IMPROVEMENTS IN FILTERING AND DEPURATING FLUIDS
Year: 1859

page_text: LETTERS PATENT to John Marshall, junior, of Selby, in the County of
York, Gentleman, for the Invention of "IMPROVEMENTS IN FILTERING
AND DEPURATING FLUIDS."
Sealed the 19th October 1859, and dated the 23rd April 1859. .
PROVISIONAL SPECIFICATION left by the said John Marshall at the
Office of the Commissioners of Patents, with his Petition, on the
23rd April 1859.
I, JOHN MARSHALL, junior, of Selby, in the County of York, Gentleman.
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
FILTERING AND DEPURATING FLUIDS," to be as follows:-
This Invention appliesto an arrangement for filtering and depuratingfluids,
and consists, in the first place, of a cylinder of suitable size and strength to
hold the liquid to be operated on. The cylinder is constructed with an
aperture at top, through which it is filled, and suitable fastenings to secure
it when charged. At the bottom is an opening to admit of fluid being forced
in by means of an ordinary force pump. In operating on oleaginous and
resinous fluids of a specific gravity less than water I employ water in the force
pump direct through the aperture in the lower part of the cylinder, and when
the oleaginous or resinous fluid which floats above the water has been all
forced out of the cylinder into the filters I draw off the water by a suitable
tap, and recharge the cylinder. In filtering other fluids than those herein-

page_text: before described I avail myself of the force pump with water, or where it can
be conveniently employed, the water from the main of the public supply, but
in this case, as the water might commingle with the fluid to be acted on I
adapt inside the cylinder a bag of waterproof material, somewhat larger than
the cylinder, the top of which bag is connected with the top of the cylinder
(so that the fluid to be depurated flows into the bag) and also with the pipe
leading to the filters, or I reverse this arrangement and allow the water to
flow into the flexible bag, which, in that case, is open at the bottom to receive
the water, and with the discharge pipe,so that the bag may be emptied when-
necessary to recharge the cylinder. From the top of the cylinder, but below
the valve which closes it, a pipe leads to the filters, the capacity of which may
be increased or decreased at pleasure by the use of a greater or less number
of duplicate parts of which it is composed. These filters I construct of cast
iron boxes of two kinds, but both of the same form in plan, and provided
with lugs to allow of bolts passing through and connecting a series together.
These boxes are open at the sides, and when connected together are arranged
so that alternately there will be a box covered on both sides with filtering
material, held down by wire gauze or other convenient substitute, both of
which overlap the box so as to make a secure joint, and a box with cross
partitions flush with the face of the otherbox to afford support tothe adjacent
filtering material; into this second box, the fluid, as it filters, flows and escapes
into a proper receptacle. Each partition box has a filter box on each side,
and so on alternately. The centre box may be cast with gudgeons to
admit of the series of filters being placed on standards. The discharge pipe
from the cylinder enters the central box covered on each side with filtering
material, and through this it percolates before it escapes into the filter boxes.
Branch pipes convey the fluid to the other filter boxes, all of which,if desired,
may be charged with ingredients to act chemically on the filtering fluid.
Instead of making the discharge boxes of iron, wood cut to to the length and
breadth of the filtering boxes may be employed. This is grooved on each side,
avoiding only that part which impinges on the edge of the filter boxes, and
which part must be planed true to make a perfect joint. Over the grooves
and overlapping the wood, wire gauze or suitable material is fastened to hold
the filtering material on the boxes in a firm position, and to prevent it from
being forced into the grooves in the wood. From these grooves small per-
forations through the edges of the wood allow the filtered fluid to escape.
For cleaning the surface of the filtering material without detaching the
parts of the filter I employ scrapers, which lie in the filtering boxes and are
made to receive rods, which are passed down through holes in the upper part

page_text: of the filter boxes, and screw into their resp ctive scrapers. The scrapers
then being drawn up and down over the filtering surfaces remove the deposit
collected thereon, which, when accumulated to any extent, may be run off
through suitable discharge pipes. These pipes and the openings for the
insertion of the scrapers must then be closed previously to recommencing the
filtering operation. In operating on any oleaginous fluids where a very large
portion of water remains I prefer to cast the boxes with one side only open;
this is covered with filtering material and secured as described. The box
then rests so that the fluid escapes upward through the filtering strata, and the
water separated as the oil escapes through the filter falls to the bottom of
the box, from which it may be occasionally removed by a suitable tap.
In filtering fluids comparatively valueless, and where the object is to
preserve the soluble portion, the cylinder may be dispensed with and the
fluid led at once to the filters. This may in any case be adopted,. but I
prefer, except in the case last described, to adopt a cylinder. This may
have a kind of cupola above the discharge pipe, which filled with air
moderates by its elasticity the stroke of the force pump.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Marshall in the Great Seal Patent Office on the
22nd October 1:59.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
MARSILALL, junior, of Selby, in the County of York, Gentleman, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-third day of April, in the year of our Lord
One thousand eight hundred and fifty-nine, in the twenty-second year of Her
reign, did, fer Herself, Her heirs and successors, give and grant unto me,
the said John Marshall, junior, Her special license that I, the said John
Marshall, junior, my executors, administrators, and assigns, or such others as
I, the said John Marshall, junior, my executors, administrators, and assigns,
should at any time agree with, and no others, from time to time and at all
times thereafter during the term therein expressed, should and lawfully might
make, use, exercise, and vend, within the United Kingdom of Great Britain
and Ireland, the Channel Islands, and Isle of Man, an Invention for "IM-
PROVEMENTS IN FILTERING AND DEPURATING FLUIDS," upon the condition (amongst
others) that I, the said John Marshall, junior, by an instrument in writing

page_text: under my hand and seal, should particularly describe and ascertain the
nature of the said Invention, and in what manner the same was to be per-
formed, and cause the same to be filed in the Great Seal Patent Office within
six calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said John Marshall, junior, do hereby declare
the nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, reference being had to the Drawing hereunto annexed, and to the
letters and figures marked thereon (that is to say):—
This Invention of improvements in filtering and depurating fluids applies
to an arrangement of apparatus for filtering and depurating fluids of various
kinds, and consists, in the first place, of a cylindrical or other conveniently
shaped reservoir, of suitable size and strength to hold the liquid to be operated
on.
And, secondly, in a novel arrangement or construction of filtering
surfaces through which the fluid is forced from the vessel or reservoir.
In the accompanying Drawings Fig. is a sectional view of the entire
apparatus arranged for filtering saccharine, oleaginous, or any other liquids
required to undergo such process. A is a vessel or reservoir constructed with
an aperture a at top, through which it is filled with the liquid to be operated
on, together with any chemical agent required to act on the liquid. This
opening a is provided with suitable fastenings to close and secure it when the
vessel or reservoir A is charged. At the bottom of the vessel A is another
opening communicating with a pipe b, to admit of water or other fluid being
forced in by means of an ordinary force pump or other mechanical contrivance.
In operating on oleagnious and resinous liquids or fluids, ofa specific gravity
less than water, I obtain pressure from a force pump, using either the
oleaginous or resinous fluid or water direct through the pipe b, and the
aperture in the lower part of the vessel A, and when (where water is thus
employed) the oleaginous or resinous fluid which floats above the water has
been all forced out of the vessel A through the pipe d into the filters B, B,
I draw off the water from the vessel A by a suitable tap c at the bottom of
the vessel, and recharge the latter with the fluid to be filtered.
In filtering other fluids than resinous or oleaginous matters I avail myself
of a force pump immersed in the fluid to be acted on, or in water, or when it
can be conveniently employed I make use of the direct pressure of the water
from the main of the public supply. As, however, when water is employed it
might commingle with the fluid to be forced through the filters, I adapt inside
the vessel or reservoir A a bag e made of water roof material, somewhat

page_text: larger than the interior capacity of the vessel A. The top of this bag e is
connected with the top of the vessel, as at a (so that the fluid to be filtered
or depurated may be supplied to the bag with facility); the exit pipe d leading
to the filters B also communicates with the bag e, so that as pressure is
exerted on the bag to collapse it, the liquid contained therein may be forced
into the pipe d, and from thence into the filters to be filtered; or I reverse
this arrangement, and allow the liquid to flow into the vessel A outside the
bage, and the water to flow into the flexible bag e, which in that cass is
connected at the bottom with the pipe b, so as to receive the water, whereby
the pressure on the liquid to be filtered is obtained. The bag e must then be
made to communicate with the discharge pipe c, so that the bag may. be
emptied when necessary to recharge the vessel or reservoir A, as will be
readily understood; but when the fluid to be acted on flows direct to the
cylinder the bag is unnecessary. The pipe & serves as a main, communicating
with two, three, or more filters, as shewn in Fig. 1. The construction of
these filters will be best understood by referring to the detached Figures 2, 3,
4, 5, and 7, which are drawn upon an enlarged scale. The capacity of these
filters may be increased or decreased by the use of a greater or less number of
duplicate parts of which they are composed. Fig. 2 is a transverse vertical
section, and Fig. 3 is a horizontal section of one of my improved filters.
These filters I construct of narrow iron boxes or frames of two kinds, C and D,
but both of the same form in plan. One of these boxes is shewn detached in
elevation at Fig. 4. It is a rectangular hollow frame, provided with lugs f,f
to allow of bolts passing through and connecting a series of these frames
together. These boxes or frames Care open at the sides. Alternately with
the boxes Care arranged other frames D, one of which is shewn detached in
elevation at Fig. 7. These frames Dare covered on both sides with filtering
material, held down by wire gauze or other convenient substance, as seen at g,
Fig. 2 both the filtering material and the wire gauze overlap the ed gesof
the box, so that when the boxes C and D are brought together alternately, as
seen in Fig. 2, they will make a secure joint.
The frame 1 is provided with cross or grooved partitions, h, see Fig. 7,
flush with the face of the other box, to afford support to the adjacent filtering
material. As the fluid by the pressure exerted upon it passes through the
filtering strata it flows into the spaces of the box D, and escapes from
apertures i, i, Fig. 2 and Figure 7 into a proper receptacle placed below to
receive it. Each partition box D) has a filter box C on each side, and so on
alternately. The centre box may be cast with gudgeons to admit of a series
of filters being placed on standards, and for convenience in adjusting the

page_text: bolts j, j, which brace the series of filtering surfaces together. The pipe &
supplies the fluid to be filtered to the branch pipes, which conduct it into the
several boxes C, C, Fig. 2, and as the sides of each of the boxes are securely
covered with filtering strata, which by overlapping makes a perfect joint
between the boxes, the fluid must percolate through these strata before it
can escape into the discharge boxes D. Thus the pressure in all the boxes
will be equal, and therefore whatever number of boxes may be employed the
bursting pressure thrown on the bolts j, j, is the same as if only one box were
employed.
.
When it is desirable to depurate or exert any chemical action on the
fluid to be filtered, the boxes C are charged with the material neces-
sary to effect the object, or the same may be previously incorporated with
the fluid prior to its passing to the filter boxes, as before observed. Instead of
making the discharge boxes of iron a block of wood D (Figs. 3 and 5) cut to
the length and breadth of the filtering boxes may be employed. These
blocks are to be grooved or corrugated on each side, as shewn at k, l,
(Fig. 3 and 5) avoiding only those parts which come in contact with the
edge of the filter boxes C, and which parts must be planed true to make a
perfect joint. Over the grooves and overlapping the wood, wire gauze or
other suitable material is fastened to hold the filtering strata in a firm and
secure manner, and also to prevent them from being forced into the grooves in
the wood. From these grooves perforations i, i, (Figs. 2 and 5), through the
edges of the wood allow the filtered fluid to escape. The filter boxes C may
also be constructed of wood of the form described, where the pressure
is not
excessive.
For cleaning the surface of the filtering material without detaching the
parts of the filter I employ knives or scrapers 1, 1, (Figs. 2 and 4), which rest
on the bottom of the filtering boxes C, and are made with sharp edges. They
are the exact width and length of the boxes C, and are constructed to receive
rods m, m, (Figs. 2 and 4), which are passed down through holes in the
upper part of the filter boxes, and screw into their respective scrapers 1, 1.
These scrapers are occasionally drawn up and down over the filtering surfaces,
and thereby remove the deposit collected thereon, which, when it has accu-
mulated to any extent, may be run off through suitable discharge pipes n
(Fig. 4), the supply pipe d being meanwhile closed. The openings for the
insertion of the scrapers 7, 1, must then be closed previously to reopening the
supply pipe d.
In filtering some oily and other fluids where much water is in combi-
nation, it is desirable to make the filter boxes or frames somewhat deeper

page_text: and with one side only open, the other side being closed with a partition_
box, as described. The frames then lay on the lower side and the fluid escapes
from the top, as seen at o, Fig. 6, any convenient number of these filtering
surfaces may then be bolted together.
In filtering or depurating fluids comparatively valueless, and when the
object is to preserve the mechanically soluble portion of the fluid, the
reservoir or vessel A may be dispensed with, and the fluid led at once to the
filter boxes. This may in any case be done, but except in the above I prefer
to use a cylinder, which being provided with a small dome P, (Fig. 1,) above
the level of the liquid is constantly full of air, which moderates by its
elasticity the stroke of the force pump when such is employed.
Having now described my Invention of improvements in filtering and
depurating fluids, and having explained the manner of carrying the same
into effect, I claim as the Invention secured to me by Letters Patent as afore-
said, the mode of and apparatus herein shewn and described for filtering and
depurating fluids.
In witness whereof, I, the said John Marshall, junior, have hereunto
set my hand and seal, this Twenty-first day of October, in the year
of our Lord One thousand eight hundred and fifty-nine.
0
Witness,
J. W. MOFFATT,
66, Chancery Lane.
JOHN MARSHALL, JUN. (L.S.)