Improvements in the Method of and Apparatus for Washing, Scouring, and Bleaching Wool.
Year: 1886

page_text: Date of Application, 23rd Nov., 1886.
Complete Left, 23rd Aug., 1887.
Complete Accepted, 23rd Sept., 1887.
Improvements in the Method of and Apparatus for Washing,
Scouring, and Bleaching Wool.
I THADDEUS ZEBROWSKI, Engineer of Moscow in the Empire of Russia do hereby
declare the nature of this invention to be as follows:-
Up to the present time, washing of wool has been ordinarily performed in hot
alkaline baths. This, besides being expensive, presents the essential deficiency, that
by the action of the alkaline matters partly contained in the wool itself and partly
added to the bath, a considerable percentage of the wool under treatment becomes
dissolved in the bath, and is thus lost.
As a remedy for removing this short-coming, I propose to effect the washing of
the wool in cold acid baths; thus, I take sulphuric acid in sufficient quantity
to convert into neutral salts the whole of caustic potash and carbonate of potassium
contained in the wool.
This quantity of sulphuric acid is diluted with sufficient water for the immersion
of the whole quantity of wool to be washed. When the wool is sufficiently washed in
this acid bath, the liquid is drawn off, and the washing is continued in pure water
till the water wrung from the wool runs off clear.
The wool thus washed is dried in the air, and is afterwards placed in a convenient
basket, and pressed (by means of a hydraulic or other press) under a pressure of
about 1 atmospheres.
The wool next undergoes the operation of scouring (ungreasing) and bleaching in
a special apparatus, to be described hereafter.
For scouring or ungreasing the wool, I use benzine, the use of which for this
purpose has heretofore been considered impossible, as benzine, when brought in contact
with wool, produces spontaneous combustion.
I have found that this combustion is owing to the electricity with which the wool
becomes charged when in contact with benzine. The electric sparks appearing
between the fibres of the wool are the cause of this ignition. The electricity may be
conducted away from the wool under treatment by making the bottom of the vessel
wherein the wool is treated, of different metals, as for instance copper and zinc.

page_text: Tutonule (6.0), whico,
combined with the humidity contained in the wool, forms sulphurous and hydrochloric
acid, as will be seen by the formula:
SO Cl, H₂O = SO, + 2 H Cl.
As wool dried in the air contains about 9% humidity, the quantity of Chloride of
Thionule to be added to the benzine is determined according to this degree of
humidity.
I have also found that the process of scouring (ungreasing) and bleaching wool is
performed with considerably greater success in rarefied air, and lastly, that the
ungreased and bleached wool becomes much softer and better in every respect, if it
is treated at last with weak sulphuric acid, taking, for instance, 1 pound of acid
(66° Baumé) to 700 pounds of water.
The apparatus which I use for the purposes of my invention consists of:
1. An extractor, in which is placed an iron basket filled with wool, pressed as afore-
mentioned. The extractor is provided with a gauge-glass, a manometer, a cock for
letting in the water, and an aperture by means of which it communicates with a
suction pump.
In the upper part of the extractor, above the level of the wool, are
two apertures, whose destination is explained below.
2. A reservoir filled with a mixture of benzine and Chloride of Thionule (SO C₁₂).
This reservoir is connected with the Extractor, and provided with an aperture for
filling it with the aforesaid liquid. Besides, this reservoir is connected with a lower.
reservoir or receptacle, the object of which will be presently explained.
3. A cistern which cominunicates with the lower part of the extractor.
4. A distilling-vessel which is connected with the extractor and with a cooler or
condenser, and is provided with a serpentine-pipe for heating by steam, a cock for
running off the grease, and a man-hole for cleaning.
5. A cooler or condenser for condensing the benzine vapours.
6. Two exhausters communicating with the cooler, with a suction pipe, and with
the lower reservoir or receptacle, in which is collected the benzine condensed in the
cooler.
7. A lower reservoir or receptacle provided with an air cock, and communicating
with the suction pump and with the benzine reservoir, as before-mentioned. All
parts of the apparatus, with the exception of the bottom of the extractor, can be made
of iron, but the serpentine-pipe in the distilling-vessel is, by preference, made of
copper; the bottom of the extractor consists of concentric copper and zinc rings,
soldered together alternately a copper ring being outside, the centre plate or disc
being likewise of copper. From each of these rings, start wires (of the same metal
as the corresponding rings), which are connected with the earth.
The action of the apparatus described is as follows:-
The wool, first washed in a cold sulphuric acid bath and then in pure water, is dried
in the air, and pressed as described above. It is then put in an iron basket, and
placed in the extractor, the air in which is rarefied to about 600 millimeters. The
benzine, mixed with Chloride of Thionule (SO. Cl₂), is then allowed to enter in the
extractor, and ungreases the wool therein, the formation of electric sparks, caused by
the action of benzine on the wool, being prevented by the above described construction
of the bottom of the extractor.
The wool is left in the extractor under the action of benzine for about an hour, at
the expiration of which time the benzine, together with the wool grease dissolved in
the same, is drawn off into the distilling-vessel for distilling the benzine off. When the
whole of the benzine is drawn off, the extractor is set in communication with the
cooler and one of the exhausters.
In these exhausters alternately the air is rarefied by means of the suction pump,
whereupon the benzine remaining in the wool is vaporised, and goes from the extractor
into the exhauster.
The benzine vapours passing through the cooler, condense and run in the exhauster.
For removing the last traces of benzine and grease from the wool, water from the
cistern is admitted into the lower part of the extractor. This water passing through

page_text: the wool from below, carries away the last traces of benzine, with the grease dissolved
in the same, and runs off through apertures. When this washing of the wool is ended,
the water is drawn from the extractor by a suitable cock.
For distilling the benzine from the grease dissolved in the same, the benzine
collected in the distilling-vessel is heated by steam admitted in the serpentine-pipe ;
at the same time, the air in the exhausters is rarefied, and the benzine vapors are
sucked in by the cooler, where they condense and run through the exhausters into the
lower reservoir. From this reservoir the benzine is caused to rise into its reservoir
by creating a vacuum therein.
As the distilling of the benzine is taking place, the wool washed with water is taken
from the extractor, which is refilled with a new quantity of wool, so that practically
the action of the apparatus is continuous.
When taken from the extractor, the scoured (ungreased) wool undergoes, as afore-
mentioned, a final washing in weak (700) sulphuric acid, whereby it is freed from the
last particles of impurity, and upon washing it once more in pure water, it appears
soft and white.
The wool washed according to my method gives a yarn of incomparably greater
strength, taking and keeping dye much better than any obtained from wool washed
in the ordinary way.
Besides, an essential advantage of my method is, as already mentioned above, that
the wool is not dissolved, as is the case with the use of hot alkaline baths, and
that at the same time the wool grease is obtained, which, in the ordinary washing, is
entirely lost.
NEWTON & SON,
Agents for the Applicant.

page_text: As a remedy for removing this short-coming I propose to effect the washing of the
wool in cold acid baths; thus, I take sulphuric acid in sufficient quantity to convert
into neutral salts the whole of the caustic potash and carbonate of potassium contained
in the wool.
This quantity of sulphuric acid is diluted with sufficient water for the immersion
of the whole quantity of wool to be washed. When the wool is sufficiently washed
in this acid bath, the liquid is drawn off, and the washing is continued in pure water
till the water wrung from the wool runs off clear.
The wool thus washed is dried in the air, and afterwards placed in a convenient
basket, and pressed (by means of a hydraulic or other press) under a pressure of about
1 atmospheres.
The wool next undergoes the operation of scouring (ungreasing), and bleaching, in
a special apparatus to be described hereafter.
For scouring or ungreasing the wool, I use benzine, the use of which for this
purpose has heretofore been considered impossible, as benzine, when brought in contact
with wool, produces spontaneous combustion.
I have found that this combustion is due to the electricity with which the wool
becomes charged when in contact with benzine. The electric sparks appearing
between the fibres of the wool are the cause of this ignition. The electricity may be
conducted away from the wool under treatment by making the bottom of the vessel
wherein the wool is treated of different metals, as for instance copper and zinc.
I employ the benzine mixed with chloride of thionule (SO CI,) which, combined
with the humidity contained in the wool, forms sulphurous and hydrochloric acid, as
will be seen by the formula :-
SO C₁₂+H₂O SO,+ 2 H Cl.
=
As wool dried in the air contains about 9% humidity, the quantity of chloride
of thionule to be added to the benzine is determined according to this degree of
humidity.
I have also found that the process of scouring (ungreasing) and bleaching wool is
performed with considerably greater success in rarefied air, and lastly, that the
ungreased and bleached wool becomes much softer and better in every respect, if it is
treated at last with weak sulphuric acid, taking, for instance, 1 pound of acid
(66° Baumé) to 700 pounds of water.
In the accompanying drawing I have shown the improved apparatus for effecting
the object of my invention, at Fig. 1.
This apparatus consists of;
(1) An extractor A, in which is placed an iron basket filled with wool pressed as
before mentioned. The extractor is provided with a gauge glass a, a manometer 6, a
cock c for letting in the water, and an aperture d, by means of which it communicates
with a suction pump, not shown in the drawing. In the upper part of the extractor,
above the level of the wool, are two apertures e e, the use of which is explained
below.
(2) A reservoir B filled with a mixture of benzine and chloride of thionule (SO (1,).
This reservoir is connected with the extractor A by means of the cock f, and is provided
with an aperture g for filling it with the aforesaid liquid. This reservoir is also
connected, through the cock h and the pipe i, with the reservoir C, the object of which
will be presently explained.
(3) A cistern D, which is filled with water through the aperture k, and communi-
cates with the lower part of the extractor A by means of a pipe and the cock c.
(4) A distilling vessel E, which is connected with the extractor A by the cock 1, and
communicates by means of the pipe m with a cooler or condenser F; the distilling
vessel E is further provided with a serpentine-pipe n, for heating by steam the contents
of the vessel, a cock o for running off the grease, and a man-hole p for cleaning out
the vessel.
(5) A cooler or condenser F for condensing the benzine vapours.
(6) Two exhausters G₁ and G", communicating with the cooler F by means of the
cocks q' and y", and with a suction pump, not shown in the drawings, through the

page_text: apertures and ". The exhausters communicate by means of the cocks s' and s¹¹
with the reservoir C, in which is collected the benzine condensed in the cooler F and
the exhausters G and G. Each of these exhausters is provided with a gauge-glass t,
a manometer u, and an air valve or cock v.
(7) A reservoir C, provided with an air cock x, and communicating, through the
aperture y, with the suction pump, not shown in the drawing, and by the pipe i with
the benzine reservoir B, as beforementioned. All parts of the apparatns, with the
exception of the bottom of the extractor A, can be made of iron, but the serpentine
pipe n in the distilling vessel E is by preference made of copper; the hottom of the
extractor A consists of concentric copper and zinc rings soldered together alternately
(see Fig. 2), a copper_ring being always outside, and the centre plate or disc being
likewise of copper. From each of these rings start wires (of the same metal as the
corresponding rings), which are connected with the earth.
The action of the apparatus described is as follows:-
The wool, first washed in a cold sulphuric acid bath and then in pure water, is dried
in the air, and pressed as described above. It is then put in an iron basket and placed
in the extractor A, which is hermetically closed with a lid. The air in the extractor
is rarefied to about 600 millimeters, and after shutting the cock of the manometer b,
the cock is opened, in consequence whereof the benzine mixed with chloride of
thionule (SO CI) contained in the reservoir B, enters the extractor A, and ungreases
the wool therein; the formation of electric sparks caused by the action of benzine
on the wool being prevented by the above described construction of the bottom in the
extractor.
The wool is left in the extractor under the action of benzine for about an hour, at
the expiration of which time, the benzine, together with the wool grease dissolved in
the same, is drawn off by the cock into the distilling vessel E, for distilling the
benzine off. When the whole of the benzine is drawn off from the extractor, the
cock is shut, and by opening the cock j, the extractor is set in communication with
the cooler F and one of the exhausters G₁ and G" (according to which of the cocks q¹
org is opened).
In these exhausters alternately the air is rarefied by means of the suction pump,
not shown in the drawing, the benzine remaining in the wool is vaporised, and goes
from the extractor A into the exhauster G¹ or G¹¹ which is connected with the
extractor. The benzine vapours passing through the cooler F, condense, and run
into the exhauster. For removing the last traces of benzine and grease from the wool,
water from the cistern D is admitted into the lower part of the extractor by the cock c.
This water passing through the wool from below, carries away the last traces of
benzine with the grease dissolved in the same, and runs off through the apertures e e
of the extractor into a special reservoir, not shown in the drawings, where the benzine
separates from the water. When this washing of the wool is ended, the water is
drawn from the extractor A by the cock H.
For distilling the benzine from the grease dissolved in the same, the benzine collected
in the distilling vessel E is heated by steam admitted in the serpentine pipe n. At
the same time the air in the exhausters G₁ and G" is rarefied, and the exhausters
alternately set in communication (by opening the cock q' or 7") with the distilling
vessel E; in consequence hereof the benzine vapours are sucked into the cooler F,
where they condense and run through the exhausters into the reservoir C. From
this reservoir, the benzine is caused to rise into its reservoir B, for which purpose
the air in the latter is rarefied, through the aperture z communicating with the
suction pump, not shown in the drawing, and the air cock on the reservoir C
opened.
The reservoir B contains double the quantity of liquid required for once filling the
extractor A.
While the distilling of the benzine is taking place in the distilling vessel E, the
wool washed with water is taken from the extractor, which is refilled with a new
quantity of wool, so that practically the action of the apparatus is continuous.
When taken from the extractor, the scoured (ungreased) wool undergoes, as before-

page_text: mentioned, a final washing in weak (760) sulphuric acid, whereby it is freed from
the last particles of impurity, and upon washing it once more in pure water, it appears
soft and white.
The wool washed according to my method gives a yarn of incomparably greater
strength, taking and keeping dye much better than any obtained from wool washed in
the ordinary way.
Besides, an essential advantage of my method is, as already mentioned above, that
the wool is not dissolved, as is the case with the use of hot alkaline baths, and that at
the same time the wool grease is obtained, which in the ordinary washing is entirely
lost.
By experiments made, it has been proved that in washing by my method, the
Caucasian wool called "Negretti," 100 pounds of dirty wool yield about 36 pounds
clean bleached wool, whilst the same wool washed in the ordinary way yields not more
than 25 pounds wool of inferior quality; besides, by using my method, 19 pounds
wool grease are obtained.
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 above described method of washing and bleaching wool, whereby these
operations are affected more rapidly than heretofore; the wool is not destroyed, and a
valuable bye-product, in the form of wool grease, is obtained, as set forth.
2. The use of rarefied air for promoting the absorption of benzine by the wool.
3. The use of benzine for scouring (ungreasing) wool when employed in combina-
tion with the means above described, or similar means, for leading away the electricity
developed in the wool.
4. The use of chloride of thionule (SO CI,) combined with benzine for bleaching
the wool.
5. The apparatus for cold washing of wool in rarefied air, consisting of the extractor A,
the reservoirs B and D, the distilling vessel E, the cooler F, the exhausters Gland G",
and the reservoir C, for collecting the distilled benzine, such parts being connected
together by pipes and cocks, as above described and shown in the annexed drawing.
6. The construction of the bottom of the extractor, consisting of concentric copper
and zinc rings or other suitable metals set in electric connection with the earth, and
serving to lead away the electricity developed by the action of benzine on wool.
Dated this 23rd day of August 1887.
NEWTON & SON,
Agents for the Applicant.