IMPROVEMENTS IN TREATING SUBSTANCES, PRINCIPALLY ANIMAL MATTER, BY MEANS OF THE DIRECT INTRODUCTION OF SUPERHEATED STEAM, AS WELL AS IN THE APPARATUS EMPLOYED FOR THAT PURPOSE
Year: 1879

page_text: LETTERS PATENT to Henri Lissagaray, of No. 1, Rue Laffitte, Paris, France,
Chemist, for the Invention of "IMPROVEMENTS IN TREATING SUBSTANCES,
PRINCIPALLY ANIMAL MATTER, BY MEANS OF THE DIRECT INTRODUCTION OF
SUPERHEATED STEAM, AS WELL AS IN THE APPARATUS EMPLOYED FOR THAT
PURPOSE."
Sealed the 5th December 1879, and dated the 18th June 1879.
PROVISIONAL SPECIFICATION left by the said Henri Lissagaray at the
Office of the Commissioners of Patents on the 18th June 1879.
HENRI LISSAGARAY, of No. 1, Rue Laffitte, Paris, France, Chemist. " IMPROVE-
MENTS IN TREATING SUBSTANCES, PRINCIPALLY ANIMAL MATTER, BY MEANS OF THE
DIRECT INTRODUCTION OF SUPERHEATED STEAM, AS WELL AS IN THE APPARATUS
EMPLOYED FOR THAT PURPOSE."
This apparatus consists of a central cylindrical vessel surrounded by two
concentric cylinders, so as to leave two annular spaces enclosing the central vessel.
These annular spaces serve, the one adjacent to the central cylinder for the
admission of steain, and the exterior one for the reception of hot gases to superheat
the steam before it enters the central cylinder. A diaphragm divides the steain
jacket into an upper and lower half; the steam arrives through a suitably arranged
tube provided with a regulating cock in the upper half and becomes superheated by
coming in contact with the wall which separates the steam jacket from the hot
gases jacket, in which latter a current of gas heated to any desired degree is caused
to circulate by means of suitably arranged pipes. The steam thus superheated
enters the central cylinder through lateral holes formed near the top thereof, and
after passing through the substances contained in this cylinder leaves it through
lateral openings formed near the bottom, arriving in this manner in the lower half
of the stean jacket, where it again comes in contact with the wall between tho
steam and hot air jacket, so that when it leaves the lower half of the steam jacket
by a suitably arranged pipe it has still a sufficiently high degree of temperature to
prevent its condensation in the apparatus, whereby the latter might be clogged and
the operation seriously disturbed. Small holes formed in the bottom of the central

page_text: cylinder serve to let the liquid pass off into a suitable receptacle when matters are
treated which, by the influence of the heat, become liquid or partly liquid.
The hot air jacket is or may be surrounded with a layer of any suitable non-
conducting material in order to prevent loss of heat which would result from
radiation.
For the purpose of rendering the circulation of the hot air in its jacket more
active I arrange a steam tube terminating in a fine nozzle in the pipe through
which the hot air or gases are introduced, or in the pipe through which the air or
gases are drawn off. This steam nozzle, which serves in one case as injector, and in the
other case as ejector insures that the hot air jacket is always filled with fresh hot
air or gases, whilst those which have lost part of their heat by giving it off to the
wall, and thus superheating the steam introduced in the apparatus, are rapidly
drawn off through the pipe arranged for the purpose.
In order to facilitate the regulation of the apparatus in every respect I arrange a
steam gauge communicating with the central cylinder and three thermometers, one
being immersed in the central cylinder, another in the steam jacket, and the third
in the hot air jacket. The operation of the apparatus can be very nicely regulated
by observing these thermometers and the steain gauge, and by judiciously placing
the cocks which control the inlet and outlet pipes for hot air and steam.
This apparatus may be used for the treatment of various substances where a heat
has to be determined according to a certain curve of temperatures and pressures,
and more especially for melting tallow and for extracting fat from animal tissues,
with the peculiarity that the internal pressure can be such as not to exceed two
or three tenths of an atmosphere, even up to temperatures of 30 degrees centigrade
or more.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Henry Lissagaray in the Great Seal Patent Office on the 10th
December 1879.
HENRI LISSAGARAY, of No. 1, Rue Laffitte, Paris, France, Chemist. " IMPROVE-
MENTS IN TREATING SUBSTANCES, PRINCIPALLY ANIMAL MATTER, BY MEANS OF THE
DIRECT INTRODUCTION OF SUPERHEATED STEAM, AS WELL AS IN THE APPARATUS
EMPLOYED FOR THAT PURPOSE,"
These improvements relate to a process for treating animal substances, specially
suet and the refuse of meat, in such a way that the fatty matters are completely
separated from the nitrogenous. These latter being dried become, when crushed,
easily pulverulent. This powder is employed directly as a nitrogenous inanure.
This process may be applied in the same manner to refuse leather, horns, wool, and
feathers, all of which, in the same way as the refuse of meat, are converted entirely
into an assimilable manure.
In the apparatus I introduce directly,-
Firstly.. Saturated steam, which is there condensed so long as the temperature of
the apparatus, and the matters to be treated in it, is below 100 degrees centigrade.
Secondly. Saturated steam under a pressure not exceeding an effective atmo-
sphere when the above temperature has been reached.
Thirdly. Saturated steam which is instantly transformed into superheated steam,
and this by heat which it derives from the apparatus itself, for in this third period
the apparatus is heated by hot gases which are allowed to circulate in an exterior
jacket. The pressure of superheated steam must not exceed two tenths of an
atmosphere.
In the Drawings accompanying and forming part of this Specification the
apparatus presents the following peculiarities:-
Firstly. Superheating by a current of hot gases, and at a known temperature, of
a known weight of steam, which can be changed at will.
Secondly. Disposition of the superheating apparatus between the hot gases and
the substances to be treated which it surrounds in such a way that the loss of heat
is rendered sensibly nil.
Thirdly. Changing at will of the direction in which the superheated steam
circulates, so that its action on the matter to be treated is rendered uniforin.
Fourtly. Direction of the apparatus by means of simultaneous thermometrical
observations, allowing at every moment to ascertain the temperature of the
superheating apparatus, of the recipient, and of the jacket in which the hot gases
circulate.
In the Drawings, the like letters indicating like parts the apparatus as a type, is.
shewn as follows:-
S, space in which the substances to be treated are placed.
V, tube introducing saturated steam.
7, upper jacket in which the steam is superheated.
I, holes by which the superheated steam is introduced.
J, holes by which the steam and vaporised water go out.
V", lower jacket of steam.
V., tube by which the steam goes out.
G, jacket of hot gases.
C, non conducting substance.
F, bottom with obturator.
a, holes made in the obturator.
b, outlet for the steam condensed at the beginning of the operation.
M, division between the jacket of steam.
R, tube to fix pressure gauge to.
T, thermometer placed in the substances to be treated.

page_text: P, outlet pipe.
B, wood casing.
E, steam jet to cause a draught.
O, hole through which the steam passes.
The current circulating in the direction of the arrow by means of a draught in
the outlet chimney arrives from a furnace or other heater where the combustion is
complete without an excess of air. It follows from this that this gaseous matter,
composed exclusively of a mixture of carbonic acid and of steam and nitrogen,
cannot, notwithstanding the raising of the temperature, oxydise the metallic sides
of the apparatus, but other conditions of heated air or gases may be used.
O, supply of steam helping the draught, increasing the conductibility of the
gaseous matter, and allowing the temperature to be raised or lowered by being
itself varied.
V, tube supplying saturated steam, which may, if desired, be provided with a
variable diaphragm allowing of different supplies.
1
V2, outlet pipe for saturated steam after it has acted upon the substances to be
treated. This pipe is provided, as the tube V₁, with a variable diaphragm, so that
the different rates of proportion between these diaphragms allow different counter
pressures to be obtained.
V₁, jacket in which the saturated steam circulates between two sides of sheet
iron, one of these through which it is superheated divides it from the hot gases, the
other forms part of the recipient S.
S, recipient communicating by the holes I, I, I, with jacket V₁, and by the
holes J, J, J, with the jacket V" The first quantity of heat furnished by the hot
gases to the matters ejected from the jacket V₁ prevents any condensation till they
leave the apparatus.
R, pipe to which is attached a pressure gauge with a graduated scale.
a, a, a, holes through which the substances treated can flow when it is intended
to render them liquid by the process.
The disposition of this apparatus allows of the introduction of variations "ad
libitum."
Firstly. In the mass of hot gases circulating in the outer jacket, and this on
account of the variations in the weight of fuel burnt in a given time by the furnace
or other heater, and also by the variations in the depressions which cause the
circulation of the hot gases.
Secondly. In the temperature of these hot gases, and this on account of the
variations of the weight of steain introduced per second.
Thirdly. In the weight of saturated steam introduced in a given time into the
jacket V, and this on account of the variations in the holes of the diaphragm
which commands the inlet of the supply pipe V, the pressure in the boiler remaining
constant.
Fourthly. In the counter pressure existing in the receiver and the second
envelope, and this on account of the variations introduced in the proportions of the
diaphragms, the inlet and outlet supply pipes.
It follows froin these instantaneous variations,-
Firstly. In the mass and in the temperature of the hot gases.
Secondly. In the mass and in the temperature of the saturated steam introduced,
and therefore in the temperature and pressure of the superheat which this steam
acquires in the apparatus, that the substances placed in the receiver S can there be
heated by being subjected successively to pressures and temperatures in a deter-
mined order. It will therefore be possible to follow during the course of the
operation two diagrams traced before hand.
Firstly. A diagram of pressures.
Secondly. A diagram of temperatures.
Instead of using variable diaphragms, as above described, the admission of steam

page_text: into the apparatus, as well as its departure from it, may be better varied at will
by placing a conical cock or valve both at the inlet and outlet pipes V, and V,
respectively.
The suet, without being dried, as is customary in some other processes, is
chopped into as small pieces as possible and placed in the apparatus, which is then
closed.
Firstly. The apparatus being quite cold (for the hot gases are not then allowed
to circulate in the outer jacket) saturated steam is introduced into it and imme-
diately condensed. In proportion as it condenses the temperature rises gradually
to 100 degrees centigrade.
It is of importance to observe that at this period of the operation the pressure in
the apparatus is below atmospheric pressure.
If we call P, the weight of condensed water, we find that P is the sum of two
other weights (p + p p is the weight of water which is condensed by the
influence of the apparatus which absorbs caloric till its temperature is raised to
100 degrees centigrade; p is the weight of water condensed by the suet, which
absorbs caloric firstly to begin to inelt, and secondly, to be heated up to 100 degrees
centigrade. In this total (p + p') P, p can be rendered variable, for the
cooling influence of the apparatus can be made variable by the differences in the
exterior heating, which may be produced by means of hot gases circulating in
the exterior jacket. In practice this weight P may vary from 10% to 20% of
the weight of the substances treated. In this period of the operation only the
inlet cock for steam is opened, the outlet cock remaining closed.
=
Secondly. When the interior temperature has risen to 100 degrees centigrade all
the water condensed up to this point is drawn off, and with it such portion of the
tallow as is already melted.
By a new admission of steam the pressure is raised to one effective atmosphere,
and so maintained for 15 to 30 minutes.
During this period the steam must remain saturated and the exterior heating
must be such as only to prevent the loss of the interior caloric; in order to verify
this the therinometer indicating the temperature and the manometer indicating the
pressure in the exterior of the recipient should be carefully observed. Both these
indications must simultaneously agree with the "Index of corresponding pressures
and temperatures in saturated steain" as determined by Regnault. This remark is
very important, as saturated steam determines the formation of gelatine at the cost
of the membranes which contain the tallow and helps the separation of the latter.
At the end of the second period the mixture of tallow, gelatine, and water is run
off and added to the mixture of tallow and water already drawn out at the end of
the first period.
Thirdly. The admission of saturated steam is nen regulated so that its pressure
is about 10 (two tenths) of an atmosphere; then the temperature is raised by
exterior superheating, which is derived from increasing the temperature and the
circulation of the hot gases in the outer jacket. But whatever y be the raising
of the interior temperature when the steam is superheated f pressure must be
reduced exactly to the above determined value, or if superior, ust not exceed four
tenths of an atmosphere; this result is empirically obtained by
regulation of the inlet and outlet steam cocks. The temperatu __ ust be raised
slowly during an hour and a half from 100 to 120 degrees centi.ade, beyond which
it must not go.
2
.responding
It has been explained by the above description and accompanying Drawings that
the superheating of the steam in the interior recipient depends upon the heat
derived from the outer jacket, hence it may be concluded that the superheating of
the steam will be regulated and directed by the regulation and direction of the

page_text: The refuse of meat may be considered as suct, in which tallow has a minimum
weight and nitrogenous matter a maximum weight.
Its treatment is identical to that described above for suet.
When large quantities are treated at a time and consequently in large apparatus
the metallic weight of which is minimum in proportion to the weight of matter
treated, the weight of water p condensed by the mass of the apparatus is in
proportion much less than in a small apparatus. In the latter the value of pis
always sufficient to completely wash the substances treated (but it is important to
let out by degrees the condensed water). It is quite true that in a large apparatus
as the weight of refuse meat contained increases rapidly, the value of p¹ must
increase in the same proportion, but the filtering of this water is delayed by a
greater mass of organic matter, through which it has to pass. The treatment might
become very dangerous if some parts of the refuse neat treated contained any
ammonia already formed. This ought to be so much more borne in mind, as the
circumstances under which this gas is sometimes suddenly developed in the midst
of organic substances placed in contact with water are up to the present time
totally unknown.
Not only may the ammonia already formed be suddenly developed but it becomes
principally dangerous because it dissolves a part of the nitrogenous matters in
water, and it is principally from these dissolved matters that the ammonia therein
contained may be suddenly and violently discharged, as terrible accidents have
recently proved in France.
Therefore this treatment of refuse meat requires great care, and if a large mass
of suspected refuse have to be treated it should be previously washed in a stream

page_text: TREATMENT OF LEATHER.
The apparatus having been filled with refuse leather or old shoes hot gases are
allowed to circulate in the outer jacket in such a way that the weight p shall be
minimum. The saturated steam is then introduced into the apparatus for such a
length of time that the weight p¹ condensed by the refuse leather shall be equal
only to from 10% to 15% of its weight. This length of time is practically
determined by experience.
The inlet steam pipe is then closed and the heating is continued; by means of the
exterior jacket till the interior temperature is raised to 100 degrees centigrade. A
current of saturated steam is then admitted in such proportions that it may be
immediately superheated in the interior steam jacket before it arrives in contact
with the refuse leather, and this steam is immediately discharged by the outlet
steam pipe. This interior circulation being thus established the exterior circulation
of hot gases is so regulated that the superheated steam may in two hours be
brought to 120 or 130 degrees centigrade. The apparatus is then opened and the
leather taken out. Its consistence is soft and it has become elastic, but when
cooled it hardens and becomes at the same time friable and pulverulent. By
crushing it is then converted into a fine powder which, like the residue from the
tallow or meat, is of great value for manure.
It should be observed that during the first period the outlet pipe at the bottom
of the recipient should be left opened and no warm water remain in the bottom
when the temperature is raised to above 100 degrees centigrade, for the leather
will dissolve in warm water, and ammonia might be easily discharged from such a
solution.
In no case should saturated steam under pressure be admitted into the recipient;
the superheated steam must always be kept at the maximum limit of two tenths of an
atmosphere, and the free circulation from the inlet to the outlet steam pipes should
be carefully watched; besides, this circulation should be frequently inverted, in
order that the temperature may be kept equal in all the mass.
Horns, wool, and feathers are treated in the same manner as the refuse of,
leather.
Having now described and particularly ascertained the nature of the said
Invention and the mauner in which the same is carried into effect, I would
observe in conclusion that what I consider to be novel and original, and therefore
claim as the Invention secured to me by the hereinbefore in part recited Letters
Patent is,
First. The apparatus above described, and principally the arrangement of said
apparatus by which saturated steam can be immediately superheated, as well as the
arrangement by which such a superheating may be regulated, maintained, increased,
or decreased at will.
Second. The arrangement by which the said superheated steam may at the same
time operate on the substances to be treated by heating them, and recover that loss
of caloric from the hot gases in the outer jacket in such a way that the caloric so
recovered may be not only equal but superior to the caloric lost, so that the interior
temperature of the substances treated may be raised and simultaneously the super-
heating of the steam may be increased.
Third. The arrangement by which the superheated steam is produced under a
low pressure and the important peculiarity that by means of instantaneous
variations in the opening of the two conical taps or valves introduced in the inlet
and outlet steam pipes, low pressure, when superheating increases, may be maintained
or lessened at will.

page_text: Fourth. The treatment for extracting tallow from suet, the refuse of meat by the
successive use of condensed saturated and superheated steam in the manner sub-
stantially as described.
In witness whereof, I, the said Henri Lissagaray, have hereunto set my hand
and seal, this Tenth day of December, in the year of our Lord One thousand
eight hundred and seventy nine.
HENRI LISSAGARAY. (L.S.)