IMPROVEMENTS IN THE MODE OF AND APPARATUS FOR SOFTENING AND PURI- FYING WATER
Year: 1873

page_text: LETTERS PATENT to Frederick Arthur Paget, of 1, Seymour Chambers,
York Buildings, Adelphi, London, Engineer, for the Invention of
"IMPROVEMENTS IN THE MODE OF AND APPARATUS FOR SOFTENING AND PURI-
FYING WATER."-A communication from abroad by Jean Alexandre
Bérenger, of Vienna, Austria, Engineering Inspector of the Austrian
Southern Railway.
Sealed the 29th May 1874, and dated the 2nd December 1873.
PROVISIONAL SPECIFICATION left by the said Frederick Arthur Paget
at the Office of the Commissioners of Patents, with his Petition,
on the 2nd December 1873.
I, FREDERICK ARTHUR PAGET, of 1, Seymour Chambers, York Build-
ings, Adelphi, London, Engineer, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN THE MODE OF AND APPARATUS FOR
SOFTENING AND PURIFYING WATER," a communication to me from abroad by
Jean Alexandre Bérenger, of Vienna, Austria, Engineering Inspector of
the Austrian Southern Railway, to be as follows:-

page_text: boilers, and boilers generally; for washing establishments, for bleaching,
dyeing, and soap works, and other similar purposes. They consist in a
mode of and apparatus for precipitating the impurities originally
dissolved in the supply of water by means of one or more known
chemical reagents in a liquid state, preferably at ordinary temperatures.
The impurities previously chemically combined with the water being
thus brought by chemical means into a state of mechanical suspension
in the water are immediately separated therefrom by passing the mixture
through filters, preferably of the construction about to be described.
By these means the costly and cumbersome reservoirs required for what
is generally known as Clarke's process are replaced by a self-acting and
inexpensive apparatus.
Any known chemical reagent may be employed, such as lime water or
liquid carbonate of soda, to precipitate the carbonate of lime and
sulphate of magnesia. Chloride of barium can be used to precipitate
the sulphate of lime or any other reagents producing known results.
Two or more such liquid chemical reagents may be simultaneously or
successively applied to the supply of water to be filtered.
By preference water previously prepared by the process is in the course
of the working applied for forming the solution or solutions of the
reagent or reagents.
The quantity or quantities of the liquid chemical reagent or reagents
can be varied as required by means of an adjustable apparatus, such as
a force pump or a column of water, regulated by a cock or valve or by
any other known means.
The liquid reagent is injected into the main supply pipe, and gets
thoroughly mixed with it inside a vessel, which I term the mixer, con-
sisting of a cylindrical vessel, into the centre of which dips the supply
pipe within a short distance of its bottom.
When carbonate of soda is employed to precipitate sulphate of lime ag
small jet of steam is conducted into the portion of the tube where the
first mixture of the two liquids is effected. The liquid mixture is then
led from the mixer or mixers into the filters, the number of which is
regulated according to the quantity of water to be prepared.
Each filter consists of a cylindrical or conical vessel with a removable 3
cover, through which the water is supplied. The filter is fitted at its

page_text: bottom part with two horizontal gratings, between which is placed a
layer of wood shavings, and above which is a wooden hoop tightened
against the inner surface by means of a wedge of wood.
The materials with which my filters are filled consist of wood shavings
mixed with small coke or clinkers or pebbles. The proportion of coke
can be varied from one-half down to one-fifth of that of the shavings,
according the pressure of the water passing through the filter. With
this material thoroughly mixed together the filter is filled, the different
layers being successively stamped down.
Each filter is fitted with two gauge cocks, one at the top and the
second at the bottom part.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Frederick Arthur Paget in the Great Seal Patent
Office on the 2nd June 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, FREDERICK
ARTHUR PAGET, of 1, Seymour Chambers, York Buildings, Adelphi,
London, Engineer, send greeting.
L
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Second day of December, in the year of
our Lord One thousand eight hundred and seventy-three, in the thirty-
seventh year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Frederick Arthur Paget, Her special
licence that I, the said Frederick Arthur Paget, my executors, admi-
nistrators, and assigns, or such others as I, the said Frederick Arthur
Paget, my executors, administrators, and assigns, should at any time agree.
with, and no others, from time to time and at all times thereafter during.
the term therein expressed, should and lawfully might make, use, excrcise,
and vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS
IN THE MODE OF AND APPARATUS FOR SOFTENING AND PURIFYING WATER," (com-
municated to me from abroad by Jean Alexandre Bérenger, of Vienna,
Austria, Engineering Inspector of the Austrian Southern Railway) upon
the condition (amongst others) that I, the said Frederick Arthur Paget,
my executors or administrators, by an instrument in writing under my, or
.
1

page_text: their, or one of their hands and seals, should particularly describe and
ascertain the nature of the said Invention, and in what manner the
same was to be performed, and cause the same to be filed in the Great
Seal Patent Office within six calendar months next and immediately
after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Frederick Arthur Paget, do hereby
declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement thereof, reference being had to the Drawings
hereunto annexed, that is to say :-
These improvements relate to a self-acting process for softening water
for use in towns, at railway pumping stations, for locomotive steam
boilers, and boilers generally; for washing establishments, for bleaching,
dyeing, and soap works, and other similar purposes. They consist in a
mode of and apparatus for precipitating the impurities originally
dissolved in the supply of water by means of one or more known
chemical reagents in a liquid state, preferably at ordinary temperatures.
The impurities previously chemically combined with the water being
thus brought by chemical means into a state of mechanical suspension
in the water are immediately separated therefrom by passing the mixture
through filters, preferably of the construction about to be described.
By these means the costly and cumbersome reservoirs required for what
is generally known as Clarke's process are replaced by a self-acting and
inexpensive apparatus.
Any known chemical reagents producing known results may be
employed. Two or more such liquid chemical reagents may be simul-
taneously or successively applied to the supply of water to be filtered.
By preference water previously prepared by the process is in the
course of the working applied for forming the solution or solutions of
the reagent or reagents.
The quantity or quantities of the liquid chemical reagent or reagents
can be varied as required by means of an adjustable apparatus, preferably
in combination with an air vessel, such as a force pump or a column of
water regulated by a cock or valve or by any other known means.
The liquid reagent is injected into the main supply pipe, and gets
thoroughly mixed with it inside a vessel, which I term the "mixer,"

page_text: consisting of a cylindrical vessel, into the centre of which dips the
supply pipe within a short distance of its bottom.
When carbonate of soda is employed to precipitate sulphate of lime a
small jet of steam may be conducted into the portion of the tube where
the mixture of the two liquids is effected. The liquid mixture is then
led into the filters, the number of which is regulated according to the
quantity of water to be prepared.
Each filter consists of a cylindrical or conical vessel with a removeable
cover, through which the water is supplied. The filter is fitted at its
bottom part with two horizontal gratings, between which is placed a
layer of wood shavings, and above which is a wooden hoop tightened
against the inner surface by means of a wedge of wood.
The materials with which my filters are filled consist of wood shavings
mixed with small coke or clinkers or pebbles. The proportion of coke
can be varied from one-half down to one-fifth of that of the shavings,
according to the pressure of the water passing through the filter. With
this material thoroughly mixed together the filter is filled, the different
layers being successively stamped down.
Each of these pressure filters is fitted with two gauge cocks, one at
the top and the second at the bottom part.
I will now proceed to describe more fully the chemical processes I
prefer to apply for precipitating the impurities commonly found in
water :-
The salts usually present in water are- -Bicarbonate of lime (Ca O,
2 CO₂); bicarbonate of magnesia (Mg O, 2 C O₂) and gypsum or
sulphate of lime (Ca O, S O₁); sulphate of magnesia (Mg O, SO;;
chloride of magnesium (Mg Cl); and chloride of calcium (Ca CI). The
first three named salts which are the most commonly found are particu-
larly injurious in water used in steam boilers, as they form insoluble
deposits. The last three are less common, and while not so injurious
for steam producing purposes, yet it is extremely economical to separate
them from water used in washing establishments, in soap works, and
also in bleaching and dye works, and in similar establishments.
I will suppose that a given water to be purified contains all these
different salts. I should then proceed as follows:-I introduce into the
mixer, together with the water to be purified, a mixture of lime water

page_text: .
and of caustic alkali in quantities determined by the chemical compo-
sition of the water. The bicarbonate of lime is thereby precipitated.
Should the said water also contain silicic acid, or should it be condensed
water holding oily substances due to the lubricants or otherwise, these
are also partly separated at the same time. The salts of magnesia are
precipitated by means of the caustic alkali, and the rest of the fatty
substances are saponified. By these means an alkaline carbonato is
formed by the combination of one part of the bicarbonate of magnesia
with the caustic alkali, and thereby only one part of the caustic alkali is
transposed. If the contents of sulphate of lime are considerable then.
the remainder of the alkaline carbonate formed will not be present in
sufficient quantity to precipitate the surplus of the sulphate. In such
a case the process of purification has to be continued. The partly
purified water, the already formed precipitate, together with an addi-
tional supply of alkaline carbonate, are conducted into a second mixer
of a capacity greater than the first, by which the surplus sulphate of
lime and any chloride of calcium or chloride of aluminium present are
precipitated in their turn.
In order to accelerate the chemical reaction between the sulphate of
lime and the alkaline carbonate I prefer to conduct a jet of steam into
the current of the alkaline solution. The water thus prepared is then
ready to be conducted into the pressure filter or filters.
Having now set forth the nature of the more specially chemical
portion of my Invention, I will proceed to describe more fully the
arrangements of apparatus that I employ for preparing the reagents,
mixing the same with the water to be purified, separating the precipitate
or precipitates, etc.
One of my two Sheets of Drawings shews the apparatus in its entirety,
the other the details of the form of filter that I employ and also of my
so-called mixer. In both Sheets the same letters refer to the same
parts.
In Figs. Ia and Ib, which are respectively a side elevation and a plan,
A is a tub or tank or reservoir, within which the lime water is prepared;
B is a similar tub or tank for making the liquid caustic alkali; C is a
similar but larger tank for receiving the mixture of lime water and of
the caustic alcali; A¹ is a tub for the solution of the alcaline carbonate;
C', a larger receptacle for the alcaline hydro-carbonate. The liquid used

page_text: 2
Both the filters and the mixers are fitted with gauge or trial cocks
y, y', at top and bottom in order to test at any time the regular working
of each apparatus. The mixers and the collecting pipe K are also
supplied with mud or blow-out cocks Q in order to be enabled to clear
them out at any time of any sediment; and S, S, S, S, indicate pressure
gauges fitted on the two air vessels and the two mixers.
The general arrangement we have described is to be applied when
large quantities of water containing sundry different kinds of impurities
are to be treated, and it will be obvious that with purer kinds of water
and with smaller quantities simpler apparatus can be adapted. For
instance when comparatively small volumes of water have to be treated,
such as for one or two steam boilers, only a single reservoir or tank can
be employed, the same being placed in direct connection with one of my
pressure filters. This reservoir has to be set up at such a height above
the said filter that the prepared water can flow through it by gravity, a
height of about seven feet being found sufficient with my filter. Into
the reservoir the reagent or reagents required is or are supplied in
quantities and kinds determined by the nature of the water, and the
mixture flows through the filter and issues therefrom in a purified state.
In such a case, and especially with a water supply varying in quality,
it is advisable to check the process by chemical analysis of the water.
On my second Sheet of Drawings are shewn in detail and to an
enlarged scale my peculiar pressure filters and mixers. The same letters
are applicable to the two slightly differing forms of my filters and
mixers respectively. In both the cylindrical and conical filters, Figs.
III., IV., the letters a, a, denote the peculiar wooden joint I employ.
The said joint is formed of a strip of soft wood, the inside edge of which
is serrated with saw cuts, so that a hoop is formed which can easily
adjust itself against the internal surface of the filtering vessel, and it is
closed by means of a wooden wedge. Below the joint are two gratings.
c, c¹, set to a suitable distance apart, this intermediate space being filled
with wood shavings. The capacity above the upper grating is filled up
with wood shavings mixed with small coke or clinkers or pebbles, the
proportion of coke to shavings being from one-fifth to one-half of that
of the shavings, and increasing with the pressure on the water passing
through. The filter is therewith filled in layers which are successively
stamped down. The bottom grating c¹ is carried on annular carriers of

page_text: angle iron d, ď¹ª, đª, đ™, in such wise as to leave a shallow empty space
at the bottom of the filter.
The enlarged views, Figs. V. and VI., of the two mixers indicate the
slight variation necessary according as the water supply is led in from
› above or from below, f being the supply and the outlet pipe in cach
case. The two mixers successively used in my complete form of
apparatus only differ as to size.
9
Having now fully set forth the nature and modes of carrying out my
Invention, I declare that I claim subjecting water to processes for the
expulsion of its impurities, substantially as and for the purposes
described.
In witness whereof, I, the said Frederick Arthur Paget, have here-
unto set my hand and seal, this First day of June, in the year
of our Lord One thousand eight hundred and seventy-four.