An Improved Method of and Apparatus for Removing Tar, Pitch, Oil, Grease, and similar Matter from Wool, Fur, and the like.
Year: 1895

page_text: Date of Application, 28th Aug., 1895
Complete Specification Left, 27th June, 1896-Accepted, 1st Aug., 1896
PROVISIONAL SPECIFICATION.
An Improved Method of and Apparatus for Removing Tar, Pitch, Oil,
Grease, and similar Matter from Wool, Fur, and the like.
We, SAMUEL WRIGHT WILKINSON, Doctor of Philosophy, and THE GROVE
COMPANY LIMITED, Chemical Manufacturers, both of 17 Coleman Street, in
the City of London, do hereby declare the nature of this invention to be as
follows:-
This invention relates to an improved method and apparatus for removing tar,
pitch, oil, grease and similar matter from wool, fur and the like and is chiefly
designed to effect the treatment of such materials when in a felted condition as
used in the manufacture of felt hats.
"
Hitherto a large amount of loss has been incurred in the manufacture of felt
hata from the lower grades or classes of wool, from the presence in such wool of
tar, pitch, oil, grease and similar matter which has been applied thereto in the
marking or branding of the animals or is found therein froin natural or other
sources. This tar, pitch and similar matter when present in a felt "form," i.e. a
piece of felted wool or fur from which a hat should be made, renders that "form
of inferior quality and value as, when it is afterwards heated during the processes
incidental to the manufacture of a hat, the said tar, pitch or the like generally
spreads and causes an unsightly stain whilst at the same time it prevents any dye
which may be afterwards applied to the felt, from acting upon and colouring the
fibres thereof at the soiled part. Various attempts have been made heretofore to
remove this foreign matter chiefly by means of solutions of caustic soda or by
emulsions of oil and soda the felt forms being impregnated with such solutions or
emulsions and afterwards subjected to hand scouring but none of the methods have
been wholly satisfactory being uncertain in their action and not cleaning the felt or
wool sufficiently to enable it to be dyed by many of the dyes now in use.
Now according to our said invention we provide for removing or extracting the
said tar, pitch and other matter by means of a suitable solvent thereof such as
benzol or carbon bi-sulphide which is passed through the felt, wool or other material
a sufficient number of times to remove the tar, pitch, grease or the like therefrom,
our said invention also comprises means for removing the solvent remaining in the
felt after the said material has been cleansed and for collecting the solvent so
removed in order that it may be used again for subsequent operations, the
dissolved matter being occasionally removed therefrom by distillation or in any
other suitable manner, when necessary. The solvents which act satisfactorily are
few in number and relatively costly hence it is essential when using them to have
a suitable arrangement for recovering the same. From numerous experiments we
find that the solvent niost effective is benzol boiling below 100° C. the purest form
boiling at 80° C.
In carrying our said invention into practice we provide a closed vessel or
chamber to receive the felt or the like to be cleansed. This vessel is adapted to
withstand a certain amount of pressure and is provided with a suitable opening
capable of being closed by a removable manhole or cover whereby the felt or other
material may be readily introduced or removed. Suitable means, such as a steam or
hot-water coil or jacket are also provided whereby dry heat may be applied to the
contents of the said vessel.
We also provide a boiler, kettle or other suitable vessel for containing the

page_text: solvent, this vessel is provided with means, such as a steam or hot-water coil or
jacket whereby the contents thereof may be heated and volatilized. This vessel is
in communication through a suitable pipe or the like with a suitable distributing
pipe in the upper part of the vessel containing the wool or other material to be
cleansed so that the said material is thoroughly perineated by the solvent issuing
from the said distributing pipe. When the liquid produced by the condensation
of the vapour of the said solvent has accumulated in the extracting vessel to a
predetermined level it is automatically returned to the boiler by means of a syphon
one limb of which is in communication with the bottom of the said extractor and
the other limb with the interior of the boiler, the relative vertical heights of the
said limbs being such as to determine the direction of flow from the extractor to
the boiler. This operation is repeated a sufficient number of times to completely
remove the tar, pitch or the like after which the boiler is allowed to cool and
the communication between it and the extractor closed by means of a suitable cock
or valve.
In order to remove the portion of the solvent still remaining in the fibres of or
held in the body of telt or the like we apply heat to the extractor or vessel
containing the same by means of the coil or jacket above mentioned so as to
vaporize the solvent therein and we conduct the vapour so produced into a suitable
condenser where the said vapours are condensed and returned to the boiler in a
liquid state, suitable communicating pipes controllet by cocks, valves or the like
being provided for this purpose. When the solvent has been distilled off from the
extractor, the said extractor may be opened and the cleansed felt forms removed,
the communication between the said extractor and the condenser or boiler being
preferably closed in the meanwhile so as to prevent any loss of the solvent by
evaporation. We preferably provide suitable safety-valves on the boiler and
extractor and also suitable filling and drain-cocks or the like on the boiler or
elsewhere as required for the introduction and removal of the solvent. We also
provide suitable means whereby access may be had to the interior of the boiler for
cleaning or other purposes.
Dated this 28th day of August 1895.
D. YOUNG & Co.,
11 & 12 Southampton Buildings, London, W.C.,
Agents for the Applicants.
An Improved Method of and Apparatus for Removing Tar, Pitch, Oil,
Grease, and similar Matter from Wool, Fur, and the like.
We, SAMUEL WRIGHT WILKINSON, Doctor of Philosophy, and THE GROVE
COMPANY LIMITED, Chemical Manufacturers, both of 17 Coleman Street, in
the City of London, do hereby declare the nature of this invention 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 to an improved method of and apparatus for removing tar,
pitch, oil, grease and similar matter from wool, fur, and the like, and is chiefly
designed to effect the treatment. of such materials when in a felted condition as
used in the manufacture of felt hats.
Hitherto a large amount of loss has been incurred, in the manufacture of felt
hats from the lower grades or classes of wool, by reason of the presence in such
wool of tar, pitch, oil, grease and similar matter which has been applied thereto in
the marking or branding of the animals, or exists therein from natural or other
causes. This tar, itch and similar matter, when present in a felt "form," i.e. a
piece of feited wool or fur such as those from which hats are usually made, renders
1

page_text: that "form" of inferior quality and value, as, when such "form" is afterwards heated
during the processes incidental to the manufacture of a hat, the said tar, pitch, or
the like generally spreads and causes an unsightly stain, besides preventing any
dye, which may be afterwards applied to the felt, from acting upon and colouring
the fibres thereof at the soiled part.
Various attempts have been heretofore made to remove this foreign matter,
chiefly by means of solutions of caustic soda or by emulsions of oil and soda, the
felt "forms" being impregnated with such solutions or emulsions and afterwards
subjected to hand-scouring, but none of the methods have been wholly satisfactory,
being uncertain in their action and not cleaning the felt or wool sufficiently to
enable it to be dyed by many of the dyes now in use.
Now according to our said invention we provide for removing or extracting the
said tar, pitch and other matter by means of a suitable solvent thereof such as benzol
or carbon bi-sulphide, which is passed through the felt, wool or other material a
sufficient number of times to remove the tar, pitch, grease or the like therefrom.
Our said invention also comprises means for removing the solvent remaining
in the felt or the like after the same has been cleansed, and for collecting the
solvent so removed in order that it may be used again for subsequent operations,
the dissolved matter being occasionally eliminated from the collected solvent by
distillation or in any other suitable manner when necessary. The solvents which
act satisfactorily are few in number and relatively costly, and hence it is essential,
From
when using the same, to provide suitable means for recovering them.
numerous experiments we find that the solvent most effective is benzol boiling
below 100° C, the purest form boiling at 80° C.
In the accompanying drawing we have shown, in sectional elevation, a con-
venient and advantageous arrangement of apparatus for carrying our improved
method into practice.
a is a closed extracting vessel or chamber to receive the felt "forms" or the
like to be cleansed. This vessel is adapted to withstand a suitable internal
pressure, being closed by a removable cover or by a cover provided with a
manhole so that the felted wool or other material may be readily introduced
or removed. A steam or hot-water coil c or a jacket or other suitable means
are provided whereby dry heat may be applied to the contents of the said
vessel.
d is a boiler or other suitable vessel for containing the solvent, this vessel is also
provided with a steam or hot-water coil e or a jacket or other suitable means
whereby the contents thereof may be heated and volatilized. This boiler d is in
communication through a suitable pipe f provided with cocks or valves 1, 2, with
the upper part of the extracting vessel a. The lower end of the vessel a is also in
communication with the top of the boiler d through a siphon g, which is provided
with a cock or valve g', the relative vertical heights of the two limbs of the said
siphon being such as to determine the direction of flow from the extractor to the
boiler.
A condensing coil or worm his connected with the pipe fat its upper end by a
pipe j, and at its lower end by a pipe k provided with a cock or valve k'.
The condensing coil h is preferably also connected with the vessel a by a pipe p
provided with a cock or valve p¹ for the purpose hereinafter specified.
In treating felts or the like by our improved method in the apparatus above
described, we place in the vessel a a suitable quantity of the said felts or the like
and tightly close the said vessel. The cocks f' and k¹ being closed and the
cocks, pl and glopen, heat is applied to the boiler d so as to vapourize the
solvent therein. The vapour therefrom passes through the pipes and j into
the condensing worm h in which such vapour is condensed. The liquefied solvent
flows through the pipe p into the extractor a and dissolves the tar, grease or the
like contained in the felts, the latter being thoroughly permeated by the said
solvent. Any vapour that may enter the vessel a through the pipe p will be
condensed in the said vessel. When the liquid solvent has accumulated in the

page_text: extractor or extracting vessel to the level of the top of the siphon, it is auto-
matically returned to the boiler by means of the said siphon. The above-described
operation is repeated a sufficient number of times to completely remove the tar,
pitch, or the like from the wool or other material, after which the boiler d is
allowed to cool and the communication between it and the extractor is closed by
means of the cock or valve f¹.
In order to remove such quantity of the solvent as may still remain in the fibres
or be held in the body of the felt or the like in the vessel or extractor a, we close
the cock and open the cocks and k¹ and apply heat to the said extractor by
means of the coil or jacket e so as to again vapourize the said solvent; the vapour
so produced passes through the pipes and j into the condenser wherein the said
vapour is condensed and from which the liquid of condensation is returned to the
boiler through the pipes k and f.
The
In practice, we find that a certain amount of solvent is retained by the cleaned
felts which cannot be removed by simply heating the vessel a; in order to remove.
this without loss, we run hot water (heated to a few degrees below the boiling
point) from a tank m into the vessel a containing the felts, until it is nearly filled,
the siphon-tube g being closed while the hot water is in the vessel a.
temperature of the water being above the boiling point of the solvent remaining in
the felts, the said solvent is driven off in a gaseous condition and is condensed
and returned to the boiler d as above described, the water being afterwards run off
through a drain-cock .
When all the solvent has thus been distilled off and removed from the extractor a,
the said extractor may be opened and the cleansed felts removed, the communications
between the said extractor and the condenser and boiler being preferably closed mean-
while, so as to prevent any loss of the solvent by evaporation. We provide, if
necessary, suitable safety-valves on the boiler and extractor and also suitable
filling and drain-cocks or the like on the boiler or elsewhere as required for the
introduction and removal of the solvent. We also provide for permitting access to
the interior of the boiler for cleaning or other purposes.
When it is desired to eliminate the dissolved matter from the solvent collected
in the boiler d, this may be accomplished by closing the cocks f², k¹ and g¹ and
opening the cocks f³ and p¹, and then applying heat to the boiler d. The vapour
from the boiler will then pass into the condenser and the liquefied solvent will
run into and be collected in the vessel a, whence it may be returned to the boiler d
after the residue has been withdrawn therefrom.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is:
First. The herein described method of eliminating tar, pitch, oil, grease and
sin.ilar matter fron: felted and other wool, fur and the like by means of a volatile
solvent, such as benzol or carbon bi-sulphide.
Second. The herein described method of recovering the last traces of the solvent
from the treated felt or the like, by running hot water into the extracting vessel
to vaporize the solvent and then condensing the vapour and returning the liquefied
solvent to the boiler.
Third. The improved apparatus constructed substantially as described with
reference to the accompanying drawing and operating as and for the purposes
above specified.
(
Dated this 27th dex of fun 1906
D. YOUNG & Co.,
11 & 12 Southampton Buildings, London, W.C.,
Agents for the Applicants.