Improvements in Mechanical Purification of Effluents of Towns, Factories, and the like, and in Apparatus therefor.
Year: 1899

page_text: Improvements in Mechanical Purification of Effluents of Towns,
Factories, and the like, and in Apparatus therefor.
1. I, MARTIN MAY, Jr., of No. 33, Darmstaedterlandstrasse, Frankfurt a/Main
Germany, Leather Manufacturer, do hereby declare the nature of this invention
to be as follows:-
.
...
As is well known, the difficulties besetting the disposal of the effluents of
towns and factories increase year by year.
It is also known with what obstinancy the said effluents resist attempts at
effectual purification.
A great variety of methods of clarifying such effluents have been proposed
for overcoming these difficulties, such as by intercepting the lighter floating
solid impurities, and by allowing the heavier impurities to subside, sometimes
in combination with the use of chemicals and earths for producing artificial
deposits.
These proposed methods of clarifying however are subject to a great variety of
disadvantages. When chemical purification is employed large quantities of
sludge remain which already commence to ferment during the time of subsidence
and which resist all treatment, and choke all filters and strainers. With the
mechanical purification of fresh effluents by means of sieves or strainers, the
mechanical clearing of these from obstructions has only partially succeeded.
The present invention has for its object to completely overcome these dis-
advantages, the property possessed by such bodies to tend to deposit in layers
upon sieves or strainers being thereby utilised in an advantageous manner.
According to the present invention a revolving cylindrical sieve or strainer
is employed in such a manner, that on the one side thereof, in consequence of
hydrostatic difference of pressure between the inflowing mass and the outflowing
purified liquid, the solid constituents are deposited in the form of a layer, and
are continuously raised up by the motion of the strainer above the surface of
he liquid mass, so as to be there removed from the strainer, the cleared surface
of which then descends into the mass again.
The layer of material which is first deposited itself acts as a filter; if it is
insuited for this purpose, special materials such as peat and the like are added
whereby it may readily be made suitable to be treated in the described manner.
If the inflow takes place in an irregular manner it is necessary to regulate the
peed of rotation of the strainer in a corresponding manner; if the strainer
urns too quickly with a small supply or with a supply containing only a small
uantity of solid matter, the difference between the two levels of the liquid
ecomes too small to ensure the adhesion of the mass on the straining surface.
on the other hand the supply is greater, then too little flows off if the strainer
rns too slowly, while, a slight increase of speed increases the discharge. To
gulate this action a regulating device is combined with a float on the supply
de of the apparatus, which controls the driving mechanism in a corresponding
anner.
The accompanying drawing shews by way of example on annani

page_text: according to the present invention suited for the purification of town sewage
effluents without any previous treatment.
It consist essentially of a revolving sieve or straining drum which is partially
immersed in the effluent.
The interior is provided with an outlet for the purified liquid that penetrates
into the drum. A brush or scraper is in contact with the exterior of the drum
for removing the raised layer of solid matter.
There is no exit for the inflowing mass except through the straining drum
or over it.
of the
Fig. 1 shews a front view partly in section and Fig. 2 is a side view.
A is the straining drum, which is carired in bearings on the end wall
trough B and is rotated by a worm wheel C and worm c driven by a belt.
The straining drum may be constructed in any suitable manner, and is prefer-
ably covered with wire gauze having meshes of from 1 square millimetre to 0.25
square millimetres area. It is closed at one end and open at the other; at the
latter end a leather ring D fixed to the end wall of the trough fits against the
drum with a sliding contact and thus serves as a packing for preventing the
passage of liquid directly from the trough into the interior of the drum through
the open end. The end wall of the trough has an opening opposite the open end
of the drum and is provided with a discharge shoot d through which the liquid
that has penetrated through the straining surface of the drum flows off.
Above the drum on the descending side thereof is a revolving brush E which
is rotated by a toothed wheel e on the axis of the worm c, and is thereby made
to remove the layer of material which has collected on the drum. The brush E
passes in contact with a spring plate F which first holds back the bristles of
the brush somewhat and then allows them to spring forward so that they are
caused thereby to throw the material taken up by them on to the incline G. Any
material that may not be taken off by the brush can be removed by a scraper f
on to the incline G.
His a float which serves to regulate the speed of rotation of the drum A.
It operates by means of the rod h elbow lever K and rod k upon the belt fork L
which shifts the belt upon the conical variable speed pullies M N of known
construction, in such manner that when the float rises the belt is shifted so as to
increase the speed of the drum.
With a difference of from 30 to 40 centimetres between the levels of the
liquid respectively outside and inside the drum, the apparatus works advan-
tageously so that a drum of 1 metre diameter requires to be about one half
immersed.
The action of the apparatus is as follows.
At the point where the drum descends into the liquid a rapid flow into the
interior of the drum takes place, whereby a layer of solid deposit is effected on
the revolving straining surface, which layer serves as filtering medium for the
liquid subsequently passing through. As the drum revolves, the layer thereon
thickens until it rises up out of the liquid and is removed by the brush E, where-
upon the cleared straining surface descends into the liquid again.
By the removal of a layer, fresh material gains access to the strainer so that
the rapid action of the filter is facilitated. The mass must be thin, as if it were
in a thick condition it would cause the layer deposited on the drum to be more
or less removed again by the frictional action due to the rotation and conse-
quently the only a small quantity would be removed by the drum. Sewage
effluents are therefore treated without previous preparation beyond causing them
first to pass through a grid, the bars of which are about 30 millimetres apart.
The mass removed from the drum can readily be subjected to a subsequent
treatment of pressing and drying.
The invention can obviously be applied in variously modified ways according
to the different conditions of different effluents.
An addition of material may be necessary not only with very thin liquids but

page_text: also with very slimy ones, or such as are not sufficiently loose and porous to
allow of the requisite flow of water through the formed layer into the interior
of the drum; such additions serve to render the deposit more porous. Instead
of peat powder, sawdust, chaff, leaves, or the like can be used. It is generally
sufficient to add such material in the proportion of 0.1 per thousand.
The drum can either be horizontal or inclined towards the discharge; it may
also be of slightly conical form and outlets may be provided at each end.
The entering water can be removed by a siphon or through a hollow trunnion.
According as it may be desired to attain the solid matter as dry as possible,
or to remove as much as possible of it from the liquid, the size of the straining
drums, their speed of rotation, the admixture of other materials &c. will have
to be determined, and if necessary the water freed from the main body of the
sludge will have to be subjected to a further treatment, either in a similar
apparatus, or in a different filtering apparatus.
If the mass to be treated is of a very unequal nature, it may be subjected
to a preliminary treatment in a rag engine or similar apparatus for rendering
the solid matter of a uniform consistency.
The revolving straining drum may also be employed in such manner that it is.
placed transversely of the channel through which an effluent flows, so that as
this flows past, a portion of the liquid is withdrawn from the main body through
the drum in a clarified form, while the remainder flows onward in a somewhat
hickened condition.
When employing additions such as peat powder, it is advantageous to add
this in a well mixed condition at the descending side of the drum.
Dated this 17th day of May 1899.
ABEL & IMRAY, .
Agents for the Applicant.
improvements in Mechanical Purification of Effluents of Towns,
Factories, and the like, and in Apparatus therefor.
I, MARTIN MAY, Jr., of No. 33, Darmstaedterlandstrasse, Frankfurt a/Main,
Germany, Leather Manufacturer, 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:-
As is well known, the difficulties besetting the disposal of the effluents of
towns and factories increase year by year.
It is also known with what obstinacy the said effluents resist attempts at
effectual purification.
A great variety of methods of clarifying such effluents have been proposed
for overcoming these difficulties, such as by intercepting the lighter floating
solid impurities, and by allowing the heavier impurities to subside, sometimes
in combination with the use of chemicals and earths for producing artificial
deposits.
These proposed methods of clarifying however are subject to a great variety of
disadvantages. When chemical purification is employed large quantities of
sludge remain which already commence to ferment during the time of subsidence
nd which resist all treatment and choke all filters and strainers. With the
mechanical purification of fresh effluents by means of sieves or strainers, the
nechanical clearing of these from obstructions has only partially succeeded..
The present invention has for its object to completely overcome these dis-

page_text: advantages, the property possessed. by such..bodies to tend to deposit in layers
upon sieves or strainers being thereby utilised in an advantageous manner.
"
According to the present invention a revolving cylindrical sieve or strainer
is employed in such a manner,. that on the one side thereof, in consequence of
hydrostatic.difference of pressure between the inflowing mass and the outflowing
purified liquid, the solid constituents are deposited in the form of a layer, and
are continuously raised up by the motion of the strainer above the surface of
the liquid mass, so as to be there removed from the strainer, the cleared surface
of which then descends into the mass again.
The layer of material which is first deposited itself acts as a filter; if it is
unsuited for this purpose, special materials such as peat and the like are added
whereby it may readily be made suitable to be treated in the described manner.
If the inflow takes place in an irregular manner it is necessary to regulate the
speed of rotation of the strainer in a corresponding manner; if the strainer
turns too quickly with a small supply or with a supply containing only a small
quantity of solid matter, the difference between the two levels of the liquid
becomes too small to ensure the adhesion of the mass on the straining surface.
If on the other hand the supply is greater then too little flows off if the strainer
turns too slowly, while a slight increase of speed increases the discharge. To
regulate this action a regulating device is combined with a float on the supply
side of the apparatus, which controls the driving mechanism in a corresponding
manner.
The drawing accompanying my Provisional Specification shews by way of
example an apparatus operating according to the present invention suited for
the purification of town sewage effluents without any previous treatment.
It consists essentially of a revolving sieve or straining drum which is partially
immersed in the effluent.
The interior is provided with an outlet for the purified liquid that penetrates
into the drum. A brush or scraper is in contact with the exterior of the drum
for removing the raised layer of solid matter.
There is no exit for the inflowing mass except through the straining drum
or over it.
Fig. 1 shews a front view partly in section and Fig. 2 is a side view.
A is the straining drum, which is carired in bearings on the end wall 6 of the
trough B and is rotated by a worm wheel C and worm e driven by a belt.
The straining drum may be constructed in any suitable manner and is prefer-
ably covered with wire gauze having meshes of from 1 square millimetre to 0.25
square millimetres area. It is closed at one end and open at the other; at the
latter end a leather ring I fixed to the end wall of the trough fits against the
drum with a sliding contact and thus serves as a packing for preventing the
passage of liquid directly from the trough into the interior of the drum through
the open end. The end wall of the trough has an opening opposite the open end
of the drum and is provided with a discharge shoot through which the liquid
that has penetrated through the straining surface of the drum flows off.
Above the drum on the descending side thereof is a revolving brush E which
is rotated by a toothed wheel e on the axis of the worm c, and is thereby made
to remove the layer of material which has collected on the drum. The brush E
passes in contact with a spring plate which first holds back the bristles of
the brush somewhat and then allows them to spring forward so that they are
caused thereby to throw the material taken up by them on to the incline G. Any
material that may not be taken off by the brush can be removed by a scraper f
on to the incline G.
His a float which serves to regulate the speed of rotation. of the drum A.
It operates by means of the rod h elbow lever K and rod k upon the belt fork L
which shifts the belt upon the conical variable speed pullies M N of known
construction, in such manner that when the float rises the belt is shifted so as to
increase the speed of the drum.

page_text: With a difference of from 30 to 40 centimetres between the levels of the
liquid respectively outside and inside the drum, the apparatus works advan-
lageously so that a drum of 1 metre diameter requires to be about one half
immersed.
J The action of the apparatus is as follows.
At the point where the drum descends into the liquid a rapid flow into the
interior of the drum takes place, whereby a layer of solid deposit is effected on
the revolving straining surface, which layer serves as filtering medium for the
liquid subsequently passing through. As the drum revolves, the layer thercon
thickens until it rises up out of the liquid and is removed by the brusli E, where-
upon the cleared straining surface descends into the liquid again.
By the removal of a layer. fresh material gains access to the strainer so that
the rapid action of the filter is facilitated. The mass must be thin, as if it were
in a thick condition it would cause the layer deposited on the drum to be more
or less removed again by the frictional action due to the rotation and conse-
quently only a small quantity would be removed by the drum.
effluents are therefore treated without previous preparation beyond causing them
Sewage
first to pass through a grid, the bars of which are about 30 millimetres apart.
The mass removed from the drum can readily be subjected to a subsequent
treatment of pressing and drying.
The invention can obviously be applied in variously modified ways according
to the different conditions of different effluents.
An addition of material may be necessary not only with very thin liquids but
also with very slimy ones, or such as are not sufficiently loose and porous to
allow of the requisite flow of water through the formed layer into the interior
of the drum such additions serve to render the deposit more porous. Instead
of peat powder. sawdust, chaff, leaves. or the like can be used. It is generally
sufficient to add such material in the proportion of 0 per thousand.
The drum can either be horizontal or inclined towards the discharge; it may
also be of slightly conical form and outlets may be provided at each end.
The entering water can be removed by a siphon or through a hollow trunnion.
According as it may be desired to attain the solid matter as dry as possible
or to remove as much as possible of it from the liquid, the size of the straining
drums. their speed of rotation, the admixture of other materials &c. will have
to be determined and if necessary the water freed from the main body of the
sludge, will have to be subiected to a further treatment. either in a similar
apparatus, or in a different filtering apparatus.
If the mass to be treated is of a very unequal nature it may be subjected
o a preliminary treatment in a rag engine or similar apparatus for rendering
he solid matter of a uniform consistency.
The revolving straining drum may also be employed in such manner that it is
laced transversely of the channel through which an effluent flows. so that as
his flows past, a portion of the liquid is withdrawn from the main body through
he drum in a clarified form, while the remainder flows onward in a somewhat
hickened condition.
When employing additions such as peat powder it is advantageous to add
his in a well mixed condition at the descending side of the drum.
Having now particularly described and ascertained the nature of this inven-
on and in what manner the same is to be performed, I declare that what I
aim is:
1. A process for the separation of the liquid constituents from the sludge-like
Huents of towns, factories and the like, consisting in causing such liquid con-
ituents to penetrate through a revolving drum-sieve, which is partially immersed
the effluent and which subject to a less pressure of liquid inside than outside
bstantially as described.
2. In the process for the separation of the liquid constituents from the sludes

page_text: like effluents of towns factories and the like causing the revolving drum sieve
to raise the solid matter out of the liquid, the difference between the internal
and external liquid pressures and the degree of fluidity of the sludge being so
adjusted that a layer of solid material is deposited at bottom on the outer surface
of the drum, and is carried up thereby in order to be removed at the upper part,
substantially as described.
3. In the process for the separation of the liquid constituents from sludge-like
effluents referred to in the first claim, the method of adding loose finely divided
or porous substances to effluents of a slimy nature, in order that the deposit
formed thereby on the drum sieve may serve as filter for the liquid constituents,
substantially as described.
4. Apparatus for carrying out the method of operating referred to in the first,
second and third claims, consisting of a drum-sieve revolving in a trough, which
drum is open at one or at both ends, such open end or ends being made to fit
watertight in an opening in the end wall of the trough through which the liquid
passing through the drum flows off, while a scraper or revolving brush in contact
with the outer surface of the drum, above the level of the sludge, effects the
removal of the layer of solid matter as it accumulates, substantially as
described.
5. In apparatus such as is referred to in the fourth claim, a regulating device
consisting of a float situated in the supply conduit for the sludge, and so arranged
in connection with suitable gear for regulating the speed of rotation of the drum
sieve, that as the level of the sludge rises or falls, the float in rising or falling
with it, causes the speed of the drum to be correspondingly varied, substantially
as described. .
Dated this 27th day of Januar 1000
ABEL & IMRAY,
Agents for the Applicant.