated air or hot gases
are alone admitted to the vessel containing the ore, and the rose L is dispensed
with, or the supply of water is shut off. Instead of the disintegrating wheel, a
pair of toothed or fluted rollers G revolving rapidly may be fitted at the lower end
of the vessel B to break up the softened ore-This modification is shown in
figure 5.
When the hot products of combustion of a furnace are caused to ascend through
the moistened ore, the disintegration of the ore may be facilitated by chemical
action. For example, if the shale which is usually found in the neighbourhood of
diamond mines be used as fuel, or be mixed with the fuel used in the furnace from
which the products of combustion are supplied to heat the ore in the holding
vessel, the gaseous sulphurous acid and fumes from the furnace will be partially
oxidised by the action of the air and steam admitted and will be absorbed by the
water used to moisten the ore, and the water will become acidulated or mixed with
sulphuric acid. The acidulated water acting on the calcareous matter which binds
together the mass of the ore will decompose such matter and loosen or disintegrate
the mass.
The holding vessel in which the ore is treated may be made cylindrical and
caused to rotate on its axis, which in such a case will be most conveniently inclined.
Figure 6 illustrates this modification of apparatus. The vessel B is made in the
form of a long boiler shell, and is fitted with worm gear M by which it is driven,
and it is arranged to revolve on anti-friction rollers Ñ. The hot air or the hot
gases either alone or combined with steam, are led in at one end and after
traversing the vessel and acting on the ore within it, they escape at the opposite
end by a flue-pipe C².
The ore
The rotation of the vessel is intended to provide thorough circulation of the
heated air or gases and the steam or water through the ore, and by rubbing
together of the lumps to facilitate the breaking or pulverising of the ore.
is fed in to the vessel B by a stationary hopper fitted with breaking rolls A, and it
passes out in a softened state directly on to the disintegrating apparatus G, H, I,
which is similar to that already described. The necessary power for rotating the
vessel is obtained through gearing from an engine which is shown in proximity to
the machine.
To avoid the expenditure of power required to rotate the vessel, the cylindrical
inclined vessel B may be made stationary as is indicated in figure 7.
The ore is or may be led from the heating and moistening vessel or chamber B to
the disintegrating apparatus through a stationary or vibrating or revolving screen
or riddle, by means of which a large proportion of the broken mass may be
separated from the larger stones and pieces which would pass over the screen or
riddle into the disintegrator. The broken ore passing through the screen may then
be led by screws or bands or other means direct to the crushing rolls of the
disintegrating apparatus, or to separate crushing rolls. By this means the work of
breaking up the ore by the revolving wheel or drum of the disintegrating apparatus
may be considerably reduced. In the machine shown in figure 7 an arrangement
of this kind is provided. A screen O is fitted near the lower end of the vessel B
and up through it work the teeth of a revolving rake or roller P, which also serves
to feed the lumps of ore to the disintegrator. The smaller pieces of the ore fall
through the screen on to a shoot Q which guides the material in between a pair of
elastic crushing rolls. I¹ similar to the main crushing rolls I.. The crushed mass
falls thence on to a band. R which conveys it to a point where it mingles with the
mass of material from the main crushing rolls I, and where it falls over a shoot S
into the diamond washing or separating machine T.
The disintegrating apparatus to which the heated, moist, and softened ore is fed,
by the various machines described, resembles in its general features the disinte-
grating apparatus described in the specification of Letters Patent N° 4104 of 1881.

page_text: The elevator by which the broken material was raised from the disintegrating
wheel to the sifting screen or grating, is dispensed with, and the screen or grating
is lowered and has a vibrating motion imported to it for the purpose of shaking
through the broken ore and distributing it evenly between the pulverising rolls
which are fitted beneath. When the apparatus cannot be conveniently fitted to
discharge the pulverised ore direct into the washing machine, an elevator is fitted
in connection with the disintegrating and pulverising machine to raise the
pulverised ore and deliver it into the ordinary washing machine or machines used
for separating or sifting out the diamonds. The object of introducing this
elevator is that the ore as it comes from the mine may pass into the heating and
steaming tank or vessel, be therein moistened and softened, thence pass into the
disintegrating and pulverising apparatus, be therein pulverised, and thence be
delivered into the washing machine, in one continuous operation, during which
there is no opportunity given for handling the ore and abstracting the diamonds.
The improved mode of treating the ore by subjecting it to the combined action
of heated air or gases, and steam or moisture as herein described may be carried on
independently of the disintegrating apparatus, and the ore after treatment within
the close vessel or vessels described may be pulverised and the diamonds separated
by hand labour and by washing machines in the usual way.
Having now particularly described the nature of my said Invention, and in what
manner the same is to be performed, I declare that what I claim is,―
First. The process or mode of treating diamondiferous ore, which consists in
subjecting the ore within a suitable vessel to the combined 'action of hot air or
hot furnace gases and steam or moisture, substantially as and for the purpose set
forth.
•
Second. The improved mode of pulverising diamondiferous ore, which consists in
first softening the broken ore by passing it through a vessel in which it is subjected
to the combined action of hot air or furnace gases and steam or moisture and then
passing the softened mass through disintegrating and crushing apparatus, substan-
tially as herein set forth.
Third, The various arrangements of vessels and apparatus herein described
and illustrated for treating and pulverising diamondiferous ore in a continuous
Imanner.
Fourth. The combination with the apparatus described for disintegrating,
screening and crushing diamondiferous ore, of a stationary or rotating vessel
supplying the ore thereto, such vessel being adapted for treating the ore by the
combined action of hot air or furnace gases and steam or moisture, substantially
as herein described and illustrated.
In Witness Whereof, I the said Alexander James Struthers, have hereunto set
my hand and seal this Eighteenth day of September, in the year of our Lord One
thousand eight hundred and eighty three.
Witness
WALLACE FAIRWEATHER C.E.
Fel. Inst. Patent Agents
Glasgow.
AJ STRUTHERS. (L.S.)