Year: 1887

page_text: Date of Application, 10th Feb., 1887
Complete Left, 10th Nov., 1887
Complete Accepted, 10th Feb., 1888
We, JOHN BROCK, Alkali Manufacturer, British Alkali Works, Widnes, Lancashire,
THOMAS MINTON, Works Manager, British Alkali Works, Widnes, Lancashire, do
hereby declare the nature of this invention to be as follows:-
This invention has for its object improvements in filter presses.
The apparatus is designed with a special view to the rapid and complete washing of
precipitates and similar substances so as to remove from them soluble constituents
which are either objectionable or of themselves of value.
In the ordinary filter press the solid and liquid which it is desired to separate is
pumped in a state of sludge between a series of plates; the solid matter remains in
the press and the liquid passes through the filter cloth and down the surfaces
of the various plates of which the filter press is composed. This results in the
spaces intervening between the successive plates being filled up with cakes of the
material.
This arrangement is however defective when it is important that the last traces of
any material that the liquid may hold in solution, should be removed from the solid
material in the press.
Endeavours have been made to wash this solution out by pumping water through
the press whilst the cakes were in it. This method is at the best very tedious, the
water in great part finding its way out of the press without passing through the cake
with the result that the liquors passing away were extremely dilute, and that to obtain
complete washing of the solid cakes great expenditure of water, time and power
wore required.
Our filter press reduces the washing of precipitates to an easy and rapid system.
The machine consists of a cylinder made in two halves, axially so that it can be
opened and closed, the halves joining up quite tight by faced surfaces.
The inner surface of this cylinder is lined with gauze over which is filter cloth kept
in its place either by sewing or rings or both. The outer barrel is pierced at intervals
to allow of the escape of the filtrate.
Through the centre of this cylinder and projecting at each end is a pipe by which

page_text: the feed of material (sludge, etc.,) is supplied. This pipe is perforated all along its
length inside the cylinder with a number of holes to ensure the equal distribution of
the feed and wash water. Each end of the cylinder where this pipe passes through is
furnished with a suitable stuffing box. The cylinder can be caused to revolve on the
supports, and it can at the same time be caused to move axially along the feed pipe
by means of a screw-like slot at the other end to that at which the driving gear is
situate. The space through which this slot causes the cylinder to move should
by preference be rather greater than the distance between the perforations on the
feed pipe.
23
In using this machine the " cream or "sludge," consisting of a precipitate, or
solid in a state of division and solution or liquid generally, is pumped into the
cylinder by way of the feed pipe. The cylinder is at the same time caused to revolve
and by means of the slot is moved backwards and forwards along its axis through a
small distance. Soon the cylinder becomes full of the sludge and the pressure inside
it rises, causing the solution to pass through the filter cloth. This goes on till from
accumulation of the solid material in the cylinder either a cake or at any rate a very
thick sludge remains in the cylinder. Water or weaker liquor is now pumped
into the cylinder, its rotation being continued, till the desired standard of purity
is attained.
Precipitates and such like bodies when in a state of mixture with strong solutions
from which they must be freed, have usually to be washed many times by decantation
before being filter pressed at all. Using this machine however they may be at once
pumped into the cylinder and washed clean with the minimum amount of water,
labour and time.
When the contents of the press are considered to be sufficiently washed, the cylinder
can be opened at the axial flanges, and emptied either by moving the cylinder round
or otherwise.
The cylinder is then closed fastened by the bolts shown or other suitable contrivance,
and is ready for work again.
As the wash water is always delivered from the centre of the cake it has to pass
through the whole of the material lying between its point of issue from the pipe, and
the filtering surface before leaving the press, and therefore fulfills the conditions of
scientifically perfect washing with the minimum of water. This is not found in any
other press as far as we are aware.
D
100
131
1007

page_text: We, JOHN BROCK, Alkali Manufacturer, British Alkali Works, Widnes, Lancashire,
THOMAS MINTON, Works Manager, British Alkali Works, Widnes, Lancashire, 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 has for its object improvements in filter presses.
The apparatus is designed with a special view to the rapid and complete washing of
precipitates and similar substances so as to remove from them soluble constituents
which are either objectionable or of themselves of value.
In the ordinary filter press the solid and liquid which it is desired to separate is
pumped in a state of sludge between a series of plates; the solid matter remains in
the press and the liquid passes through the filter cloth and down the surfaces of the
various plates of which the filter press is composed.
This results in the spaces
intervening between the successive plates being filled up with cakes of the material.
This arrangement is however defective when it is important that the last traces of
any material that the liquid may hold in solution, should be removed from the solid
material in the press.
the
Endeavours have been made to wash this solution out by pumping water through
press whilst the cakes were in it. This method is at the best very tedious, the
water in great part finding its way out of the press without passing through the cake
with the result that the liquors passing away were extremely dilute, and that to obtain
complete washing of the solid cakes great expenditure of water, time and power
were required.
Our filter press reduces the washing of precipitates to an easy and rapid system.
The unachine consists of a cylinder made in two halves, axially so that it can be
opened and closed, the halves joining up quite tight by faced surfaces.
The inner surface of this cylinder is lined with gauze over which is filier cloth.
The outer barrel is pierced at intervals to allow of the escape of the filtrate.
Through the centre of this cylinder and projecting at each end is a pipe by which
the feed of material (sludge etc.) is supplied. This pipe is perforated all along its
length inside the cylinder with a number of holes to ensure the equal distribution of
the feed and wash water. Each end of the cylinder where this pipe passes through is
furnished with a suitable stuffing box. The cylinder can be caused to revolve on the
supports and it can at the same time be caused to move axially to and fro for a small
distance along the feed pipe by means of a screw like slot at the other end to that at
which the driving gear is situate. The space through which this slot causes the
cylinder to move should by preference be rather greater than the distance between
the perforations on the feed pipe.

page_text: 2
In using this machine the " cream or "sludge," consisting of a precipitate, or
solid in a state of division and solution or liquid generally, is pumped into the cylinder
by way of the feed pipe. The cylinder is at the same time caused to revolve and by
means of the slot is moved backwards and forwards along its axis through a small
distance. Soon the cylinder becomes full of the sludge and the pressure inside it
rises, causing the solution to pass through the filter cloth. This goes on till from
accumulation of the solid material in the cylinder either a cake or at any rate a
very thick sludge remains in the cylinder. Water or weaker liquor is now pumped
into the cylinder, its rotation being continued, till the desired standard of purity
is attained.
Precipitates and such like bodies when in a state of mixture with strong solutions
from which they must be freed, have usually to be washed many times by decantation
before being filter pressed at all. Using this machine however they may be at once
pumped into the cylinder and washed clean with the minimum amount of water,
labor and time.
When the contents of the press are considered to be sufficiently washed, the
cylinder can be opened at the axial flanges, and emptied either by moving the cylinder
round or otherwse.
The cylinder is then closed fastened by the bolts shown or other suitable contrivance,
and is ready for work again.
As the wash water is always delivered from the centre of the cake it has to pass
through the whole of the material lying between its point of issue from the pipe,
and the filtering surface before leaving the press, and therefore fulfills the conditions
of scientifically perfect washing with the minimum of water. This is not found in
any other press as far as we are aware.
Figure 1 of the drawings hereunto annexed is a side elevation partly in section and
Figure 2 a plan view of apparatus constructed as above described. Figure 3 is an
end view of the cylinder and its supports.
A is the perforatedcylinder in two halves, with flanges along the edges of the
two halves to admit of their being bolted one to the other. The inner surface of this
cylinder is lined with twilled gauze for the purpose of presenting a corrugated surface
to the face side of the cylinder and so assist the liberation of the filtrate, over which
is placed the filter cloth covering the whole surface, and making a perfectly tight
joint, when screwed down a second sheet of wire gauze is then placed over the cloth
to preserve it, and to protect it in discharging the finished product. B B are end
pieces formed to fit the ends of the cylinder. It is necessary to make a tight joint at
each end, and this is done by two steel hoops, which are fastened with set screws, a
little cement or other material being used between the shell and the twilled gauze so
as to prevent any leakage. Each end piece has a stuffing box at its centre through
which passes the perforated feed pipe C. One end has also upon it a toothed wheel D
by which a revolving motion may be imparted to the cylinder. The other has an
arm E extending from it and carrying a pin which enters the cam groove F formed
around a boss which is upon the feed pipe and gives to the cylinder a to and fro end-
way movement as it rotates. The cylinder is supported by two rings G which
surround it resting on rollers as shown. The axes of these rollers can move a distance
end wise in their bearings so as to allow of endway movement being given to the
cylinder. The rings G are in two halves like the other parts of the cylinder. His
a pinion gearing with and driving the toothed wheel D, this pinion is of greater
length than the toothed wheel so that it may remain in gear with it in spite of the
end way motion of the cylinder.
When the press is to be emptied of material accumulated in it the bolts which
retain the two halves of the cylinder together are taken out and the half of the
cylinder which is uppermost is lifted away-the material can then be broken up
and removed.
In some cases it might be sufficient for the cylinder to be revolved without having
end way notion imparted to it, we however prefer to give to it both a revolving and
endway to and fro motion as above described.

page_text: Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed we declare that what
we claim is :--
1. A filter press consisting of a perforated cylinder made in two or more longi-
tudinal parts lined with filter cloth and with a perforated feed pipe passing through
its centre to supply liquid to be filtered to its interior-and with the cylinder capable
of being revolved or of being revolved and moved end wise to and fro along the feed
pipe substantially as described.
2. The construction of filter presses substantially as herein before described and
illustrated in the drawings hereunto annexed.
Dated this 9th day of November 1887.