An. Improved Process for Separating Vegetable Impurities from Wool.
Year: 1893

page_text: Date of Application, 4th May, 1893-Accepted, 10th June, 1893
CUM LEIE UITIATION.
An. Improved Process for Separating Vegetable Impurities
from Wool.
We, TULLIO Buzzi, of Prato, Tuscany, Professor of Chemistry, and
RAFFAELLO MENOCHIO, of Prato, Tuscany, Director of the Royal School of
the Industrial Arts, 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 process for separating weeds, straw, and
such like impurities from wool, and cotton, and other vegetable fibres from woollen
rags by carbonisation.
According to this invention we heap up wool or rags to be treated upon a
horizontal grating dividing a chamber into two compartments, an upper and a
lower one.
Close by the said chamber we provide a cast iron boiler or other
suitable vessel in which we prepare dry hydro-chloric acid by heating a mixture
of sulphuric acid and ordinary salt, a suitable furnace being provided below the
boiler or other vessel for the purpose of heating the material. The dry hydro-
chloric acid generated is led into the lower compartment of the chamber from
which is passes upwards through the grating and the wool or rags resting thereon.
From this upper chamber the gas is drawn by means of an extractor, ventilator,
or other device and is passed through iron tubes which are heated either by direct
fire or by steam to a temperature of about 75 degrees C. when it is again con-
ducted to the lower compartment and passed through the wool or rags, this
circulation being maintained for a period of from 6 to 8 hours. Any of the gas
not absorbed at the end of this process is passed into water by which it is dissolved
and prevented from escaping into the atmosphere.
The effect of the dry hydrochloric acid is totally different to that which would
be derived by the use of the gas obtained by the heating of commercial hydro-
chloric acid over which it possesses many advantages. Among these may be
mentioned the expenses are less; it is possible to work at a very low temperature
therefore the wool is not injured; it is not necessary to beat the heated rags when
taken out of the chamber as the cotton becomes pulverised even when in a cold
state therefore there is less waste of woolly fibre. The gas is almost entirely
absorbed by the wool so that there is very little offensive smell in the neighbourhood
of the works where the process is carried on which may therefore be situated in
or near towns and other populated districts, any residue of gas unabsorbed being
dissolved in water. The colours remain unchanged, the whites retaining their
purity and not becoming yellow. The iron and brick work employed in the con-
struction of the factory or works are not injured. The rags remain soft to the
touch of the hand. A considerable saving is effected in the subsequent process of
dyeing with log-wood &c. The residue of the boiler is readily saleable for other
industrial purposes.
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 :-
The hereinbefore described method of separating vegetable impurities from wool
consisting in subjecting the same to the action of a current of dry hydrochloric
acid prepared by submitting the mixture of sulphuric acid and salt to the action
of heat, the dry gas being circulated several times through the woolly matter and

page_text: being heated between each application substantially as and for the purpose herein-
before described.
ALL JM. 1002
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CASTLE SMITH,
Invention" Office, 54, Fleet Street, London, E.C.,
Agent for the Applicants.
CASTLE SMITH,
Invention" Office, 54, Fleet Street, London, E.C.,
Agent for the Applicants.