IMPROVEMENTS IN THE MODE OF EXTRACTING AMMONIA, PURIFYING GAS LIQUOR, AND UTILISING THE SAME
Year: 1869

page_text: LETTERS PATENT to Alexander Rollason, of No. 123, Pembroke Road,
in the Parish of Clifton, in the City and County of Bristol, Chemist,
for the Invention of "IMPROVEMENTS IN THE MODE OF EXTRACTING
AMMONIA, PURIFYING GAS LIQUOR, AND UTILISING THE SAME."
Sealed the 7th January 1870, and dated the 16th July 1869.
PROVISIONAL SPECIFICATION left by the said Alexander Rollason at
the Office of the Commissioners of Patents, with his Petition, on
the 16th July 1869.
I, ALEXANDER ROLLASON, of No. 123, Pembroke Road, in the Parish
of Clifton, in the City and County of Bristol, Chemist, do hereby declare
the nature of the said Invention for "IMPROVEMENTS IN THE MODE OF
EXTRACTING AMMONIA, PURIFYING GAS LIQUOR, AND UTILISING THE SAME," to
be as follows:-
I take ordinary gas liquor (ammoniacal liquor), and placing it in a
suitable closed vessel I subject it to heat either by means of a fire-
box, a steam chamber, or steam pipes, or I inject steam into it to obtain
the necessary heat, which may be raised to 212° Fahrenheit. There may
be put into the liquor hydrated lime, oxide, and sulphate of iron, or
any other of the purifying substances used by gas makers and capable

page_text: of removing sulphureted hydrogen, which substances also by the
application of heat would assist in eliminating ammonia from the
said liquor. If lime only be used in the boiling, and after boiling the
liquor is no longer acted upon by acid, I purify this residual liquor by
adding reagents, such as sulphate of iron, until no more precipitate is
thrown down. After settling down, the clear liquor is quite free from
disagreeable odour or injurious properties, and may be used as ordinary
water in gasworks or thrown away as sewage, and the precipitate is
available as a pigment. 'If oxide or sulphate of iron be used in the
boiling it would require from 2 lbs. to 20 lbs. for 20 gals. according to
the strength of the liquor; these would be precipitated spontaneously,
being available as pigments, while the clear liquor being also inodourous
would be used in the works or thrown away. The ammonia which
would arise from the liquor would be taken up or neutralized by
preparations which I make for purifying coal gas, and for which I
obtained Letters Patent, August 1868, No. 2598. Although I use
similar preparations made of sawdust, spent tan, shoddy, and such
like materials mixed with sulphuric acid in the same proportions as
named in said Patent of August 1868, No. 2508, which preparations
are placed on trays like lime in a gas purifying box, or they might be
placed in a revolving cylinder, which trays or cylinder would be either
immediately over the boiling liquor, or by suitable well-known arrange-
ments apart from it; care of course being taken that by water or other
suitable luting none of the ammonia as it rises from the boiling liquor
is allowed to escape.
Or in place of using any of the foregoing absorbents I use acids
(sulphuric or hydrochloric) simply, which would either be highly con-
centrated or diluted as required, and which would be placed on leaden
trays or shelves, and also enclosed in a gas-proof chamber.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Alexander Rollason in the Great Seal Patent Office
on the 15th January 1870.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
ROLLASON, of. No. 123, Pembroke Road, in the Parish of Clifton, in the
City and County of Bristol, Chemist, send greeting..

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date, the Sixteenth day of July, in the year of
our Lord One thousand eight hundred and sixty-nine, in the thirty-third
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said Alexander Rollason, Her special licence that I,
the said Alexander Rollason, my executors, administrators, and assigns,
or such others as I, the said Alexander Rollason, my exccutors,
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 "IMPROVEMENTS IN
THE MODE OF EXTRACTING AMMONIA, PURIFYING GAS LIQUOR, AND UTILISING THE
SAME," upon the condition (amongst others) that I, the said Alexander
Rollason, my executors or administrators, by an instrument in writing
under my, or their, or one of their 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 I, the said Alexander Rollason, do hereby
declare the nature of my said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement:-
The object of my Invention is to extract from ammoniacal gas liquor.
the ammonia contained therein and cause the latter to combine with
acids or other substances, so that it may be employed. for manure or
various other useful purposes. To this end I take ordinary gas liquor
(ammoniacal liquor) and place it in a suitable closed vessel, in which
it is subjected to heat either by means of a fire-box, a steam chamber,
or steam pipes, or I inject steam into it to obtain the necessary heat,
which may be raised to 212° Fahrenheit. There may be put into the
liquor hydrated lime, oxide and sulphate of iron, or any other of the
purifying substances used by gas makers for removing sulphuretted
hydrogen. These substances by the application of heat would also
assist in eliminating the ammonia from the gas liquor. If lime only
be used in the boiling or heating, and if after boiling the liquor is no
longer acted upon by acid I purify this residual liquor by adding

page_text: reagents, such as sulphate of iron, until no more precipitate is thrown
down. After settling down the clear liquor will be quite free from
disagreeable odour or injurious properties, and may be used as ordinary
water in gasworks, or it may be thrown away as sewage, and the
precipitate will be available as a pigment. If oxide or sulphate of iron
be used in the boiling it would require from 2 lbs. to 20 lbs. for 20
gallons according to the strength of the liquor. The iron compounds
would be precipitated spontaneously and be available as pigments, while
the clear liquor being also inodorous would be used in the works or
thrown away. The ammonia which would arise from the liquor will
be taken up or neutralized by preparations which I make for purifying
coal gas, and for which I obtained Letters Patent, August 1868, No.
2598. I use preparations made of sawdust, spent tan, shoddy, and such
like materials mixed with sulphuric acid in the same proportions as
named in said Patent of August 1868, No. 2598, which preparations are
placed on trays like lime in a gas purifying box, or they may be placed
in a revolving cylinder. These trays or cylinder may be either imme-
diately over the boiling liquor, or they may be arranged apart from
it; care of course being taken that by water or other suitable luting
none of the ammonia as it rises from the boiling liquor be allowed to
escape.
Or in place of using any of the foregoing absorbents I use acids
(sulphuric or hydrochlorie) simply, which would either be highly
concentrated or diluted as required, and which would be placed on
leaden or other trays or shelves, and also enclosed in a gas-proof chamber
which would be capable of resisting internal pressure.
In carrying out my Invention I employ a vessel made of iron or other
suitable material and of any convenient capacity, such as that shewn in
the accompanying Drawing, in which Fig. 1 is a longitudinal vertical
section, and Fig. 2 a transverse section of my improved apparatus com-
plete. In this vessel a I place the ammoniacal gas liquor, which I prefer
to heat by a steam chest or by pipes, as at b, b, in the Drawing, whereby
it may be raised to the boiling point if desired. The ammonia (NH)
which rises from the heated liquor in the vessel a may be made to pass
through quicklime placed on trays in the upper part of the vessel, but not
shewn in the Drawing. Instead of time, or in combination therewith,
a preparation of iron similar to those which are now used at gasworks
for purifying gas may be employed. The object of using quicklime

page_text: is to absorb the water or steam which would rise with the ammonia,
and also to assist in otherwise purifying the ammonia from foreign
products, such as carbonic acid and sulphuretted hydrogen, which rise
with it. The iron preparation also has an analogous use. It is not
absolutely necessary that the ammonia should be made to pass through
these purifying materials, the only difference being that if it did not
the resulting product of the combination of the ammonia with the
acids in the chamber above would be less pure. The ammonia on being
evolved from the liquor in the chamber a by boiling passes up through
the bent pipe c into a gas-proof chamber d, which I prefer to place
immediately over the liquor chamber a. The ammonia on entering
the chamber d is brought in contact with sulphuric or hydrochloric acid
or preparations consisting of dry sawdust or peat saturated with a large
quantity of acids, say 6 lbs. of oil of vitriol to 1 lb. of sawdust or
superphosphate of lime and such like material saturated with sulphuric
acid. These acids or preparations are placed upon leaden or other
In this case
suitable trays, which may rest on the ledges e, e, Fig. 2.
the ammonia is not driven into or through the acids or acid preparations;
but floats about until it becomes spontaneously absorbed by them. The
upper chamber d containing the trays of acids would have to be made
strong enough to resist considerable internal pressure, and is provided
with an opening fat one end to enable the workman to place in the
trays, take them out, and remove any salts that may have crystallized
therein. This opening must of course be properly secured gas-tight
before the operation is commenced. A safety valve or pipe g would
have to be placed also on this chamber to indicate and relieve any
undue pressure.
At the bottom part of the upper chamber is a steam
chest or pipes h, h, through which the steam might pass previous to
its passing to the lower chamber a in which the liquor lies, and upon
this steam chest there is a leaden or other tray i on which the resulting
product of the combination of the ammonia with the acid might if
necessary be dried. When I use acids mixed with other substances,.
such as sawdust, spent tan, or pulverized peat or superphosphate of lime
or other such like material as before mentioned, I find that such mixtures
may be placed upon trays in the same way as the ordinary purifying
materials at gasworks, and that the ammonia which rises from the
boiling liquor may be forced through the granular or comminated
substance, and so become absorbed thereby. When it is found that all
the available ammonia has been got out of the liquor the latter may

page_text: be drawn off and used in the gasworks in lieu of water, or otherwise
disposed of. If preferred the ammonia gas from the pipe c may be
first made to bubble up in liquid acid placed in the tray i, and any
ammonia that escapes uncombined will float about in the chamber d
until it is taken up by the chemical substances on the trays above.
I find also considerable advantage in using about 1 cwt. of slaked
lime to 500 gallons of liquor in the vessel a, as the ammonia is
disengaged much faster from the liquor, but it would be desirable in
this case to use stirrers or agitators such as those shewn at j, j, which
may be worked to and fro by the handles j, j, outside. Or hot air
might be forced into it as an agitator or even boiled by such hot air.
The steam which comes over with the ammonia will be condensed in
the upper chamber and will run down the sides into a suitable receptacle,
from which it may be drawn off in any suitable manner, or it may run
into the bottom chamber a.
I may here state that I am aware that the mere distillation of
ammonia from gas liquor is not new, but heretofore it has been attended
not only with danger but great expense, and a considerable nuisance
arises from the smell of the escaping vapours, whereas according to my
Invention all the vapours will be confined, and cannot therefore become
a nuisance as heretofore. The ammonia may also, if desired, be made
to pass through purifying agents previous to passing into the acids,
but if the compound is intended to be used as a manure, for which it
will be specially applicable, no purifying process will be required.
I would here remark that the apparatus shewn in the Drawings and
above described is more particularly intended to be used for operating
upon moderate quantities of liquor, and for this reason is constructed of
iron and is made portable so that it can be transported from one gas-
works to another if required, but when dealing with large quantities, as
in extensive gasworks, the apparatus must be of a more massive and
permanent character than that shewn. The acid combined with sawdust,
spent tanners' back, peat, and such like vegetable substances is to be
placed upon any suitable number of perforated trays arranged one above
the other over the chamber or vessel containing the gas liquor. When
the latter is heated the ammonia mixed with steam will rise up and
pass through the pulverized or comminated substance on the trays, and
the acid contained therein will seize or take up the ammonia as it passes
through, so that at the upper part of the chamber there will be nothing

page_text: but steam, and as no noxious smell will be evolved in this case the
uncondensed vapours may be allowed to escape into the air.. If desired
superphosphate of lime or other chemical agents may be used in
combination with the acidulated vegetable substances or simply with
the acid on suitable trays.
Having now described my Invention of improvements in the mode
of extracting ammonia, purifying gas liquor, and utilizing the same, and
having explained the manner of carrying the same into effect, I claim
as the Invention secured to me by Letters Patent as aforesaid, treating
ammoniacal gas liquor in close vessels or chambers as herein set forth
for the purpose of preventing the escape of disagreeable smells or
noxious vapours while the ammonia gas is combining with acids or
other chemical agents so as to form useful compounds.
In witness whereof, I, the said Alexander Rollason, have hereunto
set my hand and seal, this Fifteenth day of January, in the year
of our Lord One thousand eight hundred and seventy.
ALEXANDER ROLLASON. (L.S.)