IMPROVEMENTS IN CENTRI- FUGAL MACHINES, AND IN THE SEPARATION OF SOLID AND LIQUID MATTERS BY MEANS THEREOF
Year: 1881

page_text: LETTERS PATENT to Bernhard Heinrich Remmers, of Glasgow, in the County
of Lanark, North Britain, for an Invention of "IMPROVEMENTS IN CENTRI-
FUGAL MACHINES, AND IN THE SEPARATION OF SOLID AND LIQUID MATTERS
BY MEANS THEREOF." A communication from abroad by Wilhelm Angele, of
Berlin, in the Empire of Germany.
PROVISIONAL SPECIFICATION left by the said Bernhard Heinrich Remmers
at the Office of the Commissioners of Patents on the 22nd April 1881.
BERNHARD HEINRICH REMMERS, of Glasgow, in the County of Lanark, North
Britain. "IMPROVEMENTS IN CENTRIFUGAL MACHINES, AND IN THE SEPARATION
OF SOLID AND LIQUID MATTERS BY MEANS THEREOF." A communication from
abroad by Wilhelm Angele, of Berlin, in the Empire of Germany.
The nature of this Invention is to effect certain improvements in the machines
commonly called centrifugal machines used for separating solid particles of material
from liquid adhering to or intermixed with them, and for filtering and con-
solidating such solid particles of material when diffused in a liquid, and to improve
the method of filtering by such machines.
.
The principal object of the said improvements is to render such machines
applicable for economical use in certain processes and manufactures in which
attempts to apply them successfully have hitherto failed, such as, for example, in
the drying of starch, faccula, and similar materials, but some or even all of the
improvements are generally applicable.
The ordinary centrifugal machine consists of an outer stationary casing, and of
an internal drum of perforated metal or wire work, which latter is fixed on a
central spindle, and is capable of being rotated with great velocity. This form of
the machine answers very well for the drying or filtration of substances whose
crystals or particles are larger in dimension than the dimensions of the perforations
or interstices in the revolving drum; but for substances whose crystal or particles
are of smaller dimensions than the finest perforations in metal, or the smallest
reticulations in wirework hitherto used, the machine has entirely failed, because
LD 471

page_text: great numbers of the said smaller particles escape along with the liquor, and it is
only after some time when a crust or coating of larger particles, if such happen to
exist in the liquor, has been formed over the perforations or interstices that the
remaining crystals or particles of smaller dimensions are retained. Instead of
having the revolving drum perforated or reticulated I make this drum without
perforations or reticulations, and either with or without movable or fixed splash
boards to break the rotary movement of the fluid when the machine is being
stopped. After the material to be operated on in a drum of this kind (such as a
liquor, containing starch) has been run into the drum and the drum set in motion
for such time as experience of the particular material under treatment shall
determine, it will be found on stopping the machine that the particles of the
substance have arranged themselves in concentric layers upon the interior side or
wall of the drum, according to their sizes and gravities, the heavier or grosser
nearest to the metal, and the lighter or finer sized over them. The liquid matter.
remaining in the centre is run off by a plug hole in the bottom of the drum. This
arrangement of the solid particles into layers according to size and weight is in
many cases, as, for example, in that of filtering starch, of great importance, as it
frequently separates into layers superior and inferior qualities, which are connected
with greater or less weight or size of particle. It is also convenient for the
separation of two or more different substances having different specific gravities
when the size of particle is tolerably uniform.
The ordinary perforated drum may have attached to its outside a tight fitting
metallic or other casing, capable of being moved or adjusted by screws or other
arrangement in such a manner as when required to cover and close the holes of
the drum, so as to prevent any liquid or other matter from escaping, and also
capable of being when required moved and adjusted to and in such a different
position as will allow free exit or escape for the liquid from the outside of the
drum. The same machine can thus at pleasure be made to work either on the
principle of ejecting the liquor through the perforations, or on that of depositing
the solid material in layers against the walls of the drum, the liquor being
afterwards drawn off through the plug hole. There may be various mechanical
arrangements for making the outer casing alternately mask and unmask the
perforations as required. The outer casing may be perforated with holes, which
when it is in one position shall with the greatest exactitude practicable coincide
with the holes in the drum, while in another position the holes of the drum shall
be covered and closed by the solid or now perforated metallic portions of the
casing. Or the casing need not be perforated, but may be made so as to slip or
slide tightly over the drum when it is required to close the perforations, and so
that it may be removed when it is desired to open them. If the metallic or other
rigid casing do not fit the drum exactly the space between may be fitted with a
setting of paraffin, grease, or other similar material, which will not affect or be
affected by the material to be operated on. The casing need not be of rigid
material, but may in many cases consist of an elastic impermeable material, such
as india-rubber and the like, which may when required be fitted tightly round
the outside of the drum; or this elastic casing may be used between the drum and
an outer rigid casing. When I use the perforated drum without any casing,
closing the perforations for the filtration of very fine particles from the liquor in
which they are contained, I line or cover the inside of the drum with cloth, silk,
or other similar fabric of any kind, such as is used in filter presses, and of any
degree of closeness in the fibres or texture, and in one or more pieces or thicknesses,
according to the nature of the material to be operated on. In some cases I have
used unsized paper lining with success, and any felted material of an analogous
character to felt or paper which possesses the power of absorbing moisture and
permitting it to pass through may be used instead of textile fabrics, where the
character of the liquor and the particles to be filtered may require it. The lining
may be fixed at the top and bottom of the perforated wall of the drum by hoops
of elastic metal cut at one point, so that they may be compressed while being

page_text: inserted, and may on expanding keep the lining tense and in its place. Or any
other method of fixing may be employed, as, for example, by folding the cloth
over a framework of wirecloth or perforated metal, or by fixing the cloth at the
bottom between the edge of the web of the mantle, hereinafter mentioned, and
the floor of the drum, and at the top by making the edge of the cloth fold over the
edge of the drum, and be fastened there by the cover of the drum, which is
screwed or otherwise fastened on to the drum.
I also adjust to the drum an arrangement by which the process of moulding the
filtered material into forms suitable for the market, or for further manipulation
may be conjoined with the process of filtration, and go on pari passu, therewith
being performed by the drum itself as it rotates. This arrangement consists
essentially in forming by a series of removable partitions, projecting when in
position from the inside of the wall of the drum towards the centre at such
distances from each other as may be required, a series of chambers or moulds into
which the rotation of the drum throws or forces the filtered material which thus
receives and, retains the form of the chamber or mould formed by the partitions
and the segments into which the wall of the drum is divided by them. It is
obvious that this arrangement admits of a great variety in the method of carrying
it into effect, and in its details. The methods prefer are the following:-I form
a metallic mantle of sheet metal of such a shape that it will fit down over the
spindle and its casing, and spread itself out over and cover exactly the floor of the
drum. The mantle is not permanently fixed, and in most cases will keep its
position by its own weight, but if fixed in any way it must be so that it may be
unfastened and lifted out of the drum at the end of the operation. The web or
sole-plate which spreads out over the floor of the drum carries on it the vertical
partitions before mentioned, which are screwed into it, so that when the mantle
and web are in their proper positions in the drum the partitions shall be arranged
all round the wall of the drum, projecting from the wall towards the centre. The
partitions may be flat strips of metal, in which case the mould formed by any two
of them and the segment of drum wall intercepted between them will be wider at
the wall than it is at the parts nearer the centre of the drum. The partitions how-
ever may be made of a wedge shape instead of flat, the base of the wedge being next
the wall of the drum and the edge next the centre, so that the two walls of each of
the several chambers may be parallel. The base of each of the wedges is moulded
into the form of a segment of a circle so as to fit exactly when in position to the
inner wall of the drum. The mantle web and partitions together with the filtered
and consolidated material which has been deposited between the partitions during
the rotation of the drum are lifted out when the operation is finished, and the
blocks of moulded material are then pushed out from between the partitions. Or
by another modification of the arrangement the mantle and web may be inserted,
and then a separate framework carrying the partitions may be inserted, so that
the partitions shall occupy the position above described. This framework consists
of two or more metal rings placed horizontally one above the other at requisite
distances (like the hoops on a cask), to the outside of which the partitions are
soldered vertically by their edges in such a way that their planes in a horizontal
section would if continued meet at the centre of the horizontal section of the drum.
The diameter of the rings and the partitions are made of such dimensions that the
vertical edges of the partitions shall, when the framework is placed in proper
position in the drum, fit close to the wall of the drum, and the framework may be
fixed by a variety of obvious contrivances. The framework is inserted within the
drum so that it rests on the web of the mantle, and may when the moulds are
full be lifted out along with the mantle and cleared of its blocks as before
mentioned.
Instead of soldering the partitions to the outside of the rings the rings may be
separate from the partitions, and made of an elastic metal, and cut at one point, so
as to permit of their being compressed in order to be put into position, after which
they will expand, as before mentioned. The edges of the partitions next the centre

page_text: are provided with a series of notches at equal distances in all the partitions from
the top or bottom of the partitions, into which notches the cut rings may be
inserted when the partitions are in their proper position in order to hold them
there, and there may be vertical slots in or formed by two vertical strips of metal
on the wall of the drum to receive the external vertical edges of the flat partitions,
or to receive vertical flanges cast on the convex face of the wedge shaped partitions,
so that the partitions fitted into the slots may by the clastic pressure of the cut
rings inserted into the notches be held in their proper positions. Where the
machine is to be constantly used for turning out blocks of the same material, and
it is desired to have the outer side of the block plain instead of convex, the drum
instead of being circular may be made hexagonal, octagonal, or with any other
number of polygonal faces which the number of chambers or moulds required may
determine. Where the drum is made to work without perforations there will be a
hole in the web corresponding to the plug hole in the bottom of the drum through
which the liquor may be let out.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Bernhard Heinrich Remmers in the Great Seal Patent Office on
the 21st October 1881.
BERNHARD HEINRICH REMMERS, of Glasgow, in the County of Lanark, North
Britain. " IMPROVEMENTS IN CENTRIFUGAL MACHINES, AND IN THE SEPARATION
OF SOLID AND LIQUID MATTERS BY MEANS THEREOF." A communication from
abroad by Wilhelm Angele, of Berlin, in the Empire of Germany.
The nature of this Invention is to effect certain improvements in the machines
commonly called centrifugal machines used for separating solid particles of material
from liquid adhering to or intermixed with them, and for filtering and consolidating
such solid particles of material when diffused in a liquid, and to improve the
method of filtering by such machines.
The principal object of the said improvements is to render such machines
applicable for economical use in certain processes and manufactures in which
attempts to apply them successfully have hitherto failed, such as for example in
the drying of starch faccula and similar materials, but some or even all of the
improvements are generally applicable.
•
The ordinary centrifugal machine consists of an outer stationary casing and of
an internal drum of perforated metal or wire-work, which latter is fixed on a
central spindle, and is capable of being rotated with great velocity.
This form of machine answers very well for the drying or filtration of substances
whose crystals or particles are larger in dimensions than the perforations or
interstices in the revolving drum. But for substances whose crystals or particles
are of smaller dimensions than the finest perforations in metal, or the smallest
reticulations in wire-work hitherto used, the machine has entirely failed, because
great numbers of the said smaller particles escape along with the liquor, and it is
only after some time when a crust or coating of larger particles, if such happen
to exist in the liquor, has been formed over the perforations or interstices that the`
remaining crystals or particles of smaller dimensions are retained.
And in order that the said Invention, and the manner of performing the same
may be properly understood, I shall now proceed to describe the said improvements
as applied to such centrifugal machines.
Instead of having a revolving drum perforated or reticulated as in the ordinary
construction of centrifugal machines, I make this drum without perforations or
reticulations, and either with or without movable or fixed splash boards to break
the rotary movement of the fluid when the machine is being stopped. After the
material to be operated on in a drum of this kind (such as liquor containing starch)
has been run into the drum, and the drum set in motion for such time as experience
of the particular material under treatment shall determine, it will be found on
stopping the machine that the particles of the substance have arranged themselves
in concentric layers upon the interior side or wall of the drum, according to their
sizes and gravities, the heavier or grosser nearest to the metal, and the lighter or
.finer sized over them. The liquid matter remaining in the centre is run off by a
plug hole in the bottom of the drum. This arrangement of the solid particles into
layers according to size and weight is in many cases, as for example in that of
filtering starch, of great importance, as it frequently separates into layers superior
and inferior qualities which are connected with greater or less weight or size of
particle. It is also convenient for the separation of two or more different
substances having different specific gravities when the size of particle is tolerably
uniform.
The ordinary perforated drum may have attached to its outside a tight fitting
metallic or other casing capable of being moved or adjusted by screws or other

page_text: arrangement in such a manner as when required to cover and close the holes of
the drum, so as to prevent any liquid or other matter from escaping, and also
capable of being when required moved and adjusted to and in such a different
position as will allow free exit or escape of the liquid from the inside of the
drum.
The same machine can thus at pleasure be made to work either on the principle
of ejecting the liquor through the perforations, or on that of depositing the solid
material in layers against the walls of the drum, the liquor being afterwards drawn
off through the plug hole.
There may be various mechanical arrangements for making the outer casing
alternately mask and unmask the perforations as required. The outer casing may
be perforated with holes, which when it is in one position shall, with the greatest
exactitude practicable, coincide with the holes in the drum, while in another
position the holes of the drum shall be covered and closed by the solid or now
perforated metallic portions of the casing. Or the casing need not be perforated,
but may be made so as to slip or slide tightly over the drum when it is required to
close the perforations, and so that it may be removed when it is desirable to open
them. If the metallic or other rigid casing do not fit the drum exactly, the space
between may be filled with a setting of paraffin, grease, or other similar material
which will not affect or be effected by the material to be operated on.
The casing
need not be. of rigid material, but may in many cases consist of an elastic
impermeable material, such as india-rubber and the like, which may when required
be fitted tightly round the outside of the drum, or the elastic casing may be used
between the drum and an outer rigid casing. When I use the perforated drum
without any casing closing the perforations for the filtration of very fine particles
from the liquor in which they are contained, I line or cover the outside of the drum
with cloth, silk, or other similar fabric of any kind, such as are used in filter
presses, and of any degree of closeness in the fibres or texture, and in one or more
pieces or thicknesses according to the nature of the material to be operated on.
In some cases I have used unsized paper lining with success, and any felted
material of an analogous character to felt or paper which possesses the power of
absorbing the moisture and permitting it to pass through may be used instead of
textile fabrics where the character of the liquor and the particles to be filtered may
require it. The lining may be fixed at the top and bottom of the perforated wall
of the drum by hoops of elastic metal cut at one point, so that they may be com-
pressed while being inserted, and may on expanding keep the lining tense and in
its proper place.
Or any other method of fixing may be employed, as for example, by folding the
cloth over a framework of wire-cloth or perforated metal, or by fixing the cloth at
the bottom between the edge of the web of the mantle hereinafter mentioned
and the floor of the drum, and at the top by making the edge of the cloth fold
over the edge of the drum, and be fastened there by the cover of the drum which
is screwed or otherwise fastened on to the drum.
I also adjust to the drum an arrangement by which the process of moulding the
filtered material into forms suitable for the market or for further manipulation
may be conjoined with the process of filtration, and go on pari passu therewith,
being performed by the drum itself as it rotates. This arrangement consists
essentially in forming by means of a series of removable partitions, projecting
when in position from the inside of the wall of the drum towards the centre at
such distances from each other as may be required, a series of chambers or moulds
into which the rotation of the drum throws or forces the filtered material, which
thus receives and retains the form of the chamber or mould formed by the
partitions, and the segments into which the wall of the drum is divided by them.
:-
It is obvious that this arrangement admits of a great variety in the method of
carrying it into effect and in its details. The methods I prefer are the following:-
I form a metallic mantle of sheet metal, of such a shape that it will fit down over
the spindle and its casing and spread itself out over and cover exactly the floor of

page_text: the drum. The mantle is not permanently fixed, and in most cases will keep its
position by its own weight, but if fixed in any way, it must be so that it may be
unfastened and lifted out of the drum at the end of the operation. The web or
sole-plate which spreads out over the floor of the drum carries on it the vertical
partitions before mentioned, which are screwed into it, so that when the mantle
and web are in their proper positions in the drum, the partitions shall be arranged all
round the wall of the drum projecting from the wall towards the centre. The
partitions may be flat strips of metal, in which case the mould formed by any
two of them and the segment of drum wall intercepted between them will be
wider at the wall than it is at the parts nearer the centre of the drum. The
partitions however may be made of a wedge shape instead of flat, the base of the
wedge being next the wall of the drum; and the edge next the centre, so that the
two walls of each of the several chambers may be parallel. The base of each of
the wedges is moulded into the form of a segment of a circle, so as to fit exactly
when in position to the inner wall of the drum. The mantle web and partitions,
together with the filtered and consolidated material which has been deposited
between the partitions during the rotation of the drum, are lifted out when the
operation is finished, and the blocks of moulded material are then pushed out from
between the partitions.
Or by another modification of the arrangement the mantle and web may be
inserted, and then a separate framework carrying the partitions may be inserted,
so that the partitions shall occupy the position above described. This framework
consists of two or more metal rings placed horizontally one above the other at
requisite distances (like the hoops on a cask), to the outside of which the partitions
are soldered vertically by their edges in such a way that their planes in a horizontal
section would if continued meet at the centre of the horizontal section of the drum.
The diameter of the rings and the partitions are made of such dimensions that the
vertical edges of the partitions shall, when the framework is placed in proper
position in the drum, fit close to the wall of the drum, and the framework may be
fixed by a variety of obvious contrivances. The framework is inserted within tho
drum, so that it rests on the web of the mantle and may when the moulds are full
be lifted out along with the mantle and cleared of its blocks as before mentioned.
Instead of soldering the partitions to the outside of the rings, the rings may be
separate from the partitions and made of an elastic metal and cut at one point, so
as to permit of their being compressed in order to be put into position, after which
they will expand as before mentioned. The edges of the partitions next the centre
are provided with a series of notches at equal distances in all the partitions from
the top or bottom of the partitions, into which notches the cut rings may be
inserted when the partitions are in their proper positions in order to hold them
there;
and there may be vertical slots in or formed by two vertical strips of metal
on the walls of the drum to receive the external edges of the flat partitions, or to
receive vertical flanges cast on the convex face of the wedge shaped partitions, so
that the partitions fitted into the slots may by the elastic pressure of the cut rings
inserted into the notches be held in their proper positions. Where the machine is
to be constantly used for turning out blocks of the same material, and it is desired
to have the outer side of the block plane instead of convex, the drum instead of
being circular may be made octagonal, or with any other number of polygonal faces
which the number of chambers or moulds required may determine. Where the
drum is made to work without perforations, there will be a hole in the web
corresponding to the plug hole in the bottom of the drum, through which the liquor
may be let out.
Having thus particularly described the said Invention, and the manner of
performing the same, I have to state that what I consider novel and original, and
therefore claim as the Invention secured to me by the hereinbefore in part recited
Letters Patent is,―
First. The separating in the manner herein set forth of solid and liquid matters
by means of centrifugal machines, substantially such as are herein described, in

page_text: which the revolving drum is formed with a solid or unpierced outer shell; or in
which such drum is made of wire cloth or perforated metal, and fitted with a
movable casing which masks or unmasks the perforations; or in which the drum is
covered with a lining of cloth or other filtering medium; or in which division
chambers or moulds are formed or fitted within the solid or perforated drum to
shape or mould the solid material retained.
Second. The construction of centrifugal machines for separating solid and liquid
matters with the outer shell of the revolving drum formed of solid or unpierced
metal, with or without splash boards, and with a plug in the bottom for the with-
drawal of the liquid after separation, substantially as and for the purposes herein
set forth.
Third. The construction, substantially as and for the purposes herein set forth,
of centrifugal machines for separating solid and liquid matters, in which the
perforated revolving drum is fitted with a movable cover or casing arranged to
mask and unmask the perforations.
Fourth. The arrangement in and application to centrifugal machines for separating
solid and liquid matters of a lining or covering of cloth or other filtering medium,
substantially as and for the purposes herein set forth.
1
Fifth. The construction and arrangement, substantially as herein described, in
centrifugal machines for separating solid and liquid matters of fixed or movable
divisions fitted within the solid or perforated revolving drum to shape the solid
material retained into blocks.
In witness whereof, I, the said Bernhard Heinrich Remmers, have hereunto
set my hand and seal, this Twentieth day of October, in the year of our
Lord One thousand eight hundred and eighty one.
Witness,
WALLACE FAIRWEATHER, C.E.,
-96, Buchanan Street,
Glasgow.
B. H. REMMERS. (L.S.)