Improvements in the Purification of Sewage and other Foul Liquids and Water by Biological means and in the Construction Arrange- ment and Working of Filters for use therein.
Year: 1899

page_text: Date of Application, 19th Aug., 1899
Complete Specification Left, 21st May, 1900-Accepted, 14th July, 1900
PROVISIONAL SPECIFICATION.
Improvements in the Purification of Sewage and other Foul Liquids
and Water by Biological means and in the Construction Arrange-
ment and Working of Filters for use therein.
I, FRANK TOMLINSON, of No. 10, Caversham Road, Kingston-on-Thames, in
the County of Surrey, Thames Conservancy Inspector, do hereby declare the
nature of this invention to be as follows:-
My invention consists of the improvements hereinafter described in the purifica-
tion of sewage and other foul liquids and water by biological means and in the
construction arrangement and working of filters for use therein in such manner
as to provide for or permit or favour propagation and growth in them of the
larger living organisms capable of effecting purification or change of condition of
sewage and other foul liquids and water in addition to the micro-organisms the
action of which has heretofore been exclusively relied on for that purpose.
In the purification according to my invention of sewage and other foul liquids
and water (hereinafter referred to generally as "liquids") first expose them to
the action of the larger living organisms (such as flies) which feed and act on
and change the condition of the impurities contained in the liquids and I sub-
sequently expose the same liquids to conditions favourable to the incubation and
growth of the ova and larvae of the said organisms and to the action of such
other living organisms as will feed and act on the said impurities in their changed
condition and I further expose the said liquids to the action in succession of a
series of such other forms of living organisms including micro organisms as will
respectively and progressively further act on the impurities in the condition in
which they are left by the organisms immediately preceding them in action.
The several kinds of living organisms by which action on the impurities con-
tained in the liquids is effected at the different stages of the purification may
be such only as will naturally be attracted to the liquids by the nature of the
impurities and will propagate therein or such as will be unavoidably conveyed
into the several beds of the filter by or with the liquids and air entering them
and be propagated therein or in addition to these artificially or otherwise incubated
or propagated organisms of kinds known to be capable of acting on the impurities
in the liquids according to the condition of such impurities may be introduced
into the liquids at suitable stages of their purification.
My improvements in the construction and arrangement and working of filters
are devised with the object of providing practically for the purification of liquids
by the means hereinbefore described.
According to the said improvements I construct and arrange the filters as herein-
after described.
The said filters are formed of a number of shallow or comparatively shallow
beds of coke-breeze or clinker ashes or burnt ballast or gravel or sand or of any
matters or things (hereinafter termed " open material") of such nature or shape
that a bed formed of them will have a large interstitial area.

page_text: These beds are arranged at different levels and the uppermost bed is exposed
to access of both air and light and the lower beds to access of air only. Provision
is made for regulating the flow of the liquids to the several beds so that the said
liquids fill the interstices of but do not rise above the open material of the first
bed and so that they never fill the whole of the interstices of the open material
of the lower beds. Provision is also made for passage of air through the upper
portion of the beds of open material when fully charged with liquids and through
the whole of the open material when the beds are not charged with liquids.
The liquids pass to the filter from distributing troughs supported on or above
the surface of the open material of the uppermost bed and from the lower part of
it they pass by an outlet or outlets discharging into a conduit by which they are
conveyed to the top of the second bed of open material. In like manner the
liquids are caused or permitted to pass or are conveyed throughout the filter from
the bottom of one bed to the top of the one next below. The provision for passage
of the liquids from bed to bed of the filter are such that air is drawn or passes
into the beds of open material with the liquids entering them.
Each of the beds is provided with means of escape of air and gases.
The size of the filter beds has such relation to the volume of liquids to be
purified that the latter will remain in contact with the open material of the said
beds for a sufficient period to admit of the required action on the impurities in
the liquids and the outlets of the beds have a greater discharging capacity than
the maximum capacity of the supply pipe or conduit through which the liquids
enter the works.
The filters constructed and arranged as hereinbefore described are provided in
duplicate and the liquids to be purified are so supplied to them that the commence-
ment of inflow to one bed of one of the duplicate filters is simultaneous or nearly so
with the commencement of outflow from the corresponding bed of the other filter.
The passage of the liquids from one to another of the beds of the filters may be
controlled by hand or by automatically acting arrangements consisting essentially
of valves connected to floats working in cisterns which floats are actuated to
operate the said valves as required by inflow of liquids to the cisterns from the
filter beds and by outflow of liquids from the said cisterns which outflow is or may
be produced by means of syphons.
Dated this Eighteenth day of August 1899.
W. T. WHITEMAN,
Agent for the Applicant.
Improvements in the Purification of Sewage and other Foul Liquids
and Water by Biological means and in the Construction Arrange-
ment and Working of Filters for use therein.
I, FRANK TOMLINSON, of No. 10, Caversham Road, Kingston-on-Thames, in the
County of Surrey, Thames Conservancy Inspector, do hereby declare the nature
of this invention and in what manner the same is to be performed to be par-
ticularly described and ascertained in and by the following statement:-
My invention consists of the improvements hereinafter described in the purifica-
tion of sewage and other foul liquids and water by biological means and in the
construction arrangement and working of filters for use therein in such manner as
to provide for or permit or favour propagation and growth or development in them
of the larger living organisms capable of effecting purification or change of con-
dition of sewage and other foul liquids and water in addition to the micro-

page_text: organisms the action of which has heretofore been regarded as that to which
the purification of the liquids is due.
In the purification according to my invention of sewage and other foul liquids
and water (hereinafter referred to generally as "liquids ") first expose them to
light and air and thus obtain the action on them of the larger living organisms
(such as flies worms and the like) which feed and act on and change the condition
of the impurities contained in the liquids and I subsequently expose the same
liquids to conditions favourable to the incubation and growth of the ova and
larvae of the said organisms and to the action of such other living organisms
as will feed and act on the said impurities in their changed condition and I
further expose the said liquids to the action in succession of a series of such other
forms of living organisms including micro-organisms as will respectively and
progressively further act on the impurities in the condition in which they are
left by the organisms immediately preceding them in action.
The several kinds of living organisms by which action on the impurities con-
tained in the liquids is effected at the different stages of the purification may be
such only as will naturally be attracted to the liquids by the nature of the
impurities and will propagate therein or such as will be unavoidably conveyed
into the several beds of the filter by or with the liquids and air entering them
and will naturally propagate therein or in addition to organisms thus naturally
present artificially or otherwise incubated or propagated organisms of kinds known
to be capable of acting on the impurities in the liquids according to the con-
dition of such impurities and of kinds known to be fatal to pathogenic and other
injurious organisms may be introduced into the liquids at suitable stages of their
purification.
My improvements in the construction and arrangement and working of filters
are devised with the object of providing practically for the purification of liquids
by the means herein before described.
According to the said improvements I construct and arrange the filters as
hereinafter described.
The said filters are formed of a number of shallow or comparatively shallow
beds of coke-breeze or clinker ashes or burnt ballast or gravel or sand or of any
matters or things (hereinafter termed " open material") of such nature or shape
that a bed formed of them will have a large interstitial area.
These beds are arranged at different levels and the uppermost bed is exposed to
access of both air and light and the lower beds to access of air only. Provision
is made for regulating the flow of the liquids to the several beds so that the said
liquids fill the interstices of but do not rise above the open material of the first
bed and so that they never fill the whole of the interstices of the open material
of the lower beds. Provision is also made for passage of air through the upper
portion of the beds of open material when fully charged with liquids and through
the whole of open material when the beds are not charged with liquids.
The liquids pass to the filter from pipes or from distributing troughs supported
on or above the surface of the open material of the uppermost bed and from the
lower part of it they pass by an outlet or outlets discharging into a conduit by
which they are conveyed to the second bed of open material. In like manner the
liquids are caused or permitted to pass or are conveyed throughout the filter
from the bottom of one bed to the one next below. The provision for passage of
the liquids from bed to bed of the filter is such that air is drawn or passes into
the beds of open material with the liquids entering them.
Each of the beds is provided with means of escape of air and gases.
The size of the filter beds has such relation to the volume of liquids to be
purified that the latter will remain in contact with the open material of the said
beds for a sufficient period to admit of the required action on the impurities in
the liquids and the outlets of the beds have a greater discharging capacity than
the maximum delivering capacity of the supply pipe or conduit through which
the liquids enter the works.

page_text: The filters constructed and arranged as hereinbefore described are provided in
duplicate and the liquids to be purified as so supplied to them that the commence-
ment of inflow to one bed of one of the duplicate filters is simultaneous or nearly
so with the commencement of outflow from the corresponding bed of the other
filter.
The passage of the liquids from one to another of the beds of the filters may be
controlled by hand or by automatically acting arrangements consisting essentially
of valves connected to floats working in cisterns which floats are actuated to
operate the said valves as required by inflow of liquids to the cisterns from the
filter beds and by outflow of liquids from the said cisterns which outflow is or
may be produced by means of syphons.
The accompanying drawings illustrate a convenient arrangement of a pair of
filters constructed according to my invention and provided with automatically
acting apparatus for effecting or controlling the supply thereto of the liquids to
be filtered and the passage of the said liquids from one to another of the several
filter beds Figure 1 being a plan view of portions of the filters and the said
apparatus Figure 2 a vertical section of the same taken on the line 1, 1 Figure 1
Figure 3 a vertical section taken on the line 2 Figure 2 looking in the direction
of the arrow X and Figure 4 a vertical section taken on the line 3 Figure 2
looking in the direction of the arrow Z.
In the following description of the said drawings the parts thereof are referred
to by the letters and figures marked thereon. The same letters and figures of
reference indicate the same parts in all the figures of the drawings.
"
The duplicate filters which are respectively marked "Series A" and "Series B
in Figures 1 and 2 consist each of four beds of open material a¹ a² 3³ a b¹ ba
63 6 confined by walls partly shown at ab the several beds of each filter being
separated from each other by floors or horizontal partitions a6a666 66 which may
consist of clay or other convenient material impermeable or practically imper-
meable to water. The uppermost bed of each filter is open to the atmosphere
and the several beds are provided with outflow pipes c¹² c³ etc6c7c8 having
discharge outlets dddd d³ do d' d furnished with valves e e e e e e e e
which are normally retained in position to close the discharge outlets by connec-
tion with levers f f f f f f f f carrying floats g¹ g² g³ g g³ 9° g² g³ work-
ing in cisterns h¹ h² h³ h h h h h which are supplied with liquid as herein-
after described and have syphons 212223242678 arranged in them for auto-
matic discharge of the liquid therefrom during working of the filters j¹² j³ j'
jare inflow pipes entering the beds aa3 a4 2 3 4 and provided with in-
lets k¹²³k each of which pipes receives liquid from the outflow pipe of
the bed next above and conveys the said liquid into the bed in which it is situated
together with air free entry of which takes place at the space between the inlets
of the inflow pipes and the outlets of the outflow pipes c¹ c2c3 c4c5c which space
is consequent on the external diameter of the former being considerably smaller
than the internal diameter of the latter. 12 13 14 15 16 are pipes permitting of
escape from the said beds a² a³ at b2 13 14 of the air so entering after it has
travelled through the interstitial spaces thereof. The cistern h¹ is connected
with the bed a¹ by means of a pipe m¹ and with the bed b' by means of a pipe m²
(see Figure 1) and the cistern his connected with the same beds by means of
pipes m m and the other cisterns are severally connected each with two of the
beds by means of pipes m³ m² m² m³ m³ m10" m¹¹ m12 m13 m² m15 m16. The
pipes m² m³ m³ m² m³ m¹ m13 and m¹5 are furnished with ball cocks not illus-
trated. n is a conduit from which the liquid to be treated passes to the filters by
pipes and troughs o¹ 02 the said pipes being furnished with valves p
connected to apparatus for automatically actuating them so as to govern flow of
liquid to the filters as required the said apparatus consisting of buckets g¹ q²
having weep holes formed in them which buckets are suspended from an oscillat-
ing beam mounted in standards ss above the conduit n to which beam the

page_text: valves p p are also connected by rods t¹ 2. u u³ are chambers in which the
buckets gqwork which chambers are furnished with outlets u³ u. Pipes vl 3
respectively communicating the one with the filter bed b₁ and the other with the
cistern are arranged so that their other ends (which are furnished with taps not
illustrated) open over the buckets q¹ q². By means of these pipes liquid passes
into the said buckets alternately during the working of the filters as hereinafter
described the effect being to admit of flow of the liquid to be treated to the two
filters alternately. I make no claim to this apparatus as of my invention.
"
The effect of the arrangements illustrated is such that at any given time
during action of the filters two of the beds of each filter are charged or being
charged with the liquid under treatment the other two being emptied or "resting
and is also such that corresponding beds of the two filters are charged and allowed
to rest alternately. Thus while the beds a¹ and a³ of the filter Series A are in
action or
being charged the alternate beds a² a of that filter are resting or being
emptied and at the same time the beds 63 of the filter series B are being
charged and the beds 6 3 of that filter are being emptied or resting.
In the following description of the action of the said arrangements I will
assume that the beds a² at of Series A and the beds b 3 of Series B are fully
charged and are on the point of emptying and that the other beds a bare
empty and on the point of being charged and that the automatically acting
apparatus by which the direction of flow of liquid from the conduit n is governed
has just actuated the valves pl p² so as to bring them to the positions illustrated
which as will be readily understood are the positions of the said valves when the
pipe is open and the pipe 2 is closed. At this juncture the cisterns
and h are charged with liquid to nearly the height of the bends of the syphons
therein the valves el e³ e6e8 of the discharge outlets 3 d6 8 of the outflow
pipes being consequently kept closed by the floats gggg and the
cisterns h h h and h are charged to such a height that action of the syphons
therein has just begun.
hi h6
The liquid to be treated passes from the conduit n by the pipe n' and trough o¹
into the bed a¹ and rises therein while liquid from the bed b¹ passes therefrom
into the bed as will be hereinafter described and the bucket q² becomes
lightened by the liquid with which it has been charged trickling out through its
weep hole. When the liquid rises in the bed a to the level of the pipes m³ m³ it
flows through those pipes into the cisterns 5 h2 (which by that time have been
emptied by the action of their syphons) until the inflow is stopped a little below
the bends of the syphons by the action of the hall cocks herein before referred
to at the discharge ends of the said pipes. The liquid flowing into the bed a¹
then continues to rise therein until it reaches the level of the pipe m¹ when it
flows through that pipe into the cistern h¹ and therefrom through the pipe 3
which discharges into the bucket 92 of the apparatus for automatically governing
the flow of liquid to be treated the tap (not illustrated) of the said pipe being
so adjusted as to allow the liquid to pass at such a rate that descent of the said
bucket which is caused by inflow of liquid thereto assisted by escape of liquid
from the bucket g' through its weep hole will not occur until the action of the
syphon has been started by rise of the liquid in the cistern h¹ due to the passage
thereto of liquid from the bed a' through the pipe m. The tilting of the beam r
produced by the fall of the bucket 2 closes the valve and opens the valve p²
the flow of liquid from the conduit n being thus diverted from the bed a¹ to the
bed of Series B the action of the apparatus of which series is similar to that
of the series A but in consequence of the flow of liquid from the supply conduit
to the two filters being alternate the action of the apparatus of corresponding
beds thereof is alternate that is to say while the top bed a¹ of series A is being
charged the top bed 61 of series B is being discharged and vice versa. The liquid
which is discharged from the cistern h¹ by the aforesaid action of the syphon i

page_text: passes therefrom into the cistern h³ causing the syphon 3 to come into action and
discharge the liquid from the said cistern. By the said discharge from the
cistern the float g is permitted to descend and the valve e to open the con-
sequence of which is that the liquid in the bed a passes therefrom through the dis-
charge outlet d' of the outflow pipe into the inflow pipe and therefrom into the
bed a carrying air with it which enters by the inlet and escapes by the pipe /¹
as the bed fills. At the time that the apparatus connected with the bed a begins
to act as described that connected with the bed also begins to act similarly
consequently by the time those actions have taken place the beds and ³ are
empty and the beds are charged with liquid. After the whole of the charge
of liquid received by the bed a¹ has passed therefrom into the bed a² and the
whole of the charge of liquid received by the bed a has passed into the bed a' and
after the bed has been fully charged from the conduit n recharging of the
bed by passage of liquid thereto from the conduit through the pipe n¹
and trough o takes place the flow of liquid which was previously passing from
the said conduit to the bed b₁ being diverted therefrom to the bed a¹ by closure.
of the valve 22 and opening of the valve p' consequent on descent of the bucket q
due to passage thereto of liquid through the pipe from the bed on rise of
liquid therein to the level of the said pipe ¹. Prior to the flow of liquid being
thus diverted from the bed to the bed a¹ the charging of the cistern h¹ to
nearly the height of the bend of the syphon i was produced by flow of liquid
thereto from the said bed 1 through the pipe m². When during the charging of
the bed the liquid therein rises to the level of the pipe m³ it flows therethrough
into the cistern until the inflow is stopped by the ball cock (not illustrated)
at the discharge end of the said pipe the level of the liquid in the said cistern h³
when the flow is so stopped being a little below the bend of the syphon . When
the liquid in the said bed a² rises to the level of the pipe mit flows there-
through into the cistern h² starting the action of the syphon 2 of that cistern
the discharge from which passes into the cistern h+ causing action of the syphon i
by which the said cistern is discharged. Through the emptying of the cistern h²
the float g² falls and the valve e² opens the consequence being that the liquid
with which the bed is charged passes through the discharge outlet of the
outflow pipe and through the inflow pipe 2 into the bed carrying air with
it as described with reference to the discharge from the bed a¹ which air escapes
by the pipe. When the liquid so passing into the bed rises to the height
of the pipe m it flows therethrough into the cistern + until the flow is stopped
by the action of the ball cock (not illustrated) on the discharge end of the said
pipe by which time the valve et will have been closed through the action of the
Hoat the level of liquid in the said cistern being then a little below the
bend of the syphon it. After the said bed has become fully charged passage of
liquid therefrom into the bed a through the discharge outlet d³ is permitted by
opening of the valve which is caused by fall of the float g³ consequent on
discharge of liquid from the cistern through the syphon the action of which
is started by rise of liquid in the said cistern due to passage thereinto of
liquid discharged by the syphon from the cistern . The action of the said
syphon thus governs the charging of the bed by liquid passing from the
bed which takes places at the same time that the charging of the bed
liquid passing from the bed a¹ is taking place. The purified liquid is discharged
from the lowermost bed at on the valve et being opened by action of the apparatus
connected with that bed as hereinbefore described with reference to the bed
and is conducted or conveyed away from the apparatus as may be desired by any
convenient means and in a similar manner the purified liquid is discharged from
The corresponding bed of the filter series B.
by
The object of the pipes m8 m10 m14m16 is to prevent rise of liquid in the
heds above the level of the said pipes occurring in the event of acci-
dental failure of action of the syphons
in consequence of accumulation

page_text: of matter therein or otherwise. In some cases I arrange the discharge ends of the
said syphons so that liquid therefrom does not pass into the cisterns
below the said pipes m³ m10 mm in such cases being the sole means by which
action of the syphons is started.
The filter beds may be of any shape in plan and of about twelve inches in
depth but they may be of greater or less depth. The number of beds which it is
desirable to use is dependent on the nature or degree of impurity of the liquids
to be treated and the degree of purity to be obtained. Thus for the treatment
of the effluent resulting from the treatment of sewage by precipitation the
number of beds in each series may be four as illustrated and for the treatment
of ordinary town sewage in order to obtain the degree of purity required by
existing river boards six beds in each series will suffice.
For the treatment of sewage of average strength the beds are preferably formed
of such capacity that the liquid to be purified will remain in contact with the
open material for a period of about four hours.
Instead of arranging the beds one above another as illustrated in the accom-
panying drawings they may be placed side by side or in other convenient rela-
tive positions according to circumstances and where in consequence of the relative
positions of the beds the liquids will not pass by gravity from one to another of
the beds any convenient provision may be made for conveying the liquids from
one bed to another.
It is necessary to exclude light from all the beds except the one of each series
into which the liquid to be treated first passes direct sunlight being fatal to
micro-organisms and it also desirable to provide against considerable changes of
temperature in the said beds great changes of temperature being detrimental to
development of both the larger organisms and micro-organisms especially during
cold weather. For exclusion of light from the beds and prevention of objection-
able changes of temperature therein a thin layer of clay or turf resting on the
open material of the beds suffices in cases where protection of the beds as required
is not provided for by arranging them one above another as illustrated.
The discharging capacity of the outlets of the beds must be not less or prefer-
ably somewhat greater than the maximum delivering capacity of the supply to
the works.
In all cases the arrangement of the apparatus connected with the supply of
liquid and the interstitial areas of the several beds relatively one to another
should be such that in the working of the filters the interstices of the open
material of the uppermost hed will be just filled and such that a portion (say a
depth of about three inches) of the open material of each of the other beds will
never be submerged. This is necessary in order that when the organisms by
the action of which purification of the liquids is produced have become what is
technically termed "sick or sewage sick" they may be able to leave the liquid
and revive instead of being killed by continued immersion in the liquids as would
be the case were the interstices of the said beds entirely occupied with the liquids.
Instead of supplying the liquids to the filters directly from a single trough as
illustrated the ordinary arrangement of distributing troughs placed on the top of
the open material may be used.
*
Supply of liquid to the filters and passage thereof from bed to bed of the
filters may be effected or controlled by hand instead of by automatically acting
arrangements as hereinbefore described.
By the provision and use of duplicate filters as described the open material of
each of the beds is exposed to the action of air each time they are discharged
without interruption of flow of the liquid to be purified.
The space between the outlets of the outflow pipes and the inlets of the inflow
pipes through which air enters when the liquids are passing from bed to bed
of the filters are convenient for insertion of artificially or otherwise incubated or
propagated organisms info any of the covered beds where this is desired.

page_text: Having now particularly described and ascertained the nature of my said
invention of "Improvements in the purification of sewage and other foul liquids
and water by biological means and in the construction arrangement and working
of filters for use therein" and in what manner the same is to be performed I
declare that I claim :-
First For purification of matters of the kinds herein before generally referred
to as "liquids" the exposure thereof to conditions conducive to or favouring or
ensuring first action on impurities therein and propagation therein of the larger
living organisms naturally capable of beneficially changing the condition of the
impurities and further incubation of the ova of such organisms and growth and
development and duration of existence of the resulting living organisms and
action thereof on the impurities and subsequently or contemporaneously action
and duration of existence of such other kinds of living organisms as are capable
of producing successively and progressively further beneficial changes in the con-
dition of the impurities substantially as herein before described
Secondly:- A filter consisting of a series of comparatively shallow beds of open
material accessible to the atmosphere and having combined therewith arrange-
ments admitting of intermittent passage either automaticaly or otherwise of liquid
under treatment from one to another of the said beds on its way through the filter
the bed into which the liquid first passes being exposed to light and the other
beds being protected from light and of such depth that a portion of the open
material of each is above the surface of the liquid therein when the filter is in
action substantially as and for the purposes hereinbefore described.
Thirdly The working of filters of the construction defined in the foregoing
claim in such a manner that alternate beds thereof are alternately in action and
out of action.
Fourthly A filter the beds of which are so arranged or are combined with
such arrangements that organisms which are destroyed by immersion or con-
tinuous immersion in liquids may remain alive in the said beds and act bene-
ficially on impurities in the said liquids during prolonged action of the filter.
Fifthly The arrangement in duplicate of filters of the construction defined
in the second claim and the supply thereto alternately of liquid to be treated
therein substantially as herein before described.
Sixthly Automatically acting apparatus constructed and arranged substan-
tially as hereinbefore described for intermittently or periodically causing passage
of liquid from one to another of the beds of filters of the construction defined in
the second claim.
Seventhly: The general construction and arrangement of filters and the com-
bination therewith of apparatus for automatically causing intermittent or perio-
dical passage of liquid from one to another of the beds thereof herein before
described and illustrated in the accompanying drawings.
Dated this Nineteenth day of May 1900.
W. T. WHITEMAN,
Agent for the Applicant.