Improvements, in Filters and Arrangements and Apparatus or Plant connected therewith.
Year: 1897

page_text: Date of Application, 13th Feb., 1897
Complete Specification Left, 15th Nov., 1897-Accepted, 18th Dec., 1897
PROVISIONAL SPECIFICATION.
Improvements, in Filters and Arrangements and Apparatus or Plant
connected therewith.
We, FRANK CANDY of No 56 Nightingale Lane Balham in the County of Surrey
Manufacturer and THE INTERNATIONAL WATER AND SEWAGE PURIFICATION COMPANY
LIMITED of Westminster Chambers No 7 Victoria Street in the City of Westminster
Contractors for the purification of water and sewage do hereby declare the nature of
this invention to be as follows:-
This invention consists of improvements in filters and arrangements for permitting
of escape or separation of air and gas from liquids passing to filters and arrangements
for causing dispersion or diffusion of cleansing liquid within the beds of filters having
provision for cleansing by reverse flow of liquid through them and apparatus or plant
whereby the cleansing of filters is caused to take place automatically when requisite.
The filters to which the improvements herein first referred to exclusively relate are
such as are designed for acting in an upward direction and are provided with arrange-
ments for cleansing of the filtering medium by downward passage of filtered liquid
through the filter beds and the said improvements consist in forming the filter bed
of smaller sectional area at the lower part than at the upper part or in placing the
material of which the said bed is composed within a receptacle of smaller sectional
area at the lower part than at the upper part the object being to cause the cleansing
liquid to act more forcibly in the part of the bed where the principal deposit of
matter separated from liquid being filtered takes place than at other parts of the
said bed. In orderto prevent disturbance of the filtering material by passage of liquid
through the filter bed a layer of pebbles or fragments of matter of high specific
gravity such as manganese or heavy spar is placed on the uppermost layer or on it is
placed a perforated plate connected to a screwed rod by turning which in one or other
direction the said plate may be readily raised and lowered according to requirements.
The arrangements for permitting of escape or separation of air and gas from liquids
passing to filters are applicable to upwardly acting filters and consist in a chainber
situated between the filter and the conduit conveying the liquid to be filtered and
communicating both with the said conduit and with the inlet of the filter which chamber
has an opening or openings in its upper part at a higher level than that of the liquid
to be filtered or has connected to its upper part a pipe or pipes opening above the
level of the liquid to be filtered. By means of this arrangement air.or gas contained
in the liquid passing through the supply conduit, is allowed to escape or separate
from the said liquid before it enters the filter the said air or gas rising in the said
chamber and escaping from the surface of the liquid therein and passing from the
said chamber by, the opening or openings or pipe or pipes at the upper part thereof.
The said chamber, maybe conveniently constructed in the form of a casing
surrounding a receptacle containing the filter bed or surrounding the lower part of
such receptacle but the said chamber may be arranged apart from the filter receptacle
and in connection with the supply conduit only.
The arrangements for causing dispersion or diffusion of cleansing liquid within filter
beds consist of conduits communicating between the supply of cleansing liquid and

page_text: the said beds and adapted to conduct the said liquid into and deliver it within the
interior of the bed of filtering material the inlet mouths of which conduits are by
preference provided with valves so arranged as to permit free entry thereto of the
cleansing liquid and to prevent passage therethrough of liquid being filtered. The
said conduits may consist of perforated annular pipes situated within the part of
the filter bed from which filtered liquid passes and connected with branch pipes
communicating with a receptacle in which the filtered liquid collects the said branch
pipes having buoyant valves so arranged within them as to automatically close the
said pipes against the passage of liquid passing in the filtering direction and leave
them open for the passage of liquid passing in the cleansing direction. The said
annular pipes may be furnished with branch discharge pipes projecting in various
directions into the bed of filtering medium for producing dispersion or diffusion of
the cleansing liquid within the said bed.
The improvements in apparatus or plant whereby the cleansing of filters is caused
to take place automatically when requisite are especially applicable to upwardly
acting filters and are hereinafter described with reference to such filters. The main
object of the said improvements is to avoid the waste or extravagent use of filtered
liquid which is unavoidable in the case of such apparatus or plant as has heretofore
been proposed for the said purpose.
According to the said improvements provision is made for collection and retension of
a considerable quantity of filtered liquid above the level of the filter bed during the
filtering action and the pipe for supply of liquid to the filter and a pipe (hereinafter
termed the escape pipe) by which cleansing liquid passes from the filter are
furnished with valves or cocks so connected with a float (hereinafter termed the
valve float) arranged within a suitable vessel that the supply to the filter is cut off
and the escape pipe is opened by rising of the said float which is caused by inflow
of liquid to the receptacle in which it is placed and into which a portion of the
supply of unfiltered liquid passes directly or indirectly when the action of the
filter is obstructed by accumulation in the filter bed of matter separated thereby
from the liquid being filtered. To provide for automatic outflow of liquid from the
receptacle containing the float according to requirements it is furnished with a
weighted valve so connected to a float supported by the filtered liquid accumulat-
ing above the level of the filter bed that descent of the said float causes the opening
of the said valve and ascent of the said float permits of the said valve being closed
by the action of its weight. By means of the said apparatus the quantity of filtered
liquid which while the filter bed is in action collects and is retained above the level
thereof is permitted to descend through the said bed by the opening of the valve in
the escape pipe through the medium of the valve float the actuation of which float
is produced by inflow to the vessel containing it of a portion of the supply of unfiltered
liquid the passage of which into the said vessel is consequent on clogging or obstruc-
tion to the action of the filter bed by accumulation therein of matter as before
stated. After the filter bed has been cleansed by descent through it of the aforesaid
quantity of filtered liquid the consequent descent of the float supported by the said
liquid causes the outlet valve of the float box to be open whereby escape of liquid
from the said box is permitted the effect being descent of the valve float and closing
of the valve in the escape pipe and opening of the valve in the supply pipe. The
filtering action is thus reestablished and continues until a further accumulation of
matter in the filter bed causes repetition of the automatically governed action of the
cleansing apparatus as bereinbefore described.
D
1

page_text: Improvements in Filters and Arrangements and Apparatus or Plant
connected therewith.
We FRANK CANDY of No. 56 Nightingale Lane Balham in the County of Surrey
Manufacturer and THE INTERNATIONAL WATER AND SEWAGE PURIFICATION COMPANY
LIMITED of Westminster Chambers No. 7 Victoria Street in the City of Westminster
Contractors for the purification of water and sewage 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 consists of improvements in filters and arrangements for permitting
of escape or separation of air and gas from liquids passing to filters and arrangements
for causing dispersion or diffusion of cleansing liquids within the beds of filters
having provision for cleansing by reverse flow of liquid through them and apparatus
or plant whereby the cleansing of filters is caused to take place automatically when
requisite.
The filters to which the improvements herein first referred to exclusively relate are such
as are designed for acting in an upward direction and are provided with arrangements
for cleansing of the filtering medium by downward passage of filtered liquid through
the filter beds and the said improvements consist in forming the filter bed of smaller
sectional area at the lower part than at the upper part, or in placing the material
of which the said bed is composed within a receptacle of smaller sectional area at
the lower part than at the upper part the object being to cause the cleansing
liquid to act more forcibly in the part of the bed where the principal deposit of
matter separated from liquid 'being filtered takes place than at other parts of the
said bed. In order to prevent disturbance of the filtering material by passage of
liquid through the filter bed a layer of pebbles or fragments of matter of high specific
gravity such as manganese or heavy spar is placed on the uppermost layer or on it
is placed a perforated plate connected to a screwed rod by turning which in
one or other direction the said plate may be readily raised and lowered according to
requirements.
The arrangements for permitting of escape or separation of air and gas from liquids
passing to filters are applicable to upwardly acting filters and consist in a chamber
situated between the filter and the conduit conveying the liquid to be filtered and
communicating both with the said conduit and with the inlet of the filter which
chamber has an opening or openings in its upper part at a higher level than that of
the liquid to be filtered or has connected to its upper part a pipe or pipes opening
above the level of the liquid to be filtered. By means of this arrangement air or gas
contained in the liquid passing through the supply conduit is allowed to escape or
separate from the said liquid before it enters the filter the said air or gas rising in
the said chamber and escaping from the surface of the liquid therein and passing from
the said chamber by the opening or openings or pipe or pipes at the upper part
thereof. The said chamber may be conveniently constructed in the form of a
casing surrounding a receptacle containing the filter bed or surrounding the lower
part of such receptacle but the said chamber may be arranged apart from the filter
receptacle and in connection with the supply conduit only.
The arrangements for causing dispersion or diffusion of cleansing liquid within
filter beds consist of conduits communicating between the supply of cleansing
liquid and the said beds and adapted to conduct the said liquid into and deliver it
within the interior of the bed of filtering material the inlet mouths of which
conduits are by preference provided with valves so arranged so as to permit free entry
thereto of the cleansing liquid and to prevent passage therethrough of liquid being
The said conduits may consist of perforated annular pipes situated within
filtered.

page_text: the part of the filter bed from which filtered water passes and connected with branch
pipes communicating with a receptacle in which the filtered liquid collects the
said branch pipes having buoyant valves so arranged within them as to automatically
close the said pipes against the passage of liquid passing in the filtering direction
and leave them open for the passage of liquid passing in the cleansing direction.
The said annular pipes may be furnished with branch discharge pipes projecting in
various directions into the bed of filtering medium for producing dispersion or
diffusion of the cleansing liquid within the said bed. To prevent obstruction of
the perforations in the aforesaid pipes by particles of the filtering material a plate
or shield or sheath or plates or shields or sheaths of suitable forin may be arranged
over or around the said pipes or in such other positions relatively thereto as may be
desirable.
The improvements in apparatus or plant whereby the cleansing of filters is caused
to take place automatically when requisite are especially applicable to upwardly
acting filters and are hereinafter described with reference to such filters. The main
objects of the said improvements is to avoid the waste or extravagant use of filtered
liquid which is unavoidable in the case of such apparatus or plant as has heretofore
been proposed for the said purpose.
According to the said improvements provision is made for collection and retention
of a considerable quantity of filtered liquid above the level of the filter bed during
the filtering action and the pipe for supply of liquid to the filter and a pipe
(hereinafter termed the escape pipe) by which cleansing liquid passes from the filter
are furnished with valves or cocks so connected with a float (hereinafter termed the
valve float) arranged within a suitable vessel (hereafter termed the float box) that the
supply to the filter is cut off and the escape pipe is opened by rising of the said float
which is caused by inflow of liquid to the float box into which a portion of the supply of
unfiltered liquid passes directly or indirectly when the action of the filter is obstructed
by accumulation in the filter bed of matter separated thereby from the liquid being
filtered. To provide for automatic outflow of liquid from the float box according to
requirements it is furnished with a weighted valve so connected to a float supported
'by the filtered liquid accumulating above the level of the filter bed that descent of
the said float causes the opening of the said valve and ascent of the said float permits
of the said valve being closed by the action of its weight. By means of this
arrangement the quantity of filtered liquid which while the filter bed is in action
collects and is retained above the level thereof is permitted to descend through the
said bed by the opening of the valve in the escape pipe through the medium of the
valve float the actuation of which float is produced by inflow to the float box of a
'portion of the supply of unfiltered liquid the passage of which into the said float box is
consequent on clogging or obstruction to the action of the filter bed by accumulation
therein of matter as before stated. After the filter bed has been cleansed by descent
through it of the aforesaid quantity of filtered liquid the consequent descent of the
float supported by the said liquid causes the outlet valve of the float box to be
opened whereby escape of liquid from the said box is permitted the effect being descent
of the valve float and closing of the valve in the escape pipe and opening of the valve
in the supply pipe. The filtering action is thus re-established and continues until
a further accumulation of matter in the filter bed causes repetition of the
automatically governed action of the cleansing apparatus as herein before described.
Figure 1 of the accompanying drawing is a vertical section of an upwardly acting
filter embodying the improvements herein before described and having combined
therewith arrangements of the kind hereinbefore described for permitting escape of
air and gas from the liquid passing thereto and for conducting the cleansing water
into the filter bed and apparatus or plant of the kind herein before described for
causing automatic cleansing of the filter when the passage of liquid through the bed
is obstructed by accumulation therein of matter separated thereby from the liquid
under treatment.
a is the receptacle for containing the. bed of filtering material which is not
represented in the accompanying drawing. In the lower part of the said receptacle

page_text: is a grid b for supporting the filtering material and below it are perforations c c
constituting the inlet through which the liquid to be filtered enters the said
receptacle. The means illustrated for preventing the filtering material from rising
when liquid to be filtered is passing upward through the said bed consists of a
perforated plate d which may be raised and lowered by means of a screwed rod e
provided with a handle f and working in a screwed hole in a fixed bar g. h is
the pipe or conduit for supply of liquid to be filtered. i is the chamber situated
between and communicating with the said conduit and the inlet of the filter
receptacle in which chamber air or gas escaping from the liquid to be filtered rises.
jj are the pipes by which such air or gas passes from the said chamber . k is the
part of the filter receptacle in which filtered liquid collects when the filter is in
action and which constitutes a retaining reservoir for a quantity of the said liquid
sufficient to effect cleansing of the filter bed when necessary. is a pipe by which
the filtered liquid passes from the reservoir k and m is the escape pipe for conducting
cleansing liquid away from the apparatus after such liquid has passed downward
through the filter bed.
The arrangement for effecting dispersion or diffusion of the filtered liquid within
the filter bed for the purpose of cleansing it consists of an annular perforated pipe n
mounted in the upper part of the receptacle a and provided with branch pipes o o
opening into the reservoir k the mouths of which pipes o o are provided with buoyant
valves acting automatically to prevent upward passage and adinit of downward passage
of liquid through the said pipes. A suitable arrangement of valve for the said
purpose is illustrated in Figure 2 of the accompanying drawing which represents a
section of one of the said branch pipes oo the buoyant ball valve which is marked o¹
being confined within a cage o2 so that upward passage of liquid in the reservoir k
causes the mouth of the pipe o to be closed by the said valve the passage of
downwardly flowing liquid being unimpeded thereby.
The valves or cocks in the supply pipe h and discharge pipe m which control the
passage of liquid through the said pipes are marked respectively h¹ m. p is the
float to which the said valves are connected and by which they are actuated
automatically. q is the float box which receives unfiltered liquid from the pipe m
the said liquid passing from the said pipe into a branch pipe and thence into a
receptacles from which when it is nearly full the said liquid passes through a
syphon t into the said float box q. q¹ is the discharge cock of the said float box q
which cock is normally kept closed by a weighted lever 72. u is the float in the
filtered liquid reservoir the descent of which float causes the lever q' to be actuated
so as to open the cock q' through the medium of a cord v passing over pulleys and
working in a hole in the said lever q² and furnished at its free end with a knob v¹
which prevents it from being drawn entirely through the said 'hole. The said cord is
thus so connected to the said lever that the latter is raised and the cock q' opened by
descent of the float in the reservoir . when it has descended to a predetermined
distance below the level of the outflow pipe l.
The action of the entire apparatus is as follows. When the supply pipe h is open
and the filtering action is in progress, the liquid to be filtered passes into the
chamber where air and gas escape from the said liquid and whence it passes into
the lower part of the filter chamber a through the inlets.cc and thence passes upward
through the filter bed and accumulates in the reservoir k until the level of liqnid
therein rises to the height of the overflow pipe through which the filtered liquid
passes from the apparatus. When the liquid being filtered is prevented from passing
freely through the filter bed in consequence of accumulation of foul matter in the
said bed a portion of the said liquid passes through the pipe m and branch into the
box s and accumulates therein until it has risen above the bend of the syphon it when
the liquid passes from the said box through the said syphon into the float box q the
rising of the float p in which box causes closing of the valve h¹ and opening of
the valve m¹. The supply of liquid to the filter being thus cut off and the discharge
pipe m opened the filtered liquid above the filter bed deseends through the said.be

page_text: washing therefrom the matter deposited therein during upward filtering and escapes
by the said pipe m. The perforated annular pipe n and its branch pipes o o assist
in the cleansing operation by causing distribution of the descending filtered liquid
through the bed of filtering media in the receptacle a. Where desirable the said
distribution may be further provided for by means of horizontal branch pipes
projecting from the inner portion of the annular pipe n as herein before stated. In
consequence of the sectional area of the receptacle a being considerably smaller at
the lower part than at the upper part the velocity of flow of the cleansing liquid
increases as it passes through the lower part of the bed where the principal
accumulation takes place of matter separated by the filtering material from liquid
while being filtered which matter is thus effectually removed from the filter bed.
On descent of the washing liquid as described the consequent descent of the float u
causes the outlet valve q¹ of the float box q to be opened whereby escape of the liquid
in the said box is permitted the consequence being descent of the float p in the said
box and opening of the valve. ¹ in the supply pipe h and closure of the valve m¹
in the discharge pipe m. After these actions have taken place the supply of liquid
to the chamber i and upward passage of the said liquid through the filter and
outflow of the filtered liquid through the pipe again proceed until the passage
of the said liquid through the filter bed becomes again sufficiently obstructed to
cause automatic action of the cleansing arrangements as herein before described
to take place again.
The invention is not restricted to the precise arrangement of apparatus or plant
herein before described with reference to and illustrated in the said Figure 1 as
various modifications may be made therein without departing from the nature of the
said invention. For instance a ball cock or other like device may be used for
operating the valves h¹ and m¹ instead of the arrangement of syphon t and box s
illustrated and the liquid to be filted may be delivered from the supply pipe h into
a box as illustrated in Figure 3 the said box (which is marked x in the said Figure 3)
being connected to the filter by means of a pipe y and provided with a syphon z
arranged to discharge into the float box q illustrated in Figure 1. By this means
the pipe illustrated in the said Figure 1 is dispensed with. When the arrangement
illustrated in the said Figure 3 is used the action is substantially the same as
already described with reference to the said Figure 1. That is to say when the
passage of liquid through the filter bed becomes sufficiently obstructed by accumulation
of foul matter therein the liquid passing to the filter gradually rises in the box a
until it overflows through the syphon z into the float box q.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed We declare that what We
claim :-
:-
First The improvement hereinbefore described in upwardly acting filters
provided with arrangements for cleansing of the filtering material by downward
passage of filtered liquid through the filter beds which improvement consists in
placing the filter bed within a receptacle of smaller sectional area at the lower part
than at the upper part for the purpose of causing the cleansing liquid to act more
forcibly in the part of the bed where matter separated from liquid being filtered
accumulates than at other parts.
Secondly:-The arrangement herein before described whereby escape of air or gas
from liquids prior to subjecting them to the action of an upwardly acting filter is
provided for which arrangement consists in a chamber having an outlet or outlets at
its upper part and situated between the pipe conveying the liquid to be filtered and
the filter into which the said liquid is to pass in which chamber the said air and gas
rise and from which they pass by means of the said outlet or outlets.
Thirdly; The improvements herein before described in arrangements for washing
or cleansing filters by means of reverse flows through the filter beds of filtered liquid
which improvements consist in pipes communicating with the supply of cleansing

page_text: liquid and arranged to conduct the said liquid into and deliver it within the interior
of the bed of filtering material substantially as hereinbefore described.
Fourthly The combination with upwardly acting filters of apparatus arranged
and acting substantially as hereinbefore described and illustrated in the accompanying
drawing for causing automatic cleansing of such filters by descent through them of
liquid which has been filtered by passing upwardly through them the action of which
apparatus is automatically determined by obstruction to upward passage through the
filter bed of liquid to be filtered being caused by collection in the said bed of matter
separated thereby from the liquid under operation.
Dated this fifteenth day of November 1907
W. T. WHITEMAN
Agent for the Applicants.