IMPROVEMENTS IN GAS RETORTS AND APPARATUS USED THEREWITH
Year: 1876

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane, in the
County of Middlesex, Patent Agent, for the Invention of "IMPROVEMENTS IN
GAS RETORTS AND APPARATUS USED THEREWITH." A communication from
abroad by Aristide Edouard Servier, of Paris, France.
Sealed the 23rd September 1870, and dated the 20th April 1876.
PROVISIONAL SPECIFICATION left by the said Alexander Melville Clark at
the Office of the Commissioners of Patents on the 20th April 1876.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent. "IMPROVEMENTS IN GAS RETORTS AND APPARATUS USED THERE-
WITH."
The object of this Invention is to produce gas by a novel and more economical
means than those at present in use.
To accomplish this object I enclose the coal to be distilled in iron or clay cylinders
or tubes, which are placed one upon the other in an ordinary D retort until the
latter is completely filled, the process of extraction or distillation is then carried on
in the ordinary manner. I also replace the old D retort by one composed of a
number of tubes, which in conjunction with the use of tubes for distillation possesses
many advantages.
It is well known that in the manufacture of gas the coal is enclosed in a retort
made of iron or clay. The coal is supplied by means of a shovel or by scoops of
different forms, which are drawn out of the retort as soon as they have deposited
the coal therein. Skilled workmen are required to perform this operation as the
floor of the retort must be covered with a layer of uniform depth, otherwise all
the caloric would not be utilized and the coal would be unequally distilled. More-
over the coal must only fill the retort to a certain height, as during the distillation
and transformation into coke it swells much, and thus yields a coke at once light
and porous, which is good enough for domestic use or for certain manufactures not
requiring a very elevated temperature, but is of no service for metallurgy or steam
engines, thus limiting its sale and depreciating its value.
By means of this Invention I am enabled to dispense with the employment of
skilled workmen, to utilize the whole area of the retort, and produce a greater
quantity of gas for the same expenditure of fuel, and a superior kind of coke.
[Pavice 6d1
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page_text: This Invention is illustrated in the accompanying Drawings, Figure 1 of which
shows an end view and longitudinal section of an iron cylinder or tube a in which
the coal is placed, having the diameter of the coke required and made of the same
length as the retort. The tube is closed at one of its ends.
Figure 2 shows an end view of an crdinary D retort filled with tubes a.
Figure 3 shows an end view, and Figures 4 and 5 an elevation and longitudinal
section on A, B, of the tubular retorts of this Invention.
By filling the tubes a more or less a greater or less space will be left for the
swelling of the coal, and the density of the coke can be thereby regulated. Sufficient
space should always be left above the coal in the tube to allow of the escape of the
gas when formed. An ordinary gas retort can be filled with these iron tubes
superposed one above the other in such a manner as to fill the retort (see Figure 2).
The tubes can either be placed with their open ends towards the extremity of the
retort, as at a¹, Figure 5, or towards its mouth, as at a; in the latter case the gas
generated flows immediately into the outlet pipe, which conducts it to the hydraulic
main, in the former case it is caused to flow along the red hot sides of the retort
in making its way towards the ascension pipe. The tubes may be perforated with
small holes throughout their whole length to facilitate the escape of the gras.
As
the tubes can be charged whilst the distillation is going on in others, it is to easy to
see that they can be drawn out of the retort and others ready charged put in with
rapidity and at any moment without any sensible loss of gas by an ordinary
journeyman.
The coke can be extracted from the tubes without the necessity of cooling it by
the agency of water, exposure to the air almost always sufficing for this purpose.
The coke is emptied out of the iron tubes, when cooled, by holding them in a
vertical position with the open end downwards and then striking them lightly.
The great advantage of this Invention is that multitubular retorts can be employed
which will hold a great number of the tubes a, at the same time the said tubes
being made either cylindrical, conical, oval, or of other form.
The iron tubes resist the wear and tear in a very satisfactory manner, and they
are as it were transformed into steel after having been exposed to such an elevated
temperature in presence of the gas produced. The expense occasioned by the
employment of these tubes is thus insignificant as compared with the results obtained,
owing to the great conductibility of the iron, also the time required for distillation
is reduced, thus giving each retort a greater power of production for the same
expenditure of fuel.
By employing the arrangement of tubular retort, Figures 3, 4, and 5, an increased
heating surface is obtained. The retort consists of a series of tubes b, closed at one
end and united at the other end in a ring c attached to the mouth d of the retort.
These tubular retorts may be arranged either horizontally, as shown, or vertically,
the insertion and removal of the tubes a being as easy in the one case as the
other.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by the
said Alexander Melville Clark in the Great Seal Patent Office on the 17th
October 1876.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent. "IMPROVEMENTS IN GAS RETORTS AND APPARATUS USED THERE-
WITH." A communication from abroad by Aristide Edouard Servier, of Paris,
France.
This Invention relates to improvements in the distillation of gas from coal, and
consists, 1st, in enclosing the coal to be distilled in tubular cases of iron or clay
which are then placed either in an ordinary D retort or in a retort of special con-

page_text: struction until it is completely filled, the retort being then closed and the process
of distillation carried on in the ordinary manner.
The Invention consists, 2ndly, in the employment in lieu of the D retort of a
retort composed of a number of separate tubular chambers, each adapted to
receive one of the tubular cases containing the coal for distillation. This tubular
form of retort possesses many advantages. It is well known that in the ordinary
way of making gas the retorts are charged by scoops of different forms, which
are withdrawn after depositing the coal in the retort. Skilled workmen are
required for this operation as the floor of the retort must be covered with a uniform
layer of coal, otherwise all the heat would not be utilized and the coal would be
unequally distilled. Moreover, the retort must only be partly filled as the coal swells
during the distillation, and yields a coke at once light and porous, which although
good enough for domestic use and for certain manufactures not requiring very high
temperatures is useless for locomotives and for metallurgical operations. Its sale is
thus limited and its value depreciated.
By this Invention the employinent of skilful workmen for charging and drawing
the retorts is dispensed with, the whole capacity of the retort utilized, and a larger
quantity of gas and a superior kind of coke obtained for the same expenditure of fuel.
This Invention is illustrated in the accompanying Drawings Figure 1 of which
shows an end view and longitudinal section of one of the iron tubes or cases a in
which the coal is placed. This tubular case a is closed at one end and is of the
same length as the retort, and of a diameter proportioned to the size of the coke
required.
Figure 2 shows an end view of an ordinary D retort filled with these tubular cases a.
Figure 3 shows an end view, and Figures 4 and 5 an elevation and longitudinal
section on line A, B, of the tubular retorts forming the second part of this
Invention.
The iron tubes a charged with coal may be superposed one above the other in
an ordinary gas retort in such a manner as to completely fill the retort as in
Figure 2, and the tubes can either be placed with, their open ends towards the
back end of the retort, as at a¹, Figure 5, or towards its mouth, as at a; in the latter
case the gas generated flows immediately into the ascension pipe, whereas in the
former case it must flow along between the case a and the red hot sides of the
retort to the ascension pipe. The tubes a may be perforated with small holes
throughout their whole length to facilitate the escape of the gas."'" A number
of the tubes can be kept charged in readiness to be quickly put in when those in
the retort are drawn out, which may be done at any moment without any sensible
loss of gas by an ordinary journeyman. The density of the coke may be regulated
by leaving more or less room for the coke to swell when the tubes are filled;
sufficient space should, however, always be left above the coal for the escape of
the gas.
The coke can be extracted from the tubes without the necessity of cooling it with
water, exposure to the air almost always sufficing for this purpose. The coke is
emptied out of the iron tubes when cooled by holding them with the open end
downwards and tapping them lightly.
The great advantage of this Invention is that the whole capacity of the retort
being filled with cases charged with coal, as seen in the end view, Figure 2, a
greater quantity of coal may be distilled in each retort than when they are charged
in the ordinary way.
The iron tubes resist the wear and tear in a very satisfactory manner, and they
are as it were transformed into steel after having been exposed to such an elevated
temperature in presence of the gas produced. The expense occasioned by the
employment of these tubes is thus insignificant as compared with the results
obtained, owing to the great conductibility of the iron, also the time required for
distillation is reduced, thus giving each retort a greater power of production for the
same expenditure of fuel. The tubes may be of circular, oval, or rectangular section,
and either of parallel, conical, or other form.

page_text: By employing the arrangement of tubular retort, Figures 3, 4, and 5, an increased
heating surface is obtained, cach tubular chamber of the retort being made to
receive a tube charged with coal. The retort consists of a series of tubes b closed
at one end, and united at the other end in a ring c attached to the mouth d of the
retort.
These tubular retorts may be arranged either horizontally, as shown, or vertically,
the insertion and removal of the tubes a being as easy in the one case as the other.
Having described the nature of the said Invention, and the manner of performing
the same, I declare that what I claim as the Invention to be protected by the
herein-before in part recited Letters Patent is, the application and use for dis-
tilling coal of cylinders or tubular cases, substantially as and for the purpose set
forth, also the employment in combination therewith of tubular retorts as and for
the purposes specified.
In witness whereof, I, the said Alexander Melville Clark, have hereunto set
my hand and seal, this Seventeenth day of October, in the year of our Lord
One thousand eight hundred and seventy-six.
A. M. CLARK. (L.S.)