IMPROVEMENTS IN BONE BOILING, AND IN APPARATUS THEREFOR
Year: 1881

page_text: LETTERS PATENT to Gerard Wenzeslaus von Nawrocki, Proprietor of the
Firm of J. Brandt & G. W. v. Nawrocki, Patent Solicitor and Civil Engineer,
of 124, Leipzigerstrasse, Berlin, Germany, for an Invention of "IMPROVEMENTS
IN BONE BOILING, AND IN APPARATUS THEREFOR." A communication from
Alfred Leuner, of Landshut, in Bavaria.
PROVISIONAL SPECIFICATION left by the said Gerard Wenzeslaus von
Nawrocki at the Office of the Commissioners of Patents on the 8th September
1881.
GERARD WENZESLAUS VON NAWROCKI, Proprietor of the Firm of J. Brandt
& G. W. v. Nawrocki, Patent Solicitor and Civil Engineer, of 124, Leipziger-
strasse, Berlin, Germany. "IMPROVEMENTS IN BONE BOILING, AND IN APPARATUS
THEREFOR." (A communication from Alfred Leuner, of Landshut, in Bavaria.)
According to this present Invention bones are effectually deprived of all their greasy
parts by means of low pressure vapour or steam from the known fat solvents, hereby
the dangers of producing stupefaction and explosion inherent in the high pressure
steam process now employed are avoided. This present process offers also the
advantage that it is closely akin to the practice heretofore used in the steaming of
bones and the depriving them of their gluey parts.
An essential feature of this Invention is that a preliminary steaming by means
of water steam is employed previously to the removal of the fat, and by this
means the air is driven out of the pores of the bones and the fat rendered more
soluble. Furthermore, the bones are also during the removal of the fat while
exposed to the action of the solvent (such as benzine) in the form of steam, also
acted on by steam of water which materially assists the dissolving action of the
solvent steam.
The digester is provided with a perforated false bottom or grid, and is charged
with bones; water steam is let in by a pipe so as to drive the air out of the
digester and out of the pores of the bones, passing out by a cock; this latter is

page_text: then closed and the steam pressure heightened so as to soften the cells of the
bones, and to make the fat therein more soluble. When pressure has been retained
a suitable time it is entirely removed by closing the steam inlet cock and opening
the outlet cock. The condense water under the false bottom is drawn off by a
cock and used as heretofore.
A reservoir charged with water and benzine, or with another liquid evaporative
solvent for fat is used in connection with the digester; the water forms the lower
part of its contents and two pipes dip into it, one from a condenser pipe series and
the other from a connecting reservoir. The steam outlet cock and the condense
water cock on the digester are closed, the contents of the solvent reservoir are
then emptied into the digester, and the reservoir charged with the same quantity
of water. The lower water layer in the digester is now heated by steam admission,
and gives off its heat to the superincumbent layer of benzine, so that benzine gas
is developed, which by the connecting reservoir enter the condenser, condense
therein, and return to the collecting or connecting reservoir in a liquid form; when
it has risen therein to a certain height it flows off by a pipe and returns to the
digester, distributing itself over the bones by means of a deflector plate. The
water steam simultaneously arising takes part in this cycle action, thus aiding the
dissolving action. Vapours which are not quite condensed enter the reservoir
below the water level; this reservoir is in connection with the atmosphere through
a small condenser which condenses the gases that may yet remain and carries
them back to the reservoir.
When the water steam, the benzine steam, and the liquid benzine have thus
acted for a time on the bones in a continuous circulation, another series or set of
condensing pipes in the large condenser act as distilling apparatus. By opening
the cock on the pipe which terminates under the water in the reservoir, the con-
densed benzine is then admitted from the collecting reservoir to the reservoir for
the solvent. The condense pipes in the condenser act also on the vapours that
may collect in the collecting reservoir, and the small condenser on the reservoir
prevents the vapours from passing out into the workroom.
By continued boiling of the liquids in the digester all the benzine is driven out,
and it is regained in the reservoir. When nothing but water passes over, which is
observable through sight glasses inserted in the small condenser, the fat is entirely
removed.
The fat and water are drawn off by the outlet cock below; the fat is separated
from the glue forming liquid, and the bones have the vapours and glue removed in
the ordinary manner

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Gerard Wenzeslaus von Nawrocki in the Great Seal Patent Office on
the 8th March 1882.
GERARD WENZESLAUS VON NAWROCKI, Proprietor of the Firm of J. Brandt
& G. W. v. Nawrocki, Patent Solicitor and Civil Engineer, of 124, Leipziger-
strasse, Berlin, Germany. "IMPROVEMENTS IN BONE BOILING, AND IN APPARATUS
THEREFOR." (A communication from Alfred Leuner, of Landshut, in Bavaria.)
Until lately the fat has been removed from animal bones by means of water or
steam from water, and as the attempts at using benzine, sulphide of carbon, or
other chemicals for this purpose, as has been done in other trades in a liquid state,
or in the form of low pressure steam have not been successful, the use of these
means in the form of high pressure steam was resorted to. But such high pressure
steams are very dangerous, because large masses of same may suddenly flow out
even with the most regular working, and such vapours have a stupefying effect, and
moreover ignite by contact with fire even at a great distance.
According to this present Invention, bones are effectually deprived of all their
greasy parts by means of low pressure vapour or steam from the known fat
solvents, hereby the dangers of producing stupefaction and explosion inherent in
the high pressure steam process now employed are avoided. This present process
offers also the advantage that it is closely akin to the practice heretofore used in
the steaming of bones and the depriving them of their gluey parts.
An essential feature of this Invention is that a preliminary steaming by means
of water steam is employed previously to the removal of the fat, and by this means
the air is driven out of the pores of the bones and the fat rendered more soluble.
Furthermore, the bones are also during the removal of the fat while exposed to
the action of the solvent (such as benzine) in the form of steam also acted on by
steam of water which materially assists the dissolving action of the solvent
steam.
The accompanying Drawing is a part sectional elevation of an apparatus con-
structed according to this Invention.
The digester A is provided with a perforated false bottom or grid a and is
charged with bones; water steam is let in by a pipe h, so as to drive the air out of
the digester and out of the pores of the bones, passing out by a cock p; this
latter is then closed and the steam pressure heightened so as to soften the cells of
the bones and to make the fat therein more soluble. When pressure has been
retained a suitable time it is entirely removed by closing the steam inlet cock and
opening the outlet cock p. The condense water under the false bottom is drawn
off by a cock d and used as heretofore.
A reservoir B charged with water and benzine, or with another liquid evaporative
solvent for fat, is used in connection with the digester, the water forms the
lower part of its contents, and two pipes and n dip into it, one from a condenser
pipe series, and the other from a connecting reservoir C. The steam outlet cock p
and the condense water cock d on the digester A are closed, the cocks g and i are
opened, and communication opened between the condenser D and the connecting or
collecting reservoir C; by opening the cocks q and the contents of the solvent
reservoir are then emptied into the digester A These cocks are then shut and
the reservoir B charged with the same quantity of water. The lower water layer
in the digester A is now heated by steam admission and gives off its heat to the
superincumbent layer of benzine, so that benzine gas is developed, which by the
pipes and connecting reservoir C enter the condenser D, condense therein, and
return to the collecting or connecting reservoir Cin a liquid form, when it has.

page_text: risen therein to a certain height it flows off by the pipe 8 and returns to the
digester A, distributing itself over the bones by means of a deflector plate. The
water steam simultaneously arising takes part in this cycle action, thus aiding the
dissolving action. Vapours which are not quite condensed enter by the pipe into
the water in the reservoir B below the water level; this reservoir is in connection
with the atmosphere through a small condenser E which condenses the gases that
may yet remain and carries them back to the reservoir B.
When the water steam, the benzine steam, and the liquid benzine, have thus
acted for a time on the bones in a continuous circulation, the cock h is opened, the
cock g closed, and another series or set of condensing pipes shown in dotted lines
in the large condenser D act as distilling apparatus. By opening the cock K on the
pipe n which terminates under the water in the reservoir B, the condensed benzine
is then admitted from the collecting reservoir C to the reservoir B. The condense
pipes in the condenser. D act also on the vapours that may collect in the collecting
reservoir, and the small condenser E on the reservoir B prevents the vapours from
passing out into the workroom.
By continued boiling of the liquids in the digester A all the benzine is driven
out and it is regained in the reservoir B. When nothing but water passes over,
which is observable through sight glasses inserted in the small condenser, the fat is
entirely removed..
The fat and water are drawn off by the outlet cock d below; the fat is separated
from the glue forming liquid, and the bones have the vapours and glue removed
in the ordinary manner.
The application of water steam in this process has also the advantage that it
causes the commencement of the glue formation in the first part of the process,
that is, the working with steam under pressure, and continues and completes it
during the second part, that is, the working with steam of benzine and water under
ordinary atmospheric pressure. The new process thus not only admits of removal
of the fat, but also of obtaining a good undecomposed glue which has not hereto-
fore with the usual processes been the case. Lastly, the nitrogenous parts of the
bones are not decomposed by the high temperature, and the meal products contain
more nitrogen, are more fermentable, and hence again are more valuable for manure
purposes. The bone meal produced from the bones and forming the raw material
for the manufacture of animal charcoal for filtering purposes is not so apt to split
nor-so-gray-and-bad-in-appearance, but becomes-more-round-in-form-and-light-in
colour, and in burning it retains more carbon.
I claim as the Invention cominunicated to me,―
First. The removal of the fat from bones by means of vapours from liquid and
evaporative fat solvents under a pressure in equilibrium with the atmospheric
pressure heated by simultaneously co-acting hot watery vapours, the bones having
previously been treated by means of high pressure water steam for the purpose of
opening up the materials from which the fat is to be removed.
Second. In an apparatus for the removal of fat from bones, the combination of
the steam apparatus A with the reservoir B for the solvents, the cooling apparatus D,
and the collecting reservoir C, substantially as set forth.
In witness whereof,. I, the said Gerard Wenzeslaus von Nawrocki, have
hereunto set my hand and seal, this Fourth day of March, in the
year of our Lord One thousand eight hundred and eighty two.
-GERARD-WENZESLAUS VON NAWROCKI. (L.S.)