Improved Process for Obtaining Turpentine from Wood and Wood Waste.
Year: 1896

page_text: Date of Application, 18th Nov., 1896-Accepted, 9th Jan., 1897
COMPLETE SPECIFICATION.
Improved Process for Obtaining Turpentine from Wood and
Wood Waste.
I, ADOLF SOHMIDT of 49 Kælnische Strasse, Cassel, in the German Empire,
Director of the Acticngessellschaft fur Treber Trocknung, do hereby declare the
nature of this invention and in what maunor the samo is to bo performed, to be
particularly described and ascertained in and by the following statement, that is
to say :-
In the dry distillation of wood, it has been shown that, before the actual
distillation of wood rich in resin, that is, before obtaining acetic acid therof rom,
another valuable product, viz. turpentine, may be obtained.
The latest improved process of distillation consists in forming the wood waste,
or saw-dust, in the driest possible condition, into briquettes, and then subjecting
these to distillation in suitable retorts.
To obtain from woods rich in resin, the turpentine that is in them, I adopt the
following process before beginning the actual distillation.
I first fill the retorts, in any suitable manner, with the briquettes, and then
heat said retorts to about 120° C. I then adinit stoam, which must be as dry as
possible, into the interior through a tube fixed in the bottom of these retorts,
preferring to use steam of some slight pressure. This drives out the turpentine
contained in the wood, which passes off with the current of steam, and is thrown
down and collected in suitable condensing apparatus. The steam is admitted ao
long as a sufficient quantity of turpentine collects in the condensing apparatus.
It is of extreme importance to watch the admission of steam carefully, as, if
continued too long, it would have an injurious effect on the subsequent process of
distillation, inasinuch as the yield of acetic acid and wood spirit would be
diminished. For this reason, it is advantageous to provide on the outlet tube of
the coudensing apparatus, an alarm device which is set in motion directly the oil
censes to flow.
When the extraction of the turpentine is concluded, the steam is turned off and
the usual process of distillation is begun.
The forcing in of steam has absolutely no injurious effect on the subsequent
distillation, because with the contents of the retort at a temperature of 120° no
condensation of the steam is possible, and the briquettes, in this heated condition,
do not absorb water.
It has been ascertained, through numerous analyses, that the yield of the other
products of distillation, especially of acetic acid and pyroxylic spirit, suffers no
loss in consequence of the previous extraction of the turpentine.
The introduction of the new process before the actual distillation of the wood
thus constitutes a considerable technical advance, as it thereby becomes possible
to obtain another important product, riz. turpentine, from the wood, without
injuring the yield of the other products of distillation.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what mauner the same is to bo performed, I declare that what I
claim is :-
1. The improved process for obtaining turnentine from wood and wand

page_text: (preferably in the form of briquettes) which consists in heating the same in retorts
passing a current of dry steam, at about 120° C., through such retorts, and,
condensing the turpentine, carried off by the steam, in suitable apparatus,
substantially as described.
2. The improved process for obtaining turpentine from wood and wood waste,
forming a preliminary step to the destructive distillation of the latter, substantially
as hereinbefore described."
Dated this 18th day of November 1896.
ERNEST DE PASS,
Chartered Patent Agent,
78, Fleet Street, London, and 54 Market Street, Nottingham,
Agent for the Applicant.