IMPROVEMENTS IN REBURNING ANIMAL CHARCOAL, AND IN THE APPLICATION OF THE PRODUCTS ARISING THEREFROM, AND IN THE APPARATUS EMPLOYED THEREIN."
Year: 1860

page_text: LETTERS PATENT to James Duncan, and Alexander Scott, both of
Greenock, in the County of Renfrew, North Britain, Sugar Refiners,
and James Dawson, of the same Place, Manager, for the Invention of
"IMPROVEMENTS IN REBURNING ANIMAL CHARCOAL, AND IN THE APPLICATION OF
THE PRODUCTS ARISING THEREFROM, AND IN THE APPARATUS EMPLOYED THEREIN."
PROVISIONAL SPECIFICATION left by the said James Duncan, Alexander
Scott, and James Dawson, at the Office of the Commissioners of Patents,
with their Petition, on the 27th January 1860.
We, JAMES DUNCAN and ALEXANDER SCOTT, both of Greenock, in the
County of Renfrew, North Britain, Sugar Refiners, and JAMES DAWSON, of
the same Place, Manager, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN REBURNING ANIMAL CHARCOAL, AND IN THE APPLICATION OF
THE PRODUCTS ARISING THEREPROM, AND IN THE APPARATUS EMPLOYED THEREIN," to
be as follows:-
This Invention relates to the treatment and reburning of animal charcoal or
carbonaceous matter, such as is used in. the refining of sugar and in other
chemical processes, according to a system which allows of the free escape of
the gaseous products arising from the combustion, as well as of the commer-

page_text: cially valuable adaptation of such products. In carrying out this Invention
in practice each retort or vertical chamber in which the spent or contaminated
animal charcoal is reburnt after use, is fitted with a vertical tube of metal or
other material passed down its whole length. This tube is perforated laterally
for the purpose of enabling the gaseous products of combustion to escape from
the burning mass of charcoal or carbonaceous matter into the interior of the
tube and thence escape into the atmosphere by the open upper end of the
tube. This free escape of the gases, secures a superior quality of the reburnt
carboneous matter, the charcoal is better burnt and a great saving of time is
effected in the operation. Instead of simply allowing the gases to flow off, a
fan pump or other apparatus may be fitted up so as to thoroughly exhaust
them; when so taken off or exhausted, the discharge gases are available for
economical use in the manufacture of sulphate of ammonia, and other chemical
products. The charcoal reburnt in this way, or by this additional aid, is
very superior in quality to that treated in the ordinary manner, and it is
peculiarly serviceable in deodorising and decolorising beet-root sugar.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said James Duncan, Alexander Scott, and James Dawson, in
the Great Seal Patent Office on the 27th July 1860.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, JAMES
DUNCAN and ALEXANDER SCOTT, both of Greenock, in the County of Renfrew,
North Britain, Sugar Refiners, and JAMES DAWSON, of the same Place,
Manager, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the .Twenty-seventh day of January in the year of our
Lord One thousand eight hundred and sixty, in the twenty-third year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
us, the said James Duncan, Alexander Scott, and James Dawson, Her special
license, that we, the said James Duncan, Alexander Scott, and James Dawson,
our executors, administrators, and assigns, or such others as we, the
said James Duncan, Alexander Scott, and James Dawson, our executors,
administrators, or 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 lawfully 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 REBURNING ANIMAL

page_text: CHARCOAL, AND IN THE APPLICATION OF THE PRODUCTS ARISING THEREFROM AND IN
THE APPARATUS EMPLOYED THEREIN," upon the condition (amongst others) that
we, the said James Duncan, Alexander Scott, and James Dawson, by an
instrument in writing under our hands and seals, 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 we, the said James Duncan, Alexander Scott, and
James Dawson, do hereby declare the nature of our said Invention, and
in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement, that is to say.
Our said Invention relates to the treatment and re-burning of animal
charcoal, or what is generally known as ivory or bone black, or the car-
bonaceous matter which is ordinarily used in the refining of sugar, and in
other chemical processes.
The object of our improvements is to treat the used animal charcoal in such
manner as to admit of the free escape of the gaseous products arising from the
re-calcination, and also to utilize these products, so as to economise the con-
sumption of fuel, or apply them to the manufacture of other chemical
products. In carrying this Invention out in practice, it is preferred to use for
the purpose a range or series of retorts, or chambers for holding the used
charcoal. These retorts are arranged in sets or "benches" of three, five, or
other convenient number of retorts, and they are arranged in a vertical or
horizontal position. The retorts are arranged in brickwork in the ordinary
manner, and heated in the usual way by means of furnaces. These retorts,
when they are disposed vertically, are left open at the upper part for the
purpose of charging the retort with the spent or used charcoal.
Each retort
bás fitted to it a pipe which is carried downwards into the retort, and termi-
nates at or near the bottom. That part of the pipe which is enclosed within
the retort has formed in.it a great number of holes which pass through the
metal in a lateral direction. The upper portion of the pipe is extended so as
to admit of its being carried into the shaft or chimney connected with the
furnaces, or it is caused to communicate with other means for exhausting or
drawing off the gaseous products. The whole number of retorts employed in
the work are fitted in like manner to the example we have just described.
The animal charcoal which is to be treated according to these improvements,
is first washed in water to free it from the saccharine matter held in contact
with it. The retorts are charged with the impure charcoal, and the heat of

page_text: the furnaces is raised, so as to bring the retorts and their contents to a bright
red heat. During this calcination the animal charcoal contained in the retorts
gives off a large quantity of gaseous matters, which under the ordinary process
of revivification do not properly escape from the burning mass, and conse-
quently the purity of the resulting product is injured.
According to our mode of treatment, these gaseous products pass off
through the perforations in the central pipe, and are conveyed away to the
chimney. If the natural draft of the shaft or chimney is not sufficient to.
draw off the gaseous products with the requisite velocity, a fan wheel or air
pump is arranged so as to communicate with the chamber or reservoir into
which the extremities of the perforated pipes are brought. Upon this fan or
pump being put in motion, the gaseous products are drawn off as quickly as
they are evolved from the burning charcoal, a gauze wire diaphragm or
other suitable medium being interposed at a convenient part of each. "pipe to
prevent any portion of the solid particles from being withdrawn by the action
of the exhausting apparatus.
i
In the case of retorts arranged horizontally, the gas tube is preferred to be
disposed nearer to the upper part of the retort, and to pass out at the back-
ward end of the retort, or other suitable part, and away to the chimney or.
exhausting apparatus.
In some cases it may be preferred to have two or other convenient number
of pipes passing through the charcoal; the diameter of the pipe or pipes being
suited to the quantity of charcoal operated upon in each chamber or retort..
The gaseous products so obtained may be utilized by conveying them into the
furnace, and being there consumed they assist in heating the retorts, and so
economise the consumption of the fuel. Or, in lieu of this mode of disposing of
the gaseous matters, they may be applied to the manufacture of sulphate of
ammonia, and other generally similar chemical products.
Having now described and particularly ascertained the nature of our said
Invention, and the manner in which the same is or may be used or
carried into effect, we would observe in conclusion, that what we consider.
novel and original, and therefore claim as the Invention secured to us by the
herein-before. in part recited Letters Patent, is;-
First, the system or mode of treating or re-burning animal, charcoal with
the aid of the mechanical arrangement for withdrawing the. gaseous, matters,
as herein-before described.
Second, the application to and use in apparatus for re-burning animal
charcoal, of a tube or tubes for carrying away the gaseous products evolved
from the used charcoal, as herein-before described.

page_text: Third, the system or mode of collecting the gaseous matters evolved in
re-burning animal charcoal, and utilizing the same either by causing them to
assist in heating the retorts, or applying them to aid in the production of
chemical products, as berein-before described.
In witness whereof, we, the said James Duncan, Alexander Scott, and
James Dawson, have hereunto set our hands and seals, this Twenty-
fifth day of July, One thousand eight hundred and sixty.
JAMES DUNCAN.
(L.S.)
ALEXANDER SCOTT. (L.S.)
JAMES DAWSON.
(L.S.)