Improvements in and in Apparatus for Use in or in connection with the Purification of Sewage and Impure Waters.
Year: 1895

page_text: Date of Application, 2nd Jan., 1895
Complete Specification Left, 4th Nov., 1895-Accepted, 28th Dec., 1895
PROVISIONAL SPECIFICATION.
Improvements in and in Apparatus for Use in or in connection with
the Purification of Sewage and Impure Waters.
1, FRANK PULLEN CANDY of 29 Higher Albert Street Eccles in the County
of Lancaster Sanitary Engineer do hereby declare the nature of this invention to
be as follows
My invention consists firstly in improvements connected with the precipitation of
sewage and impure waters and has for its object the more thorough aggregation
cr separation out of the suspended matter or coagulum in or obtained in sewage or
impure waters, secondly in improved means whereby filter beds or sewage or
impure waters can be acrated or supplied with air or other gas, thirdly in improved
means or manner for or of constructing filter beds so that the same can be readily
and economically cleaned, fourthly in improvements in precipitation tanks and
fifthly in apparatus for the addition of sludge or other liquid to sewage.
The sewage and impure waters I will hereafter speak of as
sewage."
In carrying the first part of my invention into effect I pass the sewage con-
taining the suspended matter, preferably after the addition of a suitable precipitant,
through a bed or layer or layers composed of material such as gravel or large
pebbles or other suitable substance or substances and contained in a suitable tank
or receptacle. The flow of sewage through the said material may be downwards
or upwards and the sewage is passed therethrough at such a speed and the material
is of such size or sizes that the suspended matter in the sewage shall fall upon or
come in contact with the surfaces of the said material and shall then be carried or
fall into a depositing tank or chamber. By this arrangement the particles of
suspended matter are brought into intimate contact or touch with each other
whereby they are rendered larger and heavier and are thus more easily and quickly
removed by deposition. I would have it clearly understood I do not intend to
use the aforesaid bed or layer or layers of material as an ordinary filter bed but
that I use the said bed or layer or layers of material as an aggregating agency
for the particles of suspended matter. I prefer to use material having a smooth
surface and sometimes use glass or glazed stoneware balls or granules or, the like,
and may use material of different sizes. I sometimes arrange that the aforesaid
bed or layer or layers of material may be used alternately for upward or down-
ward passage of the sewage. It is important that the sewage after having
passed the aforesaid layer or layers of material shall not receive any considerable
agitation or disturbance before entering the depositing chamber, otherwise the
aggregated particles may be broken up.
Another head of the first part of my invention consists in passing the sewage,
after the required precipitant has been added thereto, upwardly through a
chamber or chambers, (which I will call the "aggregating chamber", before the
said sewage enters the precipitation tank, by which said upward passage the
particles of coagulum are aggregated together; after the passage of the sewage
through the said aggregating chamber it is essential, in order that the full benelit
shall be derived, that the said sewage in its passage to or into the precipitation
tark shall not undergo any eddying, splashing or other rapid or agitating motion
which would break up the large particles of coagulum obtained in the upward flow
through the aggregating chamber. The flow of sewage through the aggregating

page_text: chamber requires to be neither too rapid nor too slow. When the' sewage is
required to enter a precipitation tank at about the bottom thereof it is necessary
(unless the aggregating chamber be sunk) that the sewage shall be brought from
the top of the aggregating chamber down again to the required depth, there will
thus be required a conduit or conduits to conduct the sewage to the bottom of
the aggregating chamber and another conduit or conduits to conduct the sewage
from the top of the aggregating chamber to the bottom part of the precipitation
tank.
The sewage may be passed upwardly through more than one of the said aggre-
gating chambers which would be suitably connected together previous to entering
the precipitation tank, or "tank,effluent" may be passed through one or more
aggregating chambers previous to being passed through a filter bed or being again
passed into or through a precipitation tank.
The aggregating chamber as before described is not a mixing tank nor is it a
depositing tank but I sometimes provide it with means for the withdrawal of auy
sediment that may deposit therein.
As a modification of the before described arrangement of aggregating chamber
I sometimes use two or more aggregating chambers connected together and pass
the sewage therethrough at a slower speed so that deposition shall take place
therein and I provide efficient means to catch and remove the sediment or sludge ;
the said connected aggregating chambers are of different sizes so that the speed of
How therethrough shall be that best suited for the aggregating of the differing
stages of precipitation in the said various aggregating chambers.
In connection with the before mentioned aggregating chamber or chambers'
[ construct the divisional wall or walls over which the sewage flows in its change
from an upward to a downward. flow at a sufficient level below the top level of the
water that no breaking up of the aggregated coagulum shall take place.
The said aggregating chamber or chambers I form as deep as convenient for
instance it or they may be from about four feet to twenty feet deep, if a com-
paratively small depth only is available it is generally necessary to pass the sewage
through more than one of the said aggregating chambers while it a considerable
depth be available the passage of the sewage through one deep said aggregating
chamber is sometimes sufficient.
When the construction of the aggregating chamber is such that an inlet conduit.
is required to convey the sewage to the bottom of the said aggregating chamber,
and an outlet conduit is required to convey the sewage from the top of the said
aggregating chamber to the precipitation tank or to another aggregating chamber
I preferably provide a connection, provided with a suitable valve if necessary,
between the said aggregating chamber and the said outlet conduit so that I avoid
the necessity of building the dividing wall strong enough to bear the full pressure
of the water.
When I construct the aggregating chamber of a circular form with inlet and
outlet conduits as aforesaid I preferably also construct the said inlet and outlet
conduits of a circular form and place them one within the other. I sometimes
form the aggregating chamber cone or pyramid shaped or of varying area or areas.
These arrangements are also applicable to the before described modification of the
aggregating chamber.
I preferably construct the aggregating chamber or chambers vertically but
sometimes construct it or them in a slanting position.
I am aware that sewage has flowed in an upward direction previous to entering
a precipitation tank but it has never been caused to flow for the requisite distance
and at the requisite speed and to enter the precipitation tank in a sufficiently gentle
manner to obtain the improved results which I obtain by the before described
aggregating chamber or chambers.
Or I sometimes aerate sewage or a filter bed in the following manner I construct
a chamber or receptacle (which I will call the down chamber) preferably of
tubular form and preferably deep and preferably built or laid vertically, and

page_text: connectut from the bottom part to the bottom part of another chamber or receptacle
(which I will call the up chamber) of about the same height, so that the sewage
may flow down the one and up the other, or I connect the said down chamber at the
bottom part to a filter bed the connection to the filter bed being preferably at the
bottom of the said filter bed, or I sometimes connect the said up chamber to a
filter bed preferably at the bottom part of the said filter bed.
When I provide a down and up chamber as aforesaid I may form them of one
tube or chamber divided across its diameter or divided radially or otherwise divided.
I cause the sewage to enter the said down chamber at the top thereof and from a
height and in such manner that as large a quantity as possible of air may thereby
be carried into the sewage, the said sewage then flows down the said down chamber
or receptacle at such a speed that it carries along with it a considerable portion
of the air previously caused to be dashed into it, whereby the said air is brought
into and retained in intimate contact with the sewage. The contact of the air
with the sewage is obtained both in the down and up chambers, or when the sewage
containing the air is delivered into a filter bed as before described the filter bed is
aerated whereby increased purification is effected.
These aeratings of the sewage may be repeated as often as necessary.
"
The bottom part of the aforesaid down chainber may be smaller than the other
part and the top part of the said down chamber may be provided with an enlarged
mouth or funnel, the said chamber is preferably deep so that the air in the sewage
when it reaches the bottom shall be under some artificial pressure.
Instead of causing air to be dashed into the sewage as aforesaid I may blow or
force air or other gas into the sewage in the said chamber or I may dash air or
other gas into the said sewage by means of a nechanical arrangement similar to a
water wheel, or by other mechanical means.
The before described methods of aeration are applicable to "crude "
to settled or to precipitated or to filtered sewage.
sewage or
Instead of ordinary atmospheric air I may aerate with oxygen or with ozone or
with the products of the combustion of coal or coke or sulphide of iron or of other
suitable material or mixtures thereof. Aeration with combustion products as
aioresaid is advantageous when it is desired to neutralize any alkalinity of sewage.
In aerating with other gas than atmospheric air by means of down and up
chambers as aforesaid I sometimes connect the conduit (which brings the sewage
to the said down chamber) to the said down chamber or to an extension or enlarge-
ment thereof in an air tight manner an opening or openings being provided which
are connected with a supply of the required gas whereby the gas which is carried
away by the sewage comes from the required source.
When the gas
use is combustion products I sometinies provide a fire and make
the only exit of gas therefrom to be through the sewage flowing along the down
tube.
I prefer to form the aforesaid up chamber of considerably greater capacity than
that of the down chamber and sometimes employ more than one down chamber
delivering into a filter bed or into a large up chamber.
As a modification I sometimes work the aforesaid aerating tubes as a syphon and
provide each end with valve and a water seal, the sewage flowing first upwards
and then downwards. The up tube in this case is preferably the larger and I
sometimes provide it with a restricted inlet neck. The air is dashed or blown into
the water seal of the up tube or into the up tube itself.
A further head of the second part of my invention consists in forcing air into a
filter bed or irawing air out of a filter bed by the following method:
I provide one or more air tight receptacles which will call the air tube,
furnished with inlet or inlets and outlet or outlets both for the sewage and for the
air, into which the sewage first flows and then flows out; the number of the said
air tubes I prefer to use is three; each said air tube is provided with an inlet and
outlet for the sewage and an inlet and outlet for the air, suitable valves or arrange-
ment being provided so that the sewage shall flow into one said air tube which

page_text: when full shall commence to run off, the sewage meanwhile passing into another
air tube which in its turn shall fill and empty and so on for each said air tube
provided the inlet and outlet for the air to and from the said air tube is
connected with the filter bed suitable valves or arrangement being, interposed so
that the air or gas forced out of the said air tube when the sewage is filling
the same is either passed into the filter hed and the air or gas required to fill
the said air tube when the sewage is, passing therefrom is drawn from the
atmosphere or from some other supply of suitable gas, or the air or gas required
to fill the said air tube when the sewage is passing therefrom is drawn through
the filter bed and discharged into the atmosphere when the said air tube is
filling with sewage, in this latter case the gas drawn through the filter bed may
be taken from a supply of any suitable gas, instead of atmospheric air
employ oxygen or ozone or carbonic oxide or sulphurous acid or other gas.
I preferably arrange the various valves or the like to work automatically.
In the third part of my invention I may filter either upwardly or downwardly.
In filtering upwardly provide means for drawing away the dirty or fouled
filtering material or a part or portion thereof as required from the bottom part
of the filter bed and for allowing the reminder of the material to sink down
in the filter and take the place of that which has been removed, clean material
being added to the top part of the filter when necessary.
may
As an illustration of method of carrying this into effect 1 form a chamber or
tank which I will call the filter tank) to contain the filtering material, the bottom
part of the said filter tank being provided with a means whereby a part of its
contents can be discharged either direct from the filter tank or else into a second
chamber or receptacle (which I will call the receiving chamber) from which the
said discharged contents can be conveniently removed, for instance by a belt
and cups.
"
The aforesaid means for discharging part of the contents of the filter chamber
into the receiving chamber may be a movable shutter or shutters or slide or
slides, or a fixed grid or grids and a movable grid or grids, or one or more
movable or collapsible cones or part or parts thereof; or an exit pipe or pipes,
provided with a valve or valves and preferably in combination with any of the
before mentioned removal arrangeinents or other like or suitable arrangement or
arrangements such as a worm conveyor or conveyors, may be employed to discharge
the filtering material direct from the filter tank. Movable arms or stirrers are
provided if required.
I sometimes interpose a suitable watertight valve, between the filter tank and
the receiving chamber or between one part and another part of the said receiving
chamber.
When I employ a pipe or pipes as beforementioned to remove the filtering
material the exit of the pipe is preferably carried up as high as possible, the
filtering material being forced out by the pressure of the water on top of the filter
bed, or sucked out by any suitable means, or extracted by a combination of both;
one end of the said pipe or pipes is arranged in the filter tank so that the filtering
material can be extracted therethrough as desired and the other end of the said
pipe or pipes is carried to a suitable position and discharges the filtering material,
sewage being discharged at the same time, the discharge may be into a suitable
receptacle which acts as a washing box, and after undergoing a cleansing operation
the filtering material may be discharged or conveyed into the filter tauk again.
Sewage either before or after the filtration may be used in the said cleansing
operation. When I wish to obtain pressure to force out the filtering material to a
considerable height 1 construct a deep filter tank and place the filtering material
only in the lower part thereof thereby obtaining sufficient head for the purpose.
One of the main features of this improved filter is that the sewage can be
delivered after filtration to almost the same level as that at which the unfiltered
sewage is delivered to the filter."
The pipe or pipes for withdrawing the fouled filtering material are arranged as
**

page_text: most suitable. The inlet mouth of the pipe may face towards the top or the
bottom or the side of the filter bed. I may provide branch pipes attached to a
main, or a number of separate pipes, or one or more pipes with openings therein, or
may employ a movable pipe or pipes; or any suitable combination of these.
I also sometimes employ agitating arms, or perforated plates or grids or the like,
or worm conveyors or combinations thereof. I sometimes also remove the whole of
the filtering material at a time through the aforesaid pipe or pipes. I sometimes
provide one or more controllable jets or streams of sewage or water which flow
into the mouth or mouths of the aforesaid pipe or pipes and thereby carry away or
aid in carrying away the filtering material through the said pipe or pipes. The
said mouth or mouths may be either enlarged or contracted or both. I sometimes
provide two exits from each of the said pipe or pipes both provided with valves
one exit being lower than the other, the lower exit can be opened first to start the
extracting of the filtering material which being achieved the higher exit can be
opened and the lower one closed.
When I require the filtering material to slide down an inclined surface I
sometimes provide a travelling or jigging arrangement to effect the same.
When I filter downwards I withdraw the fouled material from the top of the
filter bed and add clean material when required to the exit end of the filter bed;
I employ any suitable mechanical arrangement to remove the fouled material and
bring the clean material into its place, for instance an endless chain with discs or
the like may be employed.
As a modification I sometimes filter both upwards and downwards for instance
the two filter tanks may then be of a V or U shape and I add clean filtering
material at the top part of one of the filter tanks and remove the fouled material
from the top part in the other filter tank.
.
I sometimes supplement the before described means of cleaning a filter bed by a
quick flush of sewage (or water) through the filtering material; or 1 sometimes use
a quick flush of sewage (or water) alone to effect the cleaning, as hereafter
described.
out
In carrying out this part of my invention 1 provide a valve or valves for the
exit of the sewage, so placed and of such a size that when the same is or are opened
a sufficiently quick flush of sewage shall take place through the filtering material
to remove the accumulated dirt. I preferably filter upwards and wash
downwards and preferably provide a head of filtered sewage on top of the filtering
material or at a higher level than the same, which said head of filtered sewage
shall come into operation or use during the washing out of the filtering material.
I preferably provide also a chamber or receptacle, which 1 will call the flushing
sewage chamber, into which the sewage shall flow after having been used for the
said flushing; the said flushing sewage chamber serves as a precipitation tank and
is provided with means for withdrawing or passing away the precipitated flushing
sewage and with means for removing the sludge. I prefer to work the said
flushing sewage chamber as a continuous flow precipitation tank so arranged that
the intermittent flushes of sewage shall push out before them the sewage from the
previous flush which said sewage shall then be clear and comparatively pure.
1 sometimes add a suitable chemical agent to the said flushing sewage to aid its
treatment in the said flushing sewage chamber.
I prefer to place the exit of the said flushing sewage from the said flushing water
chamber at as high a level as possible consistent with obtaining a sufficiently rapid
flush of sewage.
i >>
The beforementioned glass or glazed stoneware balls or granules are especially
suitable for use in a filter bed which it is desired to clean by flushing..
: J
The filtering material I use in the third part of my invention is preferably in
coarse granules or particles for instance from about the size of coarse sand or grit
to that of gravel.
The sewage may enter the filtering material through perforations or slots in or
provided in the beforementioned slides or shutters or grids or cones, or it may

page_text: enter through a pipe or pipes placed in the bottom part of the filter bed and
preferably slotted or perforated the said slots or perforations being preferably on
the under side of the said pipe or pipes; or the sewage may enter in other ways.
may use any suitable combination or combinations of any of the before-
mentioned inventions.
The fourth head of my invention relates to improvements in precipitation
tanks―
The first part of this fourth head relates most especially to deep circular tanks
and consists in providing such a tank with a bottom or floor constructed in the
shape of a cone the apex of the said cone pointing towards the top of the tank, the
base of the said cone may either touch or be at some distance from the side of
the said precipitation tank and in the latter case the side of the said tank may be
sloped towards the said cone; around the base of the said cone is placed a
perforated or slotted pipe or pipes connected to a suitable point or points outside
the said tank and provided with a valve or valves, the sludge being withdrawn
through the said pipe or pipes, or the sludge may be withdrawn in other ways.
1 sometimes admit the sewage into the said tank through an opening or openings at
the top or at the sides or at both the top and the sides of the said cone and when
the sewage inlet conduit passes through the said cone sometimes provide a
connection or connections from the said inlet conduit, at a point about half way up
the cone or at other suitable point or points, to the body of the said tank so that
any sludge accumulated in the said inlet conduit may pass out through the said
connection or connections; the said sewage inlet conduit is preferably shaped like
an inverted cone, this said arrangement of connection or connections from the
sewage inlet conduit to the body of the tank is applicable to any similar inlet
conduit. I sometimes use more than one conc as aforesaid on the bottom of the
precipitation tank.
Another part of the fourth head of my invention relates to improvements in the
admission of the sewage to upward flow tanks and consists in forming concs
approximately shaped in cross section over the bottom of the tank, these
approximately A shaped ridges are placed close together and have an opening or
openings at or about their apex, the said ridges being as it were hollow, the sewage
enters the hollow of the said ridges and disperses into the tank through the
aforesaid opening or openings, perforated or slotted pipes are placed between the
said ridges through which the sludge is withdrawn.
The fifth part of my invention relates to a new or improved apparatus for adding
sludge or other substance or substances to sewage whereby the choking up of the
outlet by comparatively large pieces of suspended matter is avoided and the flow
of sludge equalised. The apparatus consists of a tank or receptacle provided at
the bottom part with an outlet conduit which is pivoted or otherwise arranged so
that the exit end of the outlet conduit can be raised to about the top of the said
tank or receptacle, a float is provided inside the tank and is connected by a
shaped rod or tube or otherwise suitably connected to the said outlet conduit, a
means for regulating the exact position of the exit end of the outlet conduit in
comparison with the position of the said float is also preferably provided. To set
the apparatus working the aforesaid tank or receptacle is charged with sludge, or
other liquid, and the exit end of the said ontlet pipe is attached to the connection
to the said float so that the exit end aforesaid is slightly lower than the level of
the sludge in the said tank or receptacle, thus the required amount of sludge is
delivered from the outlet conduit, which by means of the float retains its relative
position to the level of the sludge in the said tank or receptacle; it is important
that the said outlet conduit be amply large.
Dated this First day of January 1895

page_text: Improvements in and in Apparatus for Use in or in connection with
the Purification of Sewage and Impure Waters.
FRANK PULLEN CANDY of No. 29 Higher Albert Street Eccles in the
County of Lancaster Sanitary Engineer 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:-
My invention consists firstly in improvements connected with the precipitation of
sewage and impure waters and has for its object the more thorough aggregation or
separation out of the suspended matter or coagulum in or obtained in sewage or
impure waters; secondly in improved means whereby filter beds for sewage.
or impure waters can be aerated or supplied with air or other gas thirdly in
improved means or manner for or of constructing filter beds so that the same can be
readily and economically cleaned, fourthly in improvements in precipitation tanks
and fifthly in apparatus for the addition of sludge or other liquid matter to sewage.
The sewage or impure waters I will hereinafter speak of as "sewage."
In carrying the first part of my invention into effect I pass the sewage containing
the suspended matter after the addition of a suitable precipitant through a bed or
layer or layers composed of material such as gravel or large pebbles or other
suitable substance or substances and contained in a suitable tank or receptacle.
The flow of sewage through the said material may be. downwards or upwards and
the sewage is passed therethrough at such a speed and the material is of such size
or sizes that the suspended matter in the sewage shall fall upon, or come in contact
with the surfaces of the said material and shall then be carried or fall into a
depositing tank or chamber. By this arrangement the particles of suspended
matter are brought into intimate contact of touch with each other whereby they
are rendered larger and heavier and are thus more easily and quickly removed by
deposition. 1 would have it clearly understood I do not intend to use the aforesaid
bed or layer or layers of material as an ordinary.filter, bed but that I use the said
bed or layer or layers of material as an aggregating agency for the particles of
suspended matter." I prefer to use material having a smooth surface and sometimes
use glass or glazed stoneware balls or granules or the like of a size from about that
of marbles to about that of walnuts. I may however use material of different sizes.
I sometimes arrange that the aforesaid bed or layer or layers of material may be
used alternately for upward and downward passage of the sewage. It is important
that the sewage after having passed the aforesaid layer or layers of material shall
not receive any considerable agitation or disturbance before entering the depositing
chamber otherwise the aggregated particles may be broken up.
с
Figures 1 and 2 of the accompanying drawings illustrate apparatus suitable for
use in carrying out this part of my invention Figure 1 being a plan and Figure 2. a
vertical section of the said arrangements. Referring to the said figures a is.a
chamber provided with an inlet b and having a perforated floor c which may be
formed of pierced tiles supported on bricks or otherwise formed and supported
beneath which floor is a space d communicating with another chamber e having an
outlet at its upper part. In the said chamber a are placed the balls pebbles or
other aggregating agents which are not shown in the drawings. In using the said
apparatus the sewage to be treated is admitted at the inlet and descends among
the aggregating agents in the chamber a and passes through the perforations (not
shown) in the Hoor c and flows from the space d into the chamber e in which it rises
and from which it passes by the outlet which may communicate with a precipita-
tion tank. The line o indicates the water level and the line indicates a suitable
height for the bed of aggregating material.
g
Instead of providing for outflow of the treated sewage at about the same level as.

page_text: the inflow in some cases provide for the outflow at a lower level. In such
cases provide for distribution of the inflowing stream of sewage over the surface
of the bed of aggregating material by arranging on or above the said surface troughs
to which the sewage is conveyed and from which it overflows or by any other
convenient means.
In some cases I arrange for flow of sewage through the apparatus in a direction
the reverse of that hereinbefore described and in some cases I connect. the space d
with a precipitation tank and dispense with the chamber e.
The sewage may be allowed to flow through the chamber at the rate of from
about three feet to about six feet per minute.
Another head of the first part of my invention consists in passing the sewage
after the required precipitant has been added thereto upwardly through a chamber
or chambers (which I will call the "aggregating chainber") before the said sewage
enters the precipitation tank by which said upward passage the particles of coagulum
are aggregated together; after the passage of the sewage through the said aggre-
gating chamber it is essential in order that the full benefit shall be derived, that the
said sewage in its passage to or into the precipitation tank shall not undergo any
eddying splashing or other rapid or agitating motion which would break up the large
particles of coagulum obtained in the upward flow through the aggregating
chamber.
I have observed that aggregation of the particles of coagulum does not take
place during downward flow of sewage through the chamber and that during
upward flow the best result is produced when the rate of flow is such that the
particles are caused to come in contact as much as possible. The flow of sewage
through the aggregating chamber requires to be neither too rapid nor too slow.
I have found that a rate of flow of from about one foot to three feet per minute is
suitable and that within reasonable limits the greater the capacity of the aggregating
chamber relatively to the flow of sewage the clearer and purer will be the effluent
resulting from subsequent precipitation. For instance a chamber capable of
holding an hour's supply of sewage is preferable to one capable of holding only
half an hour's supply.
11.
When the sewage is required to enter a precipitation tank at about the bottom
thereof it is necessary (unless the aggregating chamber be sunk) that the sewage
shall be brought from the top of the aggregating chamber down again to the
required depth there will thus be required a conduit or conduits to conduct the
sewage to the bottom of the aggregating chamber and another conduit or conduits
to conduct the sewage from the top of the aggregating chamber to the bottom part
of the precipitation tank.
The sewage may be passed upwardly through more than one of the said
aggregating chambers which would be suitably connected together previous to
entering the precipitation tank or "tank effluent " may be passed through one or
more aggregating chambers previous to being passed through a filter bed or being
again passed into or through a precipitation tank. The aggregating chamber as
belore described is not a mixing tank nor is it a depositing tank but I sometimes
provide it with means for the withdrawal of any sediment that may deposit
therein.
A convenient form of aggregating chamber is illustrated in conuection with an
upward How precipitation tank in plan in Figure 3 and in vertical section
in Figure 4. i is the said chamber to which the sewage is conducted by a carrierj.
The said chamber is divided by transverse partitions into compartments m, n, n
which compartments are partially divided by walls o, o resting on girders p, p
supported above the bottoms of the compartments. In the lower part of the
compartiment m a perforated pipe g is placed through which sediment deposited by
the sewage may be withdrawn. The sewage passes through the several compart-
ments of the said chamber as indicated by the arrows and is conducted from the
said chamber to the precipitation tank by pipes rs the latter of which opens in the
lower part of the said tank. The line indicates the water level below which level

page_text: the pipe is placed in order to insure quiet or gente now of the sewage from the
chamber to the tank.
The relative sizes of the several compartments of the aggregating chamber may
he varied for instance they may be larger towards the outflow end of the chamber
and the walls o o may be so situated that the down flow passages may be smaller
than the upflow passages.
the
As a modification of the before described arrangement of aggregating chamber
I sometimes use two or more aggregating chambers connected together and pass
sewage therethrough at a slower speed so that deposition shall take place therein
and provide efficient means to catch and remove the sediment or sludge. The
said connected aggregating chambers are of different sizes so that the speed of How
therethrough shall be that best suited for the aggregating of the different stages of
precipitation in the said various aggregating chambers.
In connection with the before mentioned aggregating chamber or chambers
I construct the divisional wall or walls over which the sewage flows in its change
from an upward to a downward flow at a sufficient level below the top level of the
water that no breaking up of the aggregated coagulum shall take place.
The said aggregating chamber or chambers I form as deep as convenient for
instance it or they may be from about four feet to twenty feet deep, if a compara-
tively small depth only is available it is generally necessary to pass the sewage
through more than one of the said aggregating chambers while if a considerable
depth be available the passage of the sewage through one deep said aggregating
chamber is sometimes sufficient.
When I construct the aggregating chamber of a circular form with inlet and
outlet conduits as aforesaid 1 preferably also construct the said inlet and outlet
conduits of a circular form and place them one within the other. I sometimes form
the aggregating chamber cone or pyramid shaped or of varying area or areas.
These arrangements are also applicable to the before described modification of the
aggregating chamber.
Figures 5, 6 and 7 illustrate in vertical section arrangements and modifications of
the aggregating chamber herein before described. In all the said figures the
direction of flow of sewage is indicated by the arrows and the water level is
indicated by a broken line marked t. Parts of the said figures which correspond
to parts of Figures 3 and 4 already described are not further described but are
marked with similar letters of reference. In all the said figures the perforated
pipes cr other provision for withdrawal of deposit from the bottoms of the
compartments are marked q.
When the sewage passes through two or more compartments one after the other
the tendency is for the bulk of the sludge to deposit in the first compartment and
the suspended matter that escapes the first compartment is likely to escape the
second and the rest of the compartments if the rate of flow is the same through all.
Therefore to obtain the best results in aggregation of the suspended matters and
consequently the best effluent water it is necessary to make the second compartment
If all the com-
larger than the first, the third larger than the second and so on.
partments be of sufficiently large size practically the same results will be obtained
but at the expense of increased cost and wasted space.
Instead of providing for the passage of liquid away from one side only of the
depositing compartment of the aggregating chamber 1 in some cases arrange
troughs across the top of the said compartment for the reception of the said liquid
and its conveyance from the said compartment as required.
Any of the several parts of the arrangements illustrated in Figures 3, 4, 5, 6
and 7 may be combined in one apparatus for instance in the said figures different
shapes are shown to the bottoms of the compartments and also modifications in the
form and application of the sludge removal conduit. I may apply any of the
arrangements to each of the whole series of chambers; or I may form in Figures 5
and 6 the compartments down which the sewage flows of less capacity than those
through which the sewage flows upwardly.

page_text: I preferably construct the partition walls of the aggregating chamber o
chambers vertically as illustrated in the drawings herein before referred to bu
sometimes construct them in a slanting position as illustrated ato in Figure 8.
When the construction of the aggregating chamber is such that an inlet condui
is required to convey the sewage to the bottom of the said aggregating chamber
and an outlet conduit is required to convey the sewage from the top of the said
aggregating chamber to the precipitation tank or to another aggregating chamber
I preferably provide a connection furnished with a suitable valve if necessary
between the said aggregating chamber and the said outlet conduit so that I avoid
the necessity of building the dividing wall strong enough to bear the full pressure
of the water.
Figure 9 illustrates in section a portion of an aggregating chamber provided
with suitable connections and valves for this purpose. being the connections
and the valves w are chains by which the said valves are worked.
AD
alternative arrangement for the same purpose consists of passages furnished with
valves and formed in the lower part of the side walls of the chamber and
communicating between its interior and a conduit on the outer side thereof.
I am aware that sewage has flowed in an upward direction previous to entering
a precipitation tank but it has never been caused to flow for the requisite distance
and at the requisite speed and to enter the precipitation tank in a sufficiently
gentle manner to obtain the improved results which I obtain by the before
described aggregating chamber or chambers.
In carrying the second part of my invention into effect I aërate sewage or a
filter bed in the following manner. I construct a chamber or receptacle (which
1 will call the down chamber) preferably of tubular form and preferably deep and
preferably built or laid vertically and connected from the bottom part to the
bottom part of another chamber or receptacle (which I will call the up chamber) of
about the same height so that the sewage may flow down the one and up the ether
or I connect the said down chamber at the bottom part to a filter bed the
connection to a filter bed being preferably at the bottom of the said filter bed or
I sometimes connect the said up chamber to a filter bed preferably at the bottom
part of the said filter bed.
'
When I provide a down and up chamber as aforesaid I may form them of one
tube or chamber divided across its diameter or divided radially or otherwise
divided cause the sewage to enter the said down chamber at the top thereof and
from a height and in such manner that as large a quantity as possible of air may
thereby be carried into the sewage the said sewage then flows down the said down
chamber or receptacle at such a speed that it carries along with it a considerable
portion of the air previously caused to be dashed into it whereby the said air is
brought into and retained in intimate contact with the sewage. 1 have found a
speed of about 20 feet per minute suitable. The contact of the air with the sewage
is obtained both in the down and up chambers or when the sewage containing the
air is delivered into a filter bed as before described the filter bed is aërated whereby
increased purification is effected.
These aeratings of the sewage may be repeated as often as necessary.
The
bottom part of the aforesaid down chamber may be smaller than the other part
and the top part of the said down chamber may be provided with an enlarged
mouth or funnel the said chamber is preferably deep so that the air in the sewage
when it reaches the bottom shall be under some artificial pressure.
Instead of causing air to be dashed into the sewage as aforesaid I may blow or
force air or other gas into the sewage in the said chamber or I may dash air or
other gas into the said sewage by means of a mechanical arrangement similar to a
water wheel or by other mechanical means.
The before described methods of aëration are applicable to "crude
to settled or to precipitated or to filtered sewage.
"
sewage or
Instead of ordinary atmospheric air I may aërate with oxygen or with ozone or
with the products of the combustion of coal or coke or sulphide of iron or of other

page_text: suitable material or mixtures thereof. Aeration with combustion products as
aforesaid is advantageous when it is desired to neutralize any alkalinity of
sewage. In aürating with other gas than atmospheric air by means of down and
up chambers as aforesaid I sometimes connect the conduit (which brings the
sewage to the said down chamber) to the said down chamber or to an extension or
enlargement thereof in an airtight manner an opening or openings being provided
which are connected with a supply of the required gas whereby the gas which is
carried away by the sewage comes from the required source.
When the gas 1 use is combustion products I sometimes provide a fire and
make the only exit of gas therefrom to be through the sewage flowing along the
down tube.
I prefer to form the aforesaid up chamber of considerably greater capacity than
that of the down chamber and sometimes employ more than one down chamber
delivering into a filter bed or into a large up chamber.
Figure 11 of the accompanying drawings represents a section of a filter bed
provided with a central inlet pipe constituting a down passage for conducting the
sewage to be filtered to the lower part of the filter into which pipe the sewage is
delivered from above so that air is carried with it into the said pipe. Referring to
the said figure is the bed of iltering material which is supported above the
bottom of the chamber in which it is placed by a perforated floor g. h is the
down passage the bottom of which is provided with a spreader 4* and is a pipe
from which sewage passes to the said passage h. jj are pipes placed in the filter
bed which pipes admit of the escape of air accumulating in the filter bed and
which would otherwise be confined within the said bed. The said pipes may be
branched and may be furnished with valves at their upper ends to prevent escape
of air when no accumulation thereof in the bed occurs and the said pipes may be
of sufficient length to pass entirely through the filter bed and communicate with
the space beneath the perforated floor g. The arrows indicate the direction of
passage of water through the apparatus.
By dispensing with the bed of filtering material the apparatus illustrated in
Figure 11 is rendered capable of use as an aërating tank.
Where it is desirable to provide for escape of air from the passage / when very
large bubbles are carried down it I form an enlargement in the said passage h at
some distance from its upper end and mount in the said passage a tube the upper
end of which projects above the upper end of the said passage and the lower end
of which is expanded and is situated within the enlargement in the passage h.
This arrangement is illustrated in Figure 12 in which figure the enlargement in
the pass his marked and the air escape pipe is marked l.
Where gases other than air are required to be passed into the apparatus with
the sewage this may be provided for by closing the upper end of the passage à
and conveying the required gases and the sewage into the said passage by means
of pipes opening within it as illustrated in Figure 13 in which figure the pipe for
conveying gases to the said passage is marked m.
For the purpose of prolonging contact of the air or gas with the liquid under
treatment in some cases form the down passage (which is marked in Figure 11)
as illustrated in elevation in Figure 14 or as illustrated in plan in Figure 15 in
each of which figures the inlet is marked n and the outlet o or otherwise form
the said down passage suitably for the said purpose.
As a modification I sometimes work the aforesaid aërating tubes as a syphon
and provide each end with a valve (in order to be able to charge the syphon) and
a water seal the sewage flowing first upwards and then downwards. The up tube
in this case is preferably the larger and I sometimes provide it with a restricted
inlet neck. The air is dashed or blown into the water seal of the up tube or into
the up tube itself.
Figure 16 of the accompanying drawings is an elevation of an arrangement
suitable for working aerating apparatus of the kind hereinbefore described by
syphon action. Referring to the said figure p is the syphon are vessels into
'

page_text: which the legs of the syphon descend and which act as seals is the inlet for the
liquid to be treated. The arrows indicate the direction in which the liquid passes.
Where gas other than atmospheric air is to be introduced into the liquid entering
the vessel g without blowing or forcing the same into the liquid I close the mouth
of the water seal and connect thereto conduits for conveying to it the liquid to
be purified and the gas with which the said liquid is to be charged as shown in
Figure 13. The liquid passing from the vessel may be dealt with in any way as
before mentioned for aërated liquid. No means for charging the syphon are
shown in the drawing but it will he understood that any known means may be
used.
A further head of the second part of my invention consists in forcing air into a
filter bed or drawing air out of a filter bed by the following method :—
I provide one or more airtight receptacles which for convenience of reference I
will call the air tube furnished with inlet or inlets and outlet or outlets both for
the sewage and for the air into which the sewage first flows and then flows
out the number of the said air tubes I prefer to use is three each said nir
tube is provided with an inlet and outlet for the sewage and an inlet and outlet for
the air suitable valves or arrangement being provided so that the sewage shall flow
into one said air tube which when full shall commence to run off the sewage
meanwhile passing into another air tube which in its turn shall fill and empty and
so on for each said air tube provided the inlet or outlet for the air to and from the
said air tube is connected with the filter bed suitable valves or arrangement being
interposed so that the air or gas forced out of the said air tube when the tube is
filling is either passed into the filter bed and the air or gas required to fill the
said air tube when the sewage is passing therefrom is drawn from the atmosphere
or from some other supply of suitable gas or the air or gas required to fill the said
air tube when the sewage is passing therefrom is drawn through the filter bed and
discharged into the atmosphere when the said air tube is filling with sewage in this
latter case the gas drawn through the filter bed may be taken from a supply of any
suitable gas instead of from the atmosphere. I may employ oxygen or ozone or
carbonie oxide or sulphurous acid gas or other gas.
"
I preferably arrange the various valves or the like to work automatically.
Apparatus arranged as and for the purpose herein before described is illustrated
in vertical section in Figure 17 of the accompanying drawings. Referring to the
said figure is the airtight receptacle or chamber hereinbefore termed the "air
tube s is the sewage inlet which is furnished with a lever valve capable of
being opened and closed automatically by the action of a float a weight and
knob connected by a cord y passing over a pulley and through a hole in the
valve lever. The sewage outlet consists of a syphon 1. 2 is the air passage which
is furnished with an outwardly opening valve 3 and an inwardly opening valve 4
which later valve covers the mouth of a pipe 5 by which the air passage 2 may be
connected to a filter bed so as to cause air or other gas to be drawn through the
said bed into the chamber when the sewage is passing out of the apparatus.
In the drawing the valve lever and the arrangement for actuating it are shown
in the positions which they occupy when sewage has passed into the chamber to
a sufficient height to cause action of the discharging syphon 1 to begin. During
the continuance of discharge the valve 4 is automatically kept open by indraught
of air through the branch 5 and the float descends as the level of the sewage
descends until the knob bears on the valve lever the valve being thereby opened
and a further quantity of sewage admitted to the chamber r. During the inflow of
sewage the pressure of air escaping from the said chamber closes the valve 4 and
opens the valve 3.
τ
Where air or other gas is to be forced through a filter bed by means of
apparatus of the kind herein before described the branch 5 is open to the air or is
connected to the supply of the required gas and the air passage 2 is connected to a
pipe communicating with the filter.
Any number of apparatus such as that herein before described with reference to

page_text: Figure 17 may be connected to one filter bed. Unless means be provided for
passing the air in the receptacle (supposing the air to be drawn from the
filter) direct into the atmosphere or for charging the said receptacle with fresh
atmospheric air instead of with air drawn from the filter I should be only forcing
into the filter air which had been previously drawn out of it.
The mechanical details for admission and emission of the air and water may be
greatly varied for instance the parts marked 3, 4 and 5 in Figure 17 may be
dispensed with and the air passage 2 be connected with the filter bed. Or the
inlet valve t and the mechanism for actuating it may be dispensed with and
instead of a syphon I may use an arrangement to open and shut the exit pipe for
liquid from the receptacle r. For instance an arrangement similar to that
illustrated in Figure 17 for controlling inlet of the liquid may be substituted for
the syphon.
I may work the air tube by liquid either before it has been filtered or after it
I some-
has been filtered and I may use liquid from other source such as a river.
times use several air tubes or sets of air tubes arranged at different levels so that
the liquid may be caused to work more than one air tube.
When I wish to use an air tube to work by the water issuing from a filter bed
I preferably omit the valve and float arrangement shown in Figure 17 but I
require a water seal to the inlet pipe to obtain the best results and also the two air
valves.
Instead of atmospheric air I may draw or force other gas through a filter bed
for instance oxygen or ozone or carbonic acid gas or sulphur fumes or combustion
products from a fire or furnace or any mixture of gases, in forcing air into a filter
1 connect the air feed to the air tube with a supply of the required gas and in
drawing air through or out of a filter 1 connect the pipe that conveys the air to
the filter bed with the required source. In the latter case it is necessary to avoid
indraught of atmospheric air.
In the third part of my invention I may filter either upwardly or downwardly.
In filtering upwardly I provide means for drawing away the dirty or fouled
filtering material or a part or portion thereof as required from the botton part of
the filter bed and for allowing the remainder of the material to sink down in the
filter and take the place of that which has been removed, clean material being
added to the top part of the filter when necessary.
As an illustration of a method of carrying this into effect I form a chamber or
tank (which I will call the filter tank) to contain the filtering material the bottoni
part of the said filter tank being provided with a means whereby a part of its
contents can be discharged either direct from the filter tank or else into a second
chamber or receptacle (which I will call the receiving chamber) from which the
said discharged contents can be conveniently removed for instance by a belt
and cups.
The aforesaid means for discharging part of the contents of the filter chamber
into the receiving chamber may be a movable shutter or shutters or slide or slides
or a fixed grid or grids and a movable grid or grids or one or more moveable or
collapsible cones or part or parts thereof or an exit pipe or pipes provided with a
valve or valves and preferably in combination with any of the before mentioned
removal arrangements or other like or suitable arrangement or arrangements such
as a worm conveyor or conveyors may be employed to discharge the filtering
material direct from the filter tank. Moveable arms or stirrers are provided if
required sometimes interpose a suitable watertight valve between the filter tank
and the receiving chamber or between one part and another part of the said
receiving chamber.
When employ a pipe or pipes as before mentioned to remove the filtering
material the exit of the pipe preferably carried up as high as possible the
5 filtering material being forced out by the pressure of the water on top of the filter
bed, or sucked out by any suitable means or extracted by a combination of both
one end of the said pipe or pipes is arranged in the filter tank so that the filtering

page_text: material can be extracted there through as desired and the other end of the said
pipe or pipes is carried to a suitable position and discharges the filtering material
sewage being discharged at the same time the discharge may be into a suitable
receptacle which acts as a washing box and after undergoing a cleansing operation
the filtering material may be discharged or conveyed into the filter tank again.
Sewage either before or after the filtration may be used in the said cleansing
operation. When I wish to obtain pressure to force out the filtering material to a
considerable height 1 construct a deep filtering tank and place the filtering
material only in the lower part thereof thereby obtaining sufficient head for the
purpose.
One of the main features of this improved filter is that the sewage can be
delivered after filtration to almost the saine level as that at which the unfiltered
sewage is delivered to the filter.
I
The pipe or pipes for withdrawing the fouled filtering material are arranged as
most suitable. The inlet mouth of the pipe may face towards the top or the
bottom or the side of the filter bed. I may provide branch pipes attached to a
main or a number of separate pipes or one or more pipes with openings therein or
I may employ a movable pipe or pipes or any suitable combination of these.
sometimes employ agitating arms or perforated plates or grids or the like or worm
conveyors or combinations thereof I sometimes provide one or more controllable
jets or streams of sewage, or water which flow into the mouth or mouths of the
aforesaid pipe or pipes and thereby carry away or aid in carrying away the filtering
material through the said pipe or pipes. The said mouth or mouths may be either
enlarged or contracted or both I sometimes provide two exits from each of the said
pipe or pipes both provided with valves one exit being lower than the other the
lower exit can be opened first to start the extracting of the filtering material
which being achieved the higher exit can be opened and the lower one closed.
When require the filtering material to slide down an inclined surface I
sometimes provide a travelling or jigging arrangement to effect the same.
Arrangements embodying some of the improvements I have described under this
(the third) head of my invention are illustrated in Figures 18, 19, 20, 21 and 22
of the accompanying drawings in all of which figures the filter tanks or receptacles
in which the filtering material is placed are marked a the pipes for conveying
sewage to the filter beds are marked and the conduits into which the filtered
water passes are marked c.
In the arrangement shown in Figure 18 the filtering material at the lower part
of the filter bed when too dirty for use is allowed to descend into a pit d by
opening a valve or shutter e and is removed by means of the belt and cups j
mounted in the said pit.
g
The arrangement illustrated in Figure 19 is similar to that in Figure 18 except
that the bed of filtering material is supported by means of perforated discs 99* the
lower one of which is capable of being turned by means of a rod h working in a
bearing and provided with a handle j. In order to effect removal of the filtering
material at the lower part of the bed when necessary the plate 9* is turned
sufficiently to cause the perforations in it and the plate g to coincide when the said
material falls through the coincident perforations in the said plates into the space
beneath them whence after restoring the plate g* to its original position the said
material may be allowed to pass into the pit d by opening the shutter e.
arrangement for removal of the said material from the pit is the same as in
Figure 18.
The
In the arrangement illustrated in Figure 20 the filtering material is supported
by fixed bars kk and other bars which are connected by rods m m by means of
be raised to admit of descent of the filtering
which rods the said bars 11 may
material.
The arrangement illustrated in Figure 21 for removing fouled filtering material
from the lower part of a filter bed consists of a worm conveyor working iu.a
tube.o.

page_text: I may combine the arrangement 99* Figure 19 or Figure 20 or other similar
means with a filter provided with the worm conveyor o or I may substitute a belt
and cups for the said conveyor the said belt and cups working in either one or two
tubes or chambers to protect them from the filtering material. I may employ
other means than chain and cups or worm conveyor or I may use more than one of
these arrangements to each filter chamber. I sometimes dispense with the valve
or grid e and I sometimes provide an outlet from the pit d'or its equivalent or
from the conveyor or its equivalent from which liquid can flow while the removal
of the material is in operation in order to help such removal or to carry away dirt
previously accumulated in the filtering material.
I sometimes provide the sloping sides of the lower part of the filter tank or
receptacle with a jigging or travelling arrangement of a false bottom or bottoms or
of an arm or arms or the like in order to cause the filtering material to slip down
the said sides more perfectly or quicker during the operation of removing material
from the filter chamber I may use any known mechanical arrangement for the
purpose and sometimes arrange to work the same from the mechanism used to
remove the filtering material.
The water inlet pipes either with or without shields act in some degree in
helping the material to fall evenly down in the filter tank when the dirty portion
is being discharged the outlets for the water from the pipes & can be arranged so
that they will help in washing the dirt off or in causing the discharge of the
material while the same is being removed.
Figure 22 illustrates an arrangement for removing the fouled filtering material
by means of a pipe or conduit p furnished with a valve p* which pipe is contracted
at its mouth for the purpose of insuring free passage of the material after it has
entered the said pipe. are shields arranged above the inlet pipes which shields
Eupport a considerable portion of the weight of the material above and admit of
that below passing readily up the pipe when the valve p is opened. r is a
receptacle into which the material issuing from the pipe p passes which receptacle
is provided with an overflows for conducting away water and a draining outlet or
tapt and may have a false perforated bottom through which the liquid may drain
away as it is discharged. u is a pipe communicating with the portion of the filter
in which the filtered water collects to which pipe u a hose may be connected for
use in washing the filtering material withdrawn from the filter bed.
Where this arrangement is used a light filtering material such as coal granules
is preferable.
When I combine more than one discharge arrangement with a filter I shape the
bottom so as to best enable the said discharge arrangements to discharge from as
large an area as possible. For instance I form the bottom as a number of inverted
cones or pyramids, or with all the sides sloping towards one point. In Figure 22
it will be seen that there is a considerable pressure of water on the mouth of the
pipe p.
I sometimes supplement the before described means of cleaning a filter bed by a
quick flush of sewage (or water) through the filtering material or I sometimes use
a quick flush of sewage (or water) alone to effect the cleaning as hereafter
described. In carrying out this part of my invention I provide a valve or valves
for the exit of the sewage so placed and of such a size that when the same is or
are opened a sufficiently quick flush of sewage shall take place through the
filtering material to remove the accumulated dirt. I preferably filter upwards and
wash out downwards and preferably provide a head of filtered sewage on top of
the filtering material or at a higher level than the same which said head of filtered
sewage shall come into operation or use during the washing out of the filtering
material. preferably provide also a chamber or receptacle, which I will call the
flushing sewage chamber into which the sewage shall How after having been used
for the said flushing the said flushing sewage chamber serves as a precipitation
tank and is provided with means for withdrawing or passing away the precipitated
flushing sewage and with means for removing the sludge. I prefer to work the

page_text: said flushing sewage chamber as a continuous How precipitation tank so arranged
that the intermittent flushes of sewage shall push out before them the sewage from
the previous flush which said sewage shall then be clear and comparatively pure.
I sometimes add a suitable chemical agent to the said flushing sewage to aid its
treatment in the said flushing sewage chamber. I prefer to place the exit of the
said flushing sewage from the said flushing water chamber at as high a level as
possible consistent with obtaining a sufficiently rapid flush of sewage. The before
mentioned glass or glazed stoneware balls or ganules are especially suitable for
use in a filter bed which it is desired to clean by flushing.
The filtering material I use in the third part of my invention is preferably in
coarse granules or particles of for instance from about the size of coarse sand or
grit to that of gravel.
The sewage may enter the filtering material through perforations or slots in or
provided in the before mentioned slides or shutters or grids or cones or it may enter
through a pipe or pipes placed in the bottom part of the filter bed and preferably
slotted or perforated the said slots or perforations being preferably on the underside
of the said pipe or pipes or the sewage may enter in other ways.
I may use any suitable combination or combinations of any of the before
mentioned features of my invention.
Figure 23 illustrates in vertical section an upwardly acting filter provided with
arrangements admitting of the cleansing of the filtering material being effected by
downward passage of filtered liquid through it.
The arrangements for admitting the liquid to be filtered which are not shown in
the drawing may be the same as those illustrated in Figures 18, 19, 21 and 22.
Referring to the said Figure 23 a is the bed of filtering material which rests on a
grid through which the filtered liquid passes during the cleansing operation.
is a pipe communicating with a chamber (which I term the Hush water
chamber) and having a downwardly turned mouth provided with a spreader for the
purpose of causing the water passing into the chamber from the filter to be
dispersed as required in the said chamber which is required to be capable of
containing more liquid than the filter. y is an overflow channel by which water is
conveyed from the said chamber which channel, communicates with an exit pipe y*
provided with a valve. is a diaphragm arranged in the chamber and supporting
à bed of sand the object of which is merely to fill the upper portion of the
chamber..
=
In using a filter provided with the cleansing arrangements hereinbefore described
the liquid in the chamber is let off periodically by opening the valve in the
outlet whereby liquid from the filter is allowed pass into the said chamber the
said liquid carrying with it matter deposited in the filtering material during the normal
action of the filter. I may provide a water tight cover or I may entirely dispense
with a cover or top. The chamber a should be capable of holding more water than
is required for each flushing so that the flush shall force out clear settled liquid
from the last flush. The bottom of the chamber is provided with means for
removal of sludge therefrom such for instance that shown in Figure 3 of the drawings
accompanying the Specification of Patent No. 17335 of 1893. sometimes form
the chamber inside the filter tank. The grid e may be dispensed with and the
Hushing water be withdrawn through perforated or slotted conduits.
The fourth head of iny invention relates to improvements in precipitation tanks.
The first part of this fourth head relates most especially to deep circular tanks
and consists in providing such a tank with a bottom or floor constructed in the shape
of a cone the apex of the said cone pointing towards the top of the tank the base
of the said cone may either touch or be at some distance from the side of the
said precipitation tank and in the latter case the side of the said tank may be sloped
towards the said cone around the base of the said cone is placed a perforated or
slotted pipe or pipes connected to a suitable point or points outside the said tank
and provided with a valve or valves, the sludge being withdrawn through the said
pipe or pipes or the sludge may be withdrawn in other ways. I sometimes admit

page_text: or
the sewage into the said tank through an opening or openings at the top or at the
sides or at both the top and the sides of the said cone and when the sewage inlet
conduit passes through the said cone I sometimes provide a connection
connections from the said inlet conduit at a point about half way up the cone or at
other suitable point or points to the body of the said tank so that any sludge
accumulated in the said inlet conduit may pass out through the said connection or
connections the said sewage inlet conduit is itself preferably shaped like an inverted
ene this said arrangement of connection or connections from the sewage inlet
I some-
conduit to the body of the tank is applicable to any similar inlet conduit.
times use more than one cone as aforesaid on the bottom of the precipitation
tank.
Figures 24, 25 and 26 of the accompanying drawings illustrate precipitation tanks
embodying the improvements herein before described Figure 24 being a plan and
Figure 25 a vertical section of one arrangement and Figure 26 a vertical section
of another arrangement. In all the said figures the tanks are marked a the sewage
inlet and the perforated pipes through which the sludge passes from the tanks are
marked c.
Instead of constructing the bottom of the tank in the form of an annular V shaped.
channel as in Figures 24 and 25 the said bottom may be of the form of a single
cone the lower edge of which meets or nearly meets the vertical sides of the
tank.
In some cases I construct the bottom of the tank in the form of a number of
concentric shaped channels in each of which a perforated pipe is arranged for
exit of sludge.
Where the sewage passes upwardly into the tank through a central passage in the
conical bottom as illustrated in Figure 26 the outlets for the sewage instead of being
direct from the said passage may be formed in the sides of the cone near the apex
thereof as indicated in broken lines at d and outlets for sludge may be formed in the
positions indicated at e in order to admit of discharge of any heavy accumulation of
sludge in the said passage.
Tanks constructed as hereinbefore described may be provided with arrangements
other than those illustrated for removal of sludge.
Another part of the fourth head of my invention relates to improvements in the
admission of the sewage to upward flow tanks and consists in forming ridges approxi-
mately shaped in cross section over the bottom of the tank these approximately
shaped ridges are placed close together and have au opening or openings at or
about their apex the said ridges being as it were hollow the sewage enters the
hollow of the said ridges and disperses into the tank through the aforesaid opening
or openings perforated or slotted pipes are placed between the said ridges through
which the sludge is withdrawn.
Figure 27 represents a section of a portion of the bottom of a precipitation tank
having a ridged bottom in the ridges or some of the ridges of which are formed
passages for discharge of sewage into the tank two alternative forms of ridge
being shown in the said figure. ff are the ridges which may be either straight or
curved gg are channels formed therein which channels constitute the discharge
passages for the sewage which is conveyed to the said passages by means of
pipes hh. In some cases I arrange for discharge of the sewage from slotted or
perforated pipes laid in the channels 9 g. Bemoval of the sludge which collects
on the sides of and between the ridges may be provided for by means of slotted or
perforated pipes or by any other convenient means. The discharge passages gy
inay be either continuous or spaced.
The fifth part of my invention relates to a new or improved apparatus for adding
sludge or other fluid matter or fluid matters to sewage whereby the choking up of
the outlet by comparatively large pieces of suspended matter is avoided and the
flow of sludge or other fluid matter is equalized. The apparatus consists of a tank
or receptacle provided at the bottom part with an outlet conduit which is pivoted
C

page_text: or otherwise arranged so that the exit end of the outlet conduit can be raised to
about the top of the said tank or receptacle a float is provided inside the tank and
is connected by a shaped rod or tube or otherwise suitably connected to the said
outlet conduit a means for regulating the exact position of the exit end of the
outlet conduit in comparison with the position of the said float is also preferably
provided. To set the apparatus working the aforesaid tank or receptacle is charged
with sludge or other fluid matter and the exit end of the said outlet pipe is attached
to the connection to the said float so that the exit end aforesaid is slightly lower than
the level of the sludge or other fluid matter in the said tank or receptacle thus the
required amount of sludge or other fluid matter is delivered from the outlet conduit
which by means of the float maintains its relative position to the level of the
matter in the said tank or receptacle it is important that the said outlet conduit be
amply large..
Figures 28 and 29 of the accompanying drawings are elevations of the said
apparatus taken at right angles to each other a portion thereof being shown in
section in Figure 29. Referring to the said figures i is the tank the outlet conduit
of which consists of a nozzle and a pipe one end of which pipe is so con-
nected to the said nozzle that the free or outer end of the said pipe may be raised
and lowered. is the float which is secured to one end of a bent rod m the other
end of which is adjustably connected to a bracket n jointed to the said pipe k.
o is an orifice in the said pipe k near its outer end through which orifice fluid matter
contained in the tank is discharged when the apparatus is in action.
į
Having now particularly described and ascertained the nature of
invention and in what manner the same is to be performed I declare that I
my said
claim :-
1. Producing aggregation of portions of suspended matter in sewage by passing
it through a bed or layer or layers of pebbles or the equivalents thereof as a
preliminary to separation of the said matter from the liquid portion of the sewage
by subsidence or precipitation.
2. Arrangements substantially as herein before described and illustrated in
Figures 1 and 2 of the accompanying drawings for use in producing aggregation
of the portions of suspended matter in sewage.
3. Passing sewage in an upward direction through a chamber or chambers for
the purpose of producing aggregation of portions of suspended matter therein
prior to passing the sewage into a precipitation tank substantially as herein before
described.
4. A chamber constructed and divided into compartments as herein before
described and illustrated in Figures 3 and 4 of the accompanying drawings for use
in producing aggregation of suspended matter in sewage.
5. A series of chambers for use in producing aggregation of suspended matter in
sewage and deposition of the aggregated matter the several chambers of the series.
being of progressively increasing sectional area substantially
described and illustrated in Figure 5 of the accompanying drawings.
as herein before.
6. A series of chambers constructed substantially as herein before described and
severally illustrated in Figures 6, 7 and 8 of the accompanying drawings for use
in producing aggregation of suspended matter in sewage and deposition of the
aggregated matter.
7. In chambers for use in producing aggregation of suspended matter in sewage.
the construction of the wall or walls over which the sewage flows in its change
from an upward to a downward direction sufficiently below the water level to avoid
breaking up of coagulum or aggregated matter in the sewage while passing such-
walls.
8. The improvements hereinbefore described in the process of purifying sewage
which improvements consist in passing the effluent resulting from the treatment of
sewage by precipitation through a chamber of the construction herein before

page_text: described for use in producing aggregation, or aggregation and deposition,, of,
suspended matter in sewage.
9. The intermixture of gas with a liquid by forcing the required gas into the
liquid in a chamber through which the liquid is caused to pass rapidly downward
so that bubbles of the gas are carried away with the liquid substantially as
hereinbefore described.
10. The intermixture of gas with a liquid by directing the liquid into a conduit
in such a manner as to cause the gas to enter the liquid and be carried with it
through the conduit in the form of small bubbles substantially as hereinbefore
described.
11. The arrangement of an aërating filter bed substantially as bereinbefore
described and illustrated in Figure 11 of the accompanying drawings.
12. The arrangement hereinbefore described and illustrated in Figure 11 of the
accompanying drawings for causing intermixture of gases with liquids.
13. The arrangement herein before described and illustrated in Figure 13 of the
accompanying drawings for causing intermixture of gases with liquids.
14. Arrangements substantially as herein before described and illustrated in
Figure 16 of the accompanying drawings for use in causing mixture of gases with
liquids while passing through a tube by syphon action.
15. Forcing or drawing air or gas through a filter bed by inflow of liquid to or
outflow of liquid from a vessel communicating therewith.
16. Arrangements substantially as herein before described for forcing or drawing
air or gas through a filter bed that is to say arrangements consisting essentially of
a vessel cominunicating with the filter bed to and from which vessel liquid is
admitted and discharged the passage of air or gas to or from the filter bed being.
caused by admission of the said liquid to and discharge thereof from the said
vessel.
17. The arrangement for forcing or drawing air or gas through a filter bed.
bereinbefore described and illustrated in Figure 17 of the accompanying
drawings.
18. The improvements hereinbefore described in upward How filters which
consist in, arrangements admitting of removal of foul filtering material from the
lower part of the filter bed.
19. The arrangement of perforated or slotted pipes or conduits in a filter bed
substantially as herein before described and illustrated in Figures 18, 19 and 21 of
the accompanying drawings for conducting thereto liquid to be filtered.
20. Arrangements for supporting filtering material in a filter and admitting of
portions thereof being allowed to descend for the purpose of removal thereof from
the filter substantially as herein before described and illustrated in Figure 19 of the
accompanying drawings.
21. Arrangements for admitting of portions of filtering material in a filter being
allowed to descend for the purpose of removal thereof from the filter substantially
as hereinbefore described and illustrated in Figure 18 of the accompanying
drawings.
22. The combination with an upward flow filter of a worm conveyor for removing
filtering material from the lower part of the filter bed substantially as herein before
described and illustrated in Figure 21 of the accompanying drawings.
23. The combination with an upward flow filter of the arrangement herein before
described and illustrated in Figure 20 of the accompanying drawings for supporting
and admitting of descent of the filtering material the said arrangement consisting
of bars connected by rods and capable of being raised to admit of descent of a
portion of the said filtering material and lowered after the required portion of
filtering material has descended.
24. The combination with an upward flow filter of travelling or jigging
arrangements substantially as herein before described for the purpose of facilitating
removal of portions of the filtering material from the lower part of the filter bed.
25. The combination with an upward flow filter of arrangements for effecting

page_text: removal of filtering material from the lower part of the filter bed substantially
as herein before described and illustrated in Figure 22 of the accompanying
drawings.
26. The combination with an upward flow filter of a chamber in communication
with the lower part thereof for the purpose of receiving liquid passed downward
through the filter bed in order to cleanse it the capacity of the said chamber being
sufficient or more than sufficient for reception of the whole of the cleansing liquid
and the said chamber being furnished with means admitting of separate withdrawal
of the cleansing liquid and of matter deposited therefrom.
27. The combination with an upward flow filter of arrangements substantially
as herein before described and illustrated in Figure 23 of the accompanying
drawings whereby the filter bed may be cleansed by downward flow of liquid
through it.
28. The construction of the bottoms of precipitation tanks substantially as
hereinbefore described with reference to Figures 24 and 25 of the accompanying
drawings.
29. The construction of the bottoms of precipitation tanks as illustrated in
Figures 24 and 25 of the accompanying drawings.
30. Arrangements for inlet of sewage to precipitation tanks substantially as
hereinbefore described with reference to and illustrated in Figure 26 of the
accompanying drawings.
31. The construction of the bottoms of precipitation tanks substantially as
illustrated in Figure 26 of the accompanying drawings.
32. Arrangements for inlet of sewage to precipitation tanks substantially as
herein before described with reference to and illustrated in Figure 27 of the
accompanying drawings.
33. Apparatus constructed and acting substantially as hereinbefore described
and illustrated in Figures 28 and 29 of the accompanying drawings for use in
adding sludge or other fluid matter to sewage.
Dated this Second day of November 1895.
F. PULLEN CANDY.