IMPROVEMENTS IN AND RELATING TO THE FILTRATION AND PURIFICATION OF WATER AND MEANS EMPLOYED THEREFOR to be as follows:
Year: 1884

page_text: PROVISIONAL SPECIFICATION.
I WILLIAM ROBERT LAKE, of the firm of Haseltine, Lake, and Co, Patent Agents,
Southampton Buildings, London in the County of Middlesex do hereby declare
the nature of said invention for "IMPROVEMENTS IN AND RELATING TO THE
FILTRATION AND PURIFICATION OF WATER AND MEANS EMPLOYED THEREFOR
to be as follows:-
"
The invention relates to filtration of liquids and comprises an improved method
of arresting and removing impurities liable to pass through the bed of filtering
material in the usual continuous process of filtration, by introducing into the water
simultaneously with its flow from the source of supply to the filter bed, and in
proportion to the volume of the steam, a substance which will sufficiently coagulate
the impurities to facilitate their arrest by the filter bed. It also comprises an
improved method of coagulating and arresting the impurities and of preventing
any of the coagulating agent in solution passing off with the filtered water.
According to the said method I first introduce into the water contemporaneously
with its passage into the filter, a substance which will produce coagulation, and
then a substance which will operate to precipitate the excess of the coagulant and
prevent any of the same from passing off in solution with the water, and finally
allow the water to pass through the bed of filtering material.
The said invention consists partly in introducing iron and lime into the water
prior to, or at, its entrance into the apparatus, and then allowing the water to pass
through a bed of filtering material.
The invention further comprises a method of coagulating and arresting tho
impurities and of preventing any of the coagulating material from passing off in
solution with the filtered water during a continuous process. According to this
method I introduce an alkali, an alkaline earth, or a base into the water, and then
pass the same through a filter-bed composed of comminuted iron, or comminuted
iron and sand. It also comprises a filter bed composed of comminuted metallic
iron and sand thoroughly mixed.

page_text: The filter which I prefer to employ for carrying my invention into effect consista
of a casing or tank divided by a central horizontal diaphragm or partition into two
compartments connected by a transfer washing pipe or pipes. The upper compart-
ment has an outlet for the waste water, used in washing the bed and the lower
compartment contains a bed of filtering material and is provided with an inlet for
the water to be filtered, an outlet for the purified water, and a waste pipc. In the
diaphragm a valve is provided, to permit of the return to the lower compartment
of the filtering substance after it has been transferred through the pipes into the
upper compartiment for the purpose of cleansing the same. The upper ends of the
transfer pipes are provided with suitable valves which may be opened when
the material is transferred, as described, from the lower to the upper compartment,
and may be closed after that operation has been completed.
In the base of the filter I provide cone-shaped formations of gravel, or otherwise,
the purpose of which is to direct the filtering substance downward to the mouth
of the transfer pipes during the process of washing the filter bed.
The outlet is connected with a perforated tube or tubes which pass through the
lower part of the filter bed and receive the water after the impurities have been
arrested therefrom. The water to be filtered passes into the inlet pipe from a water
meter which is of the usual kind, and which is utilized to actuate, through a
driving eccentric, a rod.
Upon the end of the said rod, opposite to that connected with the driving
eccentric, is secured a casting carrying upon its upper and lower ends pawls, and
having at its centre an elongated slot which encircles the end of the crank-
axle of an ejector. The said pawls engage the teeth of a ratchet wheel which is
rigidly affixed upon the end of the said crank axle. One of the pawls is turned to
the left and the other is turned to the right, so that when, by means of the rod the
casing receives a horizontal reciprocating motion in one direction one pawl will
first engage with the teeth and cause a rotation of the ratchet wheel and in the
other direction the other pawl will engage with the said wheel with a like result.
It will thus be seen that the said wheel receives a continuous rotary movement
corresponding with the movement of the driving eccentric, which as will be well
understood, is actuated by the flow of the water.
The ejector consists of a cylindrical casing, a crank-shaft passing centrally
through the same, and carrying a rotating cylinder, and a flexible tube or tubes
which enter the ejector at its lower portion and after encircling the inner wall bf
the casing for say a single turn, pass therefrom at a tangent to the line of its
circumference. I may employ in the ejector one or more flexible tubes according
to the material which I propose to inject into the supply pipe of the unfiltered
water as hereinafter more fully described. The flexible tube or tubes have a con-
nection with a suitable source of supply of the material which passes them into the
supply pipe for the purpose of carrying out the objects of the invention.
It will be understood that the movement of the driving eccentric is caused by the
inflow of the water; that the said driving eccentric actuates the pawls to rotate
the ratchet wheel; that the movement of this wheel rotates the crank axle and
carries the rotating cylinder against the flexible tube or tubes; that whatever
material there may be in the flexible tubes in advance of the said cylinder will be
gradually forced upward by the pressure of the same during its rotation; and that
the collapsing of the tubes, creates a vacuum following the line of the rotating
cylinder. The said vacuum will operate to draw the substance to be employed
therein from its source of supply, thus, during the rotation of the cylinder, the
material to be introduced into the water flowing through the supply pipe will be
gradually forced upward in a continuous and regular manner, and at the same time
the proper quantity of the said material will be moved into the flexible tubes to
replace that which has been ejected therefrom.
According to one method I connect one of the flexible tubes with a substance,
such for illustration, as perchloride or persulphate of iron, and then allow the
unfiltered water to pass into the water-meter. The effect of this is that the parts

page_text: of the apparatus will operate as hereinbeforo described, that during this operation
the water to be filtered will pass through the inlet pipe into the lower compartment
of the apparatus, and that contemporaneously therewith, the ejector will cause a
proper quantity of the perchloride or persulphate of iron to pass upward through
a pipe into the inlet pipe to sufficiently coagulate the impurities contained in the
water to prevent their passing through the bed of filtering substance: that is to
say the perchloride or persulphate of iron will sufficiently coagulate the impurities
to facilitate their arrest by the bed of filtering material.
After the water has passed downward through the bed of filtering material it
will escape through the outlet in a purified condition, the foreign matter having
been removed in transit. It is only necessary that a sufficient quantity of the
coagulating material be employed to effect that degree of coagulation which will
admit of the impurities being arrested by the filter bed. It is well known that in
some waters the impurities are of such a nature that they will pass through a bed
of filtering agent and escape with the water, while other foreign matter will be
arrested by the filter bed, and it is the purpose of this part of my process to
absolutely prevent any of the foreign matter, whether coarse or fine, from finding
an outlet with the water during the process of filtering.
In other methods I may use metallic iron and lime, either independently or
combined, as a coagulant and precipitant, owing to their effectiveness for the
purposes mentioned, the readiness with which they may be applied, and, also, in an
economic point of view. I prepare the iron for use by obtaining from borings, for
convenience and economy, and reducing them, by an ordinary paint mill having
burr stones, or by an attrition mill, or otherwise, to, as near as may be, an
impalpable powder. In the employment of a paint mill for this purpose the iron
should be mixed with lime and water in the proportions of, say, two parts of iron
to one part of lime and three parts of water, by weight. The iron and lime may
be pulverized while in a dry state by an attrition mill, the water being afterwards
applied to give the mass a semi-liquid consistency. The iron and lime, after having
been treated, as described, are placed in a vessel connected with a flexible pipe, of
the ejector for introduction into the inlet pipe supplying water to the filter. Too
much importance cannot be given to the value of employing iron and lime for
coagulating and precipitating the impurities, whether the said materials are
employed in a continuous process, such as that described or in a process in which
the impurities are coagulated in a tank, the liquid being afterwards passed through
a bed of filtering material.
The coagulating material, such for example as comminuted iron, and the
precipitant, as for instance, lime, may be introduced into the supply pipe either at,
or prior to, the entrance of the water into the filter, or the precipitant may be
so introduced, and the coagulant may form an element of the filter bod. In all
cases where the nature of the coagulant and precipitant will permit, they may be
combined, and thus injected through a single pipe into the water to be purified.
In instances where the precipitant and the coagulant are independently injected
into the supply pipe at, or prior to, the entrance of the liquid into the filtering
apparatus such as would be the practice when I employ sulphate of iron as it
coagulant and lime as a precipitant, I connect one of the flexible tubes with the
source of the coagulating material and the other pipe with the supply of the
precipitant, and proceed with the operation of the apparatus as herein before
described.
•
I, by preference, employ the coagulating and precipitating substances in the form
of a paste or thick syrup, the materials being ground in water and concentrated as
much as possible.
When metallic iron is employed as the coagulant, the two substances will enter
a single flexible pipe and through it be forced into the supply pipe. Any of the
iron preparations such as perchloride of iron, persulphate of iron, or sulphate of
iron, may be utilized alone as a coagulant in the filtering process, but I have found
that when lime is employed in addition thereto, a reduced quantity of the iron

page_text: may be used. When sulphate of iron is used as the coagulant it is ground with clay
and water in the proportion of about eight parts of the salt to one part of clay
and two parts of water, forming a paste, in which condition it will be ready for
introduction into the inlet pipe.
It is to be understood, that I do not confine myself to the employment of iron
or other metal and lime for coagulating and precipitating the impurities in a
filtering process, as I may use, during the filtering process, any chemical reagents
which will combine in the liquid to produce an insoluble salt and thus cause the
precipitation of the impurities.
I attain a very satisfactory result by the use of a filter bed composed of com-
minuted iron, or iron and sand, and, by means of one of the ejector-tubes
introducing lime into the supply pipe, the effect of the lime being to prevent the
iron from going into solution in the water. This process will render fhe water pure
and wholesome.
In lieu of the lime, in the process hereinbefore described, I may employ any
alkaline carbonate, or bicarbonate, or caustic alkali with good results; sulphate of
zine or chloride of zinc may also be mentioned as additional coagulants.
It will be found entirely practical and satisfactory in a great many instances to
make use of a filter bed composed of comminuted metallic iron and sand, or other
suitable inert material thoroughly mixed. I have used with good results a bed
composed of about one (1) part of iron borings or filings to about fifteen or twenty
parts, by weight, of sand or analogous material. This is about the proportions
In shallow
employed for a filter bed of Bay four or five feet in depth or more.
filters I employ an increased amount of iron. The sand and iron are thoroughly
mixed in any convenient way, and the former operates to prevent the matting or
rusting together of the iron and to attain the best results froin the combined action
of the two substances. Various materials may be employed in lieu of the sand
without departing from the nature of the invention, for instance, ground quartz or
sulphate of baryta may be substituted for the sand with good results.
As hereinl.efore described, the water meter is operated by the inflow of water,
but this is not essential in all cases, since the purified water passing from the filter
may, also, be utilized to actuate the working parts of the meter. When the water
to be filtered contains a large amount of impurities it will be found advantageous
to connect the outlet pipe for pure water with the water meter, since by so doing
any deposition of silt or the like in the meter is avoided. The meter in all cases
will, however, be connected with and operate the said rod.
Dated this 19th day of February 1884.

page_text: T, WILLIAM ROBERT LAKE, of the firm of Haseltine, Lake & Co, Patent Agents,
Southampton Buildings, London, in the County of Middlesex do hereby declare the
nature of my invention for "IMPROVEMENTS IN AND RELATING TO THE FILTRATION
AND PURIFICATION OF WATER, AND MEANS EMPLOYED THEREFOR
"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 filtration of water and comprises an improved
method of arresting and removing impurities liable to pass through the bed of
filtering material in the usual continuous process of filtration, by introducing into
the water simultaneously with its flow from the source of supply to the filter bed,
and in proportion to the volume of the stream, a substance which will sufficiently
coagulate the impurities to facilitate their arrest by the filter bed.
It also comprises an improved method of coagulating and arresting the impurities
and of preventing any of the coagulating agent in solution passing off with the
filtered water, according to which method I first introduce into the water, con-
temporaneously with its passage into the filter, a substance which will produce
coagulation, and then a substance which will operate to precipitate the excess of
the coagulant and prevent any of the same from passing off in solution with the
water, and finally allow the water to pass through the bed of filtering material.
The said invention consists partly in introducing iron and lime into the water
prior to, or at, its entrance into the apparatus, and then allowing the water to pass
through a bed of filtering material.
The invention further comprises a method of coagulating and arresting the
impurities and of proventing any of the coagulating material from passing off in
solution with the filtered water during a continuous process. According to this
method I introduce an alkali, an alkaline earth, or a base, into the water, and then
pass the same through a filter bed composed of comminuted iron or comminuted
iron and sand. It also comprises a filter bed composed of comminuted metallic iron
and sand thoroughly mixed.
In the accompanying drawing I have illustrated an apparatus for giving effect to
the process parts of my invention, which apparatus I will proceed to describe in
detail and then point out the methods by which the successful filtration of water
may be effected.
Figure 1 is an elevation of the apparatus, the filter being shewn in section ;
Figure 2 is a central vertical longitudinal section of the ejector, and
Figure 3 is a central vertical transverse section of the same.
The filter consists of a casing or tank divided by a central horizontal diaphragm
or partition A into two compartments lettered B, C, respectively, connected by the
transfer washing pipe or pipes D. The upper compartment B has an outlet E for
the waste water used in washing the bed, and the lower compartment C contains a
bed of filtering material F and is provided with an inlet G for the water to be
filtered, an outlet H for the purified water, and a waste pipe I.
In the diaphragm A, a valve J is provided to permit of the return to the lower
compartment C of the filtering substance after it has been transferred through the
pipes D into the upper compartiment B for the purpose of cleansing the same. The
upper ends of the pipes D are provided with suitable valves K which may be opened
when the material is transferred, as described, from the lower to the upper com-
partment, and may be closed after that operation has been completed.
In the base of the filter I provide cone-shaped formations of gravel or other
inaterial, the purpose of which is to direct the filtering substance downward to the

page_text: mouth of the transfer pipes D during the process of washing the filter-bed. The
outlet H is connected with a perforated tube or tubes M which passes or pass
through the lower part of the filter bed and receive the water after the impurities
have been arrested therefrom. The water to be filtered passes into the inlet pipe G
from the water-meter N which is of the usual kind, and which is utilized to actuate
through a driving eccentric O, the rod P..
Upon the end of the rod P opposite to that connected with the driving eccentric O
is secured the casting R carrying upon its upper and lower ends the pawls S, and
having at its centre an elongated slot which encircles the end of the crank-axle T of
the ejector. The pawls S engage the teeth of the ratchet-wheel V which is rigidly
affixed upon the end of the crank-axle T. One of the pawls S is turned to the left
and the other is turned to the right so that, when by means of the rod P, the
casting R receives a horizontal reciprocating motion in one direction, one pawl will
first engage with the teeth and cause a rotation of the ratchet-wheel V and in the
other direction the other pawl S will engage with the said wheel with a like result.
It will thus be seen that the said wheel receives a continuous rotary movement
corresponding with the movement of the driving excentric ○ which, as will be well
understood, is actuated by the flow of the water.
The ejector consists of the cylindrical casing W, the crank-shaft T passing centrally
through the same and carrying the rotating cylinder X and the flexible tubo or
tubes Y, which enters or enter the ejector at its lower portion as indicated at Z, and
after encircling the inner wall of the casing W for say a single turn, pass therefrom
at a tangent to the line of its circumference as indicated at a. I shall employ in the
ejector one or more tubes Y according to the material which I propose to inject into
the supply pipe of the unfiltered water as hereinafter more fully described. The
tube or tubes Y will have a connection with a suitable source of supply of the
material which passes through them into the supply pipe for the purpose of carrying
out the objects of the said invention.
It will be understood that the movement of the driving eccentric O is caused by
the inflow of the water, that the said driving eccentric actuates the pawls S to
rotate the ratchet wheel V; that the movement of this wheel rotates the crank-
axle T and carries the cylinder ✗ against the tube or tubes Y, that whatever
material there may be in the tubes Y in advance of the cylinder X will be gradually
forced upward by the pressure of the same during its rotation, and that the
collapsing of the tubes as indicated, creates a vacuum following the line of the
cylinder X. The said vacuum will operate to draw the substance to be employed
from its source of supply, thus during the rotation of the cylinder X, the material
to be introduced into the water flowing through the supply pipe G will be gradually
forced upward in a continuous and regular manner, and, at the same time, the
proper quantity of the said material will be moved into the tubes to replace that
which has been ejected therefrom..
According to one method I connect one of the tubes Y with a substance, such,
for illustration, as perchloride or persulphate of iron, and then allow the unfiltered
water to pass into the water-meter N. The effect of this is that the parts of the
apparatus will operate as heroin before described, that during this operation the
water to be filtered will pass through the pipe G into the lower compartment C of
the apparatus, and that contemporaneously therewith the ejector will cause a proper
quantity of the perchloride or persulphate of iron to pass upward through one of
the pipes b into the pipe G to sufficiently coagulate the impurities contained in the
water to prevent their passing through the bed of filtering substance F; that is to
say the perchloride or persulphate of iron will sufficiently coagulate the impurities
to facilitate their arrest by the bed of filtering material. After the water has
passed downward through the bed of filtering material it will escape through the
delivery H in a purified condition, the foreign matter having been removed in
transit. It is only necessary that a sufficient quantity of the coagulating material
be employed to effect that degree of coagulation which will admit of the impurities
being arrested by the filter bed. It is well known that in some waters the

page_text: impurities are of such a nature that they will pass through a bed of filtering agent
and escape with the water, while other foreign matter will be arrested by the filter
bed, and it is the purpose of this part of my process to absolutely prevent any of
the foreign matter, whether course or fine, from finding an outlet with the water
during the process of filtering.
In other methods I may use metallic iron and lime, either independently or
combined, as a coagulant and precipitant, owing to their effectiveness for the
purposes mentioned, the readiness with which they may be applied, and, also, in an
economic point of view. I prepare the iron for use by obtaining iron borings, for
convenience and economy, and reducing them by an ordinary paint-mill having
burr stones, or by an attrition mill, or otherwise, to, as near as may be, an impalbable
powder. In the employment of a paint mill for this purpose the iron should be
mixed with lime and water in the proportions of, say, two parts of iron to one
part of lime and three parts of water, by weight. The iron and lime may be
pulverized while in a dry state by an attrition mill, the water being afterwards
applied to give the mass a semi-liquid consistency. The iron and lime after having
been treated, as described, are placed in a vessel connected with the pipe Y of the
ejector for introduction into the pipe G supplying water to the filter. Too much
importance cannot be given to the value of iron and lime for coagulating and
precipitating the impurities, whether the said materials are employed in a
continuous process, such as that described, or in a process in which the impurities
are coagulated in a tank, the liquid being afterwards passed through a bed of
filtering material.
The coagulating material, such for example as comminuted iron, and the
precipitant, as for instance, lime, may be introduced into the supply pipe either at,
or prior to, the entrance of the water into the filter, or the precipitant may be so
introduced, and the coagulant may form an element of the filter bed, as hereinafter
described.
In all cases where the nature of the coagulant and precipitant will permit, they
may be combined, and thus injected through a single pipe Y into the water to be.
purified.
In instances where the precipitant and the coagulant are independently injected
into the supply pipe at, or prior to, the entrance of the liquid into the filtering
apparatus such as would be the practice when I employ sulphate of iron as a
coagulant and lime as a precipitant, I connect one of the tubes Y with the source
of the coagulating material and the other pipe Y with the supply of the
precipitant, and proceed with the operation of the apparatus as herein before
described.
I, by preference, employ the coagulating and precipitating substances in the
form of a paste or thick syrup, the materials being ground in water and concentrated
as much as possible.
When metallic iron is employed as the coagulant, the two substances will enter
a single pipe Y and, through it, be forced into the supply-pipe G. Any of the iron
preparations such as perchloride of iron, persulphate of iron or sulphate of iron
may be utilized alone as a coagulant in the filtering process, but I have found that
when lime is employed in addition thereto a reduced quantity of the iron may be
used.
When sulphate of iron is used as the coagulant it is ground with clay and
water in the proportion of about eight parts of the salt to one part of clay and
two parts of water, forming a paste, in which condition it will be ready for
introduction into the pipe G.
It is to be understood that I do not confine myself to the employment of iron or
other metal and lime for coagulating and precipitating the impurities in a filtering
process, as I may use during the filtering process, any chemical re agents which will
combine in the liquid to produce an insoluble salt and thus cause the precipitation
of the impurities.

page_text: I attain a very satisfactory result by the use of a filter-bed composed of com-
minuted iron, or iron and sand, and, by means of one of the ejector tubes Y,
introducing lime into the supply pipe, the effect of the lime being to prevent the
iron from going into solution in the water. This process will render the water pure
and wholesome.
In lieu of the lime in the process hereinbefore described, I may employ any
alkaline carbonate, or bicarbonate, or caustic alkali with good results; sulphate of
zinc or chloride of zine may also be mentioned as additional coagulants.
It will be found entirely practicable and satisfactory in a great many instances
to make use of a filter-bed composed of comminuted metallic iron and sand, or other
suitable inert material, thoroughly mixed. I have used with good results a bed
composed of about one (1) part of iron borings or filings to about fifteen (15) or
twenty (20) parts, by weight, of sand or analogous material. This is about the
proportions employed for a filter bed of say four (4) or five (5) feet in depth or
more. In shallow filters I employ an increased amount of iron. The sand and
iron is thoroughly mixed in any convenient way, and the former operates to prevent
the matting or rusting together of the iron and to attain the best results from the
combined action of the two substances. Various materials may be employed in lieu of
the sand without departing from the nature of the invention; for instance, ground
quartz or sulphate of baryta may be substituted for the sand, with good results.
As hereinbefore described, the water-meter is operated by the inflow of water to
the pipe G, but this is not essential in all cases, since the purified water passing
from the filter may also be utilized to actuate the working parts of the meter.
When the water to be filtered contains a large amount of impurities it will be found
advantageous to connect the outlet pipe for pure water with the water-meter, since
by so doing, any deposition of silt or the like in the meter is avoided. The meter
in all cases must, however, be connected with, and operate, the rod P.
I do not limit myself to the apparatus hereinbefore described, as it is only one of
many constructions which might be devised for carrying out the processes forming
part of the present invention. It is, however, a very desirable form by reason of
the regularity and effectiveness of its operation.
Having now particularly described and ascertained the nature of my said
Invention and the manner of performing the same I wish it understood that,
I claim
First In filtration, the method herein before described of arresting and removing
the impurities during an uninterrupted passage of water through a filter containing
a bed of filtering agent, which method consists in introducing into the water con-
temporaneously with its passage into the filter, a substance which will sufficiently
coagulate the impurities to facilitate their arrest by the filter bed; substantially as
set forth.
Second In filtration, the method hereinbefore described of coagulating and
arresting the impurities and of preventing any of the coagulating agents in solution
passing off with the filtered water, which method consists, first, in introducing into
the water prior to, or at, its entrance into the apparatus, a substance which will
produce coagulation, then a substance which will operate to precipitate the excoss
of the coagulant and prevent any of the same in solution from passing off with the
water, and finally allowing the water to pass through a bed of filtering material.
Third In filtration, the method herein before described of coagulating and
arresting the impurities and of preventing any of the coagulating material from
passing off in solution with the filtered water, which method consists in introducing
iron and lime into the apparatus, and then allowing the water to pass through a
bed of filtering material.
Fourth In filtration, the method hereinbefore described of coagulating and
arresting the impurities and of preventing any of the coagulating material from
passing off in solution with the filtered water, which method consists in introducing i
an alkali, an alkaline earth or a base into the water, and then passing the same

page_text: through a filter-bed composed of iron in comminuted form, or iron and sand or
equivalent material.
Fifth Iron and lime as a coagulent and precipitant for use in filtration.
Sixth As a means of coagulating and precipitating the impurities in filtration,
the employment of metallic iron and lime in the form of a paste.
Seventh A filter-bed consisting of metallic iron and sand or analogous material
thoroughly intermingled, substantially as, and for the purposos, set forth.
Dated this 10th day of Nawamber 1991
HASELTINE, LAKE & Co.,
For the Applicant.