Improvements in or relating to the Treatment or Purification of Sewage and Apparatus therefor.
Year: 1898

page_text: Date of Application, 1st Dec
4808
Complete Specification Left, 2nd Oct., 1899-Accepted, 4th Nov., 1809
Complete Specification Left, 2nd Oct., 1899-Accepted, 4th Nov., 1899
PROVISIONAL SPECIFICATION.
Improvements in or relating to the Treatment or Purification of
Sewage and Apparatus therefor.
I, CHARLES ALPHONSO ATKINSON, of 11, Tithebarn Street, Liverpool, in the
County of Lancaster, Civil Engineer, do hereby declare the nature of this inven-
tion to be as follows:--
This invention relates to the microbial method of sewage purification, in which
the purification of sewage effluent is effected by what are known as bacterio-
logical filter beds. By this process the sewage is first treated by a preliminary
breaking down of the organic matter through the agency of microbes in a coarse
filter bed, the effluent thereafter undergoing a second treatment by being sub-
jected to microbial influences in a second filter bed of much finer grain, which
offers a greatly increased surface for the display of microbial activity. This
method has hitherto required the attendance of skilled persons possessing a
proper understanding of its character, to open and close valves in order to secure
at the proper periods of time, the operations of filling, resting and emptying, as
otherwise the process is in danger of being condemned as a failure.
My invention however is designed to obviate all necessity for personal atten-
tion, and provide a series of filter beds and communicating channels with
mechanism so arranged that each filter is automatically filled, discharged after the
proper interval of time has elapsed for the due display of microbial activity, and
left empty for aëration. Also to carry on the whole of the operations from one
central place where they can be easily overlooked with a minimum of labour.
In carrying my invention into effect, the plan I prefer is to arrange a series,
(for example six), of filter beds side by side in a circle radiating round a central
distributing chamber, these beds from the nature of their arrangement increasing
in sectional area towards the outer ends. These beds are supplied with clinker,
brickbats or other substance sufficiently coarse in grain and with large interstices,
into which the air has free access to ensure the suspended solids in the sewage
getting well into the body of the bed. The size of the beds are proportioned to
the daily flow of sewage. Into the central distributing chamber, the crude
sewage is continuously fed, it being however previously passed through apparatus
to arrest the road drift or other heavy mineral or required matters. From this
central distributing chamber, conduits lead to the respective beds, a valve or
sluice being provided to each conduit which enables the sewage to flow into one
bed and then when filled to be cut off from that bed and be diverted into the
next bed and so on. The troughs which lead the sewage from this central
chamber to the bacteria beds may be branched, so as to distribute the sewage
evenly over the whole surface of the beds. In each of the bacteria beds near
where they radiate from the central chamber, is a weir over which, when the bed
is filled, the effluent flows in a thin sheet into a chamber between the weir and
the central tank. In each of these is located a float which rises as the chamber
fills, and whose ascent operates by means of any suitable mechanism the valves
or sluices aforesaid so as to cut off the supply of crude sewage, and divert its

page_text: flow into the next bacteria bed in the series. Also each float operates a controlled
valve which discharges the contents of the float chamber into the channel leading
to the fine beds hereafter described, and the emptying of this chamber causes
its float to descend at a given rate, its descent commencing to operate a discharg-
ing sluice so arranged that after this sewage has been in the bed for about two
hours undergoing the preliminary breaking-down of the organic matters through
the agency of the microbes, this sluice comes into operation and the effluent
from the bed emptied through pipes directly into one of a series of bacteria beds
arranged concentrically around the first series, in which it undergoes a second
treatment similar in character to the first, except that the material of which the
bed is composed is of much finer grain. This second series of beds is somewhat
below the level of the first series, and is connected with a float chamber at the
centre. In these second beds the effluent is allowed to stand for about two hours
or so, after which it is drained off automatically at the centre by a discharging
sluice connected with each bed, each sluice is operated by a float in a float chamber
similar to that already described with this exception that the filling of the float
chamber will be controlled so that the float will only commence to operate the
sluice about two hours after the fine bed is filled. Each discharging sluice afore-
said is formed with an opening which is in shape like an inverted V, the sluice
door being arranged to open downwards so that the apex of the V opening shall
open first and thus cause the discharge to commence at a point higher than the
bottom of the filter bed and at a slow rate, the rate of discharge increasing and the
level of the discharge descending as the sluice door descends. In order to effect a
thorough mingling or mixing of the effluent and avoid drawing the bottom
water first and the contents of the conduit or drain, I cause the whole of the
sewage in the filter to pass downwards to the bottom of each bed before it can
possibly pass away to the discharge conduit or drain, and then rise again to the
opening of the sluice. This is effected by providing a solid wall at the bottom
of each bed and immediately beyond it a wall with openings below, the top of
which openings are below the top of the solid wall leaving a space so that the
effluent can pass under the openings in the wall and over the top of the low
solid wall, the drain or conduit provided in the bottom of the bed coming into
operation when the sluice has descended below its mouth, thus ensuring the
entire emptying of the bed. The low solid wall however might if desired be dis-
pensed with, or if desired several pairs of walls may be provided alternating
with each other throughout the bed.
Instead of the discharging sluice, I may use a timed siphon or other suitable
apparatus which will discharge the contents of the beds after the lapse of a
given interval of time.
In action therefore the crude sewage is fed into the central distributing
chamber, and from that fills one of the first series of bacteria beds. When full,
the automatic valve diverts the flow into the next bed and so on. The sewage
having been allowed to stand in each bed consecutively for about two hours to
allow time for the removal of effete organic matter through the agency of the
living organisms, the effluent is automatically discharged by the arrangement
described from the centre into the second or fine beds through a conduit provided
for the purpose. Here it is again acted upon by microbial organisms, and the
effluent finally caused to flow back into another central chamber from which it
is discharged direct onto the land or elsewhere, or the increase of purity due to
the second treatment is so marked that the effluent can even be discharged into a
stream. The treatment goes on in each bed consecutively, and thus renders the
system continuous in its action, while the whole of the operations takes place
from one central place where they can be easily overlooked.
I have described my invention more particularly in connection with the
Dibdin process, but it is obvious that it is equally applicable to other bacterio-
logical systems, or combined chemical precipitation and filtration systems or
chemical precipitation systems only. Furthermore the fine beds, instead of being

page_text: arranged concentrically as described may be arranged to radiate from the centre
the same as the coarse beds, the fine beds in that case alternating with the
coarse beds, or they may be arranged to form a parallelogram or in any other way
so long as they surround a common centre from which the operations of filling,
resting and emptying are performed.
The central outlet chamber into which each fine bed dscharges its effluent,
may be formed with an annular trough or channel, the inlets discharging into
this annular trough tangentially, this trough having an outlet, the entrance to
which is arranged tangentially opposite to the flow of the effluent. This outlet
conveys the effluent to the land or other point of discharge.
Improvements in or relating to the Treatment or Purification of
Sewage, and Apparatus therefor.
I, CHARLES ALPHONSO ATKINSON, of 11, Tithebarn Street, Liverpool, in the
County of Lancaster, Civil Engineer, do hereby declare the nature of this inven-
tion and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement : —
This invention relates to the microbial method of sewage purification, in which
the purification of sewage is effected by what are known as bacteriological filter
beds. By this process the sewage is first treated by a preliminary breaking down
of the organic matter through the agency of microbes in a coarse filter bed, the
effluent thereafter undergong a second treatment by being subjected to microbial
influences in a second filter bed of much finer grain, which offers a greatly
increased surface for the display of microbial activity. This method has hitherto
required the attendance of skilled persons possessing a proper understanding
of its character, to open and close valves in order to secure at the proper periods
the operations of filling, standing full, emptying, standing empty and refilling,
as otherwise the process is in danger of being condemned as a failure.
My invention lowever is designed to obviate all necessity for personal attention
and provide a series of filter beds and communicating channels with mechanism so
arranged that each filter is automatically filled, discharged after the proper
period of time has elapsed for the due display of microbial activity, and left
empty for aeration and refilling; also to carry on the whole of the operations from
one central place, where they can be easily overlooked with a minimum of
labour. Furthermore the unequal flow of sewage due to the variations of its
volume at different hours of the day the discharge of manufacturers' wastes, rain-
fall etc., is dealt with by my invention automatically day and night, and avoids
the almost certain failure entailed by the employment of human agency.
The invention will be understood from the following description, reference being
had to the accompanying drawings in which
Figure 1 is a plan of the filter beds, two of these beds having the feeding
conduits D and filtering material removed to show the drain conduits beneath;
Figure 2 a plan on a larger scale of the mechanism at the centre for effecting
the necessary operations;
Figure a cross section thereof on line a-b;
W $ 0
cross section on line c-d:

page_text: Figure 5 a plan on a still larger scale of part of Figure 2;
Figures 6, 7 and 8 are sectional views in detail showing the valves and operat-
ing mechanism for diverting the sewage from one filter bed to the next;
Figure 9 an elevation of the outlet valve and mechanism for operating the
same;
Figures 10 and 11 sectional elevations of same taken on opposite sides;
Referring first to Figures 1 to 5, the plan I prefer is to arrange a series (for
example six) of filter beds A side by side in a circle radiating round a central
distributing chamber B, these beds from the nature of their arrangement increas-
ing in sectional area towards the outer ends. These beds are supplied with
clinker, brickbats, stone or other substances sufficiently coarse in grain and with
large interstices, into which the air has free access, to ensure the suspended
solids in the sewage getting well into the body of the bed. The size of the beds
is proportioned to the daily flow of sewage.
Into the central distributing
chamber B the crude sewage is continuously fed, through the channel C and
pipe C, it being however previously passed through an apparatus to arrest the
road drift or other heavy mineral or required matters. From this central
distributing chamber, conduits I lead to the respective beds A, a valve or
sluice E being provided to each conduit which enables the sewage to flow into one
bed, and then when filled to be cut off from that bed and be diverted into the
next bed and so on, in the manner hereafter described. The troughs which lead
the sewage from this central chamber to the bacteria beds may be branched at d
so as to distribute the sewage evenly over the whole surface of the beds. In
each of the bacteria beds near where they radiate from the central chamber B is
a low solid wall or weir F, and downwardly projecting partitions F1 alternating
with the wall F. The effluent flows over the weir F and under the partitions Fi
into chambers A¹ A2 between the weir and the central tank B. In each of these
chambers is located a float g g' (Figures 6 and 10) which rise as the chambers
fill and descend as the chambers empty, that in A¹ operating by means of any
suitable mechanism the valves or sluices E, Figures 2, 3 and 7, which cut off
the supply of crude sewage through the conduit C and divert its flow into the next
bacteria bed in the series. This is effected by means of a rack J secured to the
float and gearing into a pinion K running loose on the shaft k but provided with
a ratchet which gears into a ratchet wheel on the shaft when the float rises,
thus turning the shaft. The rising of the float therefore turns the bevel
pinion K that in turn rotates a bevel wheel K³. This gearing is so proportioned
that the rising of the float 9 rotates the wheel K² one sixth of a revolution corre-
sponding to the number of filter beds in each series. The bevel wheel K² is
supported on a standard K³, shown in Figure 8 but omitted from
Figures 6 and 7 to avoid unnecessary repetition, and preferably
works in ball bearings as shown. This "bevel wheel K is provided
with a metallic ring L carried by hangers from the bevel wheel K
and is arranged horizontal throughout with the exception of one portion L' which
is bent upwards to form a cam. E are valve rods connected at the bottom end
to the valves E, at the other provided with rollers which ride on the metallic
ring L in such a manner that as the bevel wheel K2 is rotated, these valves are
raised and lowered by the cam L' one at a time in succession, and thus cut off the
flow of crude sewage to one bed and direct it to the next bed when the previous
bed is full. The effluent gains access from each individual bed to the chamber A¹
through the valves G, one of which is arranged in connection with each filter bed,
and supplies the chamber A¹ through the passage g². Each valve is mounted on
a hollow tube G¹ at end of which below the valve seating is the air bell G³. G³ is
an air cock, G a lever thereof and G stationary stops. As therefore the effluent
rises in the bed A a certain quantity of air is imprisoned in the air bell G and
the further rise of the effluent raises this air bell together with its valve G, and the
effluent overflows through the valve G through the passage g into the chamber A¹,
thus lifting the Hoat. The raising of the air bell G2 together with its air shaft Gi

page_text: and valve G³ brings the lever G' against one of the stationary stops G³, thus
gradually opening the valve G and allowing the imprisoned air in G³ to escape
through the tube G. When this takes place the air bell G2 falls, closing the
valve G and cutting off further supply of sewage to the chamber A' through that
particular valve. The float in the chamber A is again operated, when the next
valve G in the series is raised by the rise of effluent in another filter bed.
Also each float g g¹ operates a controlled valve H which empties or discharges
the contents of the float chambers A1 A3 into the channel I leading to the fine
beds. This is set forth so far as the float g is concerned in Figure 6, and has for its
object to enable the float to descend when it has completed its operation of
rotating the bevel wheel, and the valve G is closed. Said float is adapted to
operate the controlled valve H which discharges the contents of the float chamber
into the channel leading to the fine beds hereafter described. This valve H is
operated by means of the connecting rod hand pivoted lever h¹. On the rising of the
float therefore to the top of its stroke, it strikes against the lever h¹, thus opening
the discharge valve and allowing the float to descend. The pinion K rotates loose
on the shaft during this return movement, the ratchet riding over the teeth of
the ratchet wheel. The float is then ready for another operation, which takes
place immediately the next bed in the series is filled. The How of water into the
chamber A3 is regulated by the rise given to the conical valve T, which rise can
be regulated so as to fill the chamber in any given time corresponding to the
period during which it is intended that the beds shall remain full.
The arrangement for the chambers A2 is similar, and is set forth in Figure 10
except that the falling of the floats opens the valve T and closes the valve H and
not the rising as in the case of A¹. The valve T allows the effluent to trickle slowly
into the chamber A2 through the passage T', so as to require a period of about
two hours to fill the chamber during which period the float slowly rises, but does
not operate the shaft k. When the chamber is full, the float strikes against the
pivoted lever U which is connected with valve T and the striking against this
lever closes the valve, thus preventing any more effluent entering. The emptying
of each individual chamber A2 by valve H (which is operated in the same manner
as the valve H described in reference to Figure 6) causes the float to descend,
this descent commencing to operate its individual discharge sluice M, Figures 3,
9 and 11, after this sewage has been in the bed for about two hours undergoing the
preliminary breaking down of the organic matters through the agency of the
microbes. Thus at the proper moment the sluice comes into operation, and the
effluent from the bed is emptied through the pipes I directly into one of a series
of bacteria beds arranged as a second or fine series, in which it undergoes a second
treatment similar in character to the first, with the exception that the material
of which the bed is composed is of much finer grain. This second series of beds
is somewhat below the level of first series. In these second beds the effluent is
allowed to stand for two hours or so after which it is drained off automatically at
the centre by a discharge sluice similar to that already described in the first series.
The slow motion of each float g is communicated to its sluice M by means
of the following mechanism (see Figures 9, 10 and 11). is the shaft on which
the loose pinion K is mounted that is operated by the rack J of the float g'. This
pinion is provided with a ratchet which gears in a ratchet wheel on the shaft only
when the float is descending and thus rotates the shaft . The rotation of the
shaft turns the pinion P which gears in the quadrant P1, thus turning it slowly
into the position shown in Figure 9, and gradually opens the valve. Each
discharge sluice M is formed with openings m which are in shape somewhat like
an inverted V, the sluice being arranged to slide the segment of a circle in such
a manner that the apex of the V openings shall open first and thus cause the
discharge to commence at a point higher than the bottom of the filter bed and
at a slow rate, the rate of the discharge increasing and the level of the discharge
descending as the sluice door descends. Each of the six sluices M is constructed,
in identically the same manner, and are operated individually by a float g', the

page_text: description of one set applying equally well to the other sets. When the respective
beds are emptied, the sluice M remains open and does not close immediately so
as to allow it to drain and aerate. For the purpose of closing it after a given
interval of time, the bevel wheel K2 is provided at its under side near its periphery
with an arm Q in which is mounted a roller q. Mounted on each quadrant
shaft R is a pivoted arm R. At every movement of the bevel wheel K2 therefore,
the arm Q strikes the arm R thus turning the quadrant P back and closing the
valve, the pinion P turning loose on its shaft. The dotted lines show the
arms QR in another position.
In order to effect a thorough mingling or mixing of the effluent, and avoid
drawing the bottom water first and the contents of the drain or conduit O, I
cause the whole of the sewage in the filter to pass downwards to the bottom of each
bed, Figure 3, before it can possibly pass away to the discharge conduit or
drain and then rise again to the opening of the sluice M. This is effected as
already mentioned by providing a solid wall or weir F at the bottom of each bed
and beyond it the walls FF with openings below, the top of which openings is
below the top of the solid wall F, leaving a space so that the effluent can pass
under the openings in the walls F F and over the top of the low solid wall F,
the drain or conduit O, which is of a porous nature, provided at the bottom of
the bed coming last into operation when the sluice has uncovered its mouth,
thus ensuring the entire emptying of the bed. If desired several pairs of these
walls may be provided alternating with each other throughout the bed. Instead
of the discharge sluice M I may use a timed syphon, or other suitable apparatus,
which will discharge the contents of the bed after the lapse of a given interval of
time.
In action therefore the crude sewage is fed into the central distributing
chamber B through the conduit C and C, and from that fills one of the first or
coarse series of bacteria beds A through one of the valves E and conduits D.
When full the effluent flows through one of the valves G arranged in connection
with that particular bed and so into the chamber A where it operates through
the float the valves E, thus closing the particular valve E which fed that
particular bed and opening the next valve E in the circle, thus diverting the
How into the next bed and so on. At the same time the sewage from that particular
bed overflows into the chamber A2 filling it very slowly and its float is not brought
into operation until it has risen to the top of the chamber. It is desirable that the
sewage should be allowed to stand in each bed consecutively for about two hours
to allow time for the removal of effete matter through the agency of living
organisms, and the arrangement is therefore such that the said chamber takes
about two hours to fill. At the end of this time, the valve H opens and the float
begins to descend, thus opening the sluice M slowly and allowing the effluent to
be discharged automatically into the chamber V and from thence through the
conduit I into a second or fine series of beds provided for the purpose. Here it is
again acted upon by microbial organisms in the same manner as in the coarse
or first series, and the effluent finally discharged direct on to the land, into a
stream or elsewhere. The treatment goes on in each bed consecutively, and this
renders the system continuous in its action day and night, while the whole of the
operations take place from one central place where they can be overlooked.
I have described my invention more particularly in connection with the Dibdin
process, but it is obvious that it is equally applicable to other bacteriological
systems, or combined chemical precipitation and filtration systems, or chemical
precipitation systems only.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is:-
1. The improvement in apparatus for filtering sewage which consists in pro-
viding a central distributing chamber for the cruda sawana a series of filter bioda

page_text: side by side in a circle radiating round said distributing chamber, from which
latter the crude sewage is fed by gravity into the beds, and a central tank or
receptacle arranged below the level of the distributing chamber into which the
effluent is discharged after being acted upon in the filter beds, and from which
it flows to a second series of beds or is discharged direct on to the land or else-
where, substantially as described.
2. In apparatus for filtering sewage, the arrangement for causing the whole of
the crude sewage in the filter to pass downwards to the bottom in each bed, and
rise again before it can possibly pass away to the discharge conduit or drain,
this being effected by providing near, or on the way to, the exit sluice one or
more solid walls at bottom of each bed alternating with walls with openings
below, the top of which openings is below the top of the solid wall, leaving a
space so that the effluent can only pass under the openings in the walls and over
the top of the low solid wall, before it can pass out through the sluice, sub-
stantially as described.
3. In apparatus for filtering sewage, arranging the filter beds side by side in a
circle radiating round the central distributing chamber, these beds from the
nature of their arrangement being wedge shaped and increasing in sectional area
from the apex towards the outer ends, in combination with walls such as F and F¹
arranged in the bed for the purpose set forth and exit valves arranged at the
smaller end of each bed, whereby the effluent is crushed together as it approaches
the exit both horizontally by the wedge shaped or converging nature of the sides
of the bed, and vertically by the walls F and F substantially as described.
4. In apparatus for filtering sewage in which there are walls alternating with
each other in the bed for the purpose set forth, the combination therewith of a
drain or conduit formed of open jointed pipes provided in the bottom of the bed,
and so arranged as to drain the bottom of the bed notwithstanding the existence
of the solid walls which would otherwise prevent the bed being drained to the
bottom, in combination with a valve so arranged as to commence the discharge
at a higher point than the drain or conduit, and tend to induce the first contents
of the drain to pass upwards through the open pipe joints through the filtering
material, and mingle with the bulk of the water in the bed, substantially as
described.
5. In apparatus for filtering sewage, the combination with the filter beds of
chambers with floats so arranged that as each bed is filled the effluent flows into
the chambers and raises the floats which operate by means of suitable mechanism
the inlet sluices which divert the flow from one bed to another and the exit
sluices by which the bed is emptied after remaining full for two hours or other
required period, substantially as described.
6. In apparatus for filtering sewage, the special mechanism for operating the
exit sluice so that it shall open to discharge the effluent water after it has stood
in the bed for any required period, the said mechanism being adjustable so that
the said period and the time occupied in emptying can be varied at will, sub-
stantially as described.
7. In apparatus for filtering sewage, the combination with the filter beds of
chambers with floats, so arranged with valves, that the filling of the float chamber
will be controlled, and the float only commence to operate the exit sluice to empty
the contents of the bed after a certain period of time has elapsed, whereby suffi-
cient time is allowed for the microbial organisms to act upon the sewage, sub-
stantially as described.
8. In apparatus for filtering sewage, arranging the exit sluices of the filter
beds with one or more V shaped ports located above the bottom of the filter bed,
and so arranged that the apex of said opening shall open first and thus cause the
discharge to commence at a point higher than the bottom of the filter bed and at
a slow rate, the rate of discharge increasing and the level of the discharge
descending the wider the V shaped ports are opened substantially as described.
9. In apparatus for filtering sewage, comprising a series of filtering beds and

page_text: communicating channels, and mechanism operated by the actual flow of the
sewage and its rise and fall in the beds, so arranged that each filter is auto-
matically filled, discharged after the proper interval of time has elapsed and
left empty for aeration, substantially as described, whereby the use of hydraulic
or other devices which entail the use of extraneous power is obviated.
10. The general combined arrangement and construction of parts for con-
trolling and operating the inlet or distributing valves E, substantially as described
with reference to Figures 6 and 7 of the drawings.
11. In apparatus for filtering sewage, the special mechanism for operating the
exit sluices so that they shall respectively close the discharge orifice after the
longer possible interval of time has elapsed for draining and aeration, sub-
stantially as described.
12. The general combined arrangement and construction of parts forming my
improved apparatus for filtering or purifying sewage substantially as set forth.
Dated this 30th day of September 1899.
WM. P. THOMPSON & Co.,
Patent Agents of Liverpool, Manchester, Birmingham and London.