AN IMPROVED METHOD OF AND APPARATUS FOR RENDERING FATTY SUBSTANCES AND ANIMAL MATTER
Year: 1874

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine,
Lake, & Co., Patent Agents, Southampton Buildings, London, for
the Invention of "AN IMPROVED METHOD OF AND APPARATUS FOR
RENDERING FATTY SUBSTANCES AND ANIMAL MATTER."-A communication
from abroad by Henry S. Firman, of the City and State of New
York, United States of America.
PROVISIONAL SPECIFICATION left by the said William Robert Lake
at the Office of the Commissioners of Patents, with his Petition, on
the 9th July 1874.
I, WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co.,
Patent Agents, Southampton Buildings, London, do hereby declare the
nature of the said Invention for "AN IMPROVED METHOD OF AND APPARATUS
FOR RENDERING FATTY SUBSTANCES AND ANIMAL MATTER," a communication, to
be as follows:
1
The said Invention relates to a method of and apparatus for rendering
fatty substances and 'animal matter, which apparatus is adapted by

page_text: means of the peculiar construction, combination, and arrangement of its
parts to employ advantageously steam and hot air in combination with.
each other, that is to say, the main feature of the said Invention is the
employment of steam and hot air in combination and produced by
independent means, so that one can be regulated without affecting the
other.
In practising the said Invention I use a steam-tight cylinder, digester,
or tank made of boiler iron, either with an interior wall to form a jacket
tank, or without it, like the ordinary so-called "Wilson tank," as may
be preferred. A filling hole is suitably located at the top of the digester,
and a discharging hole at the bottom, and cocks are provided for
drawing off the melted fat and water, and for drawing off the water
accumulating from the condensation of the steam in the jacket. I
provide a pipe, by means of which steam is admitted from any suitable
boiler into the jacket when the interior wall is employed, and directly
into the digestor when the interior wall is not used.
A drum or cylinder is preferably located at about the centre of the
digestor, and a pipe provided with a suitable regulating cock affords the
means whereby communication is made with the hot-air chamber of the
furnace, and the drum thus supplied with heated air.
The furnace is constructed in the usual manner with ash-pit, grate
bars, and flues, but is provided with a heating chamber made of suitable
material and of proper form, which covers the entire fire. space of the
furnace, with the exception of a passage in front of the air flue. A
thermometer projects through the top of the drum, by means of which
the temperature within may be ascertained by external observation.
A pipe communicates at one end with the entrance of the digestor
near its top, and at the other with the aforesaid furnace by means of a
delivery pipe or retort having perforations, the intermediate: portion of
the pipe being formed into a coil, and inclosed within a cylinder serving
as à condenser. By means of this arrangement of parts the foul gases
evolved during the process of rendering are taken from the digester, and
after being conducted through the condenser, in which a coil is immersed
in water, and in which a partial condensation is effected, are discharged
through a perforated pipe into the furnace, where they are consumed.
I employ a closed retort that serves as a gas retort, into which when
suitable material is being rendered the vapors are converted into

page_text: $1
plates which unite either the outer or inner edges of the cylinder or
both, as may be desired. This cylinder is suitably hung within the
main tank or digester, and is connected by the double pipe to the main
pipe communicating with the fire-box of the furnace at any suitable
point, or if desired to the fire-box of the boiler. A similar arrangement
of pipes conveys the heated air from the top of the cylinder to the
smoke stack.
2.1.
If desired, a strainer may be caused to surround either wholly or in
part the cylinder, the lower portion of which may communicate by
means of a suitable pipe with the strainer lying loosely upon the
discharging plate. A chamber is formed on the lower part of the main
tank by means of the strainer plates, and is provided with a draw-off
cock. A steam pipe opens into the interior of the main tank or digester,
and is connected to the boiler by a pipe. A branch pipe conveys steam
to the chamber between the walls of the tank. A hot-air pipe leads
from either the gas consuming or the boiler furnace into the jacket, and
is provided with a suitable cut-off valve or damper and a cold-air pipe
with a suitable cut-off or damper. A thermometer is placed in the
hot-air cylinder, its upper end projecting through the tank, and another
thermometer is placed in the hot-air pipe between the fire-box and the
tank or digester. Between the thermometer and the fire-box is located
a cold-air pipe having a suitable stop-cock, and also a cock for shutting
off the supply of hot air entirely when desired.
:
- 1
1
A curtain similar to that above described is placed in the rear of the
gas-burning device, a small intervening space being left between it and
the rear end of the fire-box.
If desired, the hot air may be taken from the fire-box of the boiler
instead of employing a separate furnace, and the central hot-air cylinder
may be divided more than once, or may be divided diagonally, or in any
other proper manner; or it may be formed, if desired, of a coil of pipe
suitably covered and protected by strainer plates.
}

page_text: SPECIFICATION filed in pursuance of the conditions of the Letters
Patent, by the said William Robert Lake in the Great Seal Patent
Office on the 6th February 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Ninth day of July, in the year of
our Lord One thousand eight hundred and seventy-four, in the thirty-
eighth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said William Robert Lake, Her special
licence that I, the said William Robert Lake, my executors, adminis-
trators, and assigns, or such others as I, the said William Robert Lake,
my executors, administrators, and assigns, should at any time agree with,
and no others, from time to time and at all times thereafter during the
term therein expressed, should and lawfully might make, use, exercise,
and vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "AN IMPROVED
METHOD OF AND APPARATUS FOR RENDERING FATTY SUBSTANCES AND ANIMAL
MATTER," a communication to me from abroad by Henry S. Firman, of
the City and State of New York, United States of America, upon
the condition (amongst others) that I, the said William Robert Lake,
my exccutors or administrators, by an instrument in writing under my,
or their, or one of their hands and seals, should particularly describe
and ascertain the nature of the said Invention, and in what manner
the same was to be performed, and cause the same to be filed in the
Great Seal Patent Office within seven calendar months next and imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said William Robert Lake, do hereby
declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement, reference being had to the accompanying
Drawings forming a part of this Specification:-
The said Invention relates to a method of and apparatus for rendering
fatty substances and animal matter, which apparatus is adapted by

page_text: means of the peculiar construction, combination, and arrangement of its
parts to employ advantageously steam and hot air in combination with
each other.
Figure 4 is a sectional elevation of the furnace.
Figure 5 is a horizontal sectional view of the digester or tank and hot
air cylinder forming part of this apparatus; and Figure 6 shews a
segment of the said tank drawn to an enlarged scale.
A, Figure 1; represents a steam-tight cylinder, digester, or tank made
of boiler iron, either with an interior wall to form a jacket tank, as
shown in the Drawing, or without it, like the ordinary so called "Wilson
tank," as may be preferred; B represents a filling hole suitably located
at the top of the digester; and C, a discharging hole suitably located at
the bottom; D, D, D, represent cocks for drawing off the melted fat and
water; and E, a cock for drawing off the water accumulating from the
condensation of the steam in the jacket; I represents a pipe, by means
of which steam is admitted from any suitable boiler into the jacket when
the interior wall is employed, and directly into the digester when the
interior wall is omitted.
}
J represents a drum or cylinder preferably located at about the centre.
of the digester; and K, a pipe provided with a suitable regulating cock,
by means of which communication is made with the hot-air chamber of
the furnace L, and the drum thus supplied with heated air.
The furnace L is constructed below in the usual manner with ash-pit,
grate bar, and flues, but above is provided with a heating chamber O
made of suitable material and of proper form, which covers the entire
fire-space of the furnace with the exception of the passage x in front of.
the air flue, M represents a thermometer projecting through the top of

page_text: the drum, as shewn, by means of which the temperature within may be
ascertained by external observation.
.
F represents a pipe communicating at one end with the entrance of
the digester near its top, and at the other with the aforesaid furnace L
by means of the delivery pipe or retort P, having perforations i, as
shown in Figure 1, the intermediate portion of the pipe being formed.
into a coil and enclosed within a cylinder G serving as a condenser. By
means of this arrangement of parts the foul gases evolved during the
process of rendering are taken from the digester, and after being
conducted through the condenser, in which a coil is immersed in
water, and. in which a partial condensation is effected, are discharged
through a perforated pipe P into the furnace where they are consumed.
be
P¹ represents a closed retort, that serves as a gas retort, into which
when suitable material is being rendered the vapors are converted into
illuminating gas, which may be collected for use in the chamber con-
nected with its discharge end, as shown. If necessary this gas may
given a higher illuminating power than it would otherwise possess by
combining with it in the retort a suitable proportion of tallow, grease,
scrap-wood, oil, or any material from which gas for illuminating or
heating purposes may be manufactured. In connection with the above.
I employ charcoal or its equivalent as a deodorizing agent, the same
being placed in the retort in suitable quantities.
Q, Q, represent a curtain located upon each side of the retort and
parallel with it, by means of which the gases issuing from the deodorizing
pipe are checked until entirely consumed.
R, Figure 1, and R³, Figure 2, represent a curtain or moulding
preferably semicircular in shape which is located at the front end of the
cylinder, as shown, and by means of which the flames and products of
combustion are checked, and caused to circulate around the under
surface of the heater before escaping either by the ordinary flues v, v,
or the air passage x.
I represents a fan blower or other equivalent device located between
the condenser G and furnace L, which is employed for the purpose of
facilitating the removal of vapors and gases from the digester, and to
force them into-the.discharging pipe to be consumed in the furnace.

page_text: S represents a pipe, by means of which communication is made
between the digester A and the pipe T opening into the fan case, this
construction of parts being employed for the purpose of creating a
circulation of air through the hot air drum, the air passing in through.
the pipe K from the hot-air chamber, and out through the pipe S again.
into the furnace..
"
Fresh air may be supplied to the heating chamber by means of the
fan blower, or it may be taken from the fire chamber of the furnace L
directly when the fire is in such condition as not to evolve smoke. In
this case the damper is left open, so that the heat passes through the
flue X into the chamber O.
U represents a pipe, connected at one end to the top of the chamber O
and at the other to the pipe T, by means of which hot air from
chamber O is mixed with the condensed gases from the condenser G for
the purpose of causing their perfect combustion.
W represents a discharge cock, by means of which the water of cons
densation is drawn off from the condenser G.
r represents a cock adapted to regulate the flow through a pipe con-
necting the hot-air drum with the chimney, by means of which the
air may be permitted to pass off when necessary for the purpose of
establishing an equilibrium in the hot-air drum.
.
The operation of my apparatus will be readily understood. The
digester is supplied with contents through the filling hole in the top.
Steam is admitted from the boiler (not shown) through the pipe I to the-
jacket if the interior wall is used, or to the interior of the digester if the
wall is omitted. Hot air from the heating chamber is admitted
through pipe K into the hot-air drum J, and a circulation is effected by
means of the pipes S and r. The foul gases are drawn off through
pipe F, and entirely consumed or utilized by being converted into
illuminating gas.
The main feature of my Invention is the employment of steam and
hot air in combination, and in having there two different kinds of heat
produced by independent means, so that one can be regulated without
affecting the other.
It will be observed from the foregoing description that the jacket or
tank is heated by means independent and distinct from those employed

page_text: to heat the drum J. It is essential in my rendering process that the
inside drum or chamber should be of such form and so arranged as to
enable the operator to secure at will either a high or low temperature,
as the case may require, without reference to the temperature or pressure
in the jacket or in the single tank when that is used, this result being
readily accomplished by adapting the hot-air drum to be regulated as to
its temperature independently of the jacket or tank as desired. Under
the plan or arrangement heretofore in use this result was impracticable,
if not impossible, for the reason that the drum or chamber was so
arranged and placed, and so connected with other parts of the apparatus,
(they merely passing through the digester from top to bottom or from
side to side,) that the temperature in the drum or flue could not be
materially different from that in the jacket of the steam apparatus, ´or
from that in the outside chamber or flue of the hot-air apparatus, there
not being in either case any special or independent means for regulating
the temperature in the said drum or flue. Another essential point in
my process is that this drum or chamber should be three or four times
larger at the bottom than at the top, and properly proportioned.
I am aware that both flues and drums have been heretofore used in
both steam and hot-air rendering apparatus, but these were in cases where
either hot air or steam was alone employed, and not as in my process in
combination. I do not claim a flue passing through a rendering
apparatus.
It will be observed also that the material treated is acted upon by
radiated heat from the inclosing steam jacket, which is employed in
connection with radiated heat from an internal hot-air chamber.
The employment of different kinds of heat in the manner described
produces new and valuable results, the tallow having the color, grain,
and keeping qualities of that obtained when hot air is used exclusively,
while the usual danger of burning is almost entirely avoided.
i
A modification of the above apparatus, adapted to produce more
perfect results, is shown in Figures 3, 4, 5, and 6, and will now be
described.
Its novelty consists mainly,-.

page_text: inira. In the employment of CIAT Stoves peowy szwzg
Fourth. In the employment of steam in combination with radiated
heat from the steam jacket and radiated heat from the hot-air chamber.
Fifth. In the employment of hot air instead of steam in the jacket
in combination either with hot air or with steam in the hot-air
chamber.
Sixth. In the employment of certain means for the more perfect
regulation of the temperature.
And, seventh. In certain details of construction which in connection
with the foregoing will be fully described herein-after.
A represents the main tank constructed or any proper size and pro-
vided with the double wall a, a, to form an interior steam-tight chamber,
as shown. This chamber does not extend entirely around the circum-
ference of the tank, but on one or more sides at proper points it is so
divided that an intervening space is formed between its ends, as
shown at x in Figure 6. This space is covered upon its inner side with
a suitable strainer plate a¹, as shown in Figures 5 and 6, and its outer
wall is provided with suitable openings communicating with the draw
off cocks a², as, a', and the like. This space may be arranged vertically,
diagonally, or in any other suitable manner. Through this space also
the hot-air pipe or pipes leading to the central hot-air cylinder are
extended.
B represents the central hot-air cylinder consisting of suitable metal
plates united to form two independent semi-cylindrical chambers b, b,
Figure 5, by means of strainer plates 6', 6', which unite either the outer
or inner edges of the cylinder or both, as may be desired. This cylinder
is suitably hung within the main tank or digester and is connected
by the double pipe 62, Figure 5, to the main pipe 63 communicating.
with the fire-box of the furnace at any suitable point, or if desired to
the fire-box of the boiler. A similar arrangement of pipes 6', b³,
conveys the heated air from the top of the cylinder to the smoke stack,
as shown.

page_text: which may communicate by means of a suitable pipe with the strainer D,
Figure 3, lying loosely upon the discharging plate E. F represents
a chamber formed on the lower part of the main tank by means of the
strainer plates and which is provided with the draw-off cock f, as shown;
G represents a steam pipe opening into the interior of the main tank or
digester which is connected to the boiler by the pipe g, as shown; g'
represents a branch pipe which conveys steam to the chamber between
the walls of the tank; G¹ represents a hot-air pipe of suitable dimensions
leading from either the gas consuming or the boiler furnace into the jacket,
and is provided with a suitable cut-off valve or damper 9² and cold-air
pipe 9³, with a suitable cut-off or damper; H represents a thermometer
the bulb of which is placed in the hot-air cylinder, its upper end pro-
jecting through the tank, as shown; H¹ represents a thermometer
placed in the hot-air pipe between the fire-box and the tank or digester.
Between the thermometer and the fire-box is located a cold-air pipe h
having a suitable stop-cock, and also a stop-cock h¹ adapted to shut-off
the supply of hot air entirely when desired.
1.11.
I, Figure 4, represents a curtain similar to that described in Figure 2,
which is placed in the rear of the gas burning device, a small inter-
vening space being left between it and the rear end of the fire-box.
The operation of my improved apparatus is substantially as follows:-
The fatty substances to be rendered are introduced into the digester
through the man-hole in the usual manner. Steam from the boiler is
introduced into the chamber between the walls of the tank, and hot-air
is introduced into the central cylinder.
If desired, steam may also be introduced directly into the material
under treatment through pipe G, and hot air may be introduced
directly into the jacket by means of the pipe G', or hot air and steam
at the same time, as will be readily seen. When sufficiently acted upon
or treated the melted fat is first drawn off through the proper stop-cocks
and then the water also from the lower cocks in the usual manner.
i
The temperature in the internal hot-air cylinder may always be
ascertained by inspecting the themometer placed therein, and it may
be readily regulated by adjusting the stop-cocks in the supply pipes.
If it is desired to cool the hot-air cylinder quickly at any time the
hot air may be entirely cut off, and cold air may be permitted to enter
:

page_text: It
through the pipe h. When the discharging door is opened the lower
loose strainer plate falls out with the 'contents of the digester.
must then be recovered and placed in position before the next batch is
treated.
Some of the advantages of the above described construction are as
follows: The combination of the tank with the intervening strainer space
between the ends of the steam chamber in the walls of the tank is
advantageous, because in consequence thereof the desired result, that is,
the straining of the liquid, is accomplished in a simple and economical
manner. Another and very great advantage in this respect is that it
leaves but a single wall to be pierced for pipes, and obviates the necessity
of expensive and troublesome packing, as would be required if the
chambers of the jacket were pierced. The construction of the. hot air
cylinder is advantageous, because by its employment the hot liquids are
permitted during the process of rendering to circulate freely throughout
the tank, and consequently the temperature of the entire mass is equalized
or nearly so. By the employment of the strainer about the central
cylinder described, the removal of the fluid contents is much facilitated,
as a chamber is formed between the strainer plate and the cylinder, in
which the fluid is free to settle without impediment. By means of the
loose strainer and the strainer chamber at the lower part of the tank
and the connecting pipes the fluid is caused to settle below the scrap,
and is readily removed through the draw-off cock. The employment of
steam in connection with the radiated heat from the jacket and the
radiated heat from the heated central cylinder is advantageous, because
by means of it the pressure and temperature in the tank or digester can
be more readily secured and controlled. It can also be employed for
the purpose of more rapidly heating the mass of material under treat-
ment in connection with the other described means for heating..
It having been proved by experience that steam admitted directly
to the material under treatment, as heretofore practised, is detri-
mental to the product, giving to the tallow a comparatively dull dead
color and a somewhat rancid odor, thus injuring its commercial value;
the steam should always be used very sparingly, and in the treatment of
some kinds of material, such for instance as hog's fat and some kinds of
animal refuse, I do not employ it at all, but depend entirely upon the
radiated heat from the steam jacket and hot air drum to accomplish the.
rendering, the result in such cases being always more satisfactory..

page_text: In the few cases where I employ the steam by admitting it directly
to the matter under treatment I merely use it to increase temporarily the
pressure in the digester by admitting it through a pipe of proper size
never exceeding from five to eight minutes at a time, and only once every
one or two hours intermittingly, so that in the time of treatment of a
batch of from seven to nine hours duration I would not employ the steam
altogether in this way more than twenty or thirty minutes, while the
radiated heat from the steam jacket and from the hot air drum is
employed constantly or without any intermission.
'
By the employment of hot air in the jacket instead of steam, or by :
the use of it alternately with steam or in connection with steam, it will
bee seen that complete control may be had over the temperature in the
jacket at all times, and by this means the quality of the product is
improved. By means of this steam pipe also the interior of the digestor
may be readily washed and cleansed at any time.
The employment of the devices for regulating the supply of hot air
to the interior of the central hot air cylinder is especially advantageous.
By means of these the supply of hot air may be partially or wholly cut
off at any time, and cold air may be admitted therein.
If desired an independent cold air pipe may be employed, as shown at
x, Figure 3. The employment of the rear curtain in the fire-box in
connection with the front curtain is advantageous, because thereby the
rapid and complete combustion of the foul gases is further facilitated.
If desired the hot air may be taken from the fire-box of the boiler
instead of employing a separate furnace.
If desired the central hot air cylinder may be divided more than once,
or may be divided diagonally or in any other propor manner, or it may
be formed if desired of a coil of pipe suitably covered and protected by
strainer plates.

page_text: ame, I wish it understood that I claim, the method of and apparatus for
endering fatty substances and animal matter as herein described.
In witness whereof, I, the said William Robert Lake, have here-
unto set my hand and seal, this Sixth day of February, in
the year of our Lord One thousand eight hundred and seventy-
five.
Witness,
H. J. NOONE.
WM. ROBT. LAKE. (L.S.)