IMPROVEMENTS IN THE PURIFICATION OF COAL GAS
Year: 1872

page_text: ·LETTERS PATENT to Henry Young Darracott Scott, of Ealing, in
the County of Middlesex, Major-General, C.B., for the Invention
of "IMPROVEMENTS IN THE PURIFICATION OF COAL GAS."
Sealed the 28th June 1872, and dated the 4th January 1872.
PROVISIONAL SPECIFICATION left by the said Henry Young
Darracott Scott at the Office of the Commissioners of Patents,
with his Petition, on the 4th January 1872.
I, HENRY YOUNG DARRACOTT SCOTT, of Ealing, in the County of
Middlesex, Major-General, C.B., do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN THE PURIFICATION OF COAL GAS," to be
as follows:-
The object of this Invention is the removal of sulphur from coal gas
in a cheap and efficient manner.
In carrying out my Invention I take quicklime, and having heated
it to redness in a suitable conduit or chamber I pass the gas to be
purified over it. The heated lime will abstract the sulphur or sulphur

page_text: compounds from the gas, and I thus get rid of the sulphur existing in
the gas, which comes away from the lime comparatively pure so far as
regards sulphur. The new sulphur compounds thus obtained may be
used for any of the purposes for which they may be applicable in
the arts.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Henry Young Darracott Scott in the Great Scal
Patent Office on the 4th July 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
YOUNG DARRACOTT SCOTT, of Ealing, in the County of Middlesex,
Major-General, C.B., send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fourth day of January, in the year
of our Lord One thousand eight hundred and seventy-two, in the thirty-
fifth year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said Henry Young Darracott Scott, Her special licence
that I, the said Henry Young Darracott Scott, my executors, adminis-
trators, and assigns, or such others as I, the said Henry Young Darracott
Scott, 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 lawfully might make,
use, excrcise, and vend, within the United Kingdom of Great Britain
and Ireland, the Channel Islands, and Isle of Man, an Invention
for "IMPROVEMENTS IN THE PURIFICATION OF COAL GAS," upon the con-
dition (amongst others) that I, the said Henry Young Darracott Scott,
my executors or administrators, by an instrument in writing under my,
or their, or one of their hands and scals, 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 immo-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Henry Young Darracott Scott, do
honaly declare the nature of my said Invention and in what manner

page_text: the same is to be performed, to be particularly described and ascertained
in and by the following statement, (that is to say) :—
The object of this Invention is the removal of sulphur from coal gas
in a cheap and efficient manner. To this end I take quicklime, and
having heated it to redness in a suitable conduit or chamber I pass the
gas as it comes from the condenser through the improved purifier. I
find that the most suitable temperatures for heating the quicklime for
the purpose are those varying between a redness just visible in the dark
and a low red heat, and that the most convenient form in which the
lime can be used is in small pieces of the size of a hazel nut. The
object I have in view is to promote the ready permeation of the mass of
lime by the gas, and the exposure of a large surface of the purifying
material so that the whole body of gas may be thoroughly acted upon.
The chamber or conduit containing the lime may be heated in any
convenient manner by means of a furnace, the flames of which will play
around the chamber containing the quicklime, which may be arranged
either upon shelves or simply be placed loosely in the chamber. The
heated lime will then react on the sulphur compounds contained in the
gas and will cause their decomposition, the sulphur being retained in
combination with the lime. The gas then passes away from the limo
comparatively pure as regards freedom from sulphur.
Although the above-named temperatures are found to be the most
suitable, I do not intend to confine myself to them, as the lime may bo
used either at an increased or decreased temperature without any great
sacrifice of efficiency in the process. Neither do I intend to confine
myself to the particular mechanical condition of the quicklime as above
specified, nor to any particular form or arrangement of chamber in
which the lime is heated.
Having now described my improved process for the purification of
coal gas, and having explained the manner of carrying the same into
effect, I would observe that I am aware lime in the hydrated condition
has been applied to the purification of gas from sulphur with the aid of
a low heat; I wish it therefore to be clearly understood that this mode
of using lime for the purification of coal gas forms no part of my process,
but that which I consider to be new and the Invention which I desire
to secure by Letters Patent as aforesaid is, the use of quick or anhydrous

page_text: lime in a heated state for depriving coal gas of its sulphur as hercin set
forth.
In witness whereof, I, the said Henry Young Darracott Scott,
have hereunto set my hand and seal, the Third day of July,
in the year of our Lord One thousand eight hundred and seventy- &
two.