IMPROVEMENTS IN THE MANUFACTURE OF SULPHATE OF LIME, IN THE APPARATUS EMPLOYED THEREIN, AND IN THE ARTICLE OF MANUFACTURE PRODUCED THEREBY
Year: 1879

page_text: LETTERS PATENT to William Morgan-Brown, of the Firm of Brandon and
Morgan-Brown, Engineers and Patent Agents, of 38, Southampton Buildings,
London, and 1, Rue Laffitte, Paris, for the Invention of "IMPROVEMENTS IN
THE MANUFACTURE OF SULPHATE OF LIME, IN THE APPARATUS EMPLOYED
THEREIN, AND IN THE ARTICLE OF MANUFACTURE PRODUCED THEREBY."
communication from abroad by Zenas C. Warren, of New York, United States
of America.
A
PROVISIONAL SPECIFICATION left by the said William Morgan-Brown at
the Office of the Commissioners of Patents on the 14th November 1879.
WILLIAM MORGAN-BROWN, of the Firm of Brandon and Morgan-Brown, Engineers
and Patent Agents, of 38, Southampton Buildings, London, and 1, Rue Laffitte,
Paris. "IMPROVEMENTS IN THE MANUFACTURE OF SULPHATE OF LIME, IN THE
APPARATUS EMPLOYED THEREIN, AND IN THE ARTICLE OF MANUFACTURE
PRODUCED THEREBY." A communication from abroad by Zenas C. Warren, of
New York, United States of America.
This Invention of improvements in the manufacture of sulphate of lime relates
to the manufacture and to an improved product. Previously to this Invention
artificial sulphate of lime had been made by dissolving carbonate of lime in muriatic
acid, then precipitating it with sulphuric acid or by a soluble sulphate, and then
treating it to successive washings to remove the free acid. Unless great care was
taken in the washing, and even then traces of the acid were liable to remain, and
thus render it unsafe to use as a filling in the manufacture of paper, as a dressing
for cotton cloth and other articles which the acid would attack and damage. It
was also expensive to manufacture.
Natural sulphate of lime as calcined gypsum before it could be used as a filling
for paper had to be comminuted, which it was difficult to do properly, and then it
was liable to contain crystals, which in the manufacture of paper appeared in spots
in the latter after calendering.
Other objections existed to the use, especially as a filling for paper, of both
artificial and natural sulphate of lime prior to this Invention, the principal one of
which was that their specific gravity was greater than that of the paper pulp,

page_text: which caused them to settle when mixed in a fluid state with the paper pulp, and
thus waste in the bottoms of the vats and through the wire cloth of the paper
machine.
The object of this Invention is to produce sulphate of lime free from foreign or
gritty substances, not liable to detract from the value of paper or cotton cloths,
or damage the same when used in their manufacture, and not liable to injure the
same after they are manufactured, having a specific gravity about the same as
paper pulp, and much better than the artificial or natural sulphate of lime used
prior to this Invention, and it relates to the process of producing sulphate of lime
in the sulphate of lime produced by such process as a new article of manufacture,
and in one form of apparatus for carrying out this Invention.
In carrying out the Invention caustic lime and sulphuric acid of 66° Beaume,
preferably in the portions of sixteen parts of the former to twenty seven parts of
the latter.
The caustic lime is prepared preferably by first slaking the same in four times
its weight of water in a proper tank or vessel, and after it is thoroughly slaked
water is added enough to make ten pounds of water to one pound of line, thus
producing a good milk of lime, which is screened or strained to remove foreign
substances or grit.
The sulphuric acid is prepared preferably by mixing one part of the same with
six parts of water in a proper tank or vessel.
After the milk of line and sulphuric acid have been thus prepared they are
allowed to cool before being brought together to form sulphate of lime.
After they
are cool they are combined to form sulphate of lime by bringing them together in
streams that commingle and fall into a proper vat or vessel, or by placing them
together, or mixing them in a vat or vessel, or by causing them to flow together in
thin sheets and fall into a proper vat or vessel. When they are brought together
in streams that commingle, or are placed or mixed together in a vat or vessel, the
sulphate of lime produced is liable to be lumpy, and requires comminuting before it
can be properly used. When they are brought together in thin sheets the sulphate
of lime is free from lumps, and this mode of combining them is therefore preferred
to be used.
The sulphate of lime produced when either of these modes of combining the
prepared sulphuric acid and milk of lime is used is free from foreign substances or
grit, is about the specific gravity of paper pulp, and can be used as a filling in the
manufacture of paper, or as a dressing in the manufacture of cotton cloth with
better results than have been beretofore obtained by the use of artificial or natural
sulphate of lime heretofore employed.
It is obvious that the sulphate of lime thus produced may be used for other
purposes than those named.
The apparatus employed for carrying out the Invention is constructed and used
as follows:
A framework carries two platforms. On the platform of one is a tank placed for
containing the caustic lime and water used in slaking the same, which tank is
provided with a suitable cock or valve to draw off the milk of lime when ready.
A tank resting on the second platform is beneath the cock or valve to receive
the milk of lime after it has been properly prepared, as before described, and is
provided with a suitable cock or valve for drawing off the milk of lime after being
strained to combine with the sulphuric acid. A sieve or strainer capable of being
removed for cleaning rests on top of this tank under the cock or valve. Through
this strainer the milk of lime passes and is thus freed from foreign substances or grit
before entering the tank.
Another tank resting on the second platform for containing the sulphuric acid is
provided with a suitable cock or valve to draw off the acid to combine with the
milk of lime.
There is a tank for receiving the sulphate of lime produced by the combining of
the sulphuric acid and milk of lime.

page_text: Pans are placed under the cocks respectively, each provided with an apron to
spread the milk of lime and sulphuric acid in thin sheets, and direct them as they
issue from the pans, so that the sulphuric acid and milk of lime will combine
These pans.
effectually when they come in contact after falling from the aprons.
rest upon a support over the tank for receiving the sulphate of lime produced, said
support having an opening through which the sulphuric acid and milk of lime fall
forming sulphate of lime, which is caught by the tank. A stirrer can be used in
this latter tank if desired.
In using this apparatus, place in the tank first named the caustic lime and water,
preferably in the proportions above stated, and after it is thoroughly slaked add a
further quantity of water, as before described; then draw off the milk of lime thus
produced through the cock into the sieve, through which it passes into the next
tank, being thus freed from foreign substances and grit. Place the sulphuric acid and
water in the one tank, preferably in the proportions before stated, and allow it and
the milk of lime in the other tank to cool; then draw off the milk of lime through
the cock, allowing it to flow into the first pan, and the sulphuric acid through the
cock, allowing it to flow into the second pan. From these pans the milk of lime
and sulphuric acid flow over the aprons in thin sheets, and meeting combine, forming
From this
sulphate of lime, which falls in to the receiving tank in a pulpy mass.
tank it can be taken in the condition in which it exists therein for use in the filling
of paper, in the dressing of cloth, and for other purposes, or it can be pressed into
cakes, and thus readily shipped to users.
When the milk of lime and sulphuric acid are brought together in streams that
commingle, or are placed together or are mixed in a vat or vessel, the lumpy
sulphate of lime thus produced after being comminuted can be used or pressed into
cakes for use.
I do not confine myself to the exact proportions of sulphuric acid and caustic
lime above given, or the exact proportions of the sulphuric acid and the lime with
water in their preparation above recited, as they may be varied. These proportions
however should be such as to enable the sulphuric acid and milk of lime to combine
together and produce sulphate of lime, either neutral, which the proportions above
given will effect, for a filling for paper and dressing for cotton cloth, or for uses
other than for filling paper or for dressing cotton cloth not neutral.
This sulphate of lime is a beautiful pearl white color, free from grit, of a specific
gravity much lighter than the natural or artificial sulphate of lime used prior to
It is
this Invention, and is readily distinguishable in the market from the same.
particularly useful as a filling for the finer grades of writing and printing paper,
and can be employed in place of terra alba, Paris-white, the natural sulphate of
lime, the artificial sulphate of lime used prior to this Invention, and as a substitute
for china clay used for dressing cotton cloths.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William Morgan-Brown in the Great Seal Patent Office on the
11th May 1880.
WILLIAM MORGAN-BROWN, of the Firm of Brandon and Morgan-Brown, Engineers
and Patent Agents, of 38, Southampton Buildings, London, and 1, Rue Laffitte,
Paria. "IMPROVEMENTS IN THE MANUFACTURE OF SULPHATE OF LIME, IN THE
APPARATUS EMPLOYED THEREIN, AND IN THE ARTICLE OF MANUFACFURE
PRODUCED THEREBY.' A communication from abroad by Zenas C. Warren, of
New York, United States of America.
"
This Invention of improvements in the manufacture of sulphate of lime relates
to the manufacture and to an improved product. Previously to this Invention
artificial sulphate of lime had been made by dissolving carbonate of lime in muriatic
acid, then precipitating it with sulphuric acid or by a soluble sulphate, and then
treating it to successive washings to remove the free acid. Unless great care was
taken in the washing and even then traces of the acid were liable to remain, and
thus render it unsafe to use as a filling in the manufacture of paper, as a dressing
for cotton cloth and other articles which the acid would attack and damage. It
was also expensive to manufacture.
Natural sulphate of lime as calcined gypsum before it could be used as a filling
for paper had to be comminuted, which it was difficult to do properly, and then it
was liable to contain crystals, which in the manufacture of paper appeared in spots
in the latter after calendering.
Other objections existed to the use, especially as a filling for paper, of both
artificial and natural sulphate of lime prior to this Invention, the principle one of
which was that their specific gravity was greater than that of the paper pulp,
which caused them to settle when mixed in a fluid state with the paper pulp, and
thus waste in the bottoms of the vats and through the wire cloth of the paper
machine.
The object of this Invention is to produce sulphate of lime free from foreign or
gritty substances, not liable to detract from the value of paper or cotton cloths or
damage the same when used in their manufacture, and not liable to injure the same
after they are manufactured, having a specific gravity about the same as paper
pulp, and much better than the artificial or natural sulphate of lime used prior to
this Invention, and it relates to the process of producing sulphate of lime in the
sulphate of lime produced by such process as a new article of manufacture, and in
one form of apparatus for carrying out the Invention.
In carrying out the Invention caustic lime and sulphuric acid of 66° Beaumé,
preferably in the proportions of 16 parts of the former to twenty-seven parts of the
latter.
The caustic lime is prepared preferably by first slaking the same in four times
its weight of water in a proper tank or vessel, and after it is thoroughly slaked
water is added enough to make ten pounds of water to one pound of lime, thus
producing a good milk of lime which is screened or strained to remove foreign
substances or grit.
The sulphuric acid is prepared preferably by mixing one part of the same with
six parts of water in a proper tank or vessel.
After the milk of lime and sulphuric acid have been thus prepared they are
allowed to cool before being brought together to form sulphate of lime. After they
are cool they are combined to form sulphate of lime by bringing them together in
streams that commingle and fall into a proper vat or vessel, or by placing them
together, or mixing them in a vat or vessel, or by causing them to flow together in
thin sheets and fall into a proper vat or vessel. When they are brought together
in streams that commingle, or are placed or mixed together in a vat or vessel, the

page_text: sulphate of lime produced is liable to be lumpy and requires comminuting before it
can be properly used. When they are brought together in thin sheets the sulphate
of lime is free from lumps, and this mode of combining them is therefore preferred
to be used.
The sulphate of lime produced when either of these modes of combining the
prepared sulphuric acid and milk of lime is used is free from foreign substances or
grit, is about the specific gravity of paper pulp, and can be used as a filling in the
manufacture of paper, or as a dressing in the manufacture of cotton cloth, with
better results than have been heretofore obtained by the use of artificial or natural
sulphate of lime heretofore employed.
It is obvious that the sulphate of lime thus produced may be used for other
purposes than those named.
The apparatus employed for carrying out the Invention is constructed and used
as follows:-
In the Drawings Figure 1 is a front elevation of the apparatus; Figure 2 is a
plan view of the same; Figure 3 is a sectional view of part of the same on an
enlarged scale.
On the
I represents the frame-work, to which are secured two platforms 2, 3.
platform 2 a tank 4 is placed for containing the caustic lime and water used in
slaking the same, which tank is provided with a suitable cock or valve 5. to draw
off the milk of lime when ready,
6 is a tank resting on the second platform 3 beneath the cock or valve 5 to
receive the milk of lime after it has been properly prepared, as before described,
and is provided with a suitable cock or valve 7 for drawing off the milk of lime
after being strained to combine with the sulphuric acid. A sieve or strainer 8,
capable of being removed for cleaning, rests on top of this tank 6 under the cock
or valve 5. Through this strainer the milk of lime passes, and is thus freed from
foreign substances or grit before entering the tank 6.
9 is a tank resting on the platform 3 for containing the sulphuric acid, provided
with a suitable cock or valve 10 to draw off the acid to combine with the milk of
lime.
11 is a tank for receiving the sulphate of lime produced by the combining of the
sulphuric acid and milk of lime.
12 and 13 are pans placed under the cocks 7 and 10 respectively, each provided
with an apron 14 to spread the milk of lime and sulphuric acid in thin sheets, and
direct them as they issue from the pans 12 and 13, so that the sulphuric acid and
milk of lime will combine effectually when they come in contact after falling from
the aprons. These pans 12 and 13 rest upon a support 15 over the tank 11, said
support having an opening 16, through which the sulphuric acid and milk of lime
fall, forming sulphate of lime, which is caught by the tank 11. A stirrer can be
used in this latter tank if desired.
In using this apparatus place in the tank 4 the caustic lime and water, pre-
ferably in the proportions above stated, and after it is thoroughly slaked add a
further quantity of water, as before described; then draw off the milk of lime thus
produced through the cock 5 into the sieve 8, through which it passes into the next
tank 6, being thus freed from foreign substances and grit. Place the sulphuric acid
and water in the tank 9, preferably in the proportions before stated, and allow it
and the milk of lime in the tank 6 to cool; then draw off the milk of lime through
the cock 7, allowing it to flow into the pan 12, and the sulphuric acid through the
cock 10, allowing it to flow into the pan 13. From these pans the milk of lime
and sulphuric acid flow over the aprons 14 in 'thin sheets, and meeting_combine,
forming sulphate of lime, which falls into the tank 11 in a pulpy mass. From this
tank it can be taken in the condition in which it exists therein for use in the filling
of paper, in the dressing of cloth, and for other purposes, or it can be pressed into
cakes and thus readily shipped to users.
When the milk of lime and sulphuric acid are brought together in streams that
commingle, or are placed together, or are mixed in a vat or vessel, the lumpy

page_text: sulphate of lime thus produced after being comminuted can be used or pressed into
cakes for use.
I do not confine myself to the exact proportions of sulphuric acid and caustic lime
above given, or the exact proportions of the sulphuric acid and the lime with water
in their preparation above recited, as they may be varied. These proportions
however should be such as to enable the sulphuric acid and milk of lime to combine
together and produce sulphate of lime, either neutral, which the proportions above
given will effect for a filling for paper and a dressing for cotton cloth, or for uses
other than for filling paper or for dressing cotton cloth not neutral.
It is
This sulphate of lime is a beautiful pearl white-colour, free from grit, of a specific
gravity much lighter than the natural or artificial sulphate of lime used prior to
this Invention, and is readily distinguishable in the market from the same.
particularly useful as a filling for the finer grades of writing and printing paper,
and can be employed in place of terra alba, Paris-white, the natural sulphate of
lime, the artificial sulphate of lime used prior to this Invention, and as a substitute
for china-clay used for dressing cotton cloths.
Having now described and particularly set forth the nature of the said Inven-
tion, and the manner of carrying the same into effect, I would have it understood
that what I claim is,―
1st. The process of producing sulphate of lime by first preparing the milk of lime
and sulphuric acid in proper combining proportions, then allowing them to cool, and
then bringing them together, substantially as described.
2nd. The process of producing sulphate of lime by first preparing the milk of
lime and sulphuric acid in proper combining proportions, then allowing them to
cool, and then bringing them together in thin sheets, substantially as described.
3rd. I claim as a new article of manufacture sulphate of lime produced by first
preparing the milk of lime and sulphuric acid in proper proportions, then allowing
them to cool, and then bringing them together, substantially as described.
4th. The combination of the tanks 4, containing the sulphuric acid and milk of
lime, with pans each provided with an apron for spreading the acid and milk of
lime in thin sheets, substantially as described.
5th. The pans provided with aprons arranged in the manner substantially as and
for the purpose described.
6th. The combination of the tank 4 with the strainer 8 and tank 6, substantially
as and for the purpose described.
In witness whereof, I, the said William Morgan-Brown, have hereunto set my
hand and seal, this Tenth day of May, in the year of our Lord One thousand
eight hundred and eighty.
WILLIAM MORGAN-BROWN. (L.S.)