IMPROVE- MENTS IN THE PROCESS AND APPARATUS FOR SEPARATING TIN FROM SCRAP OR WASTE METAL
Year: 1882

page_text: LETTERS PATENT to Charles Denton Abel of No 28 Southampton Buildings
Chancery Lane in the County of Middlesex for an Invention of IMPROVE-
MENTS IN THE PROCESS AND APPARATUS FOR SEPARATING TIN FROM SCRAP
OR WASTE METAL Communicated to him from abroad by Friedrich Albert.
Reinecken and Ludolf Poensgen both of Düsseldorf in the German Empire.
PROVISIONAL SPECIFICATION left by the said Charles Denton Abel at.
the Office of the Commissioners of Patents on the 15th September 1882.
دو
CHARLES DENTON ABEL of No. 28 Southampton Buildings, Chancery Lane, in the
County of Middlesex "IMPROVEMENTS IN THE PROCESS AND APPARATUS FOR
SEPARATING TIN FROM SCRAP OR WASTE METAL [Communicated to him from
abroad by Friedrich Albert Reinecken and Ludolf Poensgen both of Düsseldorf in
the German Empire.]
According to the present invention the separation of tin from scrap or waste
metal is effected by means of a liquid which dissolves the tin, and by means of a
series of revolving drums through which the metal is made to pass consecutively
and automatically, whereby labor is economised and a very perfect removal of
the tin insured.
The liquid employed for this purpose is a lye consisting of hydrate of soda or
potash dissolved in water to which oxide of lead (Massicot) has been added to
excess.
This lye is placed in a series of vats or receptacles in each of which is a
cylindrical drum revolving on a horizontal axis and immersed to about half its
diameter. The vats are heated so as to maintain the lye at about boiling point
either by external fire heat or steam jackets or by internal steam pipes.
The drums have large central openings in their sides; they are supported on
their shafts by internal radial arms situated at one side thereof so as to leave the
other side quite frée. The arms have inclined branches at their ends, leading
towards the free side, which is connected thereto by bolts passing through slotted

page_text: holes so that the side can be shifted round somewhat. A series of bars placed close
together in a radial direction are passed loosely through holes in the adjustable
side and in the opposite arms, which bars constitute grate like scoops or blades by
which the scrap metal in the drum is raised up as the drum revolves. In addition
to these bars plates are provided which may be inserted behind the bars when it
is desired to accelerate the delivery of the scrap metal from the drum, such delivery
being also regulated by shifting the movable side of the drum so as to cause the
bars to assume a more or less oblique position. A series of these drums are
arranged side by side and between each two is an inclined shoot connected to the
fixed framing and having at its upper end a hinged flap so arranged as in one
position to project obliquely into the interior of the drum and catch the scrap
metal carried up by the scoops and convey the same down the shoot into the next
drum. When turned up on its hinge, the flap prevents the delivery of the metal
into the shoot.
.
As the drum revolves in the lye of the vat a chemical reaction takes place
between the lye and the tin on the scrap metal, the latter becoming dissolved by
the former while lead is deposited from the lye in the form of mud in the drum
and the vat. As a portion of this mud is also deposited on the scrap metal, it is
advisable to place together with the same a quantity of granular metal in the
drum, which, as the latter revolves, has a scouring effect on the scrap metal. The
mud that is deposited in the vat is automatically removed therefrom by hinged
scrapers on the outer surface of the drum. This mud is introduced into a heated
retort to be reoxidised in order to be used over again.
In operating with this apparatus, the scrap metal, being introduced into the
first drum, is first cleansed from dirt and other impurities by the heated soda
lye in the vat, after which it is conveyed by the shoot into a second drum with
perforated sides, which is not immersed in a vat, but through which a stream
of fresh water is caused to pass continuously so as to thoroughly wash off all
impurities adhering to the metal, which is then conveyed into a third drum, where
the before described process of dissolving the tin from the metal is carried out.
From this drum the scrap metal may be caused to pass through a fourth, fifth, and
any other number of drums until the tin is entirely dissolved, after which the scrap
metal is again conveyed into one or more washing drums so as to thoroughly
cleanse the same, for use in any known manner.
The lye in the vats having become sufficiently saturated with tin in solution,
it is removed and clarified, and it may then be either treated in the known manner
for the production of stannate of soda, or it may be diluted and treated with
carbonic acid for the precipitation of the tin as oxide, leaving carbonate of
soda, which may be separated from the liquor by centrifugal action and washing,
and may then be treated with milk of lime for the production of caustic soda lye
to be used again in the above process.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Charles Denton Abel in the Great Seal Patent Office on the
8th March 1883,
CHARLES DENTON ABEL of N° 28 Southampton Buildings, Chancery Lane in the
County of Middlesex IMPROVEMENTS IN
THE
SEPARATING TIN FROM SCRAP OR WASTE METAL
"
PROCESS AND APPARATUS FOR
A communication to me from
abroad by Friedrich Albert Reinecken and Ludolf Poensgen both of Düsseldorf in
the German Empire.
According to the present invention, the separation of tin from scrap or waste
metal is effected by means of a liquid which dissolves the tin, and by means of a
series of revolving drums through which the metal is made to pass consecutively
and automatically, whereby labor is economised and a very perfect removal of the
tin insured.
The liquid eployed for this purpose is a lye consisting of hydrate of soda or
potash dissolve in water to which oxide of lead (Massicot) has been added to
excess.
The apparatus employed for this purpose is shewn on the accompanying drawing
in which Figs. 1, 2 and 3 shew cross sections of the revolving drums. Fig. 4 a side
view of the framing supporting the same, Fig. 5, a longitudinal section of one of
the drums, Fig. 6 a front view of one of the washing drums, Fig. 7 a sectional plan
of one of the drums and its pan, and Fig. 8 a plan of the framing.
The said lye is placed in a series of vats or receptacles x in each of which is a
cylindrical drum revolving on a horizontal axis C carried in bearings band immersed
to about half its diameter. The vats are heated so as to maintain the lye at about
boiling point either by external fire heat or by steam jackets as shewn or by internal
steam pipes.
The drums have large central openings in their sides which are of perforated
metal; they are supported on their shafts by internal radial arms & situated at one
side thereof so as to leave the other side quite free. The arms have inclined
branches W at their ends, leading towards the free side y, which is connected
thereto by bolts passing through slotted holes vso that the side can be shifted
round somewhat. A series of bars p placed close together in a radial direction, are
passed loosely through holes in the adjustable side y and in the opposite arms d, or
in the other side of the drum, which bars constitute grate-like scoops or blades by
which the scrap metal in the drum is raised up as the drum revolves. In addition
to these bars, plates o are provided which may be inserted behind the bars when it
is desired to accelerate the delivery of the scrap metal from the drum, such delivery
being also regulated by shifting the movable side y of the drum so as to cause the
bars p to assume a more or less oblique position. A series of these drums are
arranged side by side as at Figs. 1, 2 and 3 and between each two is an inclined
shoot R connected to the fixed framing and having at its upper end a flap R, hinged
at r, so arranged as, in one position, to project obliquely into the interior of the drum,
as shewn, and catch the scrap metal carried up by the scoops and convey the same
down the shoot into the next drum. When turned upon its hinge, the flap.prevents
the delivery of the metal into the shoot.
As the drum revolves in the lye of the vat, a chemical reaction takes place

page_text: between the lye and the tin on the scrap metal, the latter becoming dissolved by
the former while lead is deposited from the lye in the form of mud in the drum
and the vat. As a portion of this mud is also deposited on the scrap metal, it is
advisable to place together with the same a quantity of granular metal in the drum,
which, as the latter revolves, has a scouring effect on the scrap metal. The mud
that is deposited in the vat is automatically removed therefrom by hinged scrapers D
on the outer surface of the drum. This mud is introduced into a heated retort to
be reoxidised in order to be used over again.
In operating with this apparatus, the scrap metal, being introduced into the first
drum, Fig. 1, is first cleansed from dirt and other impurities by the heated soda lye
in the vat, after which it is conveyed by the shoot into a second drum Fig. 2, with
perforated sides, which is not immersed in a vat, but through which a stream of
fresh water is caused to pass continuously, so as to thoroughly wash off all
impurities adhering to the metal, which is then conveyed into a third drum, Fig 3,
where the before described process of dissolving the tin from the metal is carried
out. From this drum, the scrap metal may be caused to pass through a fourth,
fifth and any other number of drums, until the tin is entirely dissolved, after
which the scrap metal is again conveyed into one or more washing drums such
as at Fig 2, 80 as to thoroughly cleanse the same, for use in any known
manner.
The lye in the vats having become sufficiently saturated with tin in solution, it
is removed and clarified, and it may then be either treated in the known manner
for the production of stannate of soda, or it may be diluted and treated with
carbonic acid for the precipitation of the tin as oxide, leaving carbonate of soda,
which may be separated from the liquor by centrifugal action and washing, and
may then be treated with milk of lime for the production of caustic soda lye to be
used again in the above process.
The rotation of the drums may be effected by any suitable motor, by means of
endless chains or wire ropes, or they may be driven by toothed or frictional
gearing, as indicated at Fig 5. In general, seven such drums are employed arranged
side by side as described, but a greater or less number may be used, according to
the nature of the metal to be acted upon.
The above described method of operating permits of the separation of the tin
from the iron in an economical and commercial manner, as the apparatus permits
of continuous working, and as all the chemical ingredients employed may be readily
regained.
Having thus described the nature of this invention and in what manner the
same is to be performed, as communicated to me by my foreign correspondents
I claim :-
:-
First. The method of separating tin from other metal or metal scrap wherein
the said metal is treated in a series of revolving drums with a lye consisting of
bydrate of potash or soda, supersaturated with oxide of lead.
Second. In the process referred to in the preceding claim, the described
arrangement whereby the metal, in being conveyed automatically from one drum
to the next one, is operated upon in such manner that in the first drum the metal
is cleansed from adhering impurities, while in the second it is subjected to a washing
operation, after which it is made to pass consecutively through a series of other
drums in which the tin is dissolved therefrom, and lastly, it is subjected to another
washing operation in the last drum.
Third. The construction of drums herein described and shewn in the Drawing,
the drums being immersed to about half their depth in pans filled with the liquid
solvent, in which they are caused to rotate.
Fourth. Constructing the drums referred to in the preceding claims with
radial arms d fixed on the axis to one side of the drum, the opposite side y of
which is made adjustable so as to cause the bars p that forms scoops, to

page_text: assume a more or less oblique position, substantially as and for the purpose
described.
Fifth. The arrangement of the inclined shoot R with hinged plate S for
intercepting at will the passage of the metal from one drum to the other.
In Witness whereof, I the said Charles Denton Abel have hereunto set my
hand and seal this eighth day of March in the year of our Lord One
thousand eight hundred and eighty-three.
CHAS. D. ABEL (L.S.)