Improvements in Apparatus for Purifying Water.
Year: 1896

page_text: Date of Application, 14th July, 1896-Accepted, 22nd Aug., 1896
COMPLETE SPECIFICATION.
Improvements in Apparatus for Purifying Water.
I, WILLIAM GORDON WATERMAN, Secretary of The Revolving Purifier
Company Limited, of Dock House, Billiter Street, in the City of London, do
hereby declare the nature of this invention (which has been communicated to me
from abroad by L. Alers-Hankey, of the City of New York, United States of
America,) 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 apparatus for purifying water, and particularly to
apparatus which purifies water by bringing it into contact with scrap iron, or iron
in a finely sub-divided state, such as borings, turnings, punchings or the like.
The invention consists in the novel means provided for aerating water, in the
novel receptacles provided for holding the iron by which purification is effected
and for carrying the same through the water, in the novel means employed for
obtaining a very uniform action of the apparatus, and in the novel combination,
construction and arrangement of the parts of the apparatus.
The objects of the invention are, first, to provide more efficient means for
aerating the water within the apparatus and oxidizing the ferrous salts contained
therein than has been used heretofore; second, to provide means for aerating water
which shall require less power than similar apparatus heretofore used, and which
shall be more uniform in its action; third, to provide means for securing more
uniform distribution of the iron throughout the apparatus; and fourth, to make the
apparatus simple, easy of operation and maintenance, easily charged and cleaned,
and as inexpensive as possible.
These objects are attained in the apparatus herein described and illustrated in
the drawings which accompany and form a part of this application, in which the
same reference numerals indicate the same or corresponding parts and in which:
Figure 1 is a plan view of one form of the apparatus employed for carrying out
the process; Figure 2 is a transverse section of the same;
Figure 3 illustrates a modification of the apparatus which may be used for both
purifying and elevating the water of springs and wells;
Figure 4 is a detail sectional view of the bucket used;
Figure 5 is a similar view to Figure 4, showing a modified form of bucket;
Figure 6 is a transverse elevation of another form of apparatus employing a
number of horizontal cylinders arranged about a common shaft; and Figure 7 is a
longitudinal section thereof.
In the drawings, 1 is a trough or tank which forms the vessel within which the
water is treated. At one end, near the bottom, is an induction pipe 2, and at the
other end, near the top, is an eduction pipe 3. Water enters the tank 1 through
the pipe 2 and passes out through the pipe 3 to settling tanks or filters, being acted
upon while in the tank 1 by the iron. The settling tanks are for the removal of
the coagulated and precipitated impurities.
Within the tank 1 is a longitudinal shaft 4, supported in U bearings 5, 5. In
the apparatus shown in Figures 1 and 2 there are secured to this shaft a number
of wheels 6, 6, carrying buckets 7, 7, shown in detail in Figure 4. These wheels
are preferably polygonal, as when so formed the buckets are more readily attached
thereto. The buckets are in general similar to the buckets used in any of the
ordinary forms of bucket conveyors, and may be constructed of sheet or cast metal,

page_text: manuer.
or of other suitable material. They are attached to the wheels 6 in any suitable
The mouth of each bucket is closed by a perforated plate 8, which may
be held in place by a set screw 9, as shown in Figure 4, the plate being hinged to
the bucket, or may be held in place by a bolt 10 which runs through to the back
of the bucket, as. shown in Figure 5. This plate retains within the bucket the
purifying material used, and may be removed to permit of access to the bucket for
charging or for any other reason, by unscrewing the set screw 9 or bolt 10, as the
case may be. The perforations in the plate permit of the free passage of air and
water into and out of the bucket, and since there is no opening in the back of the
bucket, (except in the form shown in Figure 5, in which the opening through
which the bolt 10 passes is sealed' by packing or other means so as to be: air tight)
when the bucket passes down into the water it will carry with it a considerable.
quantity of air, which is not liberated until the bucket has reached the bottom of.
the tank 1 and is beginning to rise.
The wheels 6 are so set upon the shaft 7 that the buckets of adjacent wheels' are
not opposite each other, but are set at slightly different angular positions, that is,.
are "staggered." In this manner the action of the apparatus is made very steady
and uniform, the water in the tank being constantly and thoroughly agitated and
treated with purifying agent.
To the shaft 4 is attached a gear wheel 11, which receives its motion from-a
pinion not shown in the drawings, but which may be conveniently mounted on a
shaft hung over the purifier. This gear wheel 11 is, as shown, inside the tank 1,
the tank being so designed and having the bearings 5 so arranged that the ends of
the shaft need not project outside of the tank. In this way stuffing boxes are
dispensed with, and the water level may be carried as high, as desired. The
bearings in which the shaft rests are not provided with caps, as the slow speed' at
which the shaft is revolved makes caps to the bearings unnecessary. The
absence of the caps to the bearings makes the removal of the shaft,, wheels, and
buckets a very simple matter, when repairs or renewals make such removal.
necessary.
Suitable hand holes may be provided in the bottom of the tank. for facilitating
the removal of sediment therefrom.
Figure 3 shows a modification: of the purifying apparatus especially designed for
wells or other locations where the water is to elevated. as well as purified. In
this case the well itself serves as the tank 1, no other tank or receptacle being
necessary. The buckets containing the purifying agent are: carried by an endless
conveyor chain 12, which runs over a sprocket wheel 13 in the bottom of the well,
and over another sprocket wheel 14 situated at a point somewhat above the level to
which the water is to be elevated. The buckets may be substantially the same as
those shown in the first form of the apparatus. When rising;, they are of course
full of water, and as they pass over the sprocket wheel 14 this. water is discharged
into a trough 15. In this form of the device the endless chain. may run at, any
desired angle from the vertical to, as a limit, the horizontal position, in which case
the apparatus would become practically equivalent to that form shown in Figures 1
and 2, but with the buckets carried on an endless chain running; longitudinally
through the tank 1 instead of on the wheels 6.
Figures 6 and 7 show another form of the apparatus in which form.horizontal
cylinders 16 are arranged about the shaft 4, and contain the charge of iron used as
a purifying agent. Each cylinder is perforated upon the side which is undermost
when it enters the water, to admit the entrance of air and water, but is imperforate
upon the upper side. The cylinders act, therefore,, in the same manner as the
buckets of the apparatus shown in Figures 1 and 2. The apparatus of Figures 6
and 7 possesses the advantage that the cylinders, being few in number, are more
readily charged than the buckets of the apparatus of Figures land. 2.
may
A greater or less number of cylinders than are shown in Figures 6 and 7 be
used, if desired. The cylinders may be provided with hoods.17 to assist. in, forcing
air into the cylinders.

page_text: The operation of all of the forms of the apparatus shown is practically identical,
and that of the first form, shown in Figures 1 and 2, will alone be described.
Before starting the apparatus in operation, the buckets 7 are charged to about
one-third of their capacity with metallic iron in the form of punchings, borings, or
chips from turning or planing machines, it being essential that the iron shall be
somewhat finely divided, and with the surfaces bright and clean.
After the charging is completed, water is admitted to the tank, until it rises to
the level of the discharge pipe, and the shaft 4 is caused to revolve slowly. As the
buckets which were below the surface of the water rise above the surface, and near
the top of the wheel, the water in these buckets flows out, and air rushes in. Since
the iron is wet, and in comparatively small particles, it is in a very favorable
condition for oxidation; and being in thorough and complete contact with the air,
the sesquioxide or the corresponding hydroxide of iron is formed. As the buckets
descend, the agitation of the particles of iron caused by the changing position of
the buckets and the attrition between the particles of iron resulting from this
agitation, causes this freshly formed oxide or hydroxide to be scraped off, and mixes
it thoroughly with the water in the buckets, where it remains, suspended in the
water in a very finely divided state, and therefore in a very favorable condition to
unite with any acids, salts, or organic impurities in the water. This it does, forming
ferrous salts, and in all probability forming ferric salts also to some extent, since the
sesquioxide of iron contains so large an amount of oxygen. As the buckets begin
to rise, the air contained therein escapes, in so doing changing any ferrous salts in
the buckets into ferric salts. When the buckets have reached the surface again,
the water therein, still charged with ferric oxide or hydroxide, flows out and mixes
with the main body of water within the tank, and this free oxide or hydroxide
unites with the impurities in the water, forming ferrous and ferric salts as before,
the ferrous salts being immediately oxidized into ferric salts by the constant stream
of air flowing upward from the buckets. The water is passed through the tank
continuously, and after passing through the tank and being treated in the manner
described, may be passed into settling tanks or over filter beds. The ferric salts,
which are insoluble, coagulate, forming a thick flocculent precipitate, which quickly
settles, leaving the water clear. In settling, the precipitate carries down with it all
earthy impurities held in suspension in the water.
Because of the coarse flocculent
nature of the precipitate, the clarification of the water by filtration, after being
treated as above described, is easily effected, inasmuch as the precipitate does not
penetrate into the filter bed, but remains on the surface, where it can readily be
removed. Hence it follows that the filter does not become clogged. In this way
the water may be freed from the precipitate very rapidly. If allowed to remain
in the settling tanks for a few hours, however, the precipitate will settle, leaving the
water quite as clear and pure as though it had been passed through the filter.
It will of course be understood that the operations which have been described
as occurring in regular sequence really occur simultaneously throughout the tank,
for while certain buckets are rising, other buckets are descending, and the process
of oxidation and combination of the oxide or hydroxide with impurities in the
water goes on continuously.
The aeration of the water within the tank I accomplished by this apparatus is
much more thorough than has been accomplished by former apparatus. In such
apparatus air has usually been introduced into the tank through a pipe and bubbles
upward through the water in the tank, necessarily coming in contact with only a
small portion of the water in the tank. Much power is also required to operate the
blower used in an apparatus of this kind. In the present apparatus the air is
carried downward into the water by the buckets or the iron containing chambers
themselves, being pocketed therein, and is discharged from these buckets, as they
pass through the water, air passing through practically the whole of the body of
water within the tank. Much less power is required for introducing air in this
manner than by the blower.

page_text: The use of a large number of comparatively small buckets rather than a few
longitudinal chambers results in a more thorough distribution of the iron particles
in the tank, there being no liability of the iron to collect at one end of the tank.
The operation of the apparatus is more uniform for this reason.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. In an apparatus for purifying water, the combination, with a tank or
receptacle for the water to be purified, of receptacles adapted to contain metallic
iron in a finely divided condition, and means for alternately passing said receptacles
through the air and through the water in said tank, said receptacles being sub-
stantially air tight upon the sides which are uppermost when they enter the water
and closed on the lower sides, to prevent the escape of the iron, but having in said
lower sides perforations through which water and air may pass, whereby free
entrance of air and water is afforded but the escape of the iron is prevented and
the receptacles are caused to pocket air and carry the same downward into the
water, substantially as described.
2. In an apparatus for purifying water, the combination, with a tank or
receptacle for the water to be purified, of a shaft revolubly mounted within said
tank, and receptacles adapted to contain metallic iron in a finely divided state,
mounted upon said shaft and arranged to be carried alternately through the air
and through the water in said tank when the shaft revolves, said receptacles being
substantially air tight upon the sides which are uppermost when they enter the
water and closed on the lower sides, to prevent the escape of the iron, but having
in said lower sides perforations through which water and air may pass, whereby
free entrance of air and water is afforded but the escape of the iron is prevented
and the receptacles are caused to pocket air and carry the same downward into the
water, substantially as described.
3. In an apparatus for purifying water, the combination, with a tank or
receptacle for the water to be purified, of buckets or similar receptacles, adapted
to contain metallic iron in a finely divided state, and to permit of the free passage
of air and water in and out thereof, but to prevent the escape of iron therefrom,
and means for passing said buckets alternately through the air and through the
water in said tank, said buckets being closed at the end which is undermost when
they enter the water, to prevent the escape of the iron, but being perforated in
said end to permit the free passage of air and water, substantially as described.
4. In an apparatus for purifying water, the combination, with a tank or
receptacle for the water to be purified, of buckets or similar receptacles, adapted
to contain metallic iron in a finely divided state, and to permit of the free passage
of air and water in and out thereof, but to prevent the escape of iron therefrom,
and an endless carrier for said buckets, adapted to carry the buckets alternately
through the air and through the water in said tank, said buckets being closed at
the end which is undermost when they enter the water, to prevent the escape of
the iron, but being perforated in said end to permit the free passage of air and
water, substantially as described.
5. In an apparatus for purifying water, the combination, with a tank or
receptacle for the water to be purified, of buckets adapted to receive and hold
metallic iron in a finely divided state, and to permit of free entrance and exit of
water and air, a shaft 4 revolubly mounted within said tank, and wheels 7 mounted
thereon and having said buckets secured thereto, said buckets being closed at the
end which is undermost when they enter the water, but being perforated in said
end to permit the free passage of air and water, substantially as described.
6. In an apparatus for purifying water, the combination, with a tank or
receptacle for the water to be purified, of a shaft revolubly mounted therein,
wheels 6 mounted on said shaft, and buckets 7 secured to said wheels, and having

page_text: plates 8 perforated to permit of the passage of air and water into and out of said
buckets, but to prevent the escape of solid substances from said buckets, substantially
as described.
7. In an apparatus for purifying water, the combination, with a tank or
receptacle for the water to be purified, of a shaft revolubly mounted therein,
chambers 16 arranged about said shaft and supported thereby and arranged to be
carried alternately through the air and through the water when said shaft is
rotated, each chamber being imperforate on that side which is uppermost when it
enters the water and having perforations upon its lower side, and hoods 17 secured
to said chambers and arranged to force air into said chambers as they enter the
water, substantially as described.
Dated this 1st day of June 1896.
W. GORDON WATERMAN.