IMPROVEMENTS IN THE MANUFACTURE OF MANURES
Year: 1873

page_text: LETTERS PATENT to John McDougall, of the Firm of McDougall
Brothers, of Manchester and London, Manufacturing Chemists, for
the Invention of "IMPROVEMENTS IN THE MANUFACTURE OF MANURES."
Scaled the 25th March 1873, and dated the 1st February 1873.
PROVISIONAL SPECIFICATION left by the said Jolin M'Dougall at the
Office of the Commissioners of Patents, with his Petition, on the
1st February 1873.
J, JOHN M.DOUGALL, of the Firm of McDougall Brothers, of
Manchester and London, Manufacturing Chemists, do hereby declare
the nature of my said Invention for "IMPROVEMENTS IN THE MAnufacture
OF MANURES," to be as follows :
-
This Invention has for its object improvements in the manufacture
of manures.
I treat phosphatic substances with sulphuric acid to render them
soluble and remove the soluble constituents (either whole or in part) by
washing, filtration, or other convenient method, and into the resulting

page_text: solution I pass liquids, gases, or vapours containing ammonia, and the
resulting product may be concentrated or dried by exposure or heat.
Or, after passing ammonia into the resulting solution as herein described,
I allow the precipitated phosphate of lime to subside, and separate the
liquid, which can be evaporated into a salt. The precipitated phosphate
can be dried for use or incorporated in the semi-liquid state in the
manufacture of superphosphates as hereafter described. The solution
obtained as herein described may be used for the removal of ammonia in
coal gas or other gases arising from the destructive distillation of
carbonaceous substances by employing it in the ordinary washers or
scrubbers in use in gas works, or by other convenient method.
I also treat phosphatic substances with hydrochloric acid in any
desired quantity to render them soluble, if sufficient of the acid has been
added to convert the phosphate into the liquid state any insoluble
residue may or may not be removed by subsidence or other convenient
method, and into the mass or liquid I pass gases or vapours containing
ammonia other than coal gas. The resulting product can be con-
centrated by heat or exposure. Or, in treating the phosphatic substances
with hydrochloric acid as above described, I take care the acid is
of reduced strength, or if acid of full strength is used the resulting
solution may be diluted, so that after passing in the gases or vapours
containing ammonia the resulting solution shall not be too dense to
allow the soluble phosphate that has become changed into precipitated
phosphate to subside, so that the liquid may be run off and evaporated
into a salt, and the precipitated phosphate dried for use.
In the manufacture of superphosphate of lime for manure, when
sulphuric acid is used, it is customary to dilute the acid with water
when bringing it into contact with the phosphate to be acted upon, by
which means a drier product is obtained than if acid alone were
employed. This water, either whole or in part, I substitute with liquids
or semi-liquids containing ammonia or other useful manurial ingredients
and so utilize them, at the same time obtaining a manure of sufficient
dryness. If the liquid used requires the addition of an acid for its
proper utilization the acid must be added to it before using, or oxtra
acid added to the phosphate. After the removal of the soluble con-
stituents from the phosphatic substances treated with sulphuric acid as
already described, the rosiduo will consist to a largo extent of sulphate of
limc. This sulphate of lime or sulphate of lime obtained by other

page_text: methods, or in a natural state, or chloride of calcium I treat with
liquids containing ammonia, and whilst agitated pass in carbonic acid,
which causes the decomposition of the sulphates or chlorides and
liberates the acids to combine with the ammonia. After subsidence I
separate the resulting solution and evaporate it into a salt.
The carbonic acid generated in the treatment with an acid of phos-
phatic substances containing carbonate of lime may be utilized for this
purpose, or may be derived from other convenient source.
When it is desirable to convert the precipitated phosphates obtained
by the foregoing processes again into soluble phosphates, cither wholly
or in part, I add sulphuric or any suitable acid to effect this purposc.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John M'Dougall in the Great Scal Patent Office,
on the 1st August 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, Jonn
MºDOUGALL, of the Firm of McDougall Brothers, of Manchester and
London, Manufacturing Chemists, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the First day of February, in the year
of our Lord One thousand eight hundred and seventy-three, in the
thirty-sixth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said John McDougall, Her special
license that I, the said John McDougall, my executors, administrators,
anil assigns, or such others as I, the said John McDougall, my
executors, administrators, or 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 Kingdom of Great Britain and Ireland,
the Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS
IN THE MAGUFACTURE OF MANURES," upon the condition (amongst others)
that I, the said John McDougall, my executors or administrators, by
an instrument in writing under my hand and seal, should particularly
describe and ascertain the nature of the said Invention, and in what

page_text: 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 John McDougall, do hereby declaro
the nature of my said Invention, and in what manner the same is
to be performed, to be particularly described and ascertained in and by
the following statement, that is to say:-
My said Invention has for its object improvements in the manufacturo
of manures.
I treat phosphatic substances with sulphuric acid to render them
soluble and remove the soluble constituents (either whole or in part) by
washing, filtration, or other convenient method, and into the resulting
solution I pass liquids, gases, or vapours containing ammonia, and the
resulting product may be concentrated or dried by exposure or licat,
and is then applicable to the manufacture of manures. Or, after passing
ammonia into the resulting solution as herein described I allow the
precipitated phosphate of lime to subside and separate the liquid, which
can be evaporated into a salt. The precipitated phosphate can be dried
for use or incorporated in the semi-liquid state in the manufacture of
superphosphates as herein-after described. The solution obtained as
herein described may be used for the removal of ammonia in coal gas or
other gases arising from the destructive distillation of carbonaceous sub-
stances, by employing it in the ordinary washers or scrubbers in use in gas
works, or by other convenient method, or it may be used for absorbing
ammonia existing in gases or vapours derived from other sources.
I also treat phosphatic substances with hydrochloric acid in any
desired quantity to render them soluble, if sufficient of the acid has been
added to convert the phosphate into the liquid state any insoluble
residue may or may not be removed by subsidence or other convenient
method, and into the mass or liquid I pass gases or vapours (other than
coal gas) containing ammonia. The resulting product can be con-
centrated by heat or exposure, and employed as aforesaid. Or, in
treating the phosphatic substances with hydrochloric acid as above
described I take care the acid is of reduced strength, or if acid of full
strength is used the resulting solution may be diluted, so that after
passing in tho gases or vapours containing ammonia the resulting
solution shall not be too dense to allow the soluble phosphate that has

page_text: become changed into precipitated phosphate to subside, so that the
liquid may be run off and evaporated into a salt and the procipitated
phosphate dried for use.
In the manufacture of superphosphate of lime for manure, when
sulphuric acid is used, it is customary to dilute the acid with water when
bringing it into contact with the phosphate to be acted upon, by which
means a drier product is obtained than if acid alone were employed. For
this water, either whole or in part, I substitute liquids or semi-liquids
containing ammonia or other useful manurial ingredients, and so utilize
them, at the same time obtaining a manure of sufficient dryness. If the
liquid used requires the addition of an acid for its proper utilization, the
acid must be added to it before using, or extra acid added to the
phosphate. After the removal of the soluble constituents from the phos-
phatic substances treated with sulphuric acid as already described the
residue will consist to a large extent of sulphate of lime. This sulphate
of lime, or sulphate of lime obtained by other methods, or in a natural
state, or chloride of calcium, I treat with liquids containing ammonia,
and whilst agitated pass in carbonic acid, which causes the decomposition
of the sulphates or chlorides, and liberates the acids to combine with
the ammonia. After subsidence, I separate the resulting solution and
evaporate it into a salt.
The carbonic acid generated in the treatment with an acid of phos-
phatic substances containing carbonate of lime may be utilized for the
above purpose, or may be derived from other convenient sources.
When it is desirable to convert the precipitated phosphates obtained
by the foregoing processes again into soluble phosphates, either wholly
or in part, I add sulphuric or any suitable acid to effect this purpose.
Having now described and particularly ascertained the nature of my
said Invention and the manner in which the same is or may be used or
carried into effect, I would observe in conclusion that what I consider
to be novel and original and therefore claim as the Invention secured to
me by the herein-before in part recited Letters Patent is,―
First. The addition of ammonia to the solution derived from the
treatment of phosphatic substances with sulphuric acid, and the
absorption of ammonia from coal gas direct or from other gases or
vapours containing ammonia, in the manner and for the purposes hercin-
before described.

page_text: Second. The addition of ammonia in a gascous form (other than in
_coal gas) to phosphatic substances treated with hydrochloric acid, for
the purposes herein-before described.
Third. The employment in the manufacture of superphosphate of
lime of liquids or semi-liquids containing ammonia or other manurial {
ingredients instead of water (either wholly or partly).
Fourth. The treatment of sulphate of lime or suitable materials
containing it or chloride of calcium with ammonia and carbonic acid, so
as to render the acids contained in those materials available for the
purpose of combining with the ammonia.
In witness whereof, I, the said John M'Dougall, have to this my
Specification set my hand and scal, this Thirty-first day of July,
One thousand eight hundred and seventy-three.
TATTYY UNDATIA TT
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