IMPROVE- MENTS IN RENDERING, PURIFYING, AND BLEACHING TALLOW, LARD, AND OTHER FATTY MATTER
Year: 1874

page_text: LETTERS PATENT to Joseph A. Miller, of Providence, State of Rhode
Island, United States of America, for the Invention of "IMPROVE-
MENTS IN RENDERING, PURIFYING, AND BLEACHING TALLOW, LARD, AND
OTHER FATTY MATTER." Partly a communication from abroad by
PROVISIONAL SPECIFICATION left by the said Joseph A. Miller at the
Office of the Commissioners of Patents, with his Petition, on the
8th January 1874.
I, JOSEPH A. MILLER, of Providence, State of Rhode Island, United
States of America, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN RENDERING, PURIFYING, AND BLEACHING TALLOW, LARD,
AND OTHER FATTY MATTER," to be as follows:-
The first part of this Invention is designed to prevent the offensive
odours which make the rendering of tallow, lard, or other fatty matter
a nuisance, and by the prevention of all offensive smells to enable such

page_text: rendering to be carried on as a business in or near cities and towns
without causing any annoyance to persons living in the immediate
neighbourhood of such establishments; for this purpose I connect a
pipe with the upper part of a rendering tank or digester, whereby the
steam and vapor are carried to a chamber having a valve which when
opened admits the steam and vapor into a tubular chamber having a
large number of small perforations; through these perforations the
steam or vapor is forced by the pressure, and is made to impinge
against the outer case in fine jets; here these jets of vapor meet with
fine jets of water, by which they are condensed. An outlet at the
bottom of this chamber carries off the condensed vapor and water by
a pipe, and an outlet on the sides of the same chamber is connected by
a pipe with a pump, by which the uncondensed vapours are drawn off,
and by means of this pump. forced through perforated pipes placed
within a tank partly filled with water, so as to pass through the water
in fine jets, thus completing the condensing and washing process.
Above the water, and within the said tank a number of trays containing
lime, charcoal, earth, or other absorbing agents, are placed, and the
condensed vapours, which are now free from steam, are passed in
succession through the same; after which they pass into the air puro
and free from all offensive odours. The water in this tank is con-
tinually renewed by means of a continuous supply and overflow.
The second part of the said Invention is designed to purify and bleach
the tallow, lard, or other fatty matter after it has been rendered, and
to remove all cellular tissues, and glutinous, albuminous, and coloring
or other foreign matter, and bleach the same, to produce an article free
from all impurities, hard, and solid, which will keep well at all seasons,
and be better adapted for the uses for which such materials are required.
This part of the said Invention is carried into practise in the following
manner :-
Into a tank supplied with either a steam jacket or a coil of steam
pipe, placed within the same, is placed one-fourth as much water as
there is tallow to be purified; in this water from two to two and a half
per cent. of strong sulphuric acid must be previously mixed; this is
now heated to from one hundred and fifty to two hundred degrees
Fahrenheit, and the tallow or lard added; the whole is well stirred, and
the temperature maintained at or near two hundred degrees for half
an hour, it is now allowed to settle, the temperature being maintained

page_text: for one hour or more.
Near this tank, but at a lower level, a second
tank is placed, having a steam jacket or a steam coil within the same,
and also a coil of perforated pipe connected with an air pump; into
this second tank I put from twenty to twenty-five per cent. of water,
having dissolved in the same from one-half to three-fourths of a pound
of alum to each hundredweight of tallow; the tallow or lard is drawn
from the first tank, so as to leave most of the water and the impurities
that have settled. The whole mass is now heated to a temperature of
two hundred degrees Fahrenheit, as soon as a temperature of two
hundred is reached the air pump is started, and air is forced into the
tank by means of the perforated pipe, and is forced through the whole
mass, being brought in contact with all particles, and the whole is
thoroughly mixed and agitated. This operation is continued for thirty
minutes, after which the mass is allowed to cool and settle, when all
water and impurities are drawn off from the bottom; the residue is now
again heated by steam to two hundred degrees, when the air pump is
again started, and air forced through the same. The temperature is
gradually increased to about two hundred and thirty degrees Fahrenheit,
and kept so for fifteen minutes or more, according to the quantity, and
until all water is expelled from the mass, when the temperature is
allowed to fall to about two hundred degrees, and allowed to settle.
Then the tallow or lard may be drawn into packages or moulds, and a
hard, white, pure, and sweet article is obtained, which will keep pure
and sweet in all seasons.
It is the practise to sometimes mix tallow with water containing
sulphuric acid before rendering, when this is the case the rendered
tallow is drawn directly into the second tank, then steam is admitted,
and the tallow is heated to two hundred and twelve degrees; the air
pump is started and air is forced through the same for from thirty to
sixty minutes, the heat being increased to about two hundred and thirty
degrees Fahrenheit, when, the air blast being stopped, the whole is
allowed to cool to two hundred degrees, which temperature is main-
tained for about one hour, when the mass is ready to be drawn into
casks or moulds.
When a very fine, white, and sweet tallow or lard is required the
air, before it enters the air pump, is drawn through a furnace in which
a clear coke fire is maintained, and small quantities of common bay
salt (chloride of sodium) are made to fall on the fire, so that the air is

page_text: charged with the products of combustion, carbonic acid, steam, and free
chloride, and is thus forced through the tallow or lard; by these means
an article of pearly white and of sweet flavour is obtained, that is very
firm, and will keep a long time; it is however necessary to finish by
blowing pure air through the tallow or lard for a short time after using
the above, and before allowing the mass to cool and settle.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Joseph A. Miller in the Great Seal Patent Office
on the 8th July 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOSEPH A.
MILLER, of Providence, Rhode Island, United States of America, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eighth day of January, in the year of
our Lord One thousand eight hundred and seventy-four, in the thirty-
seventh year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Joseph A. Miller, Her special licence
that I, the said Joseph A. Miller, my executors, administrators, and
assigns, or such others as I, the said Joseph A. Miller, 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 "IMPROVEMENTS IN
RENDERING, PURIFYING, AND BLEACHING TALLOW, LARD, AND OTHER FATTY
MATTER," upon the condition (amongst others) that I, the said Joseph
A. Miller, my executors 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 six calendar months next and
immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Joseph A. Miller, do hereby declare
the nature of my said Invention, and in what manner the same is to

page_text: 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:-
This Invention is designed to prevent the offensive odours which
make the rendering of tallow, lard, or other fatty matter a nuisance,
and thereby enable the operation of rendering to be carried on as a
business in or near cities and towns without causing any annoyance to
persons living in the immediate neighbourhood of such establishments.
The said Invention is also designed to purify and bleach the tallow,
lard, or other fatty matter after the same has been rendered, and to
remove all cellular tissues, and glutinous, albuminous, and coloring or
other foreign matter, and thereby produce an article free from all
impurities, hard, and solid, which will keep well in all seasons, and
will be better adapted for the uses for which such materials are
required.
DESCRIPTION OF THE DRAWINGS.
Figure 1 is a vertical section of an apparatus to be used in practising
my Invention; Figure 2 is a horizontal section of the same on the
line X, X, Figure 1; Figure 3 is a plan; and Figure 4, a vertical
section, illustrating a modified construction of the said apparatus.
Figure 5 is a section of a water attomiser; and Figure 6, a section
of a steam or vapour attomiser, forming part of my apparatus, as
hereinafter described.
Figure 7 is a vertical section of a condenser; Figure 8 is a plan of
part of the same; and Figures 9 and 10 are similar views of a washer,
both of which are herein-after described.
Similar letters refer to corresponding parts throughout the Drawings.
To prevent the contamination of the air by the noxious vapours from
a rendering tank I connect a pipe a from the rendering tank or
digester with the condenser d, which consists of a cylindrical vessel,
wherein an attomiser 6 or tubular vessel, with a great number of per-
forations, is placed. The steam, gas, and vapor are made to pass
through the fine holes in the attomiser 6 and to impinge against the
sides of the condenser d. By these means the gases are "diverted" to
a considerable extent, and when they meet the fine spray of water,
which is forced through the rose sprinkler or water atomizer c into the

page_text: condenser, the condensable portions of the gas and vapor are acted upon
in the most favorable manner and under the best possible conditions,
and the largest part of the gas or vapor is so condensed. Such parts
however as are not readily condensed are made to pass through the
pipe E into the washing vessel, while the condensed portion is carried
off with the water after entering the tub F.
When the uncondensed vapors reach the washing vessel G they pass
under the perforated plate into the space H, and ascend through the
water, and through small holes in the plates near their periphery, as
clearly shown in Figures 9 and 10. After passing through the holes
in the first or lowest plate they pass along in contact with water
to the holes in the outer portion of the upper plate, and by these means
are thoroughly washed and condensed. If the water is kept cool and
pure they will rise pure and sweet without any obnoxious smells. But
to further insure this result I now pass the gases into the chamber,
and filter them through trays containing lime, earth, charcoal, or other
good absorbent materials; after which I prefer to let the gases enter a
chimney, or, if convenient, a furnace, where they may be consumed.
When using the apparatus, shown in Figures 3 and 4 I pass the steam
and gases first through a separator X, and thence to the condenser. In
this case the water attomiser or sprinkler c is placed above the vapor
attomiser 6, and the shelves o, o, are so placed in the vessel F that the
condensed vapor and water will flow in thin films over the said plates,
and thereby allow any vapor not before condensed to separate and
meet the spray of water, and allow nothing but condensed water to fall
into the chamber F and be carried off through the overflow. The
uncondensed vapor and gas now pass through the pipe E into the
washing vessel G, and thence through the absorbent materials in the
chamber K, as before; but in this case the gases are forced downward,
whereby a letter result is obtained, and the gases are delivered perfectly
pure and sweet. In this process a pump may be used if required to
force the steam, vapor, or gas, through any one or all of the vessels; the
said pump may be located at any convenient position, in which it will
act partly by suction and partly by forcing the gases; or the said pump
may be at either end of the apparatus, so that it will act solely by
suction or solely by forcing, as may be best adapted to the circumstances
under which the apparatus is worked.

page_text: Having thus prevented the entrance of the gas into the atmosphere,
and the contamination of the latter, I next proceed as follows:—After
the tallow or lard is drawn from the rendering tank I place the residue,
while hot, as quickly as possible into bags, or into a hydro-extractor
lined with suitable cloth, and at once extract all the moisture, and with
this moisture also a large per centage of tallow or lard that has here-
tofore been lost; this process leaves the rest of the offal in a nearly
dry condition, and its pulverization to make a good fertilizer is greatly
facilitated. The rendering of the lard and tallow being in this manner
deprived of all noisome smells, so that the same as a business may be
carried on within or near cities and towns, I now proceed to purify and
bleach the lard or tallow so rendered as follows:-
-:
Tallow and lard when rendered in the usual manner contain large
quantities of minute cellular tissues filled with oleine and albumina,
which in their decomposition, particularly in the summer time; give
off offensive smells; they also contain glutinous matter, which de-
composes readily and gives off offensive odours. Tallow also contains
colouring matter, and when obtained from lean or unhealthy animals
is of a yellowish unsightly colour, and when mixed with other tallow
imparts a dingy and dirty appearance to the mass, which has to be sold
as an inferior article at a lower price than clear prime tallow; the oleine
easily separates from the stearine, and in summer keeps the tallow
from becoming hard and firm; and if packed in winter is liable to leak
through the packages in summer, giving the whole such an appearance
as to make it unmarketable.
To avoid these defects and produce tallow or lard free from all im-
purities, and in a hard and solid condition at all seasons of the year,
and which shall be sweet to the taste, and of a clear uniform color
throughout the whole mass, I proceed as follows, that is to say, into a
tank fitted either with a steam jacket or with a coil of steam pipes I
place water containing from 2 to 2½ per cent. of sulphuric acid. The
quantity of water used should be about one-fourth the quantity by
weight of the tallow to be purified. I then heat this water to 150 to
200 degrees Fahrenheit, and admit the tallow from the rendering tank;.
the temperature is maintained at 200° for half an hour, and the whole
thoroughly stirred, when the steam is turned off and the contents of the
tank allowed to settle for one hour or more, during which time the
temperature is not allowed to fall below 160°. Near this tank I place

page_text: a second tank, so far below it that the tallow from the first of these
two tanks may be drawn into the said second tank. The latter has a
steam jacket or coil, and also a perforated coil with an air pump. Into
this tank I place from 20 to 25 per cent. of water, having dissolved in it
from to % of a pound of alum for every 100 pounds of tallow. This
water is heated to 150° Fahrenheit, and the tallow from the first tank is
drawn into this second tank, so as to leave all the water and precipitated
impurities in the first tank. The whole mass is now heated to and
maintained at 200° Fahrenheit, and air is forced through it. in such a
manner as to bring the same into contact with every particle of the
mass. This operation is continued for 30 to 45 minutes when the mass
is allowed to cool and settle; I now draw off all the water, and as much
of the impurities as possible, and then heat the remaining tallow to 220°
or more, but not above 230 degrees Fahrenheit, and again force air
through the same for from 15 to 30 minutes. Then while the tem-
perature is maintained at about 200 Fahrenheit the mass isleft to settle,
when the tallow may be drawn off into moulds or packages. I thus
obtain a hard, pure, and white tallow, of uniform quality throughout
its entire mass, free from impurities, and which will keep a long time
sweet and hard, and will be considered a first rate article in the
market.
In some instances tallow and lard before being rendered are washed
in water containing a small per centage of sulphuric acid, such tallow
and lard I place directly into the second tank, heated to 230° Fahrenheit,
but not higher, and force air through the same for from 30 to 60
minutes. The proper time may be ascertained by the foam, which at
first is dark, and having been skimmed off becomes of a pearly white,
when the air pump is stopped. The mass is then allowed to cool to
about 200° Fahrenheit, and to stand for 15 to 30 minutes, when the
tallow or lard is ready for packing, and will be uniformly white, clear,
hard, and sweet, and of superior quality.
When wish to obtain a very superior article of lard or tallow of fine
pure white color and sweet taste I draw the air, before it enters the
pump, through a furnace in which a clear coke fire is maintained, and
upon which small quantities of common bay salt (chloride of sodium)
are allowed to fall, so that the products of combustion and the air will
take up some of the chloride and carry the same into the lard or tallow.
When the air so charged, has been blown through the tallow or lard.

page_text: heated above 212°, but not above 230° degrees Fahrenheit, for 20
minutes I disconnect the suction pipe of the pump and continue for
from 15 to 20 minutes with the pure air, when the mass is allowed to
cool, but not below 200° Fahrenheit, for about an hour, and is then
drawn off into moulds or packages. I thus obtain a very fine quality
of lard or tallow, which will be sweet and hard, and will keep in this
condition for a long time.
Having thus fully described my said Invention, and the manner of
performing the same, I wish it understood that I claim,-
First. In an apparatus for rendering tallow, lard, and other fatty
matter, the perforated tubular vessel or attomiser 6 employed in com-
bination with the water spray and the condenser d for desicating and
condensing steam, vapor, or gas, as herein specified.
Second. The washer G, with the double perforated plates and
chamber H, as herein set forth, and for the purpose specified.
Third The combination of the condenser d, the washer G, and the
chamber K fitted with the trays L containing suitable absorbent material
for freeing the gases from obnoxous vapors or other impurities.
Fourth. Purifying lard, tallow, or other fatty matter, by subjecting
the same in succession to the action of sulphuric acid, alum, and
atmospheric air.
Fifth. Bleaching or purifying lard or tallow by heating the same to
a temperature above 200° Fahrenheit and forcing atmospheric air
through the same.
Sixth. Bleaching and purifying tallow and lard by forcing air through
the same charged with vapors of salt (chloride of sodium) as specified.
JOSEPH A MILLED