IMPROVEMENTS IN THE MANUFACTURE OF ARTIFICIAL MANURE
Year: 1882

page_text: LETTERS PATENT to Herbert John Haddan, of Kensington, Middlesex for an
invention of IMPROVEMENTS IN THE MANUFACTURE OF ARTIFICIAL MANURE
A communication to him from abroad by Theodor Richters, of Breslau,
Germany
PROVISIONAL SPECIFICATION left by the said Herbert John Haddan at the
Office of the Commissioners of Patents on the 20th June 1882.
HERBERT JOHN HADDAN, of Kensington, Middlesex, "IMPROVEMENTS IN
THE MANUFACTURE OF ARTIFICIAL MANURE," a cominunication to me from abroad
by Theodor Richters, of Breslau, Germany.
The method hitherto used for the manufacture of nitrogenous manure in the
shape of a powder from nitrogenous materials, such as waste horn, leather, old
shoes, wool, hair, feathers, felt, fur, requires complicated and expensive heating
apparatus owing to the application of high pressure steam or superheated steam;
and the use of closed vessels for this purpose renders this process rather
dangerous.
Another disadvantage of the old method consists in the impossibility of
obtaining a perfectly dry product capable of being ground into powder, in conse-
quence of the simultaneous use of aqueous vapors and sulphuric acid, which causes
the production of compounds that attract moisture from the air.
It has been found that this wet heat reaching up to 400° Centigrade, may be
replaced by a moderate dry heat such as is used in an ordinary drying-room or
baker's oven, for destroying the structure of the waste materials.
By the action of a moderate dry heat on the leather waste impregnated with
sulphuric acid, as described above the process is much simplified and the object of
obtaining from the waste a dry product capable of being ground into powder, is
completely attained, the burning of the waste materials in presence of oxygen
which frequently occurred with the high temperatures hitherto employed being at
the same time avoided. Consequently the new process is carried out without waste
of material.
The new process is carried out in two stages the common feature of which is
the application of a moderate dry heat with tho access of air. The first stago

page_text: consists in heating the waste materials impregnated with diluted sulphuric acid, to
a temperature of 100° Centigrade in an ordinary drying room, thereby the
sulphuric acid is concentrated and the materials dried. The second stage consists
in further heating the dry waste materials impregnated with concentrated sulphuric
acid, to a temperature not exceeding 250° Centigrade with the access of air,
whereby their structure is completely destroyed. In practice the process is carried
out as follows: various kinds of nitrogenous matters, such as horn, leather, parts
of old shoes,. wool, hair, feathers, felt, waste furs, are placed in a bath of dilute
sulphuric acid. The strength of the acid depends on the nature and capillarity
of the raw material and varies between 1 and 15° Baumé.
Subsequently the raw materials impregnated with diluted sulphuric acid are
dried with the access of air, at a temperature less than 100° Centigrade whereby
the acid contained in the material is concentrated. Ovens for drying chicory or
beet root have been found very suitable for the purpose.
The dried and impregnated raw material is then placed in a room heated to a
temperature not exceeding 250° Centigrade for which purpose periodically or
continuously working baking ovens are suitable.
The time during which the material is left in the oven varies between one and
four hours and depends on the nature of the material. The combined action of
high temperature and concentrated sulphuric acid decomposes and alters the
structure of the material, thereby rendering the latter capable of being easily
disintegrated and ground into a fine powder after cooling.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Herbert John Haddan in the Great Seal Patent Office on the
19th December 1882.
HERBERT JOHN HADDAN, of Kensington, Middlesex
"IMPROVEMENTS IN
THE MANUFACTURE OF ARTIFICIAL MANURE a communication to me from
abroad by Theodor Richters, of Breslau, Germany
The method hitherto used for the manufacture of nitrogenous manure in the
shape of a powder from nitrogenous materials, such as waste horn, leather, old
shoes, wool, hair, feathers, felt, fur, requires complicated and expensive heating
apparatus owing to the application of high pressure steam or superheated steam;
and the use of closed vessels for this purpose renders this process rather
dangerous.
Another disadvantage of the old method consists in the impossibility of obtaining
a perfectly dry product capable of being ground into powder, in consequence of the
.combined action of aqueous vapors and sulphuric acid, which causes the production
of compounds that attract moisture from the air.
It has been found that this wet heat reaching up to 400° Centigrade, may be
replaced by a moderate dry heat such as is used in an ordinary drying room or
baker's oven, for destroying the structure of the waste materials.
By the action of a moderate dry heat on the leather waste impregnated with
sulphuric acid, as described above the process is much simplified and the object of
obtaining from the waste a dry product capable of being ground into powder, is
completely attained, the burning of the waste inaterials in presence of oxygen
which frequently occured with the high temperatures hitherto employed being at
the same time avoided. Consequently the new process is carried out without
waste of material.
The new process is carried out in two stages the common feature of which is
the application of a moderate dry heat with the access of air.
The first stage consists in heating the waste materials impregnated with diluted
sulphuric acid to a temperature of 100° Centigrade in an ordinary drying room,
whereby the sulphuric acid is concentrated and the materials are partly dried.
The second stage consists in further heating the dry waste materials impregnated
with concentrated sulphuric acid, to a temperature not exceeding 250° Centigrade
with the access of air, whereby their structure is completely destroyed. In practice
the process is carried out as follows: various kinds of nitrogenous matters, such
as horn, leather, parts of old shoes, wool, hair, feathers, felt, waste furs, are placed
in a bath of dilute sulphuric acid. The strength of the acid depends on the
nature and capillarity of the raw material and varies between 1 and 15° Baumé.
Subsequently the raw materials impregnated with diluted sulphuric acid are
dried with the access of air, at a temperature not exceeding 100° Centigrade whereby
the acid contained in the material is concentrated. Ovens for drying chicory or
beet root have been found very suitable for this purpose.
The dried and impregnated raw material is then placed in a room heated to a
temperature not exceeding 250° Centigrade, for which purpose periodically or
continuouly working baking ovens are suitable.
The time during which the material is left in the oven varies between one and
four hours and depends on the nature of the material. The combined action of
high temperature and concentrated sulphuric acid decomposes and alters the
structure of the material, thereby rendering the latter capable of being easily
disintegrated and ground into a fine powder after cooling.

page_text: ULATAL.
In the process of producing nitrogenous manure from nitrogenous material: The
moderate dry heating of waste material impregnated with sulphuric acid in two
stages and with the access of air in such a manner that the sulphuric acid is first
concentrated and the waste material partly dried by heating the said material up 5
to 100 degrees Centigrade and that the said waste material is further dried and
its structure destroyed by a subsequent heating up to 250 degrees (maximum), and
so as to prevent the burning of the material by keeping the temperature low.
The whole substantially as described.
In witness whereof I the said Herbert John Haddan have hereunto set my 1
hand and seal this nineteenth day of December A.D. 1882,