IMPROZENT IN QUE MANDRA CHUDE OF MANHIDE
Year: 1872

page_text: LETTERS PATENT to John M'Dougall, of the Firm of M'Dougall
Brothers, of Manchester and London, Manufacturing Chemists, for
the Invention of " IMPROZENT IN QUE MANDRA CHUDE OF MANHIDE"
Scaled the 25th February 1873, and dated the 21st September 1872.
PROVISIONAL SPECIFICATION left by the said John McDougall at the
Office of the Commissioners of Patents, with his Petition, on the
21st September 1872.
I, 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 the absorption by means of acid
superphosphate of lime made by the addition of sulphuric acid to
phosphatic substances of the ammonia and salts of ammonia contained
in the gases and vapours arising from the destructive distillation of
carbonaceous substances.
I employ an acid superphosphate of lime prepared by the addition of
sulphuric acid to phosphatic substances, and either mix with it sawdust
or any light porous material or not, as may be found necessary, to admit
of the passage through it of the gases and vapours arising from the
distillation of carbonaceous substances. The ammonia is absorbed and
the acid superphosphate of lime is changed into precipitated phosphate of

page_text: lime and sulphate of ammonia, and is in this condition well adapted for
use as a manure. As however the precipitated phosphate is not regarded
by all buyers as equal in market value to soluble phosphate I add a
quantity of sulphuric acid to the product thus obtained to render the
precipitated phosphate of lime soluble, and thus obtain a mixture of 5
soluble phosphate of lime and sulphate of ammonia which is a readily
saleable and valuable manure.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John McDougall in the Great Seal Patent Office on
the 18th March 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
M'DOUGALL, 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 Twenty-first day of September, in the year of our
Lord One thousand eight hundred and seventy-two, in the thirty-sixth
year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said John McDougall, Her special license that
I, the said John McDougall, my executors, administrators, and assigns,
or such others as I, the said John McDougall, my executors, adminis-
trators, 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 MANUFACTURE 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 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 declare
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 :-

page_text: My said Invention has for its object the absorption by means of acid
superphosphate of lime, made by the addition of sulphuric acid to phos-
phatic substances, of the ammonia and salts of ammonia contained in
the gases and vapours arising from the destructive distillation of carbon-
accous substances or ammoniacal vapours derived from other substances
or liquids.
I employ an acid superphosphate of lime prepared by the addition of
sulphuric acid to phosphatic substances, and either mix with it sawdust
or any light porous material or not, as may be found necessary, to admit
of the passage through it of the gases and vapours containing ammonia.
The ammonia is absorbed and the acid superphosphate of lime is for the
most part changed into precipitated phosphate of lime and sulphate of
ammonia, and is in this condition well adapted for use as manure.
I will now describe a method I prefer in carrying out my Invention :
-I make acid superphosphate of lime by the addition of sulphuric acid
to phosphatic substances, and if not sufficiently porous or light to admit
of gas and vapours passing through freely I mix with it sufficient saw-
dust or other suitable light porous material. If intended for the absorp-
tion of the ammonia contained in ordinary coal gas it is placed in the
ordinary purifiers in use at gas works in one or more layers. Whilst the
gas is passing through the ammonia is absorbed by the acid super-
phosphate, which thereby becomes for the most part changed into pre-
cipitated phosphate of lime and sulphate of ammonia, and is in this
condition well adapted for use as a manure.
I would observe that I am aware that it has been proposed to employ
a combination of phosphate of lime and a metal such as iron for the
purpose of removing both sulphuretted hydrogen and ammonia from
gas, but that process could not be rendered commercially remunerative
as the resulting product would in any case have been of very small
manurial value.
When the Invention is intended to be employed for the absorption of
ammonia in other processes, such as the utilization of the ammoniacal
liquor resulting from the condensation and washing of gas, and ordinarily
called "gas liquor," or the utilization of the ammonia from materials
containing ammonia, the following is one method that may be em-
ployed-The ammonia is driven off by any suitable means, such as the
heating the ammoniacal solution by applying heat externally to a retort

page_text: °
or vessel containing the said gas or ammoniacal liquor or ammoniacal
material, or by passing thereinto a jet of steam, with or without the
addition of lime, as is well understood, and the ammonia or ammoniacal
constituents driven off are passed through or over the acid superphos-
phate, exposed in suitable chambers on shelves or perforated trays 5
contained in a chamber so arranged as that the gas or vapours and
products may have free passage through or over the material: When
much moisture is driven off or over with the ammonia it may be
desirable to condense as much of the moisture as convenient before it
passes through or over the superphosphate, and for such purpposes 1
suitable condensing apparatus is employed.
When it is desirable to render the precipitated phosphates obtained by
the foregoing process again into soluble phosphates, cither whole or in
part, I add sulphuric or any suitable acid to effect this purpose.
I
Having now described and particularly ascertained the nature of my 1
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 absorption of ammonia contained in gases or vapours 2
arising from the destructive distillation of carbonaceous substances, or
produced from other ammoniacal substances, or from gas liquor or other
ammoniacal liquors, by the employment of an acid superphosphate of
lime, in the manner and for the purposes as hercin-before described.
Second. The addition of sulphuric or any suitable acid to the products 2
as above obtained for the purpose of rendering the phosphate again into
soluble phosphate as far as may be desired.
In witness whereof, I, the said John McDougall, have to this my
Specification set my hand and seal, this Seventeenth day of March,
One thousand eight hundred and seventy-three.
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