Improvements in and connected with the Purification and Filtration of Sewage and other Foul Liquids.
Year: 1889

page_text: Date of Application, 15th May, 1889
Complete Specification Left, 15th Feb., 1890-Accepted, 15th Mar.,
1890
PROVISIONAL SPECIFICATION.
Improvements in and connected with the Purification and Filtration
of Sewage and other Foul Liquids.
We, CHARLES HENRY BELOE, Engineer, and FRANK CANDY, Manufacturer, both of
4, Westminster Chambers, 7, Victoria Street, London, S.W., do hereby declare the
nature of our said invention to be as follows:-
This invention has reference mainly to those processes or systems of, and to plant or
apparatus for, treating sewage and analogous foul liquids, in which the liquids are first
subjected to a precipitating treatment, whereby solid matters are deposited and the
clarified liquid subsequently filtered, deodorized and decolourized, and rendered
practically pure; and the object of this invention is, amongst other things, chiefly to
provide a simple and efficient means and method of, and apparatus for, cleansing
filters used for purposes such as described, and a couvenient, compact, and easily
operated arrangement and construction of precipitating tanks, filters and pipes, con-
duits and valves, and mode of working same; at the same time it is to be understood
that the invention is also applicable (in whole or in part) to processes or cases in which
a precipitating treatment is not eniployed.
In processes of the kind above specified for the precipitation and filtration of sewage,
the liquid which is to be subjected to precipitation and subsequent filtration, is, if
necessary, charged and mixed with a suitable precipitant of any known kind before
being delivered into the precipitating tanks.
We will for convenience, first describe the arrangement and construction of tanks,
filters, pipes conduits and valves, according to our invention which we propose to use
for carrying out the invention as applied to the purification and filtration of sewage,
and also foul liquids which undergo similar treatment for their purification; and
further for simplicity we will describe the arrangement in multiple. In a gravitating
system we provide a plurality of precipitating tanks having a common supply conduit
by which the sewage charged with precipitant is conveyed to them, communication
between the conduit and each tank being controlled by a valve. These precipitating
tanks are provided with a floating ladder over which the sewage passes into the tank,
and by which the stream is broken up and the sewage in the tank kept undisturbed.
Also in these tanks is provided a floating device by which as much as possible of the
floating matter and scum is caught and held in the portion of the tank nearest the
iulet. The outlet consists of a floating trunk guarded by a floating dam, which pre-
vents any solid and floating matters which escape the forenamed guard device from
passing into the tank..
At a lower level than the precipitating tanks, the filter beds are located, and each
bed is constructed of separate duplex form, the two portions communicating at the
bottom by a suitable conduit or conduits. Between the precipitating tanks and the
filter bed there is provided a main communication with the precipitating tanks and
the filters by branch pipes which are provided with a valve or valves for controlling
the flow of liquids to and from same. The branch pipes from the main to the two
compartments of all the filters, enter same below the level of the filtering material,
mushroom" are
and ascension pipes provided with distributing devices, such as
provided on them.
Another main provided between the precipitating tanks and the filters, and com-
municating, with the precipitating tanks by branches serves to carry off from these
sludge, scum, and other matters, cleansing liquid and other things aud the like when
so desired; the branch pipes are each provided with a valve..
A third conduit common to all the tanks and filters and communicating by branch
conduits or pipes with each of the compartments of each filter and the precipitation

page_text: tanks, is provided between these tanks and the filters, and serves to carry the matters
passed from the filters in the process of cleaning them. Each branch pipe is provided
with a suitable valve or door for controlling the flow of liquid to the respective tanks
and filters.
A common conduit is provided in connection with the filter beds, for carrying off
the filtered effluent, a suitable valve being provided on each passage connecting the
filter and the conduit.
According to this invention the filters are cleansed by the filtered sewage effluent
from another filter or other filters; and in effecting the cleansing by this filtered
effluent it is caused to pass upwards through the filtering material carrying away with
it the deposited matter in the filtering material and also the scum from the surface
thereof.
In carrying out the cleansing in connection with the arrangement and construction
of plant or apparatus above described, I cause the filtered effluent from one compart-
ment of a filter to pass through the channel or conduit, provided in the bottom thereof,
into the other compartment up through the filtering material therein, then into the
main conduit, for carrying off the cleansing liquid and other matters above specified,
and then into any of the precipitating tanks which may be employed and couvenient.
To cause the fluids to flow through the various channels, chambers, conduits etcetera,
the various valves above specified for controlling them are closed or opened as may be
necessary.
To make the cleansing equal throughout the filters, the bottom course of material
in the bed is made of pipes or open work.
The course of the sewage through the tanks and filters is as follows:-The sewage
enters the precipitating tanks and flows over the ladder, above specified, the floating
matters being separated, as already described. When the precipitation is complete
communication is formed between the tank and one of the filter beds by means of the
pipes, valves and main specified and the liquid so far clarified by precipitation is
passed through the filter and purified; the filtered and purified effluent leaving the
filter by the main or conduit provided for it.
16
The filtering material which we prefer to employ is that now known as Polarite"
and is made and sold by the International Water & Sewage Purification Company
Limited, that is to say, a layer or course or a plurality of same of this material is or
are employed in the filters amongst other courses of sand, gravel, and other like
material, the top course being preferably sand. By the use of this material the sewage
partially purified and clarified in the precipitation tanks is rendered practically
colourless and inodorous.
It will be plain the invention herein above described may be applied (in whole or in
part) to or in connection with the purification and filtration of the other foul liquids
than sewage and it will be evident that the construction and disposition of parts of
the tanks and filters and pipes and mode of conducting and controlling the liquids are
susceptible of various modifications without departing from the spirit and scope of
the invention.
COMPLETE SPECIFICATION.
Improvements in and connected with the Purification and Filtration
of Sewage and other Foul Liquids.
We, CHARLES HENRY BELOE, Engineer, and FRANK CANDY, Manufacturer, both
of 4, Westminster Chambers, 7, Victoria Street, London, S. W., do hereby declare the
nature of our said 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 has reference to those processes or systems of, and to plant or
apparatus for, treating sewage and other foul or impure liquids, in which the liquids

page_text: are first subjected to a precipitating treatment, whereby solid matters are deposited,
and the clarified liquid, subsequently, filtered, deodorized, and decolourized, and
rendered practically pure; and the chief object of this invention is, to provide a
simple and efficient method of, and means for, cleansing filters used for such purposes,
and also to provide a convenient, compact and easily operated arrangement and
construction of filters precipitating tanks, conduits, and valves; at the same time it
is to be understood that the invention is also applicable (in part) to processes or
cases in which a precipitating treatment is not employed.
In processes of the kind above specified for the precipitation and filtration of sewage,
the liquid which is to be subjected to precipitation and subsequent filtration, is, if
necessary, charged and mixed with a suitable precipitant of any known kind before
being delivered into the precipitating tanks.
For convenience, we will first describe the arrangement and construction of tanks,
filters, pipes, conduits and valves, which we propose to use for carrying out the
invention, as applied to the purification and filtration of sewage, or other foul or
impureliquids which undergo similar treatment for their purification. In a gravitating
system we provide a plurality of precipitating tanks, having a common supply
conduit, by which the sewage, charged with precipitant is conveyed to them, com-
munication between the conduit and each tank being controlled by a valve. These
precipitating tanks are provided with a floating supply trough by which the stream
is broken up and the sewage in the tank kept undisturbed; and a floating device by
which the floating matter and scum are caught and held in the portion of the tank
nearest the inlet; the outlet consisting of an ordinary floating arm guarded by a
floating dam.
At a lower level than the precipitating tanks, the filter beds are located, and each
bed is constructed of separate duplex form, and two portions communicating at the
bottom by a suitable conduit or conduits. Between the precipitating tanks and the
filter beds there is provided a main, communicating with the precipitating tanks and
the filters by branch pipes, which are provided with a valve or valves for controlling
the flow of liquids to and from same. The branch pipes from the main to the two
compartments of all the filters, enter the same below the level of the filtering material,
and ascension pipes provided with distributing devices, such as mushroom "
provided on them.
are
Another main is provided between the precipitating tanks and the filters, and
communicates with the precipitating tanks by branches, which serve to carry off from
these, scum, cleansing liquid and other matters, when so desired. The branch pipes
are each provided with a valve.
A third conduit, between, and common to all the tanks and filters, and com-
municating by branch conduits or pipes with each of the compartments of each
filter and the precipitation tanks, is provided and serves to carry away the matters
passed from the filters in the process of cleansing them. Each branch pipe is
provided with a suitable valve or door for controlling the flow of liquid to the
respective tanks and filters.
A common conduit is provided in connection with the filter beds, for carrying off
the filtered effluent, a suitable valve being provided on each passage connecting the
filter and the conduit.
According to this Invention the filters are cleansed by the filtered sewage effluent
from another filter or other filters; and in effecting the cleansing by this filtered
effluent, it is caused to pass upwards through the filtering material, carrying away
with it the deposited matter therein and also the scum from the surface thereof.
In carrying out the cleansing in connection with the arrangement and construc-
tion of plant above described, I cause the filtered effluent from one filter tank to
pass through the channel or conduit, provided in the bottom thereof, into the other
tank, up through the filtering material therein, then into the main conduit for
carrying off the cleansing liquid and other matters and then into any of the precipi-
tating tanks which may be empty and convenient. To cause the fluids to flow through

page_text: the various channels, chambers, conduits, etcetera, the various valves, above specified,
for controlling them, are closed or opened as may be necessary.
To make the cleansing equal throughout the filters, the bottom course of material
in the bed is made of pipes or open work.
The filtering material which we prefer to employ is that known as "Polarite" and
is made and sold by the Intornational Water and Sewage Purification Company
Limited, of London; that is to say, a layer or stratum, or a plurality of same, of
this material is or are employed in the filters amongst other strata of sand, gravel, and
other like material, the top stratum being preferably sand. By the use of this
material, the sewage, partially purified and clarified in the precipitation tanks-is
rendered practically colourless and inodorous.
The above description sets forth, generally, the nature, object, and purposes of our
invention, but to make it more clear, we will now proceed to describe it with the aid
of the drawings accompanying this specification, and forming a part thereof. The
drawings, together with the following description of them, illustrate and set forth
examples of plant, connected with the purification of sewage and other foul or
impure liquids, specially designed to carry out the improvements the nature of which
has been above generally explained; while the points of novelty of our invention;
which we desire to cover by these Letters Patent, will be specifically pointed out in
the claiming clauses concluding the specification.
In the Drawings
Figure 1 is a plan, showing a complete arrangement of filters, with precipitating
tanks and their various inlet and outlet, and inter-communicating, conduits, pipes,
and valves. This Figure is shown partly in sheet 1, the remainder being shown in
sheet 2.
Figure 2 is a sectional elevation of the plant shown in figure 1, taken at line X X;
and
Figure 3 is a section of the same taken at the line Y Y.
In sheet 3 of the drawings we illustrate an arrangement of plant being a modifica-
tion of that shown on sheets 1 and 2. In this sheet of Drawings,-
Figure shows the modified arrangement, in plan;
Figure shows it in cross section at the line XX Figure 4; and
Figure 6 is a cross section through a filter tank, taken at the line Y Y Figure 4.
Another modification of the invention is illustrated on sheet 4 wherein a plurality
of filters are arranged together and adapted to take and filter sewage or other foul
or impure liquid from precipitating tanks or other source. In this arrangement,―
Figure 7 shows the filters plan;
Figure 8 is a sectional elevation of the plant shewn in Figure 7 taken at the
line X. X.; and
Figure 9 is a cross section through a filter, taken at the line Y. Y.
Throughout the views of the drawings, like letters and Figures of reference are
used to denote like, or equivalent parts, of the apparatus, wherever they occur.
With reference, in the first instance, to Figures 1, 2 and 3 of the drawings,
A designates the filters; B, are the precipitating tanks; C is the supply channel or
conduit by which the sewage or other foul liquid to be treated is conveyed to the
precipitating tanks B; D are the pipes by which the clarified liquid, resulting from
the precipitation effected in the tanks B, is conveyed from each tank B to a main, E.
common to all the tanks and filters; and F are the pipes by which the liquid from
the main E is delivered to the filtering material in the filters A.. Gis the effluent
conduit, that is; the conduit which carries away the filtered liquid from the
filters A; and H and Hare, respectively, the general and branch conduits, provided
for carrying the effluent water (and other matters carried by it), used to cleanse the
filters, back into the precipitating tanks B. I is the main, and I are branches; by
which the precipitated matter is conducted from the tanks B to the sludge well or
other receptacle.
All the above conduits and pipes are provided with valves or doors by which the

page_text: flow of fluids to the various portions of the plant, is controlled as required. For
instance, the flow of liquid to the precipitating tanks B, from the common conduit C,
is controlled by the valves c¹; the discharge from the tanks B to the main E, and
the flow from the main E to the filters through the pipes F, is controlled by the
valves d' and e', respectively. And again the flow of effluent from the filters A to
the conduit G is governed by the valves g¹, whilst the cleansing water discharge
passage thereof, to the conduit H, is controlled by the valve h¹; and communication
between the branches E' and the tanks B is controlled by the valves h². And lastly
the flow of sludge from the tanks B to the sludge main 1 is controlled by the
valves provided on the branch pipes I.
Regarding the construction of the precipitating tanks B, it will be seen in the
drawings, that they consist of inner and outer brickwork walls b', division walls,b²,
and floors 6. In the upper portions of the outer wall the conduit C is built;
and in the floor ba gutter is sunk, by which the sludge and other precipitated
matter is led to the outlet pipes I, the floor 6 being made with an incline down-
wards, ou either side, towards such gutter. The trough down which the liquid
flows on its way from the channel C to the tanks B is designated c², and is a
floating dam; by which floating matters are caught and retained on the inlet sidė
of the tanks. The liquid clarified by precipitation is carried off from the tanks
from the surface; by a floating arm d², the mouth of which is surrounded by a floating
dain 3, the arm being hinged to and working upon the pipe D at d. As the last
described three things, namely, the trough e, and dams and d³, and arm d², are all
well known devices and are commonly employed in sewage precipitating works for
the same purposes as herein employed, and consequently form, per se, no part of the
improvements according to this invention no detailed description of their construction
and functions is necessary.
:
Referring now to the construction of the filters A, it will be seen that they are
made in pairs or duplex form, one pair being arranged, and adapted to be used in
conjunction with any of the precipitating tanks, under ordinary working conditions.
The filters are constructed of outer and inner walls a', and division or end walls, 'as
the case may be, a², the walls a³ being the partition wall between the two portions
forming the filter pair, but these two portions communicate with each other at the
lower corner of the outer wall by the covered in channel at which runs from end to
end of each pair of filters. Another channel at is provided at the opposite corner of
the filter and into both these channels the liquid flows, after passing through the
filtering material above it; the two channels a intercommunicating by pipes laid
on the floor of the filter. The outer one of these channels is connected to the
effluent channel G by the passage (shown in dotted lines in Figures 1 and 2)
controlled by the valve g¹ already referred to. The channels at are ventilated by
ventilators a of ordinary construction. The channels and pipes a are made of
any suitable material, and loosely laid, so that water from the filtering material can
flow into or out of them, and the whole drainage pipes and passages are ventilated by
the ventilators. The channel a', nearest the tanks B, is provided, mainly, for the
purpose of rendering the ventilation of the pipes a effective, and simply done. The
liquid to be treated in the filter is distributed onto the surface of the filtering material
by branches and distributing mushrooms f. The walls of the filters are raised
about 12 to 18 inches above the level of the surface of the filtering material so as to
hold a sufficient head of liquid above the material, in working thein.
In the arrangement of plant set forth with reference to the Figures 1 and 2, it will
be seen, that the floor of the precipitating tanks, and the surface of the filtering
material, lie, practically, in the same horizontal plane, and are disposed relatively in
such a manner, that whilst all the comparatively clarified liquid in the tanks B can be
drawn off from thein, by the feeding arm and delivered into the filters A, the
liquid used to cleanse the filters can be caused to flow back into the tanks B. But of
course if desired this cleansing liquid and the matters washed out of the filters, may,
by suitable pipes or conduits, be carried directly away to any suitable 'outlet:"

page_text: The process of precipitation and filtration by and in the above described arrange-
ment of plant is as follows:-The sewage or other foul liquid already charged with a
precipitant enters the precipitating tanks B from the channel C, flowing to the tank
over the trough 2, the floating matters being caught and kept in the entrance side of
the tank by the floating dam 7. When in the tauk, the solid matter precipitates in
the usual way, and the then clarified liquid is drawn off by the arm d² and the pipes D
and E and delivered by two of the pipes F and mushrooms fonto, and distributed
over, the surface of filtering inaterial in a pair of filters A. It then sinks through
the filtering material P, and becomes purified, (that is, practically pure) and finding
its way into the pipes at the bottom of the filters and the channel a, then flows,
by way of the outer channel at and passage g², into the channel G, leaving the plant
a filtered and purified effluent.
The cleansing of the filters is effected as follows When a filter requires cleansing,
the effluent valve g¹ of a pair of filters A, and one of the valves c¹ on the supply
pipe F, are closed, and the valve h', of the filter whose supply valve, e', has been
closed, is opened; then the flow of liquid from the main E will enter one of the pair
of the filters by its pipes F, 1, and will pass through the material therein, and be
filtered and purified in the ordinary way, but the outlet valve g¹ of the pair being
closed, the filtered and purified effluent is caused to flow by way of the channels a
into the bottom of the other filter of that pair, and then up through the filtering
material therein to the surface thereof, washing and cleansing on its way the material,
and removing from its surface, the scum that will have lodged thereon, the washing
effluent and the matters removed by it being swept or washed out through the outlet
and open valve into the common channel H. From here it is allowed to flow, by
way of a channel H₁ and valve h², into any of the tanks B which may be empty and
ready to receive it. By this arrangement it will now be seen, a pair of filters A are
rendered self cleansing by alternately opening and closing certain valves, and they
therefore constitute, alternating self-cleansing filters. The method of cleansing filters
in the arrangements herein set forth, briefly stated, consists, in employing the
effluent produced from sewage or other foul or impure liquid by one filter, to pass
through the filtering material and remove the impurities and scum, deposited from
such sewage or foul liquid, of another filter.
The above description of the method and process of cleausing the filters applies to
all the arrangements and modifications herein illustrated.
Now with reference to the modification shown in Figures 4, 5 and 6, the main
difference between this and the arrangement above described with reference to
Figures 1 to 3, is, the substitution for the filter pipes F and mushroom distributors f²,
used in that plan, of the pipes F and open troughs. In this case the clarified
liquid from the tanks B flows by way of the pipes D, E, and F, into the troughs f¹
arranged at the inlet end and sides of the tanks, and overflowing the edges of the
troughs, distributes itself over the surface of the filtering material; it then passes
down through the material and away in the manner above described with reference
to Figures 1 to 3.
In the cleansing process in this case, the water used for the purpose, flows upwards
through the filtering material in the same manner as described with reference to
Figures 1 to 3, but Hows off from the surface, by the central gutter or channel h
in the filtering material, the surface of which is inclined downwards towards the
centre gutter, and also towards the outlet into the channel H. By this means the
scum and other matters are washed off or swept from the material more effectively
than by the arrangement shown in Figures 1 to 3.
With regard to the modified arrangement shown in Figures 7, 8 and 9, this plan
is one in which two series of filters, in pairs, are arranged side by side and the liquid
to be purified is conveyed to them by pipes or conduits from a separate arrangement
of precipitating tanks, or any other source. It will be seen upon reference to the
drawings, that this arrangement of filters is practically the same as that, shown in
Figures 1 to 3, and 4 to 6. The construction of the filters in this case is that

page_text: described with reference to and shown in Figures 4 to 6, with this exception,-that in
this case, in lieu of the troughs, being arranged on about the same level as the
surface of the filtering material, as shown in those figures, they are, in this arrange-
ment, disposed considerably above the level of the surface of the filtering material.
In this modification the scum and cleansing liquid used for cleansing the filters is
carried away by the channel H to the sludge pit, or other point of deposit. In other
respects than these just specified, namely, as regards construction, operation, and
process of cleansing, the methods and plans described with reference to Figuresi to 3,
aud 4 to 6, are employed in this arrangement.
Having now fully described, and illustrated by examples, the nature of our said
invention and in what manner the same is to be performed, in conclusion we desire
to remark, that in the foregoing specification we have described in connection with
the accompanying drawings, complete arranged or organized plant for the precipita-
tion and filtration of sewage or other foul or impure liquids with the various novel
features which have been generally described, and which are more particularly
pointed out in the following claiming clauses; but it will be understood that the
novel features may be employed undividedly, as well as conjointly, as they are not
necessarily dependent upon each other; they may obviously, therefore, be employed.
one or more of them, in plant for the purification and filtration of sewage and other
foul or impure liquids, which in other features, differ radically from what we have
shewn. And we also desire it to be understood that our invention is not limited to
the precise construction and arrangement of the plant illustrated or described, since
equivalent arrangements and constructions may be employed and various modifica-
tions, not altering or departing from their essential or controlling feature or
purpose, may be substituted, without departing from the spirit, purpose, or scope of
the several features of the invention. On the other hand it is to be understood that
we make no general claim to the use of precipitating tanks and filters in combination,
for the purpose of purification and filtration of sewage and other foul or impure
liquids; but what we do claim in respect of the herein described Invention is:-
1. In systems for the purification and filtration of sewage and other foul liquids,
the herein described improvement in the cleansing of the filters employed therein,
consisting in removing from said filters, impurities and scum deposited therein, from
such sewage or foul liquid, by the purified efHuent produced by said filters.
2. In systems for the purification and filtration of sewage and other foul liquids, the
herein described improvement in the working and the cleansing of the filters employed
therein, consisting in causing the filtered effluent of one filter to pass through the
filtering material of another filter; for the purposes specified.
3. The alternating self cleansing filters herein described, that is to say, filters
arranged in pairs, and in which the filtered effluent of either filter of such a pair,
may be caused to pass through the filtering material of the other, at will, for the
purpose of cleansing.
4. The cleansing of filters, used in the purification and filtration of sewage and
other foul or impure liquids, by the effluent produced or filtered in such filters; for
the purposes set forth.
5. The arrangement of precipitating tanks and filters, conduits or pipes, and valves,
substantially as described, by which intercommunication between said tanks and filters
can be made or cut off as desired; for purposes such as specified.
6. The arrangement and construction of plant substantially as set forth with
reference to Figures 1 to 3, and 4 to 6, respectively, comprising the precipitating
tanks B, fiiters A; pipes D, E, and F having valves and e¹ thereon; conduits or
channels H, H¹ having valves and thereon; and pipes I and I' having valves f¹
thereon; operating as and for the purposes described.
7. A filtering plant for use in the filtration and purification of sewage and other foul
or impure liquids, consisting of a pair of filters in communication with each other, and
provided with two sets of supply pipes, troughs, or conduits, for delivering the liquid

page_text: thereto; an outlet for the filtered effluent; and outlets for the discharge of scum and
cleausing water substantially as described.
8. The filters arranged in series, and constructed and adapted to be operated,
substantially as set forth with reference to Figures 7 to 9 of the drawings,
wherein the scum and cleansing water are conveyed to a separate, sludge pit or
other receptacle.
Dated this outsouth day of Walu 1800
CHEESBROUGH & ROYSTON,
15, Water Street, Liverpool, Applicants' Agents.