IMPROVEMENTS IN THE TREATMENT OF AMMONIACAL LIQUOR FOR THE SEPARATION OF AMMONIA COMPOUNDS THERE- FROM
Year: 1878

page_text: LETTERS PATENT to John Imray, of Southampton Buildings, in the County
of Middlesex, for the Invention of "IMPROVEMENTS IN THE TREATMENT OF
AMMONIACAL LIQUOR FOR THE SEPARATION OF AMMONIA COMPOUNDS THERE-
FROM."
A communication from abroad by Henry Joseph Ernest Hennebutte,
of Anglet, near Bayonne, and Charles Just Felix Raoul de Jeannel Mesnard,
Viscomte de Vaureal, of Biarritz, France.
Scaled the 15th April 1879, and dated the 29th October 1878.
PROVISIONAL SPECIFICATION left by the said John Imray at the Office of
the Commissioners of Patents on the 29th October 1878.
TIME-
JOHN IMRAY, of Southampton Buildings, in the County of Middlesex.
PROVEMENTS IN THE TREATMENT OF AMMONIACAL LIQUOR FOR THE SEPARATION OF
AMMONIA COMPOUNDS THEREFROM." [A communication from abroad by Henry
Joseph Ernest Hennebutte, of Anglet, near Bayonne, and Charles Just Felix Raoul
de Jeannel Mesnard, Viscomte de Vaureal, of Biarritz, France.]
The ammoniacal liquors produced at gas works are usually so dilute that there
is no economical advantage in transporting them for use. They have been treated
on the spot for the production of crude sulphate of ammonia, but the process for
this purpose demands considerable plant and careful superintendance, and is objec-
tionable on account of the dangers attending the use of the sulphuric acid employed.
This Invention consists in a cheap and easy process whereby ammonia compounds
in a state fit for transport can be readily produced from the ammoniacal liquor at
the gas works, without demanding special plant or care, and with the advantage of
utilising a portion of the waste heat of the gas furnaces. For this purpose, the
ammoniacal liquor is placed in a vessel, which may be a wooden cask placed
vertically, open at the head and having an outlet provided with a wooden or
earthenware spigot at about one-third of its height. In this vessel there is added
I Price AdI

page_text: a quantity of calcium chloride proportioned to the quantity of water in the liquor,
and the contents are well mixed by stirring. There is then added a small propor-
-tion of either chloride-of-iron-and-calcium, or-of-sulphate-of-iron-When-sulphate
-of-iron-is-used-it-is-suspended in-the-liquid-in a bag of open fabric.
After allowing
the mixture several hours to settle, the upper portion is run off by the cock into a
flat evaporating vessel of iron plate heated by the waste heat of the furnaces. It is
of advantage to put into the evaporator a small quantity of the double chloride of
ammonium and lead as this furnishes by deposit of lead a protecting surface on the
interior of the evaporator, rendering the use of lead lining unnecessary. The liquid
in the evaporator is concentrated to any desired degree, and is then ready to be
-disposed-of-for-use-
In the process above described the re-actions are as follows:-The carbonate of
ammonia in the liquor and the calcium chloride produce ammonium chloride or sal
ammoniac, insoluble carbonate of lime, and a portion of carbonic acid which escapes.
The hydrosulphate of ammonia and the sulphate of iron re-act, producing soluble
sulphate of ammonia and insoluble sulphide of iron; or, when chloride of iron is
used, the re-action gives ammonium chloride and sulphide of iron. The carbonate
of lime and sulphide of iron settle in a dense precipitate, leaving the solution of
ammonium chloride and sulphate of ammonia to be drained off and concentrated by
evaporation. If desired, the small quantity of sulphate of ammonia produced by the
re-action of sulphate of iron can be converted into ammonium chloride by any of
the well-known processes for that purpose.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said John Imray in the Great Seal Patent Office on the 25th April
1879.
88
JOHN IMRAY, of Southampton Buildings, in the County of Middlesex. IM-
PROVEMENTS IN THE TREATMENT OF AMMONIACAL LIQUOR FOR THE SEPARATION OF
AMMONIA COMPOUNDS THEREFROM." A communication from abroad by Henry
Joseph Ernest Hennebutte, of Anglet, near Bayonne, and Charles Just Felix Raoul
de Jeannel Mesnard, Viscomte de Vaureal, of Biarritz, France.
The ammoniacal liquors produced at gas works are usually so dilute that there is
no economical advantage in transporting them for use. They have been treated on
the spot for the production of crude sulphate of ammonia, but the process for this
purpose demands considerable plant and careful superintendance, and is objectionable
on account of the dangers attending the use of the sulphuric acid employed. This
Invention consists in a cheap and easy process whereby ammonia compounds in a
state fit for transport can be readily produced from the ammoniacal liquor at the
gas works without demanding special plant or care, and with the advantage of
utilising a portion of the waste heat of the gas furnaces. For this purpose, the
ammoniacal liquor is placed in a vessel, which may be a wooden cask placed verti-
cally, open at the head, and having an outlet provided with a wooden or earthenware
spigot at about one-third of its height. In this vessel there is added a quantity of
calcium chloride, proportioned to the quantity of water in the liquor, and the con-
tents are well mixed by stirring. There is then added a small proportion of either
chloride of iron, or of chloride of iron and calcium, or of sulphate of iron. When
sulphate of iron is used it is suspended in the liquid in a bag of open fabric. After
allowing the mixture several hours to settle, the upper portion is run off by the
cock into a flat evaporating vessel of iron plate, heated by the waste heat of the
furnaces. It is of advantage to put into the evaporator a small quantity of the
double chloride of ammonium and lead, as this furnishes by deposit of lead a pro-
tecting surface on the interior of the evaporator, rendering the use of lead lining
unnecessary. The liquid in the evaporator is concentrated to any desired degree
and is then ready to be disposed of for use.
In the process above described the re-actions are as follows:-The carbonate of
ammonia in the liquor and the calcium chloride produce ammonium chloride or sal
ammoniac, insoluble carbonate of lime, and a portion of carbonic acid which escapes.
The hydrosulphate of ammonia and the sulphate of iron re-act, producing soluble
sulphate of ammonia and insoluble sulphide of iron; or, when chloride of iron is
used, the re-action gives ammonium chloride and sulphide of iron. The carbonate
of lime and sulphide of iron settle in a dense precipitate, leaving the solution of
ammonium chloride and sulphate of ammonia to be drained off and concentrated by
evaporation until a solid skin of the salt is formed on the surface, which is sent in
that form to the works where it is to be utilised. The richness of this concentrated
liquor can be ascertained according to its density by means of a special table. The
calcium chloride employed for this re-action may be the residue from the manu-
facture of ammoniacal salts and liquid ammonia, or from any other chemical
manufacture which yields this salt as a waste product. The calcium chloride
might be forwarded to the gas works direct from the ammonia works, as might
also the double chloride of ammonium and lead. The application of this double
salt for the continuous coating of the evaporating vessels with lead renders the
process practicable without the use of special lead linings, which would not only be
more expensive but would be less durable than the coating produced as above
described.
In cases where sulphate of iron is used together with the calcium chloride it
would always be easy, by means of the well-known re-action of sea salt on sulphate

page_text: of ammonia to convert into ammonium chloride the small quantity of that substance
produced by the re-action of the sulphate of iron, if this were desired. Sulphate of
alumina may-also-be-employed-for-producing-sulphate-of-ammonia-from-the-
Cammoniacal liquor, the re-action being as follows:-The ammoniacal salts contained
in the liquor re-act upon the sulphate of alumina, producing sulphate of ammonia
in solution, carbonic and hydrosulphuric acids being disengaged, and an abundant
precipitate of hydrate of alumina being formed, which purifies the liquor from the
tarry matters. The use of the above-described Invention has the following advan-
tages in gas works:-By means thereof the ammoniacal liquors are rapidly and
easily transformed into a concentrated product readily transportable. The process,
_based_on_the_utilisation_of_the_waste heat_of_the_furnaces, requires only a small
amount of manual labour, avoids all use of acids, and requires only simple and
inexpensive apparatus, as a wooden barrel and a flat sheet-iron evaporating pan are
all that is requisite. With regard to the manufacturers of ammoniacal salts, this
process affords them a larger supply of the requisite materials under more advan-
tageous conditions, as the concentration is effected without cost at the gas works,
and as the principal chemical agent required for fixing the ammonia, namely the
calcium chloride, is easily transported and manipulated, and is generally obtained as
a waste product in the said works.
Having thus described the nature of this Invention, and in what manner the
same is to be performed, as communicated to me by my foreign correspondents, I
claim,―
First. The method, substantially as herein described, of producing ammonia
compounds from the ammoniacal liquors of gas works, whereby the liquor is treated
in a vessel first with calcium chloride and then with chloride of iron, or with the
double chloride of iron and calcium, or with sulphate of iron, substantially as
herein described.
Second. Effecting the concentration of the ammonia compounds produced as set
forth in the preceding claim, by evaporation in flat vessels heated by the waste heat
of the gas works, substantially as herein described.
Third. In the process set forth in the preceding claims, treating the ammoniacal
liquor with the re-agents in a wooden barrel having a cock at a certain height,
through which the resulting ammonia products are run off into sheet-iron evaporating
pans, a small quantity of the double chloride of ammonium and lead being added to
the liquid, substantially as and for the purposes herein described.
In witness whereof, I, the said John Imray, have hereunto set my hand and
seal, this Twenty-fifth day of April, in the year of our Lord One thousand
eight hundred and seventy-nine.
JOHN IMRAY. (L.S.)