Improvements in or relating to the Filtration and Purification of Liquids, and Apparatus therefor.
Year: 1894

page_text: Date of Application, 17th Feb., 1894
Complete Specification Left, 19th Nov., 1894-Accepted, 16th Mar., 1895
PROVISIONAL SPECIFICATION.
Improvements in or relating to the Filtration and Purification of
Liquids, and Apparatus therefor.
A communication from PIERRE DE MOL and AMÉDÉE WILBAUX, Manufacturers,
103, Rue Masni, Laeken, near Brussels, Kingdom of Belgium.
I, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,
Chartered Patent Agent, do hereby declare the nature of this invention to be as
follows:-
:-
This invention consists first in a system and then an apparatus hereinafter
described giving extremely rapid, regular, and perfect filtration of fluids, and any
desired degree of purification of the latter, by the practical and industrial
application which the inventor has made of Berthollet's law of "double decom-
position," with a view to attain those ends.
System of Filtration. The system of filtration is based on the employment of
1. Sponges cleansed from grease, sterilised and rendered capable of readily
absorbing water; the object being to retain a part of the matter held in
suspension and eliminate all fatty, muddy, viscous, and oozy substances.
2. A series of five kinds of felts; viz. made of (a) goats hair; (b) hair of savage
animals; (c) rabbits' hair; (d) cows' hair; and (e) dogs' hair.
All these felts are duly and thoroughly sterilised, after having been cleansed froin
grease; and one or the other of these varieties of felt is employed according to
the situation they are to occupy in the apparatus, the nature of the liquids to be
treated, and the results to be obtained.
For example: If dogs' hair felt is used with a ferruginous water, after 24 hours
nothing more will pass through the felt has become as hard as a board, and its
surface as sharp as a razor; whereas, for the treatment of molasses, syrup or sugar-
cane juice, this species of felt is indispensable. From the bacteriological and
microbiological point of view, I utilise three varieties of felt or special cotton
fabrics, cleansed of all grease, sterilised, and rendered hydrophile i.e., having a
great affinity for water.
Purification. To utilise Berthollet's law necessarily presupposes a complete
knowledge of the soluble or insoluble saline compounds in the water to be
treated, so as to know whether, under the conditions, a change of state is
possible; and consequently it is found necessary to undertake an antecedent
analysis of the liquids, in order to determine whether the double exchange can take
place and under what conditions.
The means or agents of reaction for purposes of purification are as follows:-
1. Six kinds of wood-charcoal obtained by distillation with acids, which are
utilized after preliminary destruction of the sap and complete sterilisation, and
lastly after chemical rehabilitation. Each kind of carbon has its own special
reaction, and no one of them gives the same results as any of the others; wherefore
they cannot be used indifferently. The analysis of the water determines in each
individual case which species of wood-charcoal is most suitable and whether alone
or mixed with any other, and in what proportions the admixture is to be made.
The following are the several kinds of wood-charcoal referred to:-1) white
wood; 2) beech; 3) birch; 4) oak; 5) willow; 6) elm.
2. Three kinds of graphite, or retort coke, carefully assorted and, as regards
Nos. 2 and 3, chemically prepared in the first and second stage. By means of

page_text: these graphites the speed of reaction i.e., of the decomposition may be accelerat
or retarded.
The inventor has learnt, by practical experience, how to determine which of t
prepared graphites must be used in every case, or what admixture of two or of
of the three in order practically and industrially to purify by double decompositio
the considerable hourly volumes of water traversing the small apparatus which, f
the dimensions 0-20 metre in diameter by 0-65 metre in height give 300 litr
per hour and for the dimensions 1 metre by 1 metre by 1 metre give 20,000 litr
hourly.
CONSTRUCTION AND ARRANGEMENT OF APPARATUS.
The construction and arrangement in each case depend upon the analysis of t
liquids and the requirements of the purchaser.
Thus, a purifying filter for hospitals has its hair filters lined with special tiss
of sterilised hydrophile cotton so as to deliver a water absolutely pure, from t
bacteriological and microbiological stand-point, whereas a purifying filter for boil
feed-water has no need of such appliances.
The composition and admixture of the charcoals one with the other may 1
varied and the correlation which must exist between the quantities of graphite a
charcoal must be established in order to obtain the various reactions derived
accordance with Berthollet's law.
A base decomposes a salt,
1, if a volatile base can be evolved:
2, if an insoluble salt can be precipitated;
3, if an insoluble salt can be formed.
An acid decomposes a salt; if, respectively,
1, a gaseous or volatile acid,
2, an insoluble acid,
3, an insoluble salt
can be formed.
A salt decomposes a salt:
1, if a volatile salt can be formed;
2, if an insoluble salt can be precipitated
3, if two insoluble' salts can be precipitated.
The filtration and purification depend therefore upon the changes of state whic
are provoked in the liquid under treatment, a gaseous, acid, a volatile base or sal
either by rendering insoluble a base, a salt, or an acid, by means of a suital
combination of the wood-charcoals and graphites.
DESCRIPTION OF THE PURIFYING FILTERS.
The following is the arrangement for giving with any liquid complete purificati
with a large and rapid delivery of the various kinds of water, alcohols, phlegms
magmas, liqueurs, wines, vinegars, sugar-cane juice, molasses, etc.
In a receptacle either round, oval, or square, with an open bottom such botto
being formed of a galvanised iron grating or a wickerwork sieve supported
brackets or with a closed bottom provided with a discharge-outlet, is placed on th
grating or wickerwork conveniently supported a suitable hair-felting with
without a superimposed felting or layer of some special tissue, of sterilise
hydrophile cotton. Above this is arranged a bed of graphite No. 1, No. 2,
No. 3, or an admixture of any two or three of the said graphites, according to t
decomposition to be brought about, and the rapidity with which the process is
be effected.
Above this, is placed the intermediate grating to which the decomposition tul
is fixed. As this tube is to extend upwards to the top of the receptacle, t
necessary depth of the graphite layer must be placed above the bottom grating
obtain the required level of the tube.

page_text: Above the second grating there is placed or not (according to the results to be
obtained) a suitable sheet of sterilized bydrophile cotton, but in any case the
requisite hair-felting.
A chamber or compartment of the apparatus is filled with the required wood-
charcoal and the layer is covered with a grating to which is fixed the suction-tube.
The top of this tube also must be brought level with the top of the receptacle
and this condition indicates the necessary depth of the layer of wood-charcoal.
Above the latter grating there is placed or not a sheet of sterilised hydrophile
cotton, but nevertheless in all cases a suitable hair-felting.
Above this again a layer of sponges, cleansed from grease, sterilised, rendered
hydrophile, and insipid or neutral as to taste and suitably heaped up.
Above, finally, comes a suitably adapted hair-felting.
Such are the antecedent arrangement and construction of the apparatus, which
are based on the following reasons and principles.
The valve or cock which feeds a compensation-basin discharges the water
containing more or less matter in suspension, which is retained by one of the felt
layers. This piece of felt admits of instantaneous removal and, another in all
respects similar being promptly substituted for it, there is practically no stoppage
in the flow while the change is made and the used felt is being washed and
cleansed.
In filters for industrial use, or with mechanical aids, (such as a centrifugal pump)
a preliminary appliance is employed which for the former is placed in the
receptacle itself perpendicularly to the flow of the water, but for the latter
placed ontside of and above the recipient, and in both cases formed of a layer
of specially prepared sponges, confined between two preferably galvanised iron
gratings, which may be square, round, or bracket-shaped.
Such preliminary appliances serve to rid the water of the grosser matters in
mechanical suspension, also to delay the choking up of the filter-sheet, and to deaden
the force of the water delivered by the pump.
In this case, there are always two such preliminary appliances one to be
exchanged for cleansing purposes as the other in use becomes obstructed and
finally choked up.
In the modified arrangement of the preliminary appliance (when superimposed
outside the receptacle) it may be mounted on brackets, which, as already stated,
may be square, round, or indeed of any shape.
Thus by means of these arrangements, a monthly cleansing suffices to keep the
apparatus in working order, and in the desired conditions of reaction; and, in fact,
a purifying filter for industrial purposes treating 20,000 litres hourly may be taken
apart, cleansed, and remounted in about an hour and a quarter.
The sponges with which say the top compartment or chamber is filled, are
intended for the function of retaining all the fatty, slimy, viscous and oozy
matters contained in the water which may pass through the sheet of felting and
the sponges so as to deliver the water under the best conditions of relative purity
to the action of the charcoal.
The suction pipe of the grating passes through the sheets of felting by means of
thoroughly tight joints.
The bacilli and microbes which rush to the suction tube on the passage of the
liquid through the charcoal are annihilated.
The charcoals are so compounded as to obtain, in concert with the graphites the
purification of the liquid by double decomposition.
The lower felt layer serves to retain all substances which through decomposition
and precipitation, have been brought by the action of the charcoals, into a state
enabling them to be retained and if it is desired to obtain a pure water, from the
bacteriological point of view, the last named layer is supplemented with a special
sheet of cotton fabric, placed beneath it, and duly cleansed from grease sterilised,
and made hydrophile i.e. to have a great affinity for water.
The grating on which these sheets lie is fitted as previously stated, with the

page_text: outlet tube passing through properly tight joints in the upper felt sheets and
serving for the escape of the gases evolved during the process of double
decomposition.
Whereas the charcoals act on the acids, the graphites act upon the charcoals
and gases.
The lowest felt sheet serves to retain all matters rendered insoluble by the
reactions during the passage of the water through the graphites and here also the
layer of felt is supplemented by a second layer beneath it, consisting of a special
sheet of cotton fabric, throughly cleansed from grease sterilised and rendered
hydrophile, to arrest anything which may have escaped the similar safeguard at the
lower felt layer.
The bottom grating carries the entire series of filtering and purifying elements,
and the water flows away by the outlet compensation basin and escapes through a
valve or cock together with the volume supplied through the inlet valve or cock
and almost instantaneously, supposing that, in the choice of an apparatus, care
has been taken to select one of a size giving the same hourly discharge and yield
as supplied by the inlet valve.
A river-filter (for waterworks or drainage purposes) or one of large size with
mechanical aids (such as a pump etc.) is preferably arranged horizontally.
The water thus filters perpendicularly downwards by its own weight and is
delivered pure at the tap or point of distribution.
as to be
For the service of the Army, and for use in the Colonies an apparatus is
employed say, of the dimensions 0.70 metre by 1·11 metre by 0-70 metre with an
hourly capacity of 15,000 litres mounted on a wheeled carriage, so
portable and provide it with American pumps, in duplicate, each of the hourly
capacity of 7,500 litres, and fixed to the side of the apparatus into which they
deliver the water; and a certain and regular supply of 15,000 litres of potable
water per hour is thereby almost instantaneously obtained.
For filters for industrial use, there is superimposed a preliminary appliance,
round, oval or square shaped, consisting of two correspondingly-shaped baskets
formed of wire or trellis work, and fitting one inside the other, with a space
between the two, large enough to contain a layer of sponges, on the bottom as
well as all round the inner cage, which is thus firmly held within the outer cage
by the pressure of the filling-in.
In this manner the object is attained of deadening the flow of water from the
pump and ridding the water to be filtered and purified of all the grosser matter
therein contained.
Dated this 16th day of February 1894.
W. P. THOMPSON & BOULT,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in or relating to the Filtration and Purification of
Liquids, and Apparatus therefor.
A communication from PIERRE DE MOL and A MÉDÉE WILBAUX, Manufacturers,
103, Rue Masni, Laeken, near Brussels, Kingdom of Belgium.
I, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,
Chartered Patent Agent, 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 :-
This invention consists firstly of a system and secondly an apparatus hereinafter

page_text: to be described, giving extremely rapid, regular and perfect filtration of fluids, and
any desired degree of purification of the latter, by the practical application which
the inventors have made of Berthoilet's law of "double decomposition," with a
view to attain these ends.
System of Filtration.-The system of filtration is based on the employment of
1. Sponges cleansed from grease, sterilised and rendered capable of readily
absorbing water, the object being to retain a part of the matter held in
suspension and eliminate all fatty, muddy, viscous and oozy substances;
2. A series of five kinds of felts; viz. made of a) goats hair; b) hair of wild
animals; c) rabbit's hair; d) cow's hair; and e) dog's hair.
All these felts are duly and thoroughly sterilised after having been cleansed
from grease; and one or the other of these varieties of felt is employed according
to the situation they are to occupy in the apparatus, the nature of the liquids to be
treated, and the results to be obtained.
For example, if dog's hair felt is used with a ferruginous water, after 24 hours
nothing more will pass through; the felt has become hard whereas for the treatment
of molasses, syrup or sugar-cane juice, this species of felt is indispensable. From
the bacteriological and microbiological point of view, three varieties of felt or
special cotton fabrics are utilised, cleansed of all grease, sterilised, and rendered
hydrophile, i.e. having a great affinity for water.
Purification. To utilise Berthollet's law necessarily presupposes a complete
knowledge of the soluble or insoluble gaseous saline compounds in the water to be
treated, so as to know whether, under the conditions, a change of state is possible;
and consequently it is found necessary to undertake a preliminary analysis of the
liquids, in order to determine whether the double exchange can take place and
under what conditions.
The means or agents of reaction for purposes of purification are as follows;-
1. Six kinds of wood charcoal, obtained by distillation with acids, which are
utilised after preliminary destruction of the sap and complete sterilisation, and
lastly after chemical restoration. Each kind of carbon has its own special reaction,
and no one of them gives the same results as any of the others; wherefore they
cannot be used indifferently. The analysis of the water determines in each
individual case which species of wood charcoal is most suitable, and whether alone
or mixed with any other, and in what proportions the admixture is to be made.
The following are the several kinds of wood charcoal referred to ;-1) white wood;
2) beech; 3) birch; 4) oak; 5) willow; 6) elm.
2. Three kinds of graphite or retort coke, carefully assorted and, as regards
Nos. 2 and 3, chemically prepared in the first and second stage. By means of
these graphites the speed of reaction, i.e. of the decomposition may be accelerated
or retarded. The following are the three kinds of graphite referred to-1.) Black
graphite, exactly as taken from the gas retort. 2.) Grey graphite, obtained by
extracting the tar from black graphite. 3.) White graphite, obtained by the
calcination of grey graphite.
The inventors have learnt, by practical experience, how to determine which of
the prepared graphites must be used, in every case, or what admixture of two or
of all of the three in order practically and industrially to purify by double
decomposition, the considerable hourly volumes of water traversing the small
apparatus which, for the dimensions 0.20 metre in diameter by 0.65 metre in height,
give 300 litres per hour; and for the dimensions 1 metre × 1 metre × 1 metre
give 20,000 litres hourly.

page_text: bacteriological and microbiological standpoint; whereas a purifying filter for boiler
feed-water has no need of such appliances.
The composition and admixture of the charcoals, one with the other, may be
varied, and the correlation which must exist between the quantities of graphite
and charcoal must be established in order to obtain the various reactions derived in
accordance with Berthollet's law.

page_text: The valve or cock A which feeds a basin B discharges the water containing
more or less matter in suspension, which is retained by the felt layer C. This
piece of felt admits of instantaneous removal, and another in all respects similar
being promply substituted for it, there is practically no stoppage in the flow while
the change is made and the used felt is being washed and cleansed.
In filters for industrial use, or with mechanical aids (such as a centrifugal pump)
a preliminary appliance R is employed, which for the former is placed in the
receptacle itselt perpendicularly to the flow of the water, but for the latter placed
outside of and above the receptacle, and in both cases formed of a layer of specially
prepared sponges, confined between two preferably galvanised iron gratings r
which may be square, round or basket-shaped.
Such preliminary appliances serve to rid the water of the grosser matters in
mechanical suspension, also to delay the choking up of the filter-sheet C, and to
deaden the force of the water delivered by the pump (see Figures 1 and 2).
In this case, there are always two such preliminary appliances, one to be
exchanged for cleansing purposes as the other in use becomes obstructed and finally
choked up.
Figures 3, 4, 5 and 6 show a modified arrangement of the preliminary appliance R
(when superimposed, outside the receptacle) it may be mounted on brackets, which,
as already stated, may be square, round, or indeed of any shape.
Thus, by means of these arrangements, a monthly cleansing suffices to keep the
apparatus in working order, and in the desired conditions of reaction; and in fact
a purifying filter for industrial purposes treating 20,000 litres hourly may be taken
apart, cleansed and remounted in about an hour and a quarter.
The sponges with which say the top compartment or chamber D is filled, are
intended for the function of retaining all the fatty, slimy, viscous and oozy
matters contained in the water which may pass through the sheet of felting C and
the sponges D, so as to deliver the water uuder the best conditions of relative
purity to the action of the charcoal.
The suction pipe of the grating F passes through the sheets of felting E and C
by means of thoroughly tight joints.
It is said that the bacilli and microbes rush to the suction tube f on the passage
of the liquid through the charcoal G, and are annihilated.
The charcoals in G are so compounded in concert with the graphites in K, as
to obtain the purification of the liquid.
The lower felt layer H serves to retain all substances which through decomposition
and precipitation, have been brought by the action of the charcoals into a state
enabling them to be retained; and if it is desired to obtain a pure water, from the
bacteriological point of view, the last-named layer H is supplemented with a special
sheet of cotton fabric placed beneath it, and duly cleansed from grease sterilised
and made hydrophile i.e. to have a great affinity for water.
The grating on which these sheets lie, is fitted, as previously stated, with the
evolution discharge tube i passing through properly tight joints in the upper felt
sheets E, C and A, and serving for the escape of the gases evolved during the
process of double decomposition.
Whereas the charcoals in G act on the acids, the graphites K act upon the
charcoals and gases.
The felt sheet L serves to retain all matters rendered insoluble by the reactions
during the passage of the water through K, and here also the layer of felt is
supplemented by a second layer beneath it, consisting of a special sheet of cotton
fabric; thoroughly cleansed from grease, sterilised and rendered hydrophile, to
arrest anything which may have escaped the similar safeguard at H.
The bottom grating, supported at m m m m carries the entire series of filtering
and purifying elements and the water flows away by the outlet into the basin O,
and escapes through a valve or cock P, together with the volume supplied through
the inlet valve or cock A and almost instantaneously, supposing that in the choice

page_text: of an apparatus, care has been taken to select one of a size giving the same hourly
discharge and yield as supplied by A.
A river filter (for waterworks or drainage purposes) or one of large size with
mechanical aids (such as a pump etc.) is preferably arranged horizontally as shown
in Figs. 1 and 2 of the accompanying drawings.
'The water thus filters perpendicularly downwards by its own weight and is
delivered pure at the tap or point of distribution.
For the service of the army, and for use in the colonies an apparatus is employed
say of the dimensions 0.70 metre × 111 metre × 0.70 metre with an hourly
capacity of 15,000 litres mounted on a wheeled carriage so as to be portable, and
provided with American pumps, in duplicate, each of the hourly capacity of
7,500 litres, and fixed to the side of the apparatus into which they deliver the
water; and a certain and regular supply of 15,000 litres of potable water per hour
is thereby almost instantaneously obtained.
For filters for industrial use there is superimposed a preliminary appliance,
round oval or square-shaped, consisting of two correspondingly-shaped baskets
formed of wire or trellis work and fitting one inside of the other, with a space
between the two large enough to contain (as shown in Figures 3 and 4) a layer of
sponges at the bottom as well as all round the inner cage, which is thus firmly held
within the outer cage by the pressure of the filling-in. In this manner the object
is attained of deadening the flow of water from the pump and ridding the water
to be filtered and purified of all the grosser matter therein contained, (see
Figs. 3 and 4).
Having now particularly described and ascertained the nature of the said inven-
tion as communicated to me by my foreign correspondents, and in what manner the
same is to be performed I declare that what I claim is ;-
1. The combination and arrangement of parts constituting the apparatus for
obtaining rapid continuous and regular filtration of liquids substantially as described
and illustrated in the accompanying drawings.
2. The use of hair-filters of various kinds according to the nature of the liquids
to be treated for their purification from all insoluble matters or matters in
suspension therein contained and the combination of felted sheets and specially
prepared cotton tissues to purify the liquids in respect of matters to be regarded
from the bacteriological and microbiological point of view.
3. The employment of unequal pipes of suction and of discharge indispensable
for the regular progress of the process of purification and for the regular and
constant operation of the apparatus the said pipes being affixed to the gratings
and thus independent of the interior of the apparatus or adjustably fixed on the
outside of the recipient of the purifying filter.
4. The use of different kinds of wood charcoal as specified obtained by the
distillation of acids and also of three numbers or classes of graphite effecting by
means of the combinations of the charcoals with each other and of the graphites
with each other respectively and by the correlation established between the two
admixtures charcoals and carbons based on the results of the analysis of the
liquids to be purified a change of condition in the latter by double decomposition
in accordance with Berthollet's law.
Dated this 19th day of November 1894
W. P. THOMPSON & BOULT,
Agents for the Applicant.