IMPROVEMENTS IN THE DISTILLATION OF TURPENTINE AND OTHER RESINOUR SUBSTANCES AND THEIR PRODUCTS
Year: 1853

page_text: LETTERS PATENT to Thomas William Keates, of Chatham Place,
Blackfriars, in the City of London, Chemist, for the Invention of
"IMPROVEMENTS IN THE DISTILLATION OF TURPENTINE AND OTHER
RESINOUR SUBSTANCES AND THEIR PRODUCTS."
Sealed the 11th March 1854, and dated the 15th September 1858.
PROVISIONAL SPECIFICATION left by the said Thomas William
Keates at the Office of the Commissioners of Patents, with his
Petition, on the 15th September 1853.
I, THOMAS WILLIAM KEATES, do hereby declare the nature of the
5 said Invention for "IMPROVEMENTS IN THE DISTILLATION OF TURPENTINE
AND OTHER RESINOUS SUBSTANCES AND THEIR PRODUCTS" to be as follows:-
The principle of this Invention consists in employing common or low
pressure steam, and superheated steam or heated air for the separation
of the volatile essential oil or spirituous portion of turpentine- and
resinous substances of a similar character from the fixed portion, or as
it is commonly called the rosin.
To effect this object the patentee proposes to blow into a still contain-
ing the crude turpentine or other matter to be distilled a current of steam
at a pressure of about three or four lbs. on the inch, more or less, by

page_text: means of a coil of iron or copper pipe perforated with holes to permit of
the steam permeating and blowing through the mass in the still. By this
means the whole of the volatile matters will be expelled, and the rosin
left entirely deprived of the essential oil or spirit. But the rosin so
produced is opaque and cloudy, and unfit for the purpose of commerce.
When therefore the volatile matter has been extracted by the action of
the common steam, superheated steam or heated air must be blown
through the rosin in the place of the common steam. By this means
the rosin will be rendered perfectly bright and clear, of a very superior
quality, and quite fit for the market.
The advantages of the new process over that employed at present
are,-
The avoidance of the use of open fires, and the consequent total
absence of danger from fire in the event of the bursting of stills or
any other accident by which the contents of the still should be suddenly
poured out.
The absence of any wear or tear of the still itself from the effect of
high temperature or from sudden changes of temperature, the latter
never exceeding in the new process 250° or 260° Fahr.
The perfect control which can be maintained over the temperature of
the contents of the still, as the temperature of the steam or hot air
can be exactly regulated before entering the still by a method pro-
posed by the patentee.
The production of a better quantity of rosin, which in this process
is not subject to be charred or colored by an excessive temperature,
a result which cannot be avoided in the means employed at the present
time.
Lastly, the great saving of expense which must accrue from the
substitution of one boiler fire for the several furnace fires now used, an
advantage which will be increased by the circumstance that the
preliminary process of melting the turpentine, instead of remaining a
separate process as at present, will become part of the steam operations,
and will be effected by the same boiler and fire as the distillation
itself.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Thomas William Keates in the Great Seal Patent
Office on the 15th March 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I,
THOMAS WILLIAM KEATES, of Chatham Place, Blackfriars, in the City
of London, Chemist, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fifteenth day of September, in the
year of our Lord One thousand eight hundred and fifty-three, in the
seventeenth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Thomas William Keates,
Her special license that I, the said Thomas William Keates, my
executors, administrators, and assigns, or such others as I, the said
Thomas William Keates, my executors, administrators, and assigns,,
should at any time agree with, and no others, from time to time and at
all times thereafter during the term therein expressed, should and law-
fully might make, use, exercise, and vend, within the United Kingdom.
of Great Britain and Ireland, the Channel Islands, and Isle of Man,
an Invention for "IMPROVEMENTS IN THE DISTILLATION OF TURPENTINE AND
OTHER RESINOUS SUBSTANCES AND THEIR PRODUCTS," upon the condition
(amongst others) that I, the said Thomas William Keates, by an
instrument in writing under my hand and scal, should particularly
describe and ascertain the nature of the said Invention, and in what
manner the same was to be performed, and cause the same to be filed
in the Great Seal Patent Office within six calendar months next and
immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Thomas William Keates, do
hereby declare the nature of my said Invention, and in what manner
the same is to be performed, to be particularly described and ascer
tained in and by the following statement, reference being had to the.
Drawing hereunto annexed, and to the letters and figures marked
thereon (that is to say):
My Invention of improvements in the distillation of turpentine
and other resinous substances and their products has for one of its
principal objects to obviate the necessity of employing a furnace or

page_text: open fire in these processes as is now the case, and in place thereof to
make use of steam or heated air, the former being superheated, and
used either alone or in combination with common steam.
The first part of my Invention relates to the use of steam alone in
the distillation of turpentine or other resinous matter.
The second part of the Invention relates to the use of heated air as
the medium of communicating heat to the crude turpentine or other
resinous matter.
In my method of distilling by steam I make use of what I term free
steam, (that is to say,) I allow steam superheated to the proper
temperature, or modified by admixture with common steam, to escape
into a still through a coil of pipe perforated with holes, and arranged near
the bottom or other part of the still, and leading from the steam boiler..
By this arrangement the steam is allowed to blow through the contents
of the still, and by acting upon the resinous material will carry off.
therefrom the volatile essential oil or spirit, which, with the steam, is
conducted into a refrigerator or worm, and there condensed in the
usual manner.
By continuing to pass the steam through the turpentine or other
resinous matter for a sufficient time the essential oil or spirit will be
driven off, and the residue will consist of rosin. The rosin is, however,
at first opaque, whereas for the purposes of commerce it is necessary
that it should be quite transparent. The clearing of the rosin in the
usual process of manufacture is effected by the continued application of
heat by means of an open fire. Now according to my Invention I
make the steam effect this object. The clarification of the rosin cannot,
however, be effected by common steam, as when free common steam is
used it is impossible to obtain a higher temperature in the still than
two hundred and twelve degrees Fahrenheit or thereabouts, at which
temperature the excess of water cannot be expelled from the resinous
residue of the distillation, and therefore the clarification cannot be
effected.
In order to make the steam effective in clearing the rosin I apply it
in what I have already spoken of as a superheated state, and it is
brought to this state by passing it, as it leaves the boiler, through a
pipe or coil of pipe arranged either in the flues of the boiler furnace,

page_text: or in a furnace constructed for this especial purpose. This pipe may
be heated to any required temperature up to a red heat, and the steam
as it passes through the pipe of course acquires a temperature almost
equal to that of the pipe itself. When the steam is passed into the
rosin in this superheated state it carries off the watery particles, and
causes the rosin to become perfectly clear and bright. I do not con-
sider that the temperature to which the steam is to be superheated is a
point of much importance with reference to the mere clearing of the
rosin, provided it be sufficient to produce the required effect; but with
respect to the quality and color of the rosin so obtained it is desirable
that the steam should be used at as low a temperature as is consistent
with its effective operation.
I have already said that sometimes I use common steam in com-
bination with superheated, I therefore propose to arrange the apparatus
in the following manner. In conducting the steam into the still I
employ two pipes, one leading directly from the boiler and conveying
common steam, the other also leading from the boiler, but passing
through a furnace where it is arranged in a pipe or coil in which the
steam is superheated previous to its being conveyed to the still. These
two pipes should be made to unite just before they enter the still, and
each should be supplied with a cock, by which arrangement either
common steam alone, or superheated steam alone, or the two combined
in any proportion, may be admitted into the still, and the temperature
of the steam employed in the distillation may be exactly regulated by
placing a thermometer in the pipe in which the pipes conducting the
common and superheated steam respectively unite.
In the accompanying Drawing I. have shewn an elevation of an
apparatus constructed upon this principle. a, a, is the still, mounted
on a suitable foundation, and surrounded with a casing or envelope
provided with any bad conductor of heat, so as to prevent radiation
from the still as much as possible. b, b, is the still head. c, the cock
or exit aperture, from which the liquid residuum or rosin is run out
after the process is completed. d, is a steam pipe conveying common
steam from a boiler. e, is another pipe conveying superheated steam
which bas been heated in pipes in a furnace not shewn in the Drawing.

page_text: These pipes d, and e, are connected to a common pipe f, which is pro-
vided with a thermometer g, to indicate the temperature of the steam
that passes through it. Each of the pipes d, and e, is provided with a
cock h, and i, for the purpose of opening or closing the communica-
tion, as before mentioned.
It is not positively necessary to employ superheated steam in the
beginning of the distillation (that is, not until the essential oil is all
expelled). Up to that point common steam may be blown through the
resinous matters, but for the removal of the opacity and cloudiness of
the rosin it is essential that the steam should be superheated to a tem-
perature considerably above two hundred and twelve degrees. It is,
however, better to employ the superheated steam from the first, and to
regulate its temperature so that, until the whole of the essential oil is
expelled from the rosin, the temperature of the steam as it is blown
into the rosin shall not exceed two hundred and twenty degrees or
two hundred and twenty-five degrees Fahrenheit; whereas, after the
volatile oil is distilled off, the temperature of the steam for clearing
the rosin must not be much less than two hundred and fifty degrees
Fahrenheit.
With reference to the first part of my Invention, I claim the use
of superheated steam, either alone or in combination with common
steam, in the distillation of turpentine and other resinous substances,
and in clearing the rosin so as to bring it into a marketable state, as
above described.
The second part of my Invention relates to the employment of heated
air as a substitute for steam in the distillation of turpentine and other
resinous matters as described above. When air is employed I merely
force it by means of a force pump worked in the usual manner
through a pipe or coil of pipes, arranged in a furnace or otherwise,
and heated up to a red heat or other requisite temperature, as in
the case of the superheated steam. The air heated by its passage
through this pipe is applied to the distillation of turpentine and other
resinous substances, and the clearing of the rosin, exactly in the
manner already. described in reference to steam, and by means of
similar apparatus in either case; and being allowed to escape from a

page_text: perforated pipe, and blow through the contents of the still, as in the
process already described, it will be found that the heated air will
operate precisely in the same manner, and produce upon the turpentine
and rosin the same effect, as the superheated steam.
I sometimes propose to use steam and hot air in combination, in
which case I employ steam for the first part of the distillation process,
that is, for the separation of the volatile essential oil or spirit from the
rosin or solid matters, and then I make use of heated air for the pur-
pose of clearing or clarifying the rosin, as already described.
In the second part of my Invention what I claim is, the use of
heated air as a source of heat applied through the medium of any
convenient apparatus in the distillation of turpentine or other resinous
matters, and in the place of and as a substitute for the furnace and open
fire as at present employed.
In witness whereof, I, the said Thomas William Keates, have
hereunto set my hand and seal, the Fifteenth day of March,
in the year of our Lord One thousand eight hundred and fifty-
four
0 Witness,
J. W. MOFFATT,
66, Chancery Lane.
T. W. KEATES. (L.S.)