AN IMPROVEMENT IN PURIFYING COAL GAS
Year: 1856

page_text: LETTERS PATENT to William Marriott and David Sugden, of Hudders-
field, in the County of York, Agricultural and Manufacturing Chemists,
for the Invention of "AN IMPROVEMENT IN PURIFYING COAL GAS."
Sealed the 31st March 1857, and dated the 7th October 1856.
PROVISIONAL SPECIFICATION left by the said William Marriott and
David Sugden at the Office of the Commissioners of Patents, with their
Petition, on the 7th October 1856.
We, WILLIAM MARRIOTT and DAVID SUGDEN, of Huddersfield, in the County
of York, Agricultural and Manufacturing Chemists, do hereby declare the
nature of the Invention for "AN IMPROVEMENT IN PURIFYING COAL GAS," to be
as follows:-
This Invention has for its object an improvement in purifying coal gas.
Heretofore in some cases sulphuric acid in the fluid state has been employed
for such purpose, and the purification of the gas has been accomplished by
passing the gas up through a quantity of the acid, the gas having to overcome
the pressure of the column of fluid acid, through which it has had to force
its way.
Now, our improvement consists in employing sulphuric acid by what may
be called the dry process, by combining sawdust, or other vegetable fibrous
matter, or shoddy, or like animal matter, with the sulphuric acid, which
matters becoming charred by the acid produce a compound of sulphuric acid,

page_text: and such charred matters, suitable for being used in dry gas purifiers, present-
ing a large extent of surface of the acid to the gas, and offering considerably
and such charred matters, suitable for being used in dry gas purifiers, present-
ing a large extent of surface of the acid to the gas, and offering considerably
Tess resistance to the gas in its passage amongst such surfaces. The matters
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Marriott and David Sugden in the Great Seal
Patent Office on the 2nd April 1857.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, WILLIAM
MARRIOTT and DAVID SUGDEN, of Huddersfield, in the County of York,
Agricultural and Manufacturing Chemists, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Seventh day of October, in the year of our Lord
One thousand eight hundred and fifty-six, in the twentieth year of Her reign;
did, for Herself, Her heirs and successors, give and grant unto us, the said
William Marriott and David Sugden, Her special licence that we, the said
William Marriott and David Sugden, our executors, administrators, and
assigns, or such others as we, the said William Marriott and David Sugden,
our 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, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "AN IMPROVEMENT IN PURIFYING
COAL GAS," upon the condition (amongst others) that we, the said William
Marriott and David Sugden, our executors or administrators, by an instrument
in writing under our or their hands and seals, or under the hand and seal of
one of us or them, 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 William Marriott, on behalf of myself
and the said David Sugden, do hereby declare the nature of the said Inven-
tion, and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement thereof, that is
to say:
This Invention has for its object an improvement in purifying coal gas.
Heretofore in some cases sulphuric acid in the fluid state has been employed

page_text: for such purpose, and the purification of the gas has been accomplished by
passing the gas up through a quantity of the acid, the gas having to overcome
the pressure of the column of fluid acid through which it has had to force
its way.
Now, our improvement consists in employing sulphuric acid by what may
be called the dry process, by combining sawdust, or other vegetable fibrous
matter, or shoddy, or like animal matter, with the sulphuric acid, which
matters becoming charred by the acid produce a compound of sulphuric acid,
and such charred matters, suitable for being used in dry gas purifiers, present-
ing a large extent of surface of the acid to the gas, and offering considerably
less resistance to the gas in its passage amongst such surfaces. The matters
thus used for purifying gas are after such use very suitable for manure.
Having thus stated the nature of our said Invention, we will proceed more
fully to describe the manner of performing the same.
The object of the Invention is to separate the ammonia from gas by the
application of sulphuric acid combined with wood, or vegetable, or animal
fibre combined, in order that the acid may be used in what are called dry
gas purifiers.
In carrying out the Invention it is preferred to employ wood sawdust
combined with sulphuric acid, and in practice we have found that the acid is
most advantageously employed when at a specific gravity of 1.425. We do
not, however, confine our Invention to the use of that strength. The sawdust or
other woody or vegetable or animal fibre in the dry state is first combined with
the acid, and for each hundredweight of dry wood sawdust we apply about
168 lbs. of acid of the strength above mentioned, but we do not confine our-
selves to these proportions, and when the same have been well and intimately
mixed it is exposed to a heat of about 250° Fahrenheit, in a stove or other-
wise, until the woody or vegetable or animal fibre is thoroughly carbonised,
and the sulphuric acid absorbed by the carbon; thus formed in this state it is a
light and dry porous matter, and offers no obstruction to the passage of the
gas. We apply the compound on the shelves of ordinary dry gas purifiers in
the same manner as other materials are used in such descriptions of purifiers;
we, however, first spread on the shelves a quantity of those materials which
have been previously used, and which are well saturated, in order to prevent
the fresh materials coming in contact with the shelves, so as to injure them
by the action of the acid, and on such layer on each shelf we spread over
two or three inches of the fresh materials. In order to ascertain whether the
gas is thoroughly freed from ammonia, we from time to time test it with
turmeric paper, which will be turned to a reddish color if there be ammonia

page_text: present; but will remain unchanged when the gas has been purified from
ammonia. Other fibrous vegetable or animal matters may be used in a similar
manner with the sulphuric acid, but, as before stated, it is preferred to employ
wood sawdust.
Having thus described the nature of our said Invention and the manner of
performing the same, we would have it understood that what we claim is, the
application of sulphuric acid in dry gas purifiers, first combining the acid
with wood or other vegetable fibre or with animal fibre so as to thoroughly
carbonise the same.
In witness whereof, I, the said William Marriott, have hereunto set my
hand and seal, this Thirty-first day of March, in the year of our
Lord One thousand eight hundred and fifty-seven.
Witness,
JNO. ALCOCK.
WILLIAM MARRIOTT. (L.S.)