IMPROVEMENTS IN THE MANUFACTURE AND PURIFICATION OF GAS
Year: 1852

page_text: LETTERS PATENT to George Michiels, of 57, Holywell Street,
Westminster, in the County of Middlesex, for the Invention of
"IMPROVEMENTS IN THE MANUFACTURE AND PURIFICATION OF GAS."
Sealed the 2nd March 1853, and dated the 16th December 1852.
PROVISIONAL SPECIFICATION left by the said. George Michiels
at the Office of the Commissioners of Patents, with his Petition,
on the 16th December 1852.
I, GEORGE MICHIELS, of 57, Holywell Street, Westminster, in the
County of Middlesex, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE MANUFACTURE AND PURIFICATION
OF GAS" to be as follows:
My Invention consists of the application of the oxygen of the
atmosphere which has been separated from the nitrogen. This
pure oxygen I drive into an oven previously charged with bitumi-
nous coal, or other material containing carbon, as soon as the
materials are ignited. By this operation the oxygen associates
with the carbon, and I obtain a gaseous product which is called
oxide of carbon gas, which will be found highly useful for the
purpose of obtaining heat.

page_text: My Invention for purifying ordinary gas for lighting purposes
consists in the injection of the pure oxygen of the atmosphere into
the current of gas coming from the retort.
SPECIFICATION in pursuance of the conditions of the Letters
Patent, filed by the said George Michiels in the Great Seal
Patent Office on the 16th June 1853.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I,
GEORGE MICHIELS, of 57, Holywell Street, Westminster, in the
County of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Sixteenth day of December,
in the year of our Lord One thousand eight hundred and fifty-two,
in the sixteenth year of Her reign, did, for Herself, Her heirs and
successors, give and grant unto me, the said George Michiels,
Her special licence that I, the said George Michiels, my executors,
administrators, and assigns, or such others as I, the said George
Michiels, 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, 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 MANUFACTURE
AND PURIFICATION OF GAS," upon the condition (amongst others) that
I, the said George Michiels George Michiels, by an instrument in
writing under my hand and seal, 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 George Michiels, do hereby
declare the nature of the said Invention, and in what manner
the same is to be performed, to be particularly described and ascer-

page_text: tained in and by the following statement thereof (that is to
say):
My Invention consists of the application of the oxygen of the
atmosphere which has been separated from the nitrogen. This
pure oxygen I drive into an oven previously charged with bitu-
minous coal, or other material containing carbon, anthracite coal,
or coke, as soon as the materials are ignited. By this operation
the oxygen associates with the carbon, and I obtain a gaseous
product which is called oxide of carbon gas, which will be found
highly useful for the purpose of obtaining heat.
My Invention for purifying ordinary gas for lighting purposes
consists in the injection of the pure oxygen of the atmosphere into
the current of gas coming from the retort.
And, in order that my Invention may be most fully understood,
I will proceed to describe the means pursued by me.
The oxygen which is to used in carrying out my Invention is
to be produced by extracting it from the atmosphere, according to
the now well known chemical fact that the oxide of barium, at one
temperature, will absorb oxygen, allowing the nitrogen to pass
untouched, and at another temperature will evolve oxygen, which
may be collected in a gasholder; to which process of obtaining
oxygen I make no claim.
The oxygen is to be induced to pass through a layer of ignited
carboniferous matter placed in a gas generator, which I construct*
in the way shewn in the accompanying Drawing.
The carboniferous matter may consist of charred wood, charcoal,
peat, coal, or coke. The peculiar feature in the gas generator is,
that it is put in connection with the oxygen holder, and that it is
also in connection with an exhausting apparatus.
of
If such a gas generator be charged with any, or with a mixture
any, of the aforesaid carboniferous matters, and this charge be
ignited, the oxygen drawn through it by means of the exhauster, will
be transformed into a combustible gaseous product called oxide of
carbon. During this process a large quantity of caloric is evolved.
I apply this heat to the decomposition of steam, by the injection of

page_text: furnishes a combustible gascous mixture, which will be found highly
useful for the production of heat. Such a mixture I shall in the
future call fire gas.
DESCRIPTION OF THE DRAWING.
A, feeding box, to receive the carboniferous matter. Its capacity
should be equal to the quantity of carboniferous substance to be
turned into gas in one hour, so as to be obliged to open the com-
munication between the reservoir and the gas generator only once
in that time. B, B, bottom of feeding box, with two radial openings.
It moves round its centre on a cast iron plate, which forms the top
of the gas generator, and which also has two openings placed in the
direction of the radii, as B, B. By this disposition, the communication
between the feeding box and the gas gencrator can be opened or
shut by a quarter turn. C, C, valves to cut off the action of the
exhauster during the charging of the apparatus.
It would be equally easy to exclude the atmospheric air, by
putting a lid with a hydraulic joint on the feeding box during the
introduction of the charge; in which case the shutting of the
valves C, C, may be dispensed with. D, interior of the gas gene-
rator, which has to be supplied with the carboniferous substances
which are to be converted into gas.
An indicator, consisting of a cast iron ball fastened on to the end
of the rod, working vertically through a stuffing box, is placed on the
top of the apparatus; so that, by lifting up this ball to the top of
the charge cach time that it is renewed, the relative position tells
when the apparatus requires fresh charging. E, E, steam boiler
surrounding the gas generator. This boiler can be made to supply
the steam for the injection, and the power for driving the exhauster.
If steam is not wanted, gas generator may be lined with fire brick
H, H. F, F, service holes placed in tiers on the circumference.
These openings allow free access, at pleasure, to the interior of the
gas generator, for separating with a poker the adhering masses;

page_text: detaching and breaking the clinkers, maintaining the whole mass in
a sufficiently loose state to permit a free passage to the oxygen,
and also for retaining every part of the mass in a state of com-
bustion. When the apparatus is in regular working order, these
service holes are to be closed with luted plugs. G, pipes through
which the injection (for cooling the apparatus, and increasing
the combustible richness of the gas) are forced. I, pipe for carrying
off the gas from the generator, under the influence of the exhauster.
J, basement chamber, for the reception of the cinder, and for the
cleaning of the fire place. It is in connection with the oxygen
holder, but can only be got at by means of an opening furnished
with double doors for the exclusion of the atmospheric air. When
several gas generators are erected near one another, it is well to
make these several openings communicate perpendicularly with one
main channel; which will allow of the cinder and scoria being
carried away in waggons on a tram way.
I will now proceed to describe the purification of gas:- My In-
vention for purifying gas consists in the injection of oxygen (pro-
duced in the way here above explained) into the current of gas
coming from the retorts, and which is to be purified by dry lime in
a set of ordinary purifiers.
I begin by ascertaining how much sulphur the foul gas carries
with it, and I inject at least double the quantity of oxygen that
would be necessary for forming with the sulphur hyposulphurous
acid; the result of which is, that when the foul gas passes through
the lime purifiers, the sulphuret of calcium, ordinarily formed there,
is transformed by the oxygen into pyposulphite of lime, and this
byposulphite of lime is subsequently converted by the ammonia of
the foul gas into hyposulphite of ammonia, the base of the acid;
viz., the lime being set at liberty, serves for further purification.
By this process, lime becomes a useful agent, not only for puri-
fying gas from carbonic acid gas and sulphur, as it does in the
method at present in use, but also for extracting ammonia; and
this way
the foul lime, being charged with hyposulphite of ammonia,
becomes a valuable article of trade. I have above stated, that I

page_text: inject more oxygen than is chemically necessary; and I do so for
the purpose of facilitating, and making sure, of the intended result
above described, considering that the excess of oxygen remaining
in the gas can do no harm, but, on the contrary, enhance its lighting
power.
I have here given, to the best of my knowledge, the most
efficient mode of purifying gas by lime, and of giving value to the
lime, by charging it with hyposulphite of ammonia. But there is
another way of obtaining the same result, less efficient, it is truc,
but still very useful, when no pure oxygen is at hand. In this case
I proceed as follows:
Having a set of dry lime purifiers at work, and one of them
having become foul, I put it out of action, and drive through it, by
a propeller or exhauster worked by a steam engine, a large quantity
of air, say fifteen thousand cubic feet per hour, through a purifier
of 100 square feet; and I continue to do so during five hours. Then
I remove the lid, and replace half of the foul lime by fresh lime, so
that the purifier contains the half new charge of lime on one side of
an ideal vertical plane passing through the centre line of the puri-
fier, and on the other side the foul line which has undergone the
process of mechanical ventilation. This being done, I shut the air
passages, and bring this purifier again in action. When the foul
gas passes through it, the ammonia will be detained in the state of
hyposulphite of ammonia, in the ventilated foul lime, by chemical
decomposition, already explained when speaking of pure oxygen;
and the carbonic acid gas, and sulphuretted hydrogeo of the foul
gas, will be detained partly by lime set at liberty in the ventilated
foul lime, and partly in the fresh lime. All the boxes of the set off
purifiers being similarly worked, the result will be, that the process
of purification by lime will be complete; and that the foul lime,
when removed, after having been twice at work in two successive
rotations of the purifiers, will contain all, or nearly all, the ammonia
in the state of hyposulphite of ammonia.
I wish it to be clearly understood that I know that attempts have
been made to obtain some such results by ventilating the purifiers

page_text: by the assistance of the draught of the chimney; but I am also
aware that these attempts have been failures, the insufficient and
irregular ventilation having been inadequate to carrying away the
caloric evolved by the combustion of the sulphur; and hence the
heat accumulated in the purifiers endangering the use of such a
method. To meet this difficulty, I have mentioned a quantity of
air, the oxygen of a very small portion of which is used chemically
for the burning of the sulphur, the larger amount being introduced
for the purpose of carrying away the caloric at the rate it is
evolved.
In witness whereof, I, the said George Michiels, have hereunto
set my hand and scal, this Sixteenth day of June, in the
year of our Lord One thousand eight hundred and fifty-
throo
Witness,
S. CARPMAEL.
G. MICHIELS. (L.S.)