IMPROVEMENTS IN OBTAINING AMMONIA IN THE CARBONIZATION OF ANIMAL BONES AND OTHER NITROGENOUS SUBSTANCES, AND IN APPARATUS THEREFOR.
Year: 1880

page_text: LETTERS PATENT to Carl Kesseler, of 63, Mohrenstrasse, Berlin, W., in the.
Empire of Germany, Civil Engineer and Patent Solicitor, for an Invention
of "IMPROVEMENTS IN OBTAINING AMMONIA IN THE CARBONIZATION OF
ANIMAL BONES AND OTHER NITROGENOUS SUBSTANCES, AND IN APPARATUS
THEREFOR. A communication from Hans Peter Loronzen, of Friedrichstadt,
in Schleswig, in the Empire of Germany.
PROVISIONAL SPECIFICATION left by the said Carl Kesseler at the Office
of the Commissioners of Patents on the 31st January 1880.
CARL KESSELER, of 63, Mohrenstrasse, Berlin, W., in the Empire of Germany,
Civil Engineer and Patent Solicitor. "IMPROVEMENTS IN OBTAINING AMMONIA
IN THE CARBONIZATION OF ANIMAL BONES AND OTHER NITROGENOUS SUBSTANCES,
AND IN APPARATUS THEREFOR." (A communication from Hans Peter Lorenzen, of
Friedrichstadt, in Schleswig, in the Empire of Germany.)
According to this Invention the bones or pieces of bone are carbonized in the
ordinary pots and furnaces with suitably regulated air draught. The smoke pro-
duced in the heating of the furnace passes off into a chimney by a direct flue; as
soon as gases are evolved from the bones by the heat the direct communication
with the chimney is closed by a damper, and the products of combustion and dis-
tillation are by opening of another damper allowed to pass over a layer of glowing
burnt lime, or at the beginning of the carbonization process they may be led to a
small furnace, on the hearth of which there is a layer of the oxide of calcium; the
walls of this furnace may be lined with large pieces of burnt lime in order to afford
as large a surface of contact for the gases with the burnt lime as possible. The tar
and lighting gas carried along with the gases are burnt in this furnace; the oxide
of calcium when glowing hot has the property of favourably acting on the
separation of the gases, so that the nitrogenous substances easier develop into
ammonia.
The gases so treated then ascend into an iron vessel having an upright diametrical
partition to compel the gas to ascend and then to descend so as to be exposed to as
large a cooling surface as possible. Carbonate of ammonia deposits on the walls
of this vessel, and may be removed by manholes.

page_text: Having passed the cooling apparatus the gases come to a tower or upright vessel
lined with lead, and charged with coke; on the top of this vessel is placed a pan
containing sulphuric acid, which is allowed to trickle down by small pipes to meet
the ascending gases. The pieces of coke in the tower serve to distribute the
sulphuric acid over the whole interior of same, while slowly descending and
mixing with the ammonia contained in the gases arrived below the fluid is caught
again and again, and used until sufficiently saturated with ammonia.
The gases pass from the upper part of this tower to the lower part of a similar
tower by a descending pipe in order to bind any still remaining ammonia in a
similar manner by means of sulphuric acid.
As long as the sulphuric acid in the first tower is tolerably fresh it takes up all
the ammonia, and the second tower is then not used, but when the sulphuric acid
becomes less receptible the second tower is taken into use or put in position. For
this purpose there is also a direct flue leading from the first tower to the chimney;
this flue can be closed by a lead damper; the gases may thus be compelled either
to go direct to the chimney, or else by the descending pipe up through the interior
of the second tower, first traversing the whole height of same, and then to the
chimney.
In this manner the greatest part of the nitrogen contained in the bones or other
nitrogenous substances is obtained in the form of ammonia without any injury to
the quality of the animal charcoal; these two objects have not heretofore been
obtained at the same time.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Carl Kesseler in the Great Seal Patent Office on the 31st July
1880.
CARL KESSELER, of 63, Mohrenstrasse, Berlin, W., in the Empire of Germany,
Civil Engineer and Patent Solicitor. "IMPROVEMENTS IN OBTAINING AMMONIA
IN THE CARBONIZATION OF ANIMAL BONES AND OTHER NITROGENOUS SUBSTANCES,
AND IN APPARATUS THEREFOR." (A communication from Hans Peter Lorenzen, of
Friedrichstadt, in Schleswig, in the Empire of Germany.)
The carbonization of animal bones for sugar refining has heretofore been done by
burning the broken or ground bones in cast iron pots in a furnace made of bricks
like the furnace A shown in the accompanying Drawing, which serves to illustrate
this present Invention. According to another but now rarely used process the
broken or ground bones are carbonized in closed retorts, whereby a partial yield of
ammonia is obtained as the evolved gases pass through closed vessels charged with
water or sulphuric acid, according as carbonate or sulphate of ammonia is to be
obtained. This method has, however, now been generally abandoned for the special
purpose of carbonization of bones, because the charcoal obtained is of a less value,
which the gain of ammonia does not compensate for. The deterioration in quality
of the charcoal is chiefly owing to the fact that the gases cannot freely escape from
the retorts, whereby a part of the tar produced is burnt in the charcoal, stopping
up the fine pores of same, so that the charcoal loses in value not only for its appli-
cation in sugar refineries but also loses in appearance for the market.
And in order that this Invention may be fully understood I will describe
the same with reference to the accompanying Drawings, in which Figure 1 is a
plan section, Figure 2 a vertical longitudinal section, and Figure 3 a part end
view of the apparatus used therein.
According to this Invention the bones or pieces of bone are carbonized in the
ordinary pots and furnaces A, with suitably regulated air draught. The smoke
produced in the heating of the furnace passes off into a chimney S by a direct
flue C; as soon as gases are evolved from the bones by the heat the direct commu-
nication with the chimney is closed by a damper S', and the products of combustion
and distillation are, by opening of another damper S², allowed to pass over a layer
of glowing burnt lime, or at the beginning of the carbonization process they may
be led to a small furnace F, on the hearth of which there is a layer of the oxide of
calcium; the walls of this furnace may be lined with large pieces of burnt lime in
order to afford as large a surface of contact for the gases with the burnt lime as
possible. The tar and lighting gas carried along with the gases are burnt in this
furnace; the oxide of calcium when glowing hot has the property of favourably
acting on the separation of the gases, so that the nitrogenous substances easier
develope into ammonia.
The gases so treated then ascend by the slanting flue C¹ into an iron vessel B
having an upright diametrical partition to compel the gases to ascend and then to
descend so as to be exposed to as large a cooling surface as possible. Carbonate of
ammonia deposits on the walls of this vessel, and may be removed by man-
holes m, m.
Having passed the cooling apparatus the gases come to a tower T or upright
vessel lined with lead, and charged with cokes; on the top of this vessel is placed a
pan containing an acid, by preference sulphuric acid, of about 50 to 52° Beaumé,
which is allowed to trickle down by small pipes to meet the ascending gases. The
pieces of coke in the tower serve to distribute the sulphuric or other acid over the
whole interior of same, while slowly descending and mixing with the ammonia
contained in the gases; or, instead of an acid, common water may be made to
trickle down through the tower for absorbing the ammonia. On arrival below the

page_text: fluid is caught again and again, and used until sufficiently saturated with ammonia.
The gases pass from the upper part of this tower to the lower part of a similar
tower T¹ by a descending pipe R in order to bind any still remaining ammonia in
a similar manner by means of sulphuric acid.
As long as the sulphuric acid in the first tower T is tolerably fresh it takes up
all the ammonia, and the second tower is then not used; but when the sulphuric
acid becomes less receptible the second tower is taken into use or put in position.
For this purpose there is also a direct flue leading from the first tower T to the
chimney; this flue can be closed by a lead damper, and may go straight through
the second tower T', as shown in dotted lines; the gases may then be compelled
either to go directly to the chimney, or else by the descending pipe R up through
the interior of the second tower, first traversing the whole height of same, and then
to the chimney. These damper appliances are not shown in the Drawing, and may
be arranged in many different ways.
In this manner the greatest part of the nitrogen contained in the bones or other
nitrogenous substances is obtained in the form of ammonia without any injury to
the quality of the animal charcoal; these two objects have not heretofore been
obtained at the same time.
And having thus described and ascertained the nature of this Invention, and the
mode in which it is or may be carried into effect, I declare that I do not claim any
of the apparatus described separately, but I claim as the Invention communicated
to me,-
First. Obtaining ammonia by the carbonization of animal bones and other
nitrogenous substances by conducting the gases of combustion and distillation
through a furnace containing oxide of calcium, then passing them through cooling
apparatus, and then absorbing their ammonia by means of sulphuric or other acid
or water in towers charged with cokes, substantially as and for the purpose set
forth.
Second. The combination of a carbonization furnace, a furnace containing calcium
oxide, a cooling apparatus, one or two towers for absorbing the ammonia in animal
bones or other nitrogenous substances, a chimney, or other draught producing
appliance, and a flue which serves to connect the latter with the calcium oxide
containing furnace in the preliminary heating of the apparatus, substantially as and
for the purpose described, and also specially as shown in the Drawings.
In witness whereof, I, the said Carl Kesseler, have hereunto set my hand and
seal, this Twenty fourth day of July, in the year of our Lord One thousand
eight hundred and eighty.