IM- PROVEMENTS IN FILTERING APPARATUS AND IN FILTERING MATERIALS
Year: 1878

page_text: LETTERS PATENT to Fancis Henry Atkins and Walter George Atkins, both of
62, Fleet Street, in the City of London, Engineers, for the Invention of "IM-
PROVEMENTS IN FILTERING APPARATUS AND IN FILTERING MATERIALS."
Sealed the 15th Anril 1870 and deted the 18th Decembar 1979
PROVISIONAL SPECIFICATION left by the said Francis Henry Atkins and
Walter George Atkins at the Office of the Commissioners of Patents on the
18th December 1878.
FRANCIS HENRY ATKINS and WALTER GEORGE ATKINS, both of 62, Fleet Street,
in the City of London, Engineers. "IMPROVEMENTS IN FILTERING APPARATUS
AND IN FILTERING MATERIALS."
This apparatus consists of a hollow shaft which is perforated and made to act as
a centre tube for collecting and carrying away the filtered liquid. On this shaft is
fixed a series of hollow discs or pairs of discs combined together, which may be of
various forms, but we find it more advantageous to employ a circular form having
parallel surfaces and the extreme outside circumference closed so that the liquid can
filter through the two sides of each disc but can only escape by passing through the
perforations into the centre shaft.
These discs may be constructed in several ways and of various materials,
according to the kind of filtration required and the nature of the liquid to be filtered.
In some cases we use filter cloth, felt, or other straining material supported on the
hollow discs or pairs of discs of perforated metal, or in other suitable manner. In
some cases we employ discs of wire-work of any desired fineness, according to the
fluid to be filtered. In other cases we employ discs or plates of porous stone or
porous earthenware, or charcoal, coke, or other suitable porous material.
When such stone, earthenware, charcoal, or other plate is used, the disc may either
be in one piece, or several discs may be made in one piece, or when required of large
diameter each disc may be formed in segments and bolted round the centre shaft,
suitable bolts being fastened to the centre shaft and extending to the circumference

page_text: of each disc like spokes of a wheel so that the segments of stone, earthenware, or
charcoal plate may be securely fastened to the above mentioned centre shaft. Each
hollow disc may be filled with charcoal in a granulated form or other suitable
filtering material, and the bolts may be hollow and perforated, or suitable hollow
perforated ribs may be arranged inside each disc for more rapidly conveying the
filtered water to the centre shaft.
The second part of our Invention consists in placing against the outer surface of
each hollow disc, or between the outer surfaces of each pair of discs, one or more
brushes extending from the outer edge or circumference of each disc to the centre shaft,
or the brush or brushes may be continued across the whole surface of the outside of
each disc, passing as near to the centre as the centre shaft will allow. We find it
advantageous to employ those known as tube or twisted wire brushes, and such
brushes may be stationary, or may rotate on their longitudinal axis, or may have a
to and fro motion. The object of these brushes is to cleanse the outer surfaces of
the discs, which is effected by causing the brushes to pass over the discs or by
causing the discs to revolve past the brushes, or both, and when the discs have
completed one revolution every part will thus have been brought into contact with
the brushes and the deposit left by the operation of filtering is thereby removed.
Or sprays of water may be used for cleansing the discs, or the discs may be caused
to revolve rapidly, the deposit being thrown off by centrifugal action.
When plates or discs of stone, earthenware, charcoal, coke, or other suitable
material are employed we use scrapers of iron or other suitable material arranged in
a similar way to the brushes; such scrapers may be either stationary or rotate, or
have a to and fro motion, and they may be used either in addition to the brushes or
without them. The scraping is effected in the same way as the brushing, namely,
by causing the scrapers to pass over the surface of the discs, or by causing the discs to
revolve, or both, and thus every part being gradually brought into contact with the
scrapers the surface is removed to any desired extent. In some cases we employ
scrapers only and no brushes.
In place of using circular discs, the filtering surfaces may be of rectangular or
other forms arranged near together with one channel common to the series for
receiving the filtered water.
Or the filtering discs may be arranged in sets, the brushes being fixed in the form
of arms or wheels on an axis which is central to the entire set of discs and revolve
between the discs to cleanse them.
The third part of our Invention relates to the special preparation of earthenware
or stone when we desire to obtain great purity in filtered water.
For this purpose we take plates, hollow discs, segments of discs, or other forms of
earthenware or stone, except the granular form, that may be desired [for filtering
purposes, and we subject such porous earthenware to a carbonizing process either by
covering it with saw dust or other vegetable or animal matter in a retort and sub-
jecting it to a high temperature. Or the porous earthenware may be saturated
with potroleum, tar, or other carbonaceous liquid and subjected to heat; or the
fumes from carbonaceous matter may be brought into contact with the earthenware
at a high temperature. After being subjected to any one or all of these processes,
the porous earthenware on being removed when cold from the retort will be found
to have a deposit of carbon throughout its porous substance.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Franois Henry Atkins and Walter George Atkins in the Great
Seal Patent Office on the 18th June 1879.
FRANCIS HENRY ATKINS and WALTER GEORGE ATKINS, both of 62, Fleet Street,
in the City of London, Engineers. "IMPROVEMENTS IN FILTERING APPARATUS
AND IN FILTERING MATERIALS."
Our Invention relates, first, to improvements in filtering apparatus, and in order
that our improvements may be clearly understood and readily carried into practice
we will proceed to describe the Drawings hereto annexed.
DESCRIPTION OF THE DRAWINGS.
Figure 1 shows a vertical section of filtering apparatus arranged and constructed
in accordance with the first part of our improvements. a is a hollow shaft supported
in the tank a¹, which shaft is perforated and acts as a centre tube for collecting and
carrying away the filtered liquid. On the shaft a is fixed a series of hollow discs
or pairs of discs b, b, which may be of various forms having parallel surfaces as
shown in Figure 1, or inclined surfaces as shown in Figure 2, in either case the
surface being flat and closed at the outer circumference so that the liquid can filter
through the sides of each pair of discs b into the space between them, and thence
through perforations into the hollow shaft a.
These discs may be constructed in several ways and of various materials,
according to the kind of filtration required and the nature of the liquid to bo
filtered. In some cases we use filter cloth, felt, or other straining material supported
on the hollow discs or pairs of discs of perforated metal, or in other suitable
manner.
In some cases we employ discs of wire work of any desired fineness according
to the nature or condition of the fluid to be filtered.
In other cases we employ discs or plates of porous stone, porous earthenware,
charcoal, coke, or other suitable porous material. When such stone, earthenware,
charcoal, or other filtering plate is used, the double disc may either be in one piece,
or several discs may be made in one piece, as shown in Figures 4 and 5 of the
Drawings. When required of large diameter each double disc may be formed in
segments 1, 2, 3, 4, 5, as shown in Figures 6, 7, and 8, and secured to the centre
shaft a by means of a tyre in which tightening bolts 61, see Figure 8, are secured.
In order that the tyre and segments may be the more easily and firmly secured to
the centre shaft, iron rods or long bolts b', Figures 6 and 8, are fixed in the said
shaft and extend to the outer circumference of the double disc. Each segment being
formed like a hollow box, no radial water tight joints are required, but by means of
india rubber or other suitable material inserted between the other joints at x, x, x,,
and where the inner segments abut upon the centre tube or shaft a; when the
bolts b', 62, are screwed through the tyre the joints x, x, x, are compressed and made
water tight.
We do not confine ourselves to the forms of segments shown, as any other con-
venient form may be employed.
These segments may be made and arranged so as to form either flat or inclined
surfaces or sides as shown in Figure 7.
Each hollow disc b may be filled with charcoal in a granulated form, or with
other suitable filtering materials, and the bolts may be hollow and perforated, or
suitable hollow perforated ribs may be arranged inside each disc for more rapidly
conveying the filtered water to the centre hollow shaft.
The second part of our Invention consists in placing and arranging against or in
contact with the outer surface of each hollow disc, or between the outer surfaces of

page_text: each pair of discs b, one or more brushes c extending from the outer edge or
circumference of each disc to the centre shaft, as shown in Figure 3; or the brush
or brushes o may be continued across the whole surface of the outside of each
disc, as shown in Figures 1 and 6, passing as near to the centre as the centre
shaft will allow.
We find it advantageous to employ those brushes known as tube or twisted wire
brushes, or the brushes may be made of wire, india rubber, or other suitable material,
and such brushes may be stationary, or may rotate on their longitudinal axis, or
may have a to and fro motion.
The object of these brushes c is to cleanse the outer surfaces of the discs, which
is effected by turning the crank handle fixed on the axis d (which may be other-
wise actuated, Figures 1 and 2) on which are mounted the bevil wheels d¹, each of
which takes into and drives a pinion d² mounted on the axis of each brush c, each
brush being arranged between and in contact with the outer surface of two double
discs.
On the axis d is also mounted a bevil wheel d³ which takes into and drives a
pinion d on the axis of the worm do which actuates the worm wheel as which is
securely fixed upon the central hollow shaft a.
When the crank handle on the axis d is turned each brush c is caused to revolve on
its longitudinal axis at the same time the discs b on the central shaft a slowly
revolve, and thus every part of the surface of the discs is brought in contact with
the rotating brush and the deposit left by filtration is thereby removed.
Instead of rotating, the brushes c may have a to and fro motion communicated
to them by each brush being attached to an eccentric mounted on the axis d, or the
axis & may consist of one long crank shaft to which each brush c may be attached,
or the brushes may be stationary and the discs 6 arranged to revolve against them,
the mechanism for actuating the brushes being dispensed with.
The advantage of forming the outer surface or sides of the discs b inclined is that
the brushes between the external surfaces of such discs may be conical, and as they
wear away by cleansing the surface, on being placed a little lower, they will again
come in contact with the surfaces of the discs and again be available for cleansing
purposes.
When plates or discs of stone, earthenware, charcoal, coke, or other suitable
material are employed, we use scrapers of iron or other suitable material arranged
to act in a similar manner to the brushes.
Such scrapers may be either stationary, or rotate, or have a to and fro motion,
and they may be used either in addition to the brushes or without them. The
scraping is effected in the same way as the brushing, namely, by causing the scrapers
to pass over the surface of the discs, or by causing the discs to revolve, or for both
to revolve, and thus every part being gradually brought into contact with the
scrapers the surface is removed to any desired extent.
In some cases we employ scrapers only and no brushes.
In place of using circular discs the filtering surfaces may be of rectangular or
other form arranged near together with one outlet channel common to the series
for receiving the filtered water.
Figures 9 and 10 show a series of double or hollow stationary filtering surfaces e
of rectangular form closed at the ends and top. A series of brushes fis arranged,
one brush between and in contact with each pair of filtering surfaces e, the ends of
the brushes being mounted in a frame f¹. The whole frame f¹ is raised and
lowered from time to time as required, and thus the deposit on the filtering surfaces
is removed.
Figures 11, 12, and 13 show circular stationary filtering surfaces g formed in hollow
segments with passages at g' for the filtered water to pass away into a channel h at
the bottom common to the series. A circular opening is left in the centre through
which a shaft i is passed supported in bearings at each end. On this shaft a brush i'
is mounted between and in contact with each pair of filtering surfaces. When.

page_text: this shaft is caused to revolve, the brushes ¹act so as to cleanse the filtering
surfaces.
Or the filtering discs may be arranged in sets, the brushes being arranged in the
form of arms, or wheels, or an axis which is central to the entire set of discs, and
revolves between the discs to cleanse them.
Figures 14 and 15 show an elevation and plan of a series of double filtering
discs b mounted on four centre tubes or shafts a. In this case the cleansing is
effected by a brush c (or it may be a scraper) in the form of a wheel fixed between
and centrally to the four centre shafts a of the filtering discs and in contact with
their outer surfaces. By suitable gearing the circular or wheel shaped brushes care
caused to revolve rapidly, and the discs 6 are caused to revolve slowly, and thus the
entire set of filtering surfaces is cleansed at one operation, or the discs b may revolve
and the brushes remain stationary.
We do not confine ourselves to the set of four filtering surfaces c, as any suitable
number may be employed.
In all cases scrapers may be employed in place of brushes.
The third part of our Invention relates to the special preparation of earthenware
or stone when we desire to obtain great purity in filtered water.
For this purpose we take plates, hollow discs, segments of discs, or other forms of
porous earthenware or stone (except the granular form) that may be desired for
filtering purposes, and we subject such porous earthenware or stone to a carbonizing
process either by covering it with saw dust or other vegetable or animal matter in
a retort, and subjecting it to a high temperature.
Or the porous earthenware or stone in various forms (except the granular form)
may be saturated with petroleum, tar, or other carbonaceous liquid, and subjected to
heat to carbonize it.
Or the fumes from carbonaceous matter may be brought into contact with the
earthenware or stone at a high temperature. After being subjected to any one or
all of these carbonizing processes the porous earthenware or stone on being removed
from the retort when cold will be found to have a deposit of carbon throughout its
porous substance, thus rendering it very suitable for filtering purposes and for use
in carrying out the other parts of our improvements as previously described.
Having thus described the nature of our improvements, and the manner of per-
forming or carrying the same into practice, we would remark that we do not limit
ourselves to the exact details herein shown and described so long as the novel features
of our Invention are retained, neither do we claim any of the parts separately which
are well known and in common use, but what we claim is,-
First. The improved arrangement and construction of filtering apparatus in
which a series of porous hollow discs bare employed mounted upon a central
hollow shaft or axis a, substantially as herein before described, and shown in the
Drawings annexed.
Secondly. The improved arrangement and construction of filtering apparatus in
which a series of porous hollow discs or other hollow chambers b formed with
straight or inclined sides are mounted upon a central hollow axis in a tank or
reservoir in combination with a series of brushes, scrapers c, or their equivalents for
cleansing the surfaces of the porous hollow discs from time to time as required, all
arranged to act substantially in the manner herein before described with reference
to Figures 1, 2, and 3 of the Drawings hereto annexed.
Thirdly. We claim the construction and application of hollow porous discs with
straight or inclined surfaces for filtering purposes made either in one piece or with
several of such discs combined, or by making them from a number of segments
combined together, substantially as herein before described with reference to
Figures 4, 5, 6, 7, and 8 of the Drawings annexed.
Fourthly. We claim the use and application of brushes c for cleansing the
exterior surfaces of the porous hollow discs b or other hollow filtering surfaces,
substantially in the manner herein before described, and shown in the Drawings
annexed.

page_text: Fifthly. We claim the improved arrangement and construction of filtering
apparatus, substantially as herein before described with reference to Figures 9, 10,
11, 12, 13, 14, and 15 of the Drawings hereto annexed.
Sixthly. We claim the subjecting of plates, hollow discs, segments of discs, or
other forms (except the granular form) of porous earthenware or stone used for
filtering purposes to a carbonizing process, substantially in the manner and for the
purposes hereinbefore described.
In witness whereof, we, the said Francis Henry Atkins and Walter George
Atkins, have hereunto set our hands and seals, this Eighteenth day of
June, in the year of our Lord One thousand eight hundred and seventy
F. H. ATKINS. (L.S.)
W. G. ATKINS. (L.S.)