IMPROVEMENTS IN THE MANUFACTURE OF CARBONATES OF SODA
Year: 1874

page_text: Sealed the 15th June 1875, and dated the 16th December 1874.
PROVISIONAL SPECIFICATION left by the said Ludwig Mond at the
Office of the Commissioners of Patents, with his Petition, on the
16th December 1874.
1, LUDWIG MOND, of Northwich, in the County of Chester, Manu-
facturing Chemist, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN THE MANUFACTURE OF CARBONATES OF SODA," to be as
follows:-
My Invention relates to that process in the commercial production of
carbonates of soda which is commonly known as the direct process by
ammonia, and has for its object a more ready and complete amalgama-
tion of the substances required to produce the desired effect. For this
purpose I cause the brine (from which the said carbonates are made) to
[Price Sd.]

page_text: be submitted in a finely divided state, as in a spray, to the action of
ammonia and carbonic acid. This I propose to do by using an apparatus
known as a spray producer, using carbonic acid gas to force forward the
brine into a suitable vessel; or the spray may be produced by forcing
the brine against a dead surface, the vapours or their equivalents being
present or simultaneously injected; these details may be varied so long
as the spray form of the brine is obtained; or the brine may first be
treated with ammonia in the usual manner, and the resulting ammoniacal
brine be submitted to the action of carbonic acid in the aforesaid manner.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Ludwig Mond in the Great Seal Patent Office
on the 16th June 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, Ludwig
MOND, of Northwich, in the County of Chester, Manufacturing Chemist,
send greeting.
of our
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Sixteenth day of December, in the year
Lord One thousand eight hundred and seventy-four, in the
thirty-eighth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Ludwig Mond, Her special
license that I, the said Ludwig Mond, my executors, administrators,
and assigns, or such others as I, the said Ludwig Mond, 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, exercise, and
vend, within the United Kindom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS
IN THE MANUFACTURE OF CARBONATES OF SODA," upon the condition (amongst
others) that I, the said Ludwig Mond, by an instrument in writing
under my hand and seal, 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 Ludwig Mond, do hereby declare
the nature of my said Invention, and in what manner the same is to be

page_text: performed, to be particularly described and ascertained in and by the
following statement :-
-
My Invention relates to that process in the commercial production of
carbonates of soda which is commonly known as the direct process by
ammonia, and has for its object a more ready and complete amalgama-
tion of the substances required to produce the desired effect. For this
purpose I cause the brine (from which the said carbonates are to be
made) to be submitted in a finely divided state to the action of ammonia
and carbonic acid. The finely divided state I refer to is that which may
be described as a spray, and I produce it in a form as nearly like mist
as possible. This may be done by using apparatus known as a spray
producer, but using carbonic acid gas to effect the spray of brine and to
force it forward into a suitable vessel; or the spray may be produced by
forcing the brine violently against a dead surface, or by any other known
means, the vapours of ammonia and carbonic acid or their equivalents
being present or simultaneously injected. By another method the brine
may first be treated with ammonia in the usual manner, and the resulting
ammoniacal brine be submitted in the spray form to the action of car-
bonic acid. These details however may be varied so long as the spray
form is maintained, but as an illustration I will describe one arrange-
ment I employ in carrying my Invention into practice. In this
arrangement I use a series of two or more vessels, the carbonic acid gas
(produced by preference from a lime kiln) being forced under pressure
by means of a blowing engine into the first of these vessels, and passing
from one to another until it leaves the last of the series, while the
ammoniacal brine enters the last vessel passing in the opposite way, and
out of the first one. In this manner a more complete absorption of the
gas and a
more complete saturation of the ammoniacal brine are
obtained.
The pressure of the gas in the various vessels is so regulated by means
of valves or other suitable apparatus that it is highest in the first of
them and smaller in every following one, so that the gas rushes from
one into the other at a sufficient speed to divide into a spray the
ammoniacal brine with which it comes in contact, and which is carried
with it, the operation being similar to that of the apparatus known as
Giffard's injector used in feeding steam boilers, the velocity being suffi-
cient to draw the liquid from one vessel to another, but this may be
assisted by applying pumps between each of two vessels, or by placing

page_text: the said vessels at different levels. I prefer to use cast or wrought iron
vessels of considerable height in proportion to their width, and 1 intro-
duce the gas and liquor at or near the bottoms of the said vessels, and
cause them to pass in a vertical direction, and I take the gas out again a
few feet above the bottom, so that it rushes up to the top and then
descends again before leaving the vessel. The vessels are fitted with
agitators for the purpose of keeping the bicarbonate of soda formed in
suspension in the liquid that accumulates on the bottom. After leaving
the last vessel the gas still holds liquid in suspension, and 1 then pass it
into one or more vessels which I call washers, and which are partially
filled with the liquid from the first of the above mentioned series of
vessels, and I force it through this last-named liquid so as to retain any
liquid which the gas holds in suspension, and also any ammoniacal gas
which it contains. The saturated liquid which is so obtained I treat as
usual to separate the bicarbonate of soda which it holds in suspension,
and to recover the ammonia which it contains.
Having thus described and ascertained the nature of my said Inven-
tion, and the manner in which the same is to be performed, I desire it
to be understood that I claim as secured to me under the above in part
recited Letters Patent and for the purpose above set forth, submitting
the brine to ammonia and carbonic acid, or the ammoniacal brine to
carbonic acid in the form of a spray or mist.
In witness whereof, I, the said Ludwig Mond, have hereunto set
my hand and seal, this Fifteenth day of June, in the year of our
Lord One thousand eight hundred and seventy-five.
LUDWIG MOND. (L.S.)