IMPROVEMENTS IN THE COMMERCIAL MANUFACTURE OF SULPHATE OF AMMONIA
Year: 1869

page_text: LETTERS PATENT to Frederick Braby, of Camberwell, in the County
of Surrey, for the Invention of "IMPROVEMENTS IN THE COMMERCIAL
MANUFACTURE OF SULPHATE OF AMMONIA."
Scaled the 20th June 1869, and dated the 16th January 1860.
PROVISIONAL SPECIFICATION left by the said Frederick Braby at
the Office of the Commissioners of Patents, with his Petition, on the
16th January 1869.
I, FREDERICK BRADY, of Camberwell, in the County of Surrey, do
hereby declaro the nature of the said Invention for "IMPROVEMENTS IN
THE COMMERCIAL MANUFACTURE OF SULPHATE OF AMMONIA," to be as follows:-
My Invention consists principally in the employment of copperas or
green vitriol in the manufacture of sulphate of ammonia for commercial

page_text: purposes instead of using sulphuric acid for that purpose as has hitherto
boon generally practised.
For this purpose, according to one process, the copperas is reduced to
a solution by water, to facilitate which it may be ground or pulverized,
and it is then added to gas liquor; or the copperas may be reduced to a
solution by means of the gas liquor itself.
According to another process ammonia is distilled from any solution
in which it may be held in an iron boiler containing lime in order to
remove from the ammonia sulphuretted hydrogen and other impurities.
The ammonia, by the action of heat and agitation, is liberated from the
gas liquor or other solution, and is conveyed through a bent pipo into a
vat containing sulphate of iron, the ammonia gas being made to pass on
its way thither through an intermediate washer or purifier containing
lime water.
According to a third process, and which I prefer to employ, the 1
ammonia is liberated from the gas liquor or other solution and conveyed
to the sulphato of iron by the blowing process for which Letters Patent
have been granted to myself and I. Baggs, bearing date the 27th June
1868, No. 2067, whereby a more rapid separation of the ammonia is
effected.
In either of the before-described processes heat may be applied with
advantago by means of hot air or steam pipes introduced into the
receptacles containing the liquor to assist decomposition or evaporation.
In either of the above processes when the union of the sulphate of
iron and ammonia takes place a chemical decomposition ensues, oxide
of iron being formed and precipitated and sulphate of ammonia remaining
in solution, which is filtered and then run into evaporating pans for
crystallization.
The iron oxide is washed and calcined, and. may be employed for
purifying gas, for forming a pigment, or it may be reduced to the state a
of "crocus martus," "colcothar," or jeweller's rouge, according to the
degrees of heat to which it is subjected, as is well understood.

page_text: "
•
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Frederick Braby in the Great Scal Patent Office
'on the 15th July 1809.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, FREDERICK
BRADY, of Camberwell, in the County of Surrey, send greeting.
WHEREAS Hor most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Sixteenth day of January, in the year
of our Lord One thousand eight hundred and sixty-nino, in the thirty-
second year of Her reign, did, for Hersalf, Hor heirs and successors,
give and grant unto me, the said Frederick Braby, Her special licenco
that I, the said Froderick Braby, my executors, administrators, and
assigns, or such others as I, the said Froderick Braby, my.exccutors,
administrators, and assigns, should at any time agreo with, and no others,
from time to time and at all times thereafter during the term therein
expressed, should and lawfully might make, uso, 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 COM-
MERCIAL MANUFACTURE OF SULPHATE OF AMMONIA," upon the condition (amongst
others) that I, the said Frederick Braby, my executors or administrator's,
by an instrument in writing under my, or their, or one of their hands and
scals, should particularly describe and ascertain the nature of the said
Invention, and in what mannor the same was to bo performed, and
causo the samo to be filed in the Great Scal Patent Office within
six calendar months next and immediately after the date of the said
Letters Patont.
NOW KNOW YE, that I, the said Frederick Braby, do hereby declaro
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, that is to say :-
My Invention consists principally in the employment of copperas or
green vitriol in the manufacture of sulphate of ammonia for commercial
purposes instead of using sulphuric acid for that purpose as has hitherto
been generally practised.
For this purpose, according to ono process, the copperas is reduced to
a solution by water, to facilitate which it may be ground or pulverized,

page_text: and it is then added to gas liquor; or the copperas may be reduced to a
solution by means of the gas liquor itself.
According to another process ammonia is distilled from any solution
in which it may be held in an iron boiler containing lime in order to
remove from the ammonia sulphuretted hydrogen and other impurities.
The ammonia, by the action of heat and agitation, is liberated from the
gas liquor or other solution, and is conveyed through a bent pipe into a
vat containing sulphate of iron, the ammonia gas being made to pass on
its way thither through an intermediate washer or purifier containing
lime water.
According to a third process, and which I prefer to employ, the
ammonia is liberated from the gas liquor or other solution and conveyed
to the sulphate of iron by the blowing process for which Letters Patent
have been granted to myself and I. Baggs, bearing date the 27 June
1868, No. 2067, whereby a more rapid separation of the ammonia is
effected.
In either of the before-described processes heat may be applied with
advantage by means of hot air or steam pipes introduced. into the
receptacles containing the liquor to assist decomposition or evaporation.
In either of the above processes when the union of the sulphate of
iron and ammonia takes place a chemical decomposition ensues, oxido
of iron being formed and precipitated and sulphate of ammonia remaining
in solution, which is filtered and then run into evaporating pans for
crystallization.
The iron oxide is washed and calcined, and may be employed for
purifying gas, for forming a pigment, or it may be reduced to the stato
of "crocus martus," "colcothar," or jeweller's rouge, according to the
degrees of heat to which it is subjected, as is well understood.
1
Having thus set forth the nature of my Invention, I will now
proceed more particularly to describe the manner of performing the
samo.
In carrying out the first-described process the gas liquor may be kept
in a reservoir of metal or wood, or better still in an excavation in the
ground; the bottom of such excavation should have two courses of
bricks upon one foot of concrete, and be lined inside with flat red tiles;
the sides should be lined with 14-inch bricks and tiles inside, and the

page_text: concrete rammed in outside, the reservoir to have a low arched roof of
two courses of bricks. The sulphate of iron is contained in a largo
wooden vat or tank, and into which the gas liquor is pumped. Deconi-
position ensues, the ammonia of the gas liquor combining with the
sulphuric acid of the iron salt. Sufficient time is allowed for settlement,
and the sulphate of ammonia is run out on to large shallow wooden
filters. These filters have a false bottom two inches from the bottom
made of one-inch deal 'full of half-inch drilled and burnt holes, and
supported by longitudinal fillets or laths; on this false bottom will be
placed huckaback or other strong draining cloth; the liquid after
draining through this is conducted down into iron evaporators. by
means of pipes in each filter; it is then boiled down and crystallized.
The iron oxide remaining on the brown sheeting or canvas-is then well
washed by water from a cistern on a higher level, kept for the purpose.
The first washing or water draining through the oxide will remove from
it sufficient ammonia to be worth running into the evaporating pans,
especially when the blowing principle is adopted, as mentioned below;
the iron oxide is then thrown on a flat kiln for drying, by which means
moisture and any sulphur and carbonic acid are expelled. The sulphate
of ammonia after having been boiled down to the requisite consistency
is run into Icad-lined or other pans for crystallization.
In carrying out the second-described process the gas liquor is pumped
up from the reservoir into a large iron still or boiler set in brickwork. A
quantity of lime is put in the still in order to neutralize the sulphuretted
hydrogen, carbonic acid, or other impurities of the gas liquor by means
of heat, and by means of an agitator with fans rapidly revolving insido
the still the ammonia gas is liberated and passes through a pipe into a
wooden vessel to be called a "washer" or "purifier," and which con-
tains limo and water at the bottom. A bent pipe brings the ammonia
to nearly the bottom of the liquid, the lime of which tends to deprivo it
of any sulphuretted hydrogen or other remaining impurity. This washer
is a closed vessel and soon becomes full of the gas, which passes theńco
through pipes into a vat or vats containing the sulphate of iron. The
purifier is fitted with a false bottom perforated with holes larger and
more numerous as they radiate from the centre. Underneath this falso
bottom is also a stirrer actuated by gearing from the top. Some vapour
of water may come from the still with the ammonia, but will be con-

page_text: densed in the washer. The washer is provided with a safety pipe and
with a pipe to lead back into the boiler, also with a tap to ascertain the
height of liquid. The decomposing vats are preferably made of fir
strongly hooped, provided with perforated false bottoms about six inches
from the bottom, the perforations increasing as they radiate from the
inlet: The ammonia enters by a tube bringing it under the false bottom
so that the decomposition would take place there first; it would then
pass through the holes and spread itself over the whole surface of the
liquor; the vats may be also provided with stirrers. When perfect
decomposition has taken place the whole is after a short time run on
to the filters, as before described, and the ammoniacal salt run into
ovaporating pans; when these are occupied the surplus fluid can bo
retained in a reservoir tank; the process is then completed as in the
first process described. When the lime in the washer becomes impure
or wears out a plug is taken out and the mud run into the still to be
further used in decomposing the gas liquor. A much larger quantity
of gas liquor will generally be required than of the iron solution, but
this will depend upon the relative strength of each.
By means of testing the specific gravity with a Twaddle, or by testing
what quantity of sulphuric acid will be required to neutralize ono gallon
of the gas liquor, it will be easy by taking account of the chemical
equivalents of each solution to precisely determine the quantity of each
that will be needed for each charge. As to the still the impuritics would
be allowed to settle for an hour or two, and the contents then cleared
out.
The application of the blowing process, as described in the Specifi-
cation to Baggs and Braby's Patent, before mentioned, to the liberating
of the ammonia from the gas liquor or other solution, and the conveying
of such ammoniacal vapour to the sulphate of iron, may be employed
with advantago in connection with either of the two before-described:
processes, and heat may, as before stated, also be employed with advan-
tage in either case to accelerate the decomposition or evaporation, such
heat being conveniently applied by means of hot air, steam, or water
circulating through iron or lead pipes immersed in the fluid to bo
acted upon.
Having thus described the nature of my Invention, and in what
manner the same is to bo performed, I wish it to be understood that

page_text: what I claim under the herein-before in part recited Letters Patont is,
the before-described processes for the commercial manufacture of
sulphate of ammonia wherein the ammonia contained in gas liquor
or other solutions is caused to act upon and decompose copperas or
sulphato of iron, substantially as herein-before set forth.
In witness whereof, I, the said Frederic Braby, havo harcunto
set my hand and scal, this Tenth day of July, in the year of
our Lord One thousand cight hundred and sixty-nino.
FREDERICK BRABY. (L.S.)
Witness,
JNO. MILLARD.