Improvements in Apparatus for Purifying and Sterilising Drinkable Waters.
Year: 1899

page_text: Date of Application, 22nd Aug., 1899
Complete Specification Left, 23rd Apr., 1900-Accepted, 4th Aug., 1900
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Purifying and Sterilising Drinkable
Waters.
I, HENRI PAUL AUGUSTE GAILLET, Managing Director of the Société Anonyme
des Ateliers de Construction de la Madeleine, of S, Rue Nicolas Leblanc, Lille,
in the French Republic, do hereby declare the nature of this invention to be as
follows:-
This invention relates to improvements connected with the purification of
drinkable waters, and which improvements at the same time ensure and main-
tain the sterilisation of the said waters. They are carried out by means of a
combination of apparatus which will now be described.
Certain of the apparatus forming parts of the whole combination are already
known and used as purifiers properly so-called, for industrial purposes, but the
present invention relates to their combination and certain constructional and
working peculiarities which transform them into efficient sterilizers and render
them suited to forming a combined apparatus capable of being practically
applied to water-distributers, or important reservoirs.
Experience has shewn that numerous methods, physical and chemical, can be
used to sterilise water. Now personal investigations have led me to conclude
that, in a general manner, a single method should not rigidly be adhered to,
that is to say, it is necessary to provide for purification and sterilisation of
waters by different chemical means suited to the varying nature and com-
position of the waters to be treated.
This point is insisted upon, for I do not mean to say only that the doses of
the reagents will vary with the composition of the waters to be treated, as is
the case for the treatment of water for industrial purposes, but even that the
reagents themselves may be of various kinds, i.e., of different natures according
to the composition of the liquids to be treated and the result to be attained.
By reason of this consideration, the whole of this purifying and sterilising
apparatus may be modified in certain of its parts; but in any case, and whatever
be the modifications in the erection or construction thereof, in the sizes and
dimensions necessitated by circumstances, the essential features which characterise
this invention, having for its object the complete and continuous treatment of
drinkable waters, are:-
(1). Circulation of the water to be treated and of the reagents in completely
closed apparatus, avoiding the slightest contamination by direct atmospherical
contact.
(2). Air-tight and water-tight closing of the different apparatus and parts
by hydraulic joints or seals which allow easy inspection.
(3). Use of air-filters with a siphon tube to ensure communication of the
apparatus with the atmosphere and allowing the regular working thereof, with-
out risk of contamination.
(4). Reagent-distributers dispensing with the necessity of raising the products

page_text: to the upper portion of the installations, in such a manner as to reduce hand-
work, to simplify maintenance, and especially to avoid all contamination.
(5). Separation of the purifying apparatus properly called from the clarifiers
(decanters or filters), in such a manner as to permit a correction chemically of
the composition of sterilised waters, in case this is advantageous, for instance,
in case of compulsory use from an excess of reagent or in the case of chemical
sterilising action modifying the nature of the water to too great an extent.
(6). The use of special apparatus intended automatically to effect the cor-
rections in question, without endangering the sterilisation.
(7). Use, on occasion, of the residues of chemical purification for the re-forma-
tion of the calcareous elements in waters chemically purified and sterilised.
(8). Occasional addition of security-filters allowing clarification to be com-
picted by simple decantation, whilst avoiding chance contamination of the
filtering substances, which should receive only sterilised liquids.
In principle the treatment should comprise two portions:-
("). A chemical and bacteriological examination which allows the nature and
the doses of the reagent or reagents employed, to be determined.
(b). The selection of the apparatus to be used.
Of the scientific portion of the treatment, I shall not treat, since it is variable
infinitely and cannot form the subject of any special claim; the material com-
bination worked in such manner as to permit the application of multiple for-
mulas and reagents is, on the contrary, the subject of this patent.
The water to be treated is conducted through a pipe fitted with a distributer
cock, which is fitted with regulating devices and which may be of any well
known type.
A water-wheel of any suitable pattern, is rotated by the incoming water from
this cock. The said water-wheel is superposed upon, but separated from a
distributing trough or tank, contrary to what is usually done in the case of
industrial water purifying, in such manner that the water before reaching this
tank may be previously sent through certain apparatus for the purpose of being
subjected to a preliminary treatment by the addition of a suitable reagent.
The following is an appropriate receiver suited to effect this treatment more
particularly when a reagent soluble in water to only a limited extent is used,
as is the case for metallic iron for instance; such receiver is mounted on au
axis and may be rotated by means of suitable mechanism, which will allow it to
see-saw to reverse the circulation of the liquid and renew the contact surfaces.
The inlet and outlet water-pipes form the pivots or axle-ends and within the
receiver they deliver to towards opposite ends of the receiver; meshes or sieves
are also placed in the receiver. When this treatment is of no particular advant-
age, a direct connection between the pipes leading from and to the tank from
the receiver, may be opened, thus avoiding passage through the receiver; or
the latter might even itself be dispensed with. This arrangement is of import-
ance since the addition of a reagent for preparatory or preliminary treatment
may be useful for certain periods, without, however, becoming continuous.
Directly or indirectly, as stated above, the water passes from the water-wheel
into the distributing tank, which latter is closed and furnished with an air-tight
or hydraulic lid preventing all communication with the outer air; it is also
provided with an air siphon-filter and ordinary regulating and distributing
devices. For the hydraulic seals of the various apparatus I recommend, pre-
ferably, the use of lime-water which prevents pollution and destroys germs.
This air siphon-filter is for the purpose of dispensing with various apparatus
communicating direct with the atmosphere, whilst allowing, by indirect relation,
circulation of the liquids according to the laws of hydrostatics. For this pur-
pose the entrance and the ultimate outlet of the air take place across a small
filtering layer, consisting of cotton-wool or other porous substance, retarding the
passage of corpuscles or micro-organisms suspended in the air. The air filter

page_text: properly spreaking is formed of a small movable cylindrical basket, self-adjusting
with slight friction in a socket terminating in a kind of siphon which when so
required, allows any liquid accidentally drawn over, to escape freely, always with-
out setting up direct communication between the apparatus and the atmosphere.
Originally I foresaw that the flow of water to be treated should be divided into
two parts, but a greater or less division may take place, or division may even be
avoided, according to the nature of the treatment to be followed.
Hypothetically and in fact almost generally, lime is used.
A second receiver similar to the first one, serves to introduce this reagent,
protected from the air and exterior emanations, into a saturator. A direct con-
nection between the pipes of the second receiver, allows the working of the latter
to be suspended, for cleaning, charging or other purposes.
The saturator is of any ordinary type furnished or not, as may be found
necessary, with a mixer or stirrer, but it is closed by an air-tight lid, by means
of an hydraulic seal, and has an air-filter. The apparatus is thus preserved
from all impurities and sheltered from external contamination. The bearing
of the shaft axis is furnished with an hydraulic joint-cover preventing all com-
munication with the outside air, but without causing frictional resistance to its
rotation, as would be the case if ordinary stuffing-boxes were used. This arrange-
ment of joint-cover is of any ordinary pattern.
Adjoining the saturators is a purifier in which the water to be treated. is
mixed with the reagent, in proportions determined by chemical and bacterio-
logical investigation of the particular water. This purifier may be of any
ordinary type whatever. It should be air tight, hydraulically sealed, and pro-
vided with an air-filter, thus preventing contamination from the outside. The
use of internal decantation surfaces is not absolutely indispensable and if these
are not used, an increase of the volume of this receptacle will be furnished.
The mixture of the water and of the one or more reagents is effected in a tank
fitted with an elbowed pipe and connected to a central purifying plunger pipe,
and arranged under the man-hole or inspection-inlet.
If the method employed for purifying and sterilising water has not resulted in
an alteration of the chemical composition to such a degree that an after cor-
rection will be necessary or advantageous, the treatment may be stopped in the
purifier which should be of sufficient size to permit clarifying by decantation,
and may, besides, be completed by a filter working according to the conditions
set forth in (8).
On the other hand, if sterilisation has affected the water to any great extent,
for instance, referring only to the case of lime, if the operator has been obliged
to make use of a dose lowering to too great an extent the hydrotimetrical degree
of the drinkable water or even of an excess of reagent imparting to the said
water an alkaline reaction, the treatment is completed by the total or partial
restitution of the eliminated calcareous elements.
In the case of lime, the most usual for the applications intended, it is necessary
to consider that if the dose employed has lowered the hydrometrical degree to a
minimum whilst leaving a purified water wholly neutral, lime carbonate can
only be restored, in order to raise the degree, either by a direct addition of
this reagent, or in a more practical manner, by the formation within the liquid
itself of the bicarbonate in question by means of the addition of lime and car-
bonic acid in suitable proportions.
The addition of lime will be easily effected by regulating the delivery of the
saturator.
The addition of carbonic acid may be obtained by several methods. If the
purifying installation is sufficiently important to justify the manufacture on
the spot, of lime by means of lime-kilns, the gases from the kiln, suitably purified
and washed, may be used as takes place in the sugar-industry for defecation. If
the importance of the installation is, on the other hand, too small to include
any complication, compressed and liquified commercial carbonic acid may be

page_text: used, or better still, recourse may be had to arrangements analogous to those
which serve for the manufacture of seltzer-water (soda-water) as far as con-
cerns the production and washing of the carbonic acid gas.
For ordinary installations, I prefer to manufacture carbonic acid by using
the residues of decantation which are formed of nearly pure lime carbonate, and
in a moist state which simplifies the operation. The gaseous carbonic acid is
then prepared in a receiver into which the sediment of the purifier and of the
clarifiers can be diverted by suitable conduits; prepared solution of acid of a
proper strength contained in an upper reservoir is then delivered into this
receiver by suitable connections. Preferably the distributers (valves cocks, etc.)
are similar to those used for distributing the soluble reagents for industrial
water purifiers.
The evolved gas, previously purified in a washer, is conveyed into a carbonator.
The washer consists of a series of caps or domes which cause the gas to bubble
through a series of annular cups or vessels containing water; the washing is
very thorough and the gas may be under slight pressure and to facilitate the
diffusion of the gas within the liquid, the angles or edges of the cups are ridged
or toothed.
The washing of the gas in this apparatus is effected by a stream of ordinary
water and the outlet takes place through either a siphon, or a tank device with
a pipe dipping into the same, so as to avoid in the first place any obstruction
within the apparatus and in the second place any loss of carbonic acid gas.
The carbonator may be of various forms. Preferably I use an arrangement
which allows the evolution of gas at a very low pressuré, 25 to 50 millimetres
of water, for example, so as not to counteract the evolution in the generator, of
carbonic acid gas and the automatic regulation of the distribution of the acid
employed for the decomposition of the sediment of lime carbonate. (It is to be
understood that this lime carbonate, the residue from purification, may be
replaced by any other suitable material, and also that the acid used for the
decomposition thereof, may be any one suitable. These might be hydrochloric
acid, sulphuric acid, etc.; and industrial acid residues such as the bi-, tri-, or
per-sulphates of soda which certain industries leave as residues and which may be
purchased very cheaply, thus reducing the cost of my method of treatment.
A suitable carbonator is composed of a receiver in the shape of a trough having
a semi-cylindrical bottom inclined from the horizontal, in order the facilitate
the emptying of the lime carbonate mud which may be deposited there and
which, in case of need, may also serve for the production of carbonic acid gas.
A plain partition formed of strips or plates dipping below the surface of the
liquid will allow, in most cases, and particularly for low outputs, the gas to
pass into the midst of the water for carbonating the lime; but when the force
produced by the fall of water on the water-wheel will allow it, or when another
motive force is available, the following arrangement may be employed.
A kind of drum is mounted within the carbonating trough on a horizontal
axis and driven by a worm wheel. This drum is provided with compartments
open along its generatrices, with a toothed edge to facilitate the diffusion of the
carbonic acid gas in the liquid. These compartments are constructed in such a
manner that the compression of gas may be avoided above that which is strictly
necessary to ensure bubbling over, in order to reduce to a minimum the expendi-
ture of motive force and to complicate neither the production of gas nor the
regulation of its emission which are, of course, determined by the pressure. The
evolution will take place on an average under a pressure of 25 to 50 millimetres
of water. The carbonating apparatus is furnished with an hydraulically sealed
man-hole constructed in such a manner that the column of liquid may balance the
maximum pressure of gas during normal supply. The bearings of the shaft are
also so constructed that no leakage of gas can take place but without, however,
creating frictional resistance to the rotation of the shaft.
From the carbonator, the water which has been muddled by a certain quantity

page_text: of insoluble lime carbonate, passes into the clarifying decanter which may be
of any type desired. It should be fitted with an air-tight lid, an inspection
hole and an air-filter intended to avoid direct communication with the atmos-
phere.
The clarified, purified and sterilised water passes out by an outlet device and
is delivered into the supply-reservoirs. In case of need, it may be passed through
carbon filters, for the purpose of perfecting the decantation by retaining the
light corpuscles which have not been deposited by gravitation. This filter
would receive only sterilised water so that it avoids the criticism applicable to
filters in general, that rapid pollution may take place when these apparatus act
at the same time as both sterilisers and clarifiers.
With certain special waters whose treatment does not necessitate the use of an
appreciable excess of lime, the operation may, as stated above, finish after the
purifier properly so-called, and may then end with a passage through carbon
which not only clarifies but even retains all traces of alkalinity occasioned by
the sterilising reaction.
This combination of apparatus thus allows purification and sterilisation by
the application of various chemical formulae suited to the nature and com-
position of the waters.
Improvements in Apparatus for Purifying and Sterilising Drinkable
Waters.
I, HENRI PAUL AUGUSTE GAILLET, Managing Director of the Société Anonyme
des Ateliers de Construction de la Madeleine, of 8, Rue Nicolas Leblanc, Lille,
in the French Republic, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
This invention relates to improvements connected with the purification of
drinkable waters, and which improvements at the same time ensure and main-
tain the sterilisation of the said waters. The improvements are carried out by
means of a combination of apparatus which will now be fully described.
Certain of the apparatus forming parts of the whole combination are already
well known and used as purifiers properly so-called for industrial purposes, but
the present invention relates to their combination and certain constructional and
working peculiarities which transform them into efficient sterilizers and render
them suited to forming a combined apparatus capable of being practically
applied to water-distributers, or important reservoirs.
Experience has shewn that numerous methods, physical and chemical, can be
used to sterilise water. Now personal investigations have led me to conclude
that, in a general manner, a single method should not rigidly be adhered to,
that is to say, it is necessary to provide for purification and sterilisation of
waters by different chemical means suited to the varying nature and com-
position of the waters to be treated.
This point is insisted upon, for I do not mean to say only that the doses of

page_text: the reagents will vary with the composition of the waters to be treated, as is
the case for the treatment of water for industrial purposes, but even that the
reagents themselves may be of various kinds, i.c. of different natures according
to the composition of the liquids to be treated and the result to be attained.
By reason of this consideration, the whole of this purifying and sterilising
apparatus may be modified in certain of its parts; but in any case, and whatever
be the modifications in the erection or construction thereof, in the sizes and
dimensions necessitated by circumstances, the essential features which characterise
this invention, having for its object the complete and continuous treatment of
drinkable waters, are:-
(1). Circulation of the water to be treated and of the reagents in completely
closed apparatus, avoiding the slightest contamination by direct contact with the
atmosphere.
(2). Air-tight and water-tight closing of the different apparatus and parts
by hydraulic joints or seals which allow easy inspection.
(3). Use of air-filters with a siphon tube to ensure communication of the
apparatus with the atmosphere and allowing the regular working thereof, with-
out risk of contamination.
(4). Reagent-distributers dispensing with the necessity of raising the products
to the upper portion of the installations, in such a manner as to reduce hand-
work, to simplify maintenance, and especially to avoid all contamination.
(5). Separation of the purifying apparatus properly called from the clarifiers
(decanters or filters) in such a manner as to permit a correction chemically of
the composition of sterilised waters, in case this is advantageous, for instance.
in cases of compulsory use from an excess of reagent or in the case of a chemical
sterilising action modifying the nature of the water to too great an extent.
(6). The use of special apparatus intended automatically to effect the cor-
rections in question, without endangering the sterilisation.
(7). Use, on occasion, of the residues of chemical purification for the re-forma-
tion of the calcareous elements in waters chemically purified and sterilised.
(8). Occasional addition of security-filters allowing clarification to be com-
pleted by simple decantation, whilst avoiding chance contamination of the
filtering substances, which should receive only sterilised liquids.
Upon the accompanying drawings, Figure 1 shews diagrammatically the whole
of the combined apparatus, and affords a view of the whole operation. Figures 2, 3
and 4 shew in front elevation, side view and plan respectively, the whole of these
apparatus for commercial use. Figure 5 shews in section the apparatus for
producing carbonic acid gas. Figure 6 shews in longitudinal and cross section
the carbonating apparatus. Fig. 7 illustrates the details of the water tank
furnished with its driving wheel and an air filter.
In principle the treatment should comprise two portions:-
(a). A chemical and bacteriological examination which allows the nature and
the doses of the reagent or reagents employed, to be determined.
(b). The selection of the apparatus to be used.
Of the scientific portion of the treatment, I shall not treat, since it is variable
infinitely and cannot form the subject of any special claim in this specification;
on the other hand, the subject of this invention is the special material com-
bination worked in such a manner as to permit the application of multiple
formulas and reagents.
The water to be treated is conducted through a pipe fitted with a distributer
cock A, which is provided with regulating devices and which may be of any
well-known type.
A water-wheel B of any suitable pattern, is rotated by the incoming water
from this cock and ensures or assists the working of certain parts of the apparatus
as will be presently described. The said water-wheel is superposed upon, but
separated from a distributing trough or tank, contrary to what is usually done
in the case of industrial water-purifying, in such manner that the water before

page_text: reaching this tank may be previously sent through certain apparatus for the
purpose of being subjected to a preliminary treatment by the addition of a
Suitable reagent.
D is an appropriate receiver suited to effect this treatment more particularly
when a reagent soluble in water to only a limited extent is used, as is the case
with iron, for instance; such receiver is mounted on an axis and may be rotated
by means of suitable mechanism d: which will allow it to swing over or invert
itself to reverse the circulation of the liquid and clean the contact surfaces.
The inlet and outlet water-pipes form the pivots or axle-ends and within the
receiver they deliver at a ' towards opposite ends of the receiver; meshes or
sieves a dare also placed in the receiver D. When this treatment is of no
particular advantage, a direct connection d³ between the pipes leading from and
to the tank from the receiver may be opened, thus avoiding passage turough the
receiver D; or the latter might even itself be dispensed with.
This arrangement is of importance since the addition of a reagent for a
preparatory or preliminary treatment may be useful for certain periods, without,
however, becoming continuous.
Directly or indirectly, as stated above, the water passes from the water-wheel B
into the distributing tank C, which latter is closed and furnished with an air-
tight or hydraulic lid O preventing all communication with the outer air; it is
aiso provided with an air siphon-niter A and ordinary regulating and distribut
ing devices. For the hydraulic seals of the various apparatus I recommend
preferably, the use of lime-water which prevents pollution and destroys germs.
This air siphon-filter is 1or the purpose of dispensing with various apparatus
communicating direct with the atmosphere, whilst allowing, by indirect relation,
circulation of the liquids according to the laws of hydrostatics. For this pur-
pose the entrance and the ultimate outlet of the air take place across a sinall
nltering layer, consisting of cotton-wool, glass-cloth or other porous substance,
retarding the passage of corpuscles or micro-organisms suspended in the air.
The air filter properly speaking is formed of a small movable cylindrical basket,
self-adjusting with slight friction in a socket terminating in a kind of siphon N
which, when so required, allows any liquid accidentally drawn over, to escape
freely, always without setting up direct communication between the apparatus
and the atmosphere.
Originally it was foreseen that the flow of water to be treated should be divided
into two parts, but a greater or less division may take place, or division may
even be avoided, according to the nature of the treatment to be followed.
Hypothetically and, in fact, almost generally, lime is used.
A second receiver E similar to the first D serves to introduce this reagent,
protected from the air and exterior emanations, into a saturator F. The re-
ceiver E serves to temper the lime; the lime-milk formed therein passes to the
saturator F where clarification takes place. A direct connection between the
pipes of the receiver E allows the working of the latter to be suspended, for
cleaning, charging or other purposes.
pre-
The saturator F in which the lime water or other reagent solution
pared, is of any ordinary type furnished or not, as may be found necessary,
with a mixer or stirrer, but it is closed by an air-tight lid, by means of one
or more hydraulic seals O and has an air-filter N. The apparatus is thus pre-
served from all impurities and sheltered from external contamination. The bear-
ing of the shaft axis is furnished with an hydraulic joint-cover preventing all
communication with the outside air, but without causing frictional resistance to
its rotation, as would be the case if ordinary stuffing-boxes were used. This
arrangement of joint-cover is of any ordinary pattern.
Adjoining the saturators is a purifier G in which the water to be treated is
mixed with the reagent, in proportions determined by chemical and bacterio-
logical investigation of the particular water. This purifier G may be of any
ordinary type, and is provided with an overflow pipe leading to H. The one

page_text: I employ is as illustrated, and is air-tight, has an inlet or man-hole O hydrauli-
cally sealed, and is provided with an air-filter, thus preventing contamination
from the outside.
The use of internal decantation surfaces y as shewn on the drawings, is not
absolutely indispensable and if these are not used, an increase of the volume of
this receptacle will be furnished. The mixture of the water and of the one or
more reagents is effected in an inner bucket gi fitted with pipes and connected
to a central purifying plunger pipe g² arranged beneath the man-hole or inspec-
tion inlet.
If the method employed for purifying and sterilising water has not resulted
in an alteration of the chemical composition to such a degree that an after
correction will be necessary or advantageous, the treatment may be stopped in
the purifier G which should be of sufficient size to permit clarifying by decanta-
tion, and may, besides be completed by a filter working according to the con-
ditions set forth in (8).
On the other hand, if sterilisation has affected the water to any great extent,
for instance, referring only to the case of lime, if the operator has been obliged
to make use of a dose lowering to too great an extent the degree of hardness of
the drinkable water or even used an excess of reagent imparting to the said
water an alkaline reaction, the treatment is completed by the total or partial
restitution of the eliminated calcareous elements.
In the case of lime, the most usual for the applications intended, it is
necessary to bear in mind that if the dose employed has lowered the degree of
hardness to a minimum whilst leaving a purified water wholly neutral, lime
carbonate can only be restored, in order to raise the degree, either by a direct
addition of this reagent, or in a more practical manner, by the formation within
the liquid itself of the bicarbonate in question by means of an addition of lime
and carbonic acid in suitable proportions.
The addition of lime will be easily effected by regulating the delivery of the
saturator F.
The addition of carbonic acid may be obtained by several methods. If the
purifying installation is sufficiently important to justify the manufacture on
the spot of lime by means of a lime-kiln, the gases from the kiln, suitably
purified and washed, may be used as takes place in the sugar-industry for
defecation. If the importance of the installation is, on the other hand, too
small to allow of the inclusion of any complication, compressed and liquefied
commercial carbonic acid may be used, or better still, recourse may be had to
arrangements analogous to those which serve for the manufacture of seltzer-water
(soda-water) as far as concerns the production and washing of the carbonic acid
gas.
For ordinary installations, I prefer to manufacture carbonic acid by using the
residues of decantation which are formed of nearly pure lime carbonate in a
moist state which simplifies the operation. The gaseous carbonic acid is then
prepared in a receiver such as J into which the sediment of the purifier and of
the clarifiers can be diverted by suitable conduits ga prepared solution of
acid of a proper strength contained in an upper reservoir L is then delivered into
this receiver by suitable connections. Preferably the distributers (valves, cocks
etc.) are similar to those used for distributing the soluble reagents for industrial
water purifiers.
The evolved gas, previously purified in a washer K, is conveyed into a car-
bonator H. The washer K consists of a series of caps or domes kkk see Figure 5
which cause the gas to bubble through a series of annular cups or vessels k¹ ki
containing water; the washing is therefore very thorough and the gas may be
under slight pressure and to facilitate the diffusion of the gas within the liquid,
the angles or edges of the cups k k are ridged or toothed.
The washing of the gas in this apparatus is effected by a stream of ordinary
water and the outlet takes place through either a siphon M, or a tank device with

page_text: a pipe dipping into the same, so as to avoid in the first place any obstruction
within the apparatus and in the second place any loss of carbonic acid gas.
The carbonator H may be of various forms, see Figure 6. Preferably I use an
arrangement which allows the evolution of gas at a very low pressure, 25 to 50
millimetres of water for example, so as in no way to counteract either the
evolution in the generator of carbonic acid gas, or the automatic regulation of
the distribution of the acid employed for the decomposition of the sediment of
lime carbonate.
(It is to be understood that this lime carbonate the residue from purification,
may be replaced by any other suitable material, and also that the acid used for
the decomposition thereof, may be any one suitable. These might be hydrochloric
acid, sulphuric acid, etc.; and industrial acid-residues such as the bi-, tri-, or
per-sulphates of soda which certain industries leave as residues and which may
be purchased very cheaply, thus reducing the cost of my method of treatment).
The carbonator H is composed of a receiver in the shape of a trough having a
semi-cylindrical bottom inclined from the horizontal, in order to facilitate
the emptying of the lime carbonate mud which may be deposited there and which
in certain cases, may also serve for the production of carbonic acid gas. A
plain partition formed of strips or plates dipping below the surface of the liquid
will allow, in most instances, and particularly for low outputs, the gas to pass
into the midst of the water for carbonating the lime; but when the force pro-
duced by the fall of water on the water-wheel B will allow it, or when another
motive force is available the following arrangement, Figures and 6, may be
employed.
A kind of drum ¹ is mounted within the carbonating trough on a horizontal
axis and driven by a worm wheel gearing h². This drum is provided with com-
partments open along its generatrices, with a toothed edge to facilitate the
diffusion of the carbonic acid gas in the liquid. These compartments are con-
structed in such a manner that the compression of gas may be avoided above
that which is strictly necessary to ensure bubbling over, in order to reduce to a
minimum the expenditure of motive force and to complicate neither the pro-
duction of gas nor the regulation of its emission which are, of course, deter-
mined by the pressure. The evolution will take place on an average under
the pressure of 25 to 30 millimetres of water. The carbonating apparatus is
furnished with an hydraulically sealed man-hole or lid O constructed in such a
manner that the column of liquid may balance the maximum pressure of gas
during normal supply. The bearings of the shaft are also so constructed that
no leakage of gas can take place but without, however, creating frictional
resistance to the rotation of the shaft, as might occur with ordinary stuffing-
boxes.
The operation of the carbonater is as follows;-Water passes into the outer
receiver; the inner drum formed of partitions having toothed edges (see Figures 1
and 6) encloses successively and by reason of its rotation, within each of these
chambers, a certain volume of carbonic acid gas which is compressed and can
escape only through the teeth. The gas is therefore intimately mixed with the
water to be carbonated, its absorption being thereby facilitated. The receiver
being filled with gas at the upper portion, there is a three-fold action;-direct
contact, agitation produced by rotation of the drum, and diffusion consequent
upon the compression of the gas.
The shafting, gear-wheels and pulleys for rotating the drum are clearly
shewn in Figure 1.
From the carbonater, the water which has been rendered turbid by a certain
quantity of insoluble lime carbonate, passes into the clarifying decanter I which
may be of any type desired. It should be fitted with an air-tight lid, an
inspection hole O and an air-filter N intended, as in the previous cases, to avoid
direct communication with the atmosphere.
The clarified, purified and sterilised water passes out through an outlet

page_text: device P and is delivered into the supply-reservoirs. In case of need, it may be
passed through any ordinary carbon filters, for the purpose of perfecting the
decantation by retaining the light corpuscles which have not been deposited by
gravitation. This filter would receive only sterilised water so that it avoids the
criticism applicable to filters in general, that rapid pollution may take place
when these apparatus act at the same time as both sterilisers and clarifiers.
With certain special waters whose treatment does not necessitate the use of
an appreciable excess of lime, the operation may, as stated above, finish after
the purifier G properly so-called, and may then end with a passage through carbon
which not only clarifies but even retains all traces of alkalinity occasioned by
the sterilising reaction.
This combination of apparatus thus allows purification and sterilisation by the
application of various chemical formulae suited to the nature and composition of
the waters.
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 improvements in the purification of drinkable waters, enabling them
to undergo a complete treatment for purification, at the same time ensuring and
maintaining their sterilisation, substantially as above described and set forth.
(2). The combination apparatus for treating and rendering waters drinkable,
substantially as described and as illustrated on the accompanying drawings.
Dated this 23rd day of April, 1900. .