Improvements in Process and Apparatus for Extracting Glue or Gelatine and Grease out of Hide and Skin Waste and of Bones at comparatively Low Temperature.
Year: 1892

page_text: Date of Application, 18th Jan., 1892-Accepted, 20th Feb., 1892
COMPLETE SPECIFICATION.
Improvements in Process and Apparatus for Extracting Glue or
Gelatine and Grease out of Hide and Skin Waste and of Bones at
comparatively Low Temperature.
I, LOUIS BERTRAM of 10, Grünauer Strasse, Berlin, Kingdom of Prussia,
Germany, Manufacturer, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement :-
My invention relates to an improved method of extracting glue, or gelatine and
grease out of hide and skin waste, and of bones, and also to the apparatus made use
of in said improved method.
In order to obtain out of butcher's and tanner's waste, i.e. the so-called fleshings,
cuttings, scrapings, hide and skin pieces, bones, etc., hereinafter collectively called
"the raw material" the entire or nearly the entire quantity of glue or gelatine and
grease contained therein, and in order to obtain the glue pure and free from dirty
matter and to preserve its highest strength and tenacity, it is indispensable to carry
out the extraction as quickly as possible and to expose both the raw material and
the glue liquid constantly forming itself to a comparatively low temperature only.
I have ascertained by long and numerous experiments that on an average the
temperature best answering the above said requirements is 75 to 85° Celssius equal
to 167 to 185° Fahrenheit or about 15% below boiling point. 1 employ in my
process an apparatus constructed in a peculiar manner so as to enable the maker to
work on this improved principle and thereby increase its yield of glue and better its
quality. The apparatus may of course be made in various shapes, the one shown
in the drawing annexed hereto being however the preferred form. The better to
make my meaning clear, I will proceed to describe the process and the construction
of the apparatus as shown in the accompanying drawings, on which:
Fig. is a sectional elevation of the apparatus on line - of Fig. 2,
Fig. 2 is a plan of the same,
Fig. 3 is a cross-sectional elevation of the same on line y-y of Fig. 2,
Fig. 4 is a sectional elevation, corresponding to Fig. 1, of a modification.
Similar letters refer to similar parts throughout the several views.
The apparatus consists of an inner vessel or cistern A made of sheet iron, tinned
on the inner side, fitted a short distance above the bottom with a perforated
horizontal sieve plate B of sheet iron tinned and four vertical corner sieve plates C
likewise of sheet iron tinned. This inner vessel A, which is the extraction-room,
is surrounded by an outer mantle D made of sheet iron and the intermediate space
between inner vessel A and outer mantle D forms a hot water chamber E. Below
the bottom of this hot water chamber there is a third compartment F for the steam,
which is introduced by means of a straight perforated pipe or in any other
convenient manner.
In the inner vessel A I place 7 vertical hot water cylinders G made of sheet iron
tinned on the outer side. These cylinders are so disposed that there is an equal or
nearly equal distance between themselves as well as between the outer ones and the
sides of the inner vessel A, they emerge from the lower horizontal part of the hot
water chamber E, cut through the sieve plate B and tower above the top edges
of the inner vessel A, being either open at the top or closed in any convenient
manner.
On the bottom of the inner vessel A below the sieve-plate B I place a leaden
steam-pipe G with little holes for the purpose of boiling the "skutch" or residue
of the raw material at the end of the extracting operation. The apparatus is
further fitted in the usual way with steam-inlet valves H and H for direct steam, a

page_text: safety valve I giving way at a certain maximum pressure, a condensed steam water
ejector J, a water-gauge K for the water chamber E, an escape cock L. and an
inlet cock M both for the water in the water chamber E, 7 open connecting ends N
for the pipes, an escape cock O for the glue. liquid flowing off.
Instead of the
steam compartment F a steam.coil or serpentine pipe may be placed in the water
chamber E as shown in Fig. 4 and the water heated by such steam coil or pipe, but
I prefer the separate steam compartment. The water may also be heated in any
manner prior to its admission into the water-chamber E, and thus the heating
arrangement in the apparatus proper may be dispensed with.
I do not limit myself to the form of the specimen shown in the drawing. The
apparatus may also be constructed in a round or oval or any other shape that may
be convenient under special local circumstances. The bottom part may be curved
or bow bent as well as straight. Likewise the diemensions of the whole and the
parts and the measurements of the intermediate chambers as well as thicknesses of
the iron sheets may be varied according to the quantities and nature of the raw
material to be worked. It is however preferable that the height of the inner
vessel A and consequently the height of the raw material filled into same do not much
exceed 40 inches. The number of the vertical water cylinders & depends of course
on the size of the apparatus. In very small apparatus they may even be dispensed
with altogether, as in such case the heating surface of the hot water chamber E
may be sufficient to secure speedy extraction. The material of the apparatus or
parts of it may be not only iron, but also copper or any other metal that may be
found suitable. The vertical water cylinders G may also be made removable by
screwing them on at bottom or in any other manner.
The apparatus is used in this manner:
I
I fill the water chamber E with water up to the top of the sides and give a little
steam into steam compartment to warm the water up to about 150° F. In the
meantime I fill the inner vessel A with water to about one half its height and
charge it with the raw material, which has before been washed in the usual manner
and chemically treated, macerated or made tender according to its original degree of
toughness, distributing the material equally and loosely over the entire area.
then give full steam and keep the same up. The temperature of the water in the
water chamber E soon rises to near boiling point and remains there, and that of the
liquid in the inner vessel A to about 170 or 180° F. After about two hours a large
portion of the glue is formed and the water in vessel A being saturated with
same to about 12% this first glue solution is drawn off. Then I add fresh water
and proceed in the same way and if necessary repeat the same operation a third
time. Meanwhile the grease has been constantly rising to the surface and removed
in the usual manner. At last the residue or "skutch" containing, now but very
little glue and grease is covered with water and subjected to real boiling by giving
steam into the leaden coil G' and letting the same operate directly on the residue
through the little holes, whereby the last particles of glue and grease are liberated
and obtained. The residue itself is finally taken out and pressed into cakes in the
well-known manner or disposed of in the wet state as manure. The glue solutions
are either cooled and cut and dried directly (where thin clear glues are desired),
or, if it is intended to have thick, heavy glues like the so-called "Scotch," concen-
trated in a vacuum pan or other concentrating apparatus to about from 25 to 40%
and then further treated as usual.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what I
claim is :
1. The method of extracting glue, gelatine and grease from animal skin and.hide
waste and also from bones at a comparatively low temperature, consisting, in
subjecting the material to the heating action of an interposed. heated.. water-
chamber.
2. An apparatus for the extraction of glue, gelatine and grease from animal skin

page_text: and hide waste and also from bones at a comparatively low temperature, consisting
of a hot water chamber and of a chamber placed above the former, receiving the raw
material, for the purpose as described.
3. An apparatus for the extraction of glue, gelatine and grease from animal skin
and hide waste and also from bones at a comparatively low temperature, consisting
of a hot-water chamber having double side walls filled with heated water, and of a
chamber placed above the former, receiving the raw material, for the purpose as
described.
4. An apparatus for the extraction of glue, gelatine and grease from animal skin
and hide waste and also from bones at a comparatively low temperature, consisting
of a hot-water chamber and of a chamber placed above the former, receiving the
raw material, the water in the hot-water chamber being heated by means of a
serpentine pipe through which steam circulates, for the purpose as described.
5. An apparatus for the extraction of glue, gelatine and grease from animal skin
and hide waste and also from bones at a comparatively low temperature, consisting
of a hot-water chamber and of a chamber placed above the former, receiving the
raw material, the water in the hot-water chamber being heated by means of a
steam-chamber provided below the same, for the purpose as described.
6. An apparatus for the extraction of glue, gelatine and grease from animal skin
and hide waste and also from bones at a comparatively low temperature, consisting
of a hot-water chamber and of a chamber placed above the former, receiving the
raw material, the water in the hot-water chamber being heated either by means of
a steam-chamber provided below the same, or by a serpentine steam pipe placed
inside the same, the hot-water chamber in either case communicating with hot-water
tubes extending upwardly from the same and towering above the apparatus,
substantially and for the purpose as described.
Dated this 16th day of January 1805
By Robert Deissler,
LOUIS BERTRAM.
38, Alexander Strasse, Berlin, Germany, Agent for the Applicant.