Improvements in and connected with the Cleansing of Filters, and Filtering Material employed in the Filtration or Purification of Impure or Foul Liquids.
Year: 1890

page_text: Date of Application, 26th Nov., 1890
Complete Specification Left, 26th Aug., 1891-Accepted, 3rd Oct., 1891
PROVISIONAL, SPECIFICATION.
Improvements in and connected with the Cleansing of Filters, and
Filtering Material employed in the Filtration or Purification of
Impure or Foul Liquids.
We, CHARLES HENRY BELOE, Civil Engineer, and FRANK CANDY, Manu-
facturer, both of 7, Victoria Street, London, S.W., do hereby declare the nature
of this invention to be as follows
The kind of filters to which this invention has special reference are those used
for filtering liquids in comparatively large quantities, such as are used in water
works, sewage disposal works, and in connection with or for many kinds of manu-
factures, and the like, and it relates particularly amongst other things to the
system or method of cleansing filters set forth in a former Specification of Letters
Patent No. 8088 of 1889 granted jointly to us.
In the said former Patent a method is set out in one portion of the Specification
according to which the filtered effluent of one filter is caused to pass through the
filtering material of another filter and cleanse such filter.
We have found that by so working such filters the cleansing effect would not be
sufficiently, rapidly performed in many cases; and we have also found that the
removal of the scum-and dirt-from the upper layer or layers of sand of filter
beds by the methods heretofore in practice, is not so rapid in its action or so
effectual as, in many cases, is desired to the end of rendering these processes more
rapid and more effectual, the present invention is directed. And a further object
of the invention is to wash or cleanse the upper layer or layers of sand of filter
beds with greater expedition than is obtained by the present system, and at
less cost.
According to the present invention the purified effluent of a plurality of the
filters of a system of filter beds is conveyed to, and caused to pass through, the
filtering material of a single filter and cleanse such material; the effect of
the combined effluents of the plurality of filters upon the one being, that the
passage of water through it partakes of the nature of a flushing action, which it did
not when the effluent of one only was used, as set forth in our former Specification;
that is to say, in that system wherein the effluent of one filter bed only was employed
to cleanse another filter, the flow of the cleansing fluid would in many cases be too
slow, and not of a flushing nature.
Regarding the feature of removal of the scum and dirt from the upper layer or
layers of the sand of filters, according to the present invention, we cause the surface
of the sand to be flushed with a considerable body of liquid, say unfiltered liquid,
such liquid being distributed from suitable conduits from both sides of the filter,
and flowing towards a central washout trough. Or the converse mode of flushing
may be employed, that is to say the flushing liquid may be distributed from a
central trough to side washout troughs; or again, according to another modification.
a series of washing-liquid troughs and washout troughs may be employed: the
surface of the sand in all cases having such an incline and fall as to cause the
cleansing liquid to flow at a sufficiently rapid rate to effect the desired object ;* and *.
this may be accelerated by raking the surface of the sand. The washing liquid and
the scum and dirt removed by it are led away to any suitable point and disposed of
in any convenient or desired way.
By this method or means, the scum and dirt lying upon the surface of the sand
of filter beds are rapidly and effectually washed off and removed.
In one arrangement of filter bed which we may employ, the washing liquid may be

page_text: fed to the washing-liquid trough or troughs from a supply trough at a higher level,
the liquid being led to the supply trough from an inlet channel or conduit.
The washing of the top layer of sand of filter beds is according to the present
invention, effected in the following manner: -In lieu of removing the sand from
the filters altogether and carrying it away as commonly practised, and washing it
by machinery or otherwise at the place to which it is removed, and then bringing it
back to the filter bed, we, according to this invention wash it in or on the bed itself,
by throwing it into a conduit or vessel on the filter, down which water is caused to
pass, the sand and liquid being delivered into a washing and settling box. After
the sand has been so washed it is relaid in the filter.
In one arrangement of parts by which this mode of sand washing is carried out,
the washing box is on the filter bed, and in communication with the washout trough,
and a trough arranged at a suitable incline and adapted to convey water from the
supply trough of the filter bed to the box. In action, as the water flows down
the inclined trough the sand is thrown into it by those carrying on the process.
The resulting action is that the sand and water are discharged, thoroughly mixed,
into the sand box wherein the agitation, due to the velocity of the flow into the
box, causes the sand to be thoroughly washed, and to subsequently settle at the
bottom of same, the box being divided into two or more portions by a partition or
partitions to render the settling of the sand complete, such portions being in
communication with each other by apertures provided in the divisions at suitable
places and levels. The water passes out of the box into the washout trough away
to the outflow, the clean sand remaining in the box ready for use.
It is to be understood that the several improvements herein described are not
confined to the particular mode or means herein specified by which they are carried
out, as such modes or means will necessarily be carried out in various modified or
different ways to suit the varying conditions or circumstances of the different
applications of the invention; nor is the invention confined to the particular forms
and combinations of the apparatus or parts specified.
Dated this 25th day of November 1890.
CHEESBROUGH & ROYSTON,
15, Water Street, Liverpool, Applicants' Patent Agents.
COMPLETE
SPECIFICATION.
Improvements in and connected with the Cleansing of Filters, and
Filtering Material employed in the Filtration or Purification of
Impure or Foul Liquids.
We, CHARLES HENRY BELOE, Civil Engineer, and FRANK CANDY, Manu-
facturer, of 7, Victoria Street, London, 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:
The kind of filters to which this invention has special reference are those used for
filtering liquids in comparatively large quantities, such as are used in waterworks,
sewage disposal works, and in connection with or for many kinds of manufactures,
and the like, and it relates particularly amongst other things to the system or
method of cleansing filters set forth in a former Specification of Letters Patent
No. 8088 of 1889 granted jointly to us.
In one portion of the said former Specification a method is set out according to
which the filtered effluent of one filter is caused to pass through the filtering
material of another filter and cleanse such filter.
We have found that by so working such filters, the cleansing effect would not be
sufficiently rapidly performed in many cases; and we have also found that the
removal of the scum-and dirt-from the upper layer or layers of sand of filter
beds by the methods heretofore in practice, is not so rapid in its action or so

page_text: effectual as, in many cases, is desired; to the end of rendering these processes more
rapid and more effectual, the present invention is directed. And a further object
of the invention is to wash or cleanse the upper layer or layers of sand of filter
beds with greater expedition than is obtained by the present system, and at
less cost.
According to the present invention, the purified effluent of a plurality of the
filters, of a system of filter beds is conveyed to, and caused to pass through, the
filtering material of a single filter and cleanse such material; the effect of
the combined effluents of the plurality of filters upon the one being, that the passage
of water through it partakes of the nature of a flushing action, which it did not
when the effluent of one only was used, as set forth in our former Specification;
that is to say, in that system wherein the effluent of one filter bed only was employed
to cleanse another filter, the flow of the cleansing fluid would in many cases be too
slow and not of a flushing nature.
Regarding the feature of removal of the scum and dirt from the upper layer or
layers of the sand of filters, according to the present invention, we cause the surface
of the sand to be flushed with a considerable body of liquid, say unfiltered liquid,
such liquid being distributed from suitable conduits from both sides of the filter,
and flowing towards a central washout trough. Or the converse mode of flushing
may be employed, that is to say, the flushing liquid may be distributed from a
central trough to side washout troughs; or again, according to another modification,
a series of washing-liquid and washout troughs may be employed; the surface of
the sand in all cases having such an incline and fall as to cause the cleansing liquid
to flow at a sufficiently rapid rate to effect the desired object; and this may be
accelerated by raking the surface of the sand. The washing liquid and the scum
and dirt removed by it are led away to any suitable point and disposed of in any
convenient or desired way.
By this method or means, the scum or dirt lying upon the surface of the sand of
filter beds are rapidly and effectually washed off and removed.
In one arrangement of filter bed which we may employ the washing liquid may
be fed to the washing-liquid trough or troughs from a supply trough at a higher
level, the liquid being led to the supply trough from an inlet channel or conduit.
The washing of the top layer of sand of filter beds is, according to the present
invention, effected in the following manner :-In lieu of removing the sand from
the filters altogether and carrying it away as commonly practised, and washing it
by machinery or otherwise at the place to which it is removed, and then bringing
it back to the filter bed, we, according to this invention wash it in or on the bed
itself, by throwing it into a conduit or vessel on the filter, down which water is
caused to pass, and sand and liquid being delivered into a washing and settling
box. After the sand has been so washed it is relaid in the filter.
In one arrangement of parts by which this mode of sand washing is carried out,
the washing box is on the filter bed, and in communication with the washout trough,
and a trough arranged at a suitable incline and adapted to convey water from the
supply trough of the filter bed to the box. In action, as the water flows down
the inclined trough the sand is thrown into it by those carrying on the process. The
resulting action is that the sand and water are discharged, thoroughly mixed, into
the sand box wherein the agitation, due to the velocity of the flow into the box,
causes the sand to be thoroughly washed and to subsequently settle at the bottom
of same, the box being divided into two or more portions by a partition or partitions
to render the settling of the sand complete, such portions being in communication
with each other by apertures provided in the divisions at suitable places and levels.
The water passes out of the box into the washout trough away to the outflow, the
clear sand remaining in the box ready for use.
The above description sets forth, generally, the nature, object, and purposes of
our invention, but to make it more clear, we will now proceed to describe it with
the aid of the drawings accompanying this Specification, and forming a part thereof.
The drawings, together with the following description of them, illustrate and set

page_text: forth examples of plant, connected with. the "filtration or purification of impure
or foul liquids, specially designed to carry out the improvements the nature of which
has been above generally explained ; while the points of novelty of our invention,
which we desire to cover by these Letters Patent, will be specifically pointed out
in the claiming clauses concluding the Specification.
Figure 1 is a plan shewing a set of filters and' their various inlet and outlet
passages or conduits, provided with and adapted to operate according to the improve-
ments herein specified.
Figure 2 is a cross sectional elevation taken at the line A. A. Figure 1, and
looking towards the inlets of the filter.
Figure 3 is a sectional elevation taken at the line B B Figure 1.
Figure 4 is a longitudinal sectional elevation, taken at the line C C Figure 1.
Figure 5 is a sectional elevation of means employed in carrying out the improve-
ment under this invention connected with the washing of sand of filter beds.
Referring now to the drawings, a designates generally the beds, which it may be
assumed are substantially of the nature as specified in our former Specification
referred to, and having an upper layer of sand; bare the brickwork walls con-
stituting the containing walls for the filtering materials and various conduits; c is
the inlet conduit by which the liquid to be filtered is supplied to the 'different beds ;
care branches from the conduit c for supplying the different beds, and having
paddles by which said supply is admitted, shut off, or controlled as desired;
3 are paddles in the main conduit c; d is a conduit disposed at the end of each
filter bed a, and at a considerable elevation above the surface of the filtering
material, and into which the liquid from c¹ is supplied; e is an inclined trough,
supported at one end close under the supply trough d, the other end resting upon
the surface of the filter bed; d' is a spout on the side of the trough d, and d² is a
paddle by which the liquid supplied to the trough e is controlled; is the wash-out
trough arranged in the centre of the bed a and upon which, in the arrangement of
parts shewn, the lower end of the trough e rests; g are the troughs, disposed one on
either side of the filter beds, to which the water used to wash the surface of the
sand thereof is supplied and from which it flows on to and over the said surface ;
hare pipes fixed in the bottom of the trough d and discharging into the washing
troughs are plugs by which the supply of liquid from d to the pipes h is given
or shut off; i is a pipe similar to h but discharging into the washing-out trough f,
and having also a plug similar to h¹ by the removal of which the trough can be
flushed with water from d at any time; k are pits into which the liquid discharged
from the surface of the filter, by way of the wash-out trough f, is discharged; kare
paddles by which the communication between the filters and said pits is made or
cut off as desired; is the pipe which is called the wash-out pipe, by which the
liquids discharged into the pits k are carried away.
With reference now mainly to the arrangement of parts by which the cleansing
of the filters in the manner herein specified is carried out, the bottom of each filter
bed is provided with covered channels into which the filtered liquid flows when
filtering, and by way of one of which such liquid passes through an effluent pipe.
These covered channels we also adapt to serve as the conduit by which the purified
effluent of a plurality of filters may be distributed throughout the one filter to be
cleansed. designates the covered ways, and drains communicating between
such ways and the whole bottom surface of the bed. One of the covered ways n of
each filter bed is connected with the effluent pipe, which is designated o.
In the arrangement shewn in Figure 1, o' are gutters leading into the main o
within the chamber or pit p, and on the main, in this pit, is provided a valve g, by
closing which, and stopping the supply of liquid to the bed to be cleansed, the
cleansing operation of the different filter beds is controlled. There are, however,
paddles provided on the mouth of the pipes o, which connect the covered ways n
with the pit p, but these are not used in the filter cleansing operations, and merely
serve as a means of regulating the rate of discharge of effluent from any one filter
or filters, and consequently the rate of filtration. The process of cleansing a bed
02

page_text: by, say, the effluent of the other three beds of the arrangement shewn, is effected by
closing the valve 9 of the effluent pipe o, when the water will rise in the well P,
will flow through a pipe o into the covered channels n and drains n' of said bed,
and up through the filtering material therein-the supply of liquid from the inlet
main c to that bed of course having been previously stopped and the paddle k¹
opened. The water having passed up through the filtering material in the filter
then flows into the wash-out gutter f, then into the pit k connected with it, and
away by way of the wash-out pipe l.
The effect of the product of these three filters being passed through one filter is,
as above stated, that the action on the filtering material partakes of the nature of a
flushing action, and in consequence the material is thoroughly cleansed.
The action with respect to the removal from the surface of the filters of scum and
dirt preferably takes place at the same time as the cleansing operation, and is as
follows:-
The paddle being open, and d² closed, and the plugs ¹ removed, water from
the inlet channel e' flows into the channel d, and from thence by way of the pipes h
into the washing troughs g at the sides of the filters. The water overflowing g, g,
in comparatively large volume, pours down over the whole surface of the beds
towards the wash-out trough, and such surface being of a considerable incline,
such as shewn, the scum and dirt is effectually removed, and rapidly. However, to
accelerate the action, the surface of the sand may be raked at the same time.
The scum and dirt and water which find their way into the wash-out trough flow
into the tank k, and away into the pipe 7. In lieu of washing the whole surface of
a bed at once it may be done in sections by having several flaps in the sides of the
trough g which may be lowered one at a time.
With respect to that portion of the invention having reference to the washing of
sand of filter beds, designates the box herein above referred to, used under this
invention. It is placed in the bed in the position shewn in dotted lines in Figure 1,
and as in Figure 5, with the inclined trough e resting upon one end, the other, the
outlet end, standing over the wash-out trough f. In the box is a partitions having
holes at each side, and by which the settling of the sand in the box after it is
washed, is effected. In the operation of this portion of the invention, water is
allowed to flow down the trough e from the trough d, and sand is thrown into the
trough by those carrying on the operation. The action is, that the sand and water are
discharged into the sand box thoroughly mixed, and agitation taking place due to
the velocity of the flow into the box, the sand is thoroughly washed. The sand
mainly settles at the bottom of the box in the front portion thereof, and some in the
portion behind the partitions, whilst the water flows away from the box by the
aperture at t in the end thereof, into the wash-out trough f. Whatever small
proportion of sand passes out of the box is caught in the pits k. As the sand
settles in the box it is removed and relaid in the filter in the position required. It
will then be seen, that in this sand washing process, all that is to be done is to
throw the sand into the trough e, take it out of the box r, and re-lay it in the
filter.
Having now fully described and illustrated by examples the nature of our said
invention, and in what manner the same is to be performed, we declare that what
we claim in respect of the herein described invention is :-
1. In systems for the purification or filtration of impure or foul liquids, the
herein described improvements connected with the cleansing of the filters employed
therein, consisting in causing the combined filtered effluents coming from a plurality
of such filters to pass up through the filtering material of one other filter of such
system and cleanse it.
2. A filtering plant for use in the filtration and purification of impure or foul
liquid, comprising a plurality of filters discharging into a common main having a
valve thereon, and so arranged, that by the closing of said valve, the combined

page_text: filtered effluents of two or, more of such filters will be caused to pass upwards.
through the filtering material of another filter bed.
3. In systems for the filtration or purification of impure or foul liquid, effecting.
the removal, of scum and dirt from the surface of the sand or material employed
therein, by causing a flush of water or. liquid to flow over the surface down and
towards a receiving and wash-out trough, and carrying off said dirt and scum and .|
water thereby, substantially.as herein set forth.
4. In filters for the filtration of impure or foul liquids, a trough or conduit.
therein disposed above the level of the filtering material and adapted to discharge
into other conduits in or on said filter at a lower level from which water. is caused
to flow over the surface towards a wash-out trough or conduit, whereby the scum
and dirt is washed from off the surface; substantially as herein set forth.
5. Effecting the washing of the sand of filters on the filter beds themselves, .by.
bringing water from the ordinary supply conduits of the beds and causing it to mix
with the sand which is introduced or thrown into a conduit or chamber through
which said water is flowing; and depositing the said sand subsequently; substan-
tially as set forth.
6. In a filter bed, the arrangement and combination of parts for washing the
sand of and within said filter bed, comprising the trough e, and the box r, disposed
within the bed, and adapted to operate as set forth with reference to the drawings..
7. The arrangement and construction of filters or filtering apparatus set forth
with reference to Figures 1, 2 and 3, comprising the beds a disposed on either side
on the effluent pipe o and wash-out pipe l, and a supply or inlet conduit c, arranged
at the other or outside end of said beds.
8. The herein described means of cleansing of the wash-out trough f of a filter
bed, consisting of introducing a flush of water from an upper trough (such as d) or
equivalent supply by a pipe, such as i, arranged and adapted to operate as specified
and shewn.
Dated this 95th day of August 1891
CHEESBROUGH & ROYSTON,
15, Water Street, Liverpool, Applicants' Patent Agents.