IMPROVEMENTS IN FILTERING WATER, AND IN THE APPARATUS EMPLOYED THEREIN
Year: 1876

page_text: LETTERS PATENT to John Henderson Porter, of Lavenham, in the County of
Suffolk, Civil Engineer, for the Invention of "IMPROVEMENTS IN FILTERING
WATER, AND IN THE APPARATUS EMPLOYED THEREIN."
Sealed the 16th June 1876, and dated the 21st April 1876.
PROVISIONAL SPECIFICATION left by the said John Henderson Porter at
the Office of the Commissioners of Patents on the 21st April 1876.
"
JOHN HENDERSON PORTER, of Lavenham, in the County of Suffolk, Civil Engineer,
"IMPROVEMENTS IN FILTERING WATER, AND IN THE APPARATUS EMPLOYED THEREIN.'
My Invention relates to the filtration of water in course of treatment by what
is known as Clarke's process" for softening and purifying water, and has for its
object facilitating, particularly for manufacturing and industrial purposes, the use of
the said process.
"
The general adoption of the said process has hitherto been obstructed by the
necessity of very capacious tanks or vessels for the settling out of the precipitate
of carbonate of lime, and for the storage for supply of the water when cleared.
The formation of this precipitate of carbonate of lime results as is well known
from the introduction of a clear solution of lime water into the hard water to be
softened and by the rapid conversion of the soluble bicarbonate of lime to which
the "hardness" is commonly and mainly due, into insoluble carbonate of lime or
chalk, producing a milky appearance in the water thus treated until after the lapse
of some hours the minute particles of chalk or carbonate of lime have entirely
settled down.
Now my Invention consists essentially in the utilization of the precipitate of
carbonate of lime resulting from the said process as the medium of filtration in
apparatus constructed in the manner herein-after described.
In carrying out my Invention according to one modification the filtering apparatus
is composed of a series of compartments, each of which consists of a circular frame
with a panel of bars forming a grating, on each side of this panel of bars or grating
there is placed a circular plate of perforated metal or a panel of wire gauze fitting
into a suitable recess, and on the outer side of each of such perforated plates or
wire gauze panels there is fitted a circular straining cloth attached to a light iron
[Price 6d.]

page_text: ring or hoop, and fitted also into a recess provided for it. The frame of the com-
partments itself projects somewhat beyond the planes of these straining cloths so
that when the series of compartments are pressed up together by one or more
powerful screws acting at the end of the apparatus narrow intermediate spaces are
left between the straining cloths of each pair of adjoining "compartment." An
oblong opening is provided through the upper part of each frame which is then
enlarged by additional metal at the top, which openings when the several com-
partments are pressed up tightly together form one common channel or tube from
which suitable openings are provided into the several intermediate spaces above
referred to. In the lower part of each compartment and in the intervals between
the bars of the grating small openings are provided into a tubular way or pipe
formed in the frame of the compartments enlarged at this part. This pipe extends
outwards on either side, and at one end is provided with a flange for the attachment
of a cock and at the other end with a screw plug by the removal of which a wire
can be introduced for cleansing it.
In operating with this apparatus the cloudy or milky water is introduced by
gravitation from the tanks or vessels in which the softening process is performed
and which I arrange at any convenient height above the filters into the common
channel formed by the openings through the upper parts of the frames of the said
compartments, and thence into the intermediate spaces existing between each pair
of straining cloths arranged as aforesaid. The cloudy or milky water is first
admitted very slowly until the interstices and surfaces of the cloths have become
sufficiently coated with a deposit of the precipitate of carbonate of lime_to
effectually filter the succeeding water from the particles of chalk in suspension. The
water thus freed from the carbonate of lime passes through the perforated plates
or wire gauze into the spaces between the vertical bars, and thence through the
small openings at the bottom into the tubular way or pipe below, when the inter-
stices and surfaces of the cloths have become so coated and filled with the precipitate
of carbonate of lime that perfectly clear water only issues from the filter, I gradually
increase the supply of water to be filtered, for as the coating of precipitate increases
in thickness upon the straining cloths so may the quantity or the pressure of water
be increased; when the coating of precipitate has increased to such a degree as
materially to lessen the quantity of filtered water furnished by the filter within a
given time the several compartments are separated by relaxing the pressure of the
end screw, and by means of a stick or blade or any convenient tool the superfluous
accumulation of the carbonate of lime is removed from the several straining cloths,
a sufficient coating being left for the purpose of filtration, the series of compartiments
is closed up again and the filtration is resumed.
According to another modification the panel of each compartment, in lieu of
being constructed in the form of a grating, is made solid, and has small ribs and
grooves forming channels, by which the liquid having passed through the straining
cloths and perforated plates is conducted to the pipe below. In this case the
straining cloths are not fitted within the frames of the compartments, but extend
beyond them on all sides. Between each pair of compartments and straining cloths
there is interposed an open frame with handles, which forms a circular intermediate
space for the reception of the cloudy or milky water to be filtered.
The straining
cloths have holes made in them corresponding to those provided through the com-
partments and intermediate frames for the passage of such water, the said holes
forming, when the several compartments are pressed up together, one tube or
channel common to all, which may be made in the corner of the frame and com-
partment, or in the centre of the panel, or in any other suitable position, as described
in the case of the apparatus constructed under the first modification, when the
quantity of filtered water discharged within a given time is considerably diminished.
I open the filter and remove the surplus accumulation of the precipirate of carbonate
of lime.
The apparatus may be further modified in various ways in carrying out my
Invention whilst retaining the same principle; as, for example, the apparatus may

page_text: be constructed in a similar manner to that described in the Specification to Letters
Patent granted to Conrad William Finzel, William Needham, and John Barton, the
8th May 1856, No. 1083; also in the Specification to Letters Patent granted to
William Needham and James Kite, 14 July 1853, No. 1669, and 1st Dec. 1855,
No. 2709; and to James Kite, 15 June 1854, No. 1300; also to William Needham
and James Kite, 31 May 1856, No. 1288.
The mechanical details by which the series of compartments are combined may
also be greatly modified, as also those by which the water to be filtered is intro-
duced to or withdrawn from the said compartments.
For the latter purpose it may be found sufficient to provide one common channel
(as for the admission of the water) in lieu of several small independent outlets
employed in some of the modifications herein-before described.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by the
said John Henderson Porter in the Great Seal Patent Office on the 7th
October 1876.
JOHN HENDERSON PORTER, of Lavenham, in the County of Suffolk, Civil
Engineer. "IMPROVEMENTS IN FILTERING WATER AND IN APPARATUS EMPLOYED
THEREIN."
My said Invention relates to the filtration of water in course of treatment by
what is known as "
Clarke's process" for softening (and purifying) water, and has
for its object facilitating particularly for manufacturing and industrial purposes the
use of the said process.
The general adoption of the said process his hitherto obstructed by the neces-
sity for very capacious tanks or vessels for the settling out of the precipitate of
carbonate of lime and for the storage for supply of the water when cleared. The
formation of this precipitate of carbonate of lime results, as is well known, from the
introduction of a clear solution of lime water into the hard water to be softened,
and from the rapid conversion of the soluble bicarbonate of lime to which the
hardness is commonly and mainly due into insoluable carbonate of lime or chalk,
whereby a milky appearance is produced in the water thus treated, until after the
lapse of some hours the minute particles of chalk or carbonate of lime have entirely
settled down.
Now my Invention consists essentially in the utilization of the precipitate of
carbonate of lime resulting from the said process as the medium of filtration in
apparatus constructed in the manner herein-after described, reference being had to
the Sheet of Drawings hereunto annexed.
Figure 1 of the accompanying Drawings represents a side elevation partly in
section of one modification of apparatus employed in carrying out my Inven-
tion. Figure 2 is an end elevation of the same; and Figures 3 and 4 are detail
views to be herein-after referred to.
Figure 5 represents a side elevation of another modification of apparatus employed
in carrying out my Invention. Figure 6 is an end elevation of the same; and
Figures 7, 8, and 9, are detail views to be herein-after referred to. Similar letters
indicate like parts in all the Figures.
Referring to the arrangement illustrated by Figures 1, 2, 3, and 4, the filtering
apparatus is composed of a series of compartments A, A, each of which consist of
a circular frame a, with a panel of bars forming a grating b, as shewn clearly in
elevation and section in the detail views, Figures 3 and 4 respectively. On
each side of this panel of bars or grating 6 there is placed a circular plate of
perforated metal or a panel of wire gauze c, fitting into a suitable recess, and on
the outer side of each of such perforated plates or wire gauze panels c there is fitted
a circular "straining cloth" d, attached to a light iron ring or hoop, and fitted also
into a recess provided for it. The frame a of the compartments itself projects

page_text: somewhat beyond the planes of the straining cloths d, so that when the whole of
the compartments A, A, forming the series are pressed up together by the aid of a
powerful screw B, or of two or more of such screws acting at the end of the
apparatus, narrow intermediate spaces e are left between the straining cloths d
of each pair of adjoining compartments. An oblong opening fis provided through
the upper part of each frame which is there enlarged by additional metal at the
top, which openings when the several compartments are pressed up tightly together
form one common channel or tube, from which suitable openings g are provided
into the several intermediate spaces e. In the lower part of each compartment,
and in the intervals between the bars of the grating b, small openings are
provided into a tubular way or pipe i formed in the frame of the compartments
enlarged at this part. This pipe extends outwards on either side and at one end is
provided with a flange for the attachment of a cock l, and at the other end with
a screw plug m, by the removal of which a wire can be introduced for cleaning it.
The series of compartiments may be supported in any suitable manner. In the
example shewn in my Drawings they are represented as carried by longitudinal rods
B¹, B, mounted in standards C, C, the frames a of the intermediate compartments A
being provided with lugs n which rest on the rods B', B¹, whilst the frames a of the
end compartments A¹ as also the closing ends A, A, which may be cast in one there-
with are formed with projecting eyes n', n', through which the rods B¹, B¹, pass.
Grooves o are provided in one side of each frame for the reception of packing, in order
to prevent leakage when the whole of the compartments of the series are in close
juxtaposition.
In operating with this apparatus the cloudy or milky water is introduced at one
end (say for example at o¹) by gravitation from the tanks or vessels in which the
softening process is performed, and which I arrange at any convenient height above
the filters into the common channel formed by the openings f through the upper
parts of the frames a of the same compartments, and thence into the intermediate
spaces e, existing between each pair of straining cloths d arranged as aforesaid.
The cloudy or milky water is first admitted very slowly until the interstices and
surfaces of the cloths & have become sufficiently coated with a deposit of the pre-
cipitate of carbonate of lime to effectually filter the succeeding water from the
particles of chalk in suspension. The water thus freed from the carbonate of lime
passes through the perforated plates or wire gauze c into the spaces ¹, between
the vertical bars b, and thence through the small openings h at the bottom into
the tubular way or pipe i below, whence it is withdrawn through the cock Z.
When the interstices and surfaces of the cloths have become so coated and filled
with the precipitate of carbonate of lime that perfectly clear water only issues
from the filter, I gradually increase the supply of water to be filtered, for as the
coating of precipitate increases in thickness upon the straining cloths so may the
quantity or the pressure of water be increased. When the coating of precipitate
has increased to such a degree as materially to lessen the quantity of filtered water
furnished by the filter within a given time, the several compartments are separated
by relaxing the pressure of the end screw B, and the straining cloths d are either
taken out and replaced by others, or the superfluous accumulation of the carbonate
of lime is removed from the cloths by means of a stick or blade, or any convenient
toof, a sufficient coating being left for the purpose of filtration, and the series of
compartments is then closed up again and the filtration is resumed.
In the modification illustrated by Figures 5, 6, 7, 8, and 9 of my Drawings, the
panel of each compartment, in lieu of being constructed in the form of a grating,
is made solid, and has small ribs and grooves forming channels 61, as shewn in
Figures 7 and 8, which may be arranged either radially and annularly, as in the
example illustrated, or otherwise, by which channels the liquid having passed
through the straining cloths d, and perforated plates or wire gauze panels c, is
conducted to the pipe i below, and escapes as before. In this case the straining
cloths & are not fitted within the frames a of the compartments, but extend beyond
them on all sides.

page_text: Between each pair of compartments A, A, and straining cloths d, d, there is inter-
posed an open frame D (shewn detached in Figure 9), having handles p to facilitate
its removable, which frame forms a circular intermidiate space D¹ for the reception of
the cloudy or milky water to be filtered, and which is conducted thereunto from
the channel through openings g. The straining cloths d have holes made in
them, corresponding to those f provided through the frames a of the compartments
A and the intermidiate frames D, for the passage of such water, the said holes
forming, when the several compartments are pressed up together by the act of ope-
rating the screws B, B, by the aid of the hand wheel E and gearing F, or other-
wise, one tube or channel common to all, which may be made either in the corner of
the frame and compartment, as shewn, or in the centre of the panel b, or in any
other suitable position.
When during the operation of filtering the quantity of filtered water discharged
within a given time is considerably diminished I open the filter and remove the
surplus accumulation of precipitate of carbonate of lime, as herein-before described
with reference to the first modification, after which I reclose the filter, and resume
the operation as before.
The apparatus may be further modified in various ways in carrying out my.
Invention, whilst retaining the same principle. For example, the apparatus may
be constructed in a similar manner to that described in the Specification to Letters
Patent granted to Conrad William Finzel, William Needham, and John Barton, the
8th May 1856, No. 1083; also in the Specification to Letters Patent granted to
William Needham and James Kite, 14th July 1853, No. 1669, and in their Pro-
visional Specification deposited 1st December 1855, No. 2709; also in the Specifi-
cation to Letters Patent granted to James Kite, 15th June 1854, No. 1300; also to
William Needham and James Kite, the 31st May 1856, No. 1288.
The mechanical details by which the compartments of the series are combined
may also be greatly modified, as also those by which the water to be filtered is
introduced to or withdrawn from the said compartments. For the latter purposes
it may be found sufficient to provide one common channel, as for the admission
of the water, in lieu of several small independent outlet pipes employed in some of
the modifications herein-before described.
Having now described and particularly ascertained the nature of my said Inven-
tion, and the manner in which the same is or may be used or carried into effect, I
would observe in conclusion that I do not claim, as forming any part of my Inven-
tion, the apparatus considered separately from the particular purpose to which I
apply them; but what I consider to be novel and original, and therefore claim as
the Invention secured to me by the herein-before in part recited Letters Patent,
is, filtering water in course of treatment by what is known as Clarke's process,
by the utilization of the precipitate of carbonate of lime resulting from the said
process as the medium of filtration in apparatus constructed substantially in the
manner herein-before described.
In witness whereof, I, the said John Henderson Porter, have to this my
Specification set my hand and seal, this Second day of October, One
thousand eight hundred and seventy-six
JOHN H. PORTER. (L.S.)