Vegetable Extracts, and in Apparatus Employed therein.
Year: 1886

page_text: Date of Application, 29th Mar., 1886.
Complete Left, 29th Dec., 1886.
Complete Accepted, 1st Feb., 1887.
Vegetable Extracts, and in Apparatus Employed therein.!
I AUGUSTUS MORAND, of Philadelphia, in the State of Pennsylvania, United States
of America, Chemical Manufacturer do hereby declare the nature of this invention
to be as follows:-
This invention relates chiefly to the manufacture of tannin-extract from wood, but
it relates also to the making of sumac extract, and to extracts from dye-woods and
other vegetable extracts. The principal feature of the invention is an improved method
of clarifying or purifying the crude extract.
In manufacturing tannin-extract from wood I cut the wood transversely into thin
slices, break the slices into granules, place the granulated wood in a tank or vat, and
percolate water through the mass, until the soluble tannin has been dissolved out.
The water is passed through several tanks until the crude extract has acquired the
maximum density, when it is drawn off. The water is slightly acidulated either before
or during the percolation, or after the crude extract is drawn off. The crude extract
is then clarified, by stirring an alkaline solution of casein or other clarifying agent
into it until it is rendered neutral or nearly so. The extract is then forced under
heavy pressure through a dense filtering medium, which arrests the clarifying
substance, and the extract is filtered through. The purified extract is then con-
centrated in a vacuum pan, and is finally barrelled for the market.
I will now describe the apparatus :-There is first a wood cutting machine which
cuts thin slices from the end of the log of wood transversely to the grain, perferably at
an angle. A suction-tube leads from near this cutter to a centrifugal blower, and
from this blower, a delivery-tube extends up and into a long bin or receptacle, which
is divided into a series of compartments or small bins. The delivery-tube has valved
openings communicating with the respective compartments. Beneath the compartments
are a series of percolating tanks.
Chestnut wood is preferred, although oak and some other woods may be used. As
the slices of wood fall from the cutter, they are drawn into the suction-tube and, being
very brittle, are broken into small pieces. As they pass through the blower they are

page_text: reduced to small angular granules, and the wood thus granulated is carried by the
blast of air through the delivery-tube, and deposited in one or other of the compart-
ments or bins. These are filled one after another, and each holds one charge of wood.
In the bottom of each compartment is a trap-door, opening downward. When a tank
is to be filled, a shoot is placed over it, under the trap-door of the compartment above
the tank. The trap-door is then opened, and the granulated wood runs out of the
compartment, through the shoot into the tank. When the tank is full, the trap-door
is closed, and the shoot is removed.
Each tank has a perforated false-bottom, on which the mass of granulated wood
rests, leaving an open chamber below. Over each tank is arranged a rotating
sprinkler. From the bottom of each tank a pipe leads to a pump, and from this pump
another pipe leads up to the top of the sprinkler for the next successive tank in the
series. From the last pump a pipe extends back to the first tank, and empties into
the sprinkler thereof. The liquor which percolates down through the wood in either
tank is thus pumped up and passes through the sprinkler of the next tank.
A tank for fresh water, is provided from which a pipe extends over the row of tanks,
with a faucet over each sprinkler. Underneath the row of tanks is a drawing-off pipe,
which leads from the bottom of each tank to a clarifying tank or tanks.
The process of extracting is as follows:-The tanks contain granulated wood in
different conditions of depletion. In practice from 10 to 20 tanks will be used; but
assuming that only five are employed, No. 1 will contain the wood which is nearly
spent or exhausted of tannin; No. 2 that which is a little richer, and so on, No. 4 being
filled with new fresh wood. No. 5 is temporarily out of the series, because it is being
emptied of the spent wood or refuse, and filled with new wood. Fresh water preferably
heated to about 90° Centigrade, flows to the sprinkler of tank No. 1, and is sprinkled on
the nearly depleted wood in this tank, and slowly percolates down through the mass
collecting in the space in the bottom. The weak solution or liquor is then pumped up
and sprinkled over tank No. 2; after percolating through this tank, it is pumped up
to tank No. 3, each time meeting richer wood, and each time become a denser extract,
and becoming cooler until finally it passes through the fresh wood in tank No. 4,
thereby acquiring its maximum density. It is then drawn off from this tank into one
of the clarifying tanks. A small proportion of dilute sulphuric acid (or hydrochloric
acid) is added to the liquid, either by mixing it with the water beforehand, or,
preferably, by sprinkling it on to one of the tanks (No. 3 for example) or by stirring
it into the crude extract in the clarifying tank.
In order to clarify the crude extract, a clarifying solution is made as follows:-Take
skimmed milk, and coagulate its casein in any known way, preferably by hot water.
Wash the coagulum thoroughly. To each 50 grains of the pure casein take about one
grain of carbonate of soda (or other alkali) and dissolve in water. Dissolve the casein
in this alkaline solution. The alkaline solution of casein thus produced constitutes the
clarifying agent. Enough of this solution is gently stirred into the acidulous crude
extract to neutralize, or nearly so, the free sulphuric acid (or hydrochloric acid) in the
extract. The alkali combines with this acid, setting free or precipitating the casein in
a condition of fine flocculence. If the extract be of slight density, the casein will
gradually precipitate, leaving the extract clear and pure. But it is much better to
make the extract at as great a density as possible; and to separate the casein by
filtration.
From the clarifying tanks a pipe leads to a pressure pump and from this pump
another pipe leads to a "filter-press" of the usual construction. The extract, with the
flocculent casein suspended in it, is drawn off and forced by the pump through the
filter-press, the dense filter-cloths of which arrest the particles of casein, and all
suspended impurities, and a cake or layer is quickly formed over the cloths. The
remainder of the extract forced through this layer of cascin and through the cloth,
so that every particle of the extract is brought into contact with the casein. The result
is that the extract is rendered perfectly pure and clear, and of lighter color.
From the filter press the liquid enters a receiving tank, from which it is drawn off
to the vacuum-pan in which the extract is concentrated in vacuo. The concentrated

page_text: extract is then run off into one of a series of storage tanks, from which it may be drawn
into barrels as required.
If preferred the extraction may be effected by maceration instead of by percolation,
but as the maceration process is well understood I need not describe it.
The crude extract may be rendered alkaline, by adding an alkali in excess, and an
acid solution of casein may be used as the clarifying agent. Or, an alkaline solution
of casein may be used, and then enough more acid may be added to the extract to
neutralise it, and liberate the casein. In any case the casein will be dissolved in a solvent
which has a chemical affinity for some constituent of the extract, or for some substance
to be afterward added to the extract.
Instead of casein, any equivalent clarifying substance may be used. Albumen is
such a substance. The albumen of blood may be coagulated by heat, the coagulum
washed, and then dissolved in an alkaline solution.
The filtering process may be omitted altogether, or any ordinary filter may be used
in place of a filter-press.
The extract may be decolorized and purified by mixing with it any decolorizing
substance, such as blood or skimmed milk, for example, and then forcing it through
the filter-press.
For extracting dye-woods some modification of the process and apparatus may be
necessary. For making tannin-extract from bark, the bark should be ground. For
making sumac-extract, the sumac should be placed in the tanks; the process will then
proceed the same as with wood.
J. C. MEWBURN,
169, Fleet Street, London,
Agent.

page_text: Improvements in the Manufacture of Tannin-extract and similar
Vegetable Extracts, and in Apparatus Employed therein.
I, AUGUSTUS MORAND, of Philadelphia, in the State of Pennsylvania, United States
of America, Chemical Manufacturer, do hereby declare the nature of said invention for
"IMPROVEMENTS IN THE MANUFACTURE OF TANNIN-EXTRACT AND SIMILAR VEGETABLE
EXTRACTS, AND IN APPARATUS EMPLOYED THEREIN," and in what manner the same is
to be performed, to be particularly described and ascertained in and by the following
statement:
This invention relates chiefly to the manufacture of tannin-extract from wood, but
it relates also to the making of sumac extract, and to extracts from dye-woods and
other vegetable extracts. The principal feature of the invention is an improved
method of clarifying or purifying the crude extract.
In manufacturing tannin-extract from wood, I cut the wood transversely into thin
slices, break the slices into granules, place the granulated wood in a tank or vat, and
percolate water through the mass, until the soluble tannin has been dissolved out. The
water is passed through several tanks until the crude extract has acquired the maximum
density, when it is drawn off. The water is slightly acidulated either before or during
the percolation, or after the crude extract is drawn off. The crude extract is then
clarified, by stirring an alkaline solution of casein or other clarifying agent into it
until it is rendered neutral or nearly so. The extract is then forced under heavy
pressure through a dense filtering medium, which arrests the clarifying substance and
the extract is filtered through. The purified extract is then concentrated in a vacuum
pan, and is finally barrelled for the market.
The accompanying drawings illustrate the preferred apparatus. Figure 1 is an eleva-
tion in the nature of a diagram, showing all the apparatus for the factory. Fig. 2 is
a vertical transverse section of a portion of the factory. Fig. 3 shows the shoot in
section and end-view. Fig. 4 shows the tanks for extracting by the maceration-
process.
«
I will now describe the apparatus, referring principally to Fig. 1. A is the wood-
cutting machine or varlope," which cuts slices about 3 millimeters thick from the
end of the log of wood a, transversely to the grain, or preferably at an angle, as
shown. B is a suction-tube leading to a centrifugal blower C, and from this blower. a
delivery-tube D extends up and into a long bin or receptacle E which is divided into
a series of compartments or small bins F F. The tube D has valved openings d d
communicating with the respective compartments F. Beneath the compartments F F
are a series of percolating tanks G G.
Chestnut wood is preferred, although oak and some other woods may be used. As
the slices of wood fall from the cutter A, they are drawn into the suction-tube B, and,
being very brittle, are broken into small pieces. As they pass through the blower C
they are reduced to small angular granules, and the wood thus granulated is carried
by the blast of air through the tube D, and deposited in one or other of the compart-
ments F F, depending upon which of the openings d d is opened. The wood falls to

page_text: the bottom of the compartment while the air ascends and escapes through a ventilator b
at the top. (See Fig. 2.) The compartments F F are filled one after another, and
each holds one charge of wood. In the bottom of each compartment is a trap-door, c,
opening downward. A shoot I, (see Fig. 3) is provided to be fastened temporarily
under any of the trap-doors c c, as shown in dotted lines in Fig. 2. When a tank Ğ
is to be filled, the shoot I is placed over it, under the trap-door c of the compartment F
above the tank. The trap-door c is then unfastened, and it turns down into the
shoot I. The granulated wood then runs out of the compartment F, through the
shoot I, which directs it into the tank G. When it has all run out, and the tank is
full, the door c is closed, and the shoot I is removed.
Each tank G has a perforated false-bottom e on which the mass of granulated wood
rests, having an open chamber below. Over each tank is arranged a sprinkler H,
which is mounted on pivots, and as the water or liquor runs through it, it rotates and
sprinkles the liquid uniformly over the top of the wood. From the bottom of each
tank a pipe g leads to a pump J, and from this pump a pipe 7 leads up to the top of
the sprinkler H for the next successive tank in the series. From the last pump Ja
pipe extends back to the first tank G, and empties into the sprinkler H thereof.
The liquor which percolates down through the wood in either tank G is thus pumped
up and passes through the sprinkler H of the next tank. All the pumps J J are in
line, and are operated by a single reciprocating rod which is actuated by a crank i.
L is a tank for fresh water, and from it a pipe l extends over the row of tanks G G,
with a faucet over each sprinkler H. Underneath the row of tanks is a pipe m, and
from the bottom of each tank a pipe n closed by a valve, leads into this pipe m.
M. M are two clarifying tanks, into which open the outlet-valves o o from the pipe m.
The process of extracting is as follows:-The tanks G G contain granulated wood
in different conditions of depletion. In practice from 10 to 20 tanks will be used;
but, assuming that only 5 are employed, No. 1 will contain the wood which is nearly
spent or exhausted of tannin; No. 2 that which is a little richer, and so on; No. 4 being
filled with new fresh wood. No. 5 is temporarily out of the series, because it is being
emptied of the spent wood or refuse, and filled with new wood. Fresh water from the
tank L, preferably heated to about 90° degrees Centigrade, flows through the pipe / to
the sprinkler H of tank G, No. 1, and sprinkled on the nearly depleted wood in
this tank, and slowly percolates down through the mass, collecting in the space f in
the bottom. The wood, being uniformly granulated, packs together in a homogeneous
mass, in which the water hangs and soaks through slowly, so that it is forced to enter
all the cells and dissolve out the tannin very thoroughly. The weak solution or liquor
is then pumped up and sprinkled over tank No. 2; after percolating through this tank,
it is pumped up to tank No. 3, each time meeting richer wood, and each time becoming
a denser extract, and becoming cooler until finally it passes through the fresh wood
in tank No. 4, thereby acquiring its maximum density. It is then drawn off from this
tank through pipes n and m into one of the clarifying tanks M. A small proportion
of dilute sulphuric acid (or hydrochloric acid) added to the liquid, either by mixing
it with the water in the tank L, or, preferably, by sprinkling it onto one of the tanks
(No. 3 for example) or by stirring it into the crude extract in the tank M. The best
proportion of acid cannot be stated exactly; it will vary from one and one-half grains
to four grains of acid for each liter of water. Water containing lime requires more
acid than soft water. The effect of the acid is to cut or destroy the gummy or
resinous matters in the wood.
When the liquor coming through tank No. 1, becomes too weak for profit, the
several valves are changed, and the fresh water is run on to No. 2, while the extract
of maximum density is drawn off from No. 5. When No. 1 has been drained, the
refuse wood is emptied out, preferably by opening a door
(see Fig. 2) and shovelling out the refuse through this door.
in the side of the tank
The crude extract in the tank M is then clarified. For this purpose a clarifying
5 solution is made as follows: Take skimmed milk, and coagulate its casein in any known
way, preferably by hot water. Wash the coagulum thoroughly. To each 50 grains
of the pure casein take about 1 grain of carbonate of soda (or other alkali) and

page_text: dissolve it in water. Dissolve the casein in this alkaline solution. The proportion of
casein to alkali may vary somewhat, but as a rule no more alkali should be used than
will suffice to dissolve the casein. The alkaline solution of casein thus produced con-
stitutes the clarifying agent. Enough of this solution is gently stirred into the
acidulous crude extract to neutralize, or nearly so, the free sulphuric acid (or hydro-
chloric acid) in the extract. The alkali combines with this acid, setting free, or
precipitating the casein in a condition of fine flocculence. If the extract be of slight
density, the casein will gradually precipitate, leaving the extract clean and pure. But it
is much. better to make the extract at as great a density as possible and to separate the
casein by filtration.
From the clarifying tanks M M a pipe q leads to a pressure-pump Q, and from this
pump a pipe leads to a "filter-press" R. This filter-press is of the usual con-
struction, having a series of chambers formed by flanged plates with pieces of heavy
dense woven fabric between them, all being pressed together by a screw.
The pump
forces the liquid through the fabric, which is supported on the corrugated or grooved
surfaces of the plates. From the filter-press a delivery pipe t leads to an elevated.
storage tank (or tanks) T.
The extract, with the flocculent casein suspended in it, is drawn off and forced by the
pump through the filter-press R to the tank T. The dense filter-cloths arrest the
particles of casein, and all suspended impurities, and a cake or layer is quickly formed
over the cloths. The remainder of the extract is forced through this layer of casein
and through the cloth, so that every particle of the extract is brought into contact.
with the casein. The result is that the extract is rendered perfectly pure and clear,
and it is greatly decolorized, or lightened in color.
From the tank Ta pipe u leads to the vacuum-pan U, in which the extract is con-
centrated in vacuo. It should be reduced to a density of 25° to 30° Baumé. The
concentrated extract is then drawn off by a pipe v into one of a series of storage tanks
V V, from which it may be drawn into barrels as required.
The pipes are steam pipes, and yy are steam coils for heating the liquids in the
tanks Land M if desired.
My invention may be modified in many respects. For instance, the extraction
may be effected by maceration instead of by percolation. In this case the
tanks G G will be as shown in Fig. 4. Pipes will lead from a steam boiler to the
several tanks, and the outlets from the tanks will communicate by a pipe g with a
steam pipe or montjuice J. After the granulated wood has been placed in a tank G,
the tank is filled with acidulated water, steam is turned on, and the mass is boiled for
an hour or more. The liquor is then drawn off and forced by the montjuice J up into
a tank N, from which it flows through a pipe into the next tank G of the series.
The wood is usually subjected to about 12 boilings of one hour each.
The crude extract may be rendered alkaline, by adding an alkali in excess, and an
acid solution of casein may be used as the clarifying agent. Or, an alkaline solution
of casein may be used, and then enough more acid may be added to the extract to
neutralize it, and liberate the casein. In any case, the casein will be dissolved in a
solution which has a chemical affinity for some constituent of the extract; or for some
substance to be afterward added to the extract.
Instead of casein, any equivalent clarifying substance may be used. Albumen is
such a substance. The albumen of blood may be coagulated by heat, the coagulum.
washed, and then dissolved in an alkaline solution. But casein is preferable. I make
no claim to clarifying by stirring blood or albumen into the extract and then
congulating it by heat, as I am aware this method is old.
The filtering process may be omitted altogether, or any ordinary filter may be used
in place of a filter-press.
After the separation of the clarifying substance from the extract, the latter may be
further decolorized and purified by mixing with it any decolorizing substance, such as
blood or skimmed milk, for example, and then forcing it through the filter-press. This
filtering under
pressure may be done either hot or cold, but it is best to maintain a
temperature of from 50° to 60° Centigrade.
'

page_text: For extracting dye-woods some modification of the process and apparatus may be
necessary. For making tannin-extract from bark, the bark should be ground. For
making sumac-extract, the sumac should be placed in the tanks G G; the process will
then proceed the same as with wood.
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 improved method of clarifying tannin-extract, or other vegetable extract,
by mingling with it a solution of casein, or equivalent clarifying substance, the
solvent of which has an affinity for some constituent of the extract (or a substance
afterward added to the extract) whereby the clarifying substance is precipitated in
the extract, and finally separating the clarifying extract from the precipitate.
2. The use, for clarifying tannin-extract or other similar extracts, of casein or
albumen which has been coagulated, and the coagulum of which has been dissolved in
a solvent.
3. The improvement in the manufacture of tannin-extract which consists in
mingling with the acidulous crude extract a sufficient quantity of an alkaline solution
of casein or other clarifying substance to neutralize the free acid therein, whereby the
neutralizing and clarifying aro both accomplished at the same operation.
4. The improved method of purifying and decolorizing tannin-extract which
consists in stirring into it a clarifying or decolorizing substance, and then forcing the
extract, with this substance held suspended in it, through a dense filtering cloth,
under heavy pressure, whereby the clarifying substance is arrested and forms a layer
over the cloth, and the extract is filtered through both this layer and the cloth.
5. The improved method of extracting tannin from wood, which consists in cutting
the wood across the grain into thin slices, breaking these slices into granules, placing the
granulated wood in a tank, and percolating water through it, substantially as described.
6. The improvement in the art of manufacturing tannin extract from wood which
consists in cutting the wood into thin slices across the grain, carrying the slices
through a conduit by means of a pneumatic blast, whereby. they are broken into
granules, placing the granulated wood in a tank and percolating water through it,
first using water containing already some tannin in solution and finally using clear
water, substantially as set forth.
7. The combination of apparatus consisting of the wood-cutter A, the pneumatic
tube B, the blower C, the delivery tube D, the valved openings d 'd, the series of
compartments or bins F F, and the series of tanks G G.
8. Also, the trap-doors cc, opening downward from the bottom of the bins F F,
and the shoot I adapted to be attached under either door e to direct the discharge of
the granulated wood into the tank G.
9. The combination of apparatus for purifying the extract, consisting of clarifying
tank M, pipe, pressure-pump Q, pipe, filter-press R, delivery-pipe t, and storage-
tank T, operating as described.
J. C. MEWBURN,
169, Fleet Street, London,
Agent.