IMPROVEMENTS IN THE MANUFACTURE OF GAS ANDIN APPARATUS THEREFOR, AND FOR CARBURETTING AND PURIFYING THE SAME."
Year: 1879

page_text: LETTERS PATENT to Horatio Richard Snelgrove, of Craven Street Strand, in the
County of Middlesex, Associate of the Institute of Civil Engineers, for
the Invention of "IMPROVEMENTS IN THE MANUFACTURE OF GAS ANDIN
APPARATUS THEREFOR, AND FOR CARBURETTING AND PURIFYING THE SAME."
DELLT 1000 in
Order of the Lord Chancellor and
PROVISIONAL SPECIFICATION left by the said Horatio Richard Snelgrove
at the Office of the Commissioners of Patents on the 12th December 1879.
HORATIO RICHARD SNELGROVE, of Craven Street, Strand, in the County of
Middlesex, Associate of the Institute of Civil Engineers. "IMPROVEMENTS IN THE
MANUFACTURE OF GAS AND IN APPARATUS THEREFOR, AND FOR CARBURETTING
AND PURIFYING THE SAME."
My Invention relates to the manufacture of gas, and to improved means for
enriching the same with hydro-carbons, and comprises various novel apparatus
hereinafter described.
By means of my said Invention I am enabled to produce a larger proportion of
gas from the same amount of fuel than has been heretofore practicable; moreover
the gas so produced becomes freed from nearly the whole of its impurities as it
passes through the said apparatus, and is delivered in a condition of high
illuminative power, the cost of production being much less than is possible with
the apparatus now ordinarily in use.
In carrying the said Invention into practice I provide a retort, the sides or walls
of which are made inclined or taper, the widest portion being at the base. The
retort may be either vertical or horizontal, and inay be made of fite-clay, iron, or
other suitable material. The interior walls of the retort may be provided with
grooves designed to serve as passages for the rising gas.
Below the retort and attached thereto I provide a chamber or vessel into which
the spent coal or coke is admitted from the retort. The coke remains in the said
chamber during the distillation of a new charge. By allowing the coke to fall into
this chamber it is permitted to cool gradually, and any gas which may still remain
in it when removed from the retort will pass upward into the latter, and be

page_text: utilized instead of being wasted. Moreover this coke will be of better quality than
that treated in the ordinary manner
There may be any number of such retorts, and in setting the same I provide a
projecting fire-place or furnace, as the fire cannot be immediately underneath the
retort, this space being occupied by the aforesaid chamber.
I also provide one or more tubes or chambers in or in connection with the retort
fornace, and so arranged that they will be maintained in a heated condition whilst
the retort is in action; the said tubes or chambers are each furnished with an
internal tube provided with perforations in its walls. Water is caused to flow into
the internal tube, and as it escapes through the apertures and comes in contact
with the heated walls of the outer tube steam is generated, which being conveyed
into the retort or into the bydraulic main, as desired, acts as an exhauster, and
creating a draught aids in causing the gas to flow. This steam is also of great use
for scrubbing the gas with which it comes in contact to remove ammonia
therefrom.
Another improvement consists in attaching to the mouth piece, feeder, or other
part of the retort a series of cones, pipes, or tubes (in which water may or may not
be made to circulate, so as to regulate the temperature for purposes of condensing)
arranged within an enclosed vessel or covering. The object of this apparatus is to
partially condense and catch the rich carbon during distillation, the inclined
surfaces of the cones, pipes, or tubes causing the carbon to fall back into the retort
for regeneration.
The hydraulic main may be either vertical or horizontal, and may be provided
with a series of divisions or chambers. I place in the said main one or more
revolving drums or screens provided with arms or floats. These drums are caused
to revolve by the gas, which thus comes into contact in its passage with the water
brought up by the arms or floats, the gas being thereby much more effectively
scrubbed than by any method heretofore employed. In some cases I also employ
divisions either movable or fixed in the hydraulic main for the purpose of dis-
tributing and depressing the gas over and upon the surface of the water for the
better absorption of ammonia and other impurities. These divisions may be hung
loosely by their upper portion, so that the passing gas will deflect them, the effect
being to cause the gas to be pressed against the water. These divisions may be
used in connection with the drums or in lieu thereof, or the drums may be used
without any such divisions.
Another feature of my Invention consists in providing a valve or inlet of peculiar
construction for the purpose of relieving the retorts during the time they are in
action from undue back pressure. This valve consists of a cup or bowl, and is
placed below the ordinary dip pipe, whose lower extremity extends nearly to the
bottom of the said bowl. The latter is partly below the water line, and is provided
with perforations whose area is calculated pro rata with respect to the area of the
ascending main from the retorts and the pressure within the same, so that the
incoming gas will force the water out of the bowl, thus unsealing the pipe and
passing into the space above the water in the hydraulic main. As soon as the pressure
ceases the surrounding water flows into the bowl through the perforations and
re-seals the pipe. It will be seen that this valve is self acting, and the water in
the bowl acts as a powerful scrubber to the passing gas.
Another part of my said Invention relates to a purifyer, which I construct with
a vertical central division or divisions. I provide the said purifyer with screen or
gratings consisting of flat or bevelled oxidized bars which may be slightly raised at
their edges, and with transverse bars raised or not raised. I prefer to use as a
purifying medium within the said purifyer rusty wire, rusty scrap iron, rusty
borings, or rusty metal in any other suitable form for filling the aforesaid screens
or gratings instead of lime which is ordinarily used. I also provide the said
purifyer with an inlet and an outlet cock or valve for passing atmospheric air
through the purifyer to re-oxidize or revivify the purifying medium without
having to remove the same.

page_text: My Invention further comprises an apparatus, chiefly designed to be used in
public and other buildings, for purifying and carburetting the gas supplied to such
buildings from the ordinary gas works. This apparatus is so constructed as to
utilize the air, and at the same time to absorb the sulphur, ammonia, and other
impurities in the gas, and to cause the gas and air to pass through and take up
hydro-carbon, thus making the gas much purer and richer than when it entered
the said apparatus.
In some cases this apparatus may be used in conjunction with the gas producing
apparatus hereinbefore described.
The said carburretting apparatus is constructed as follows, that is to say :-I
provide within a closed vessel a series of gratings, screens, or, sieves made of flat,
bevelled, or plain bars, which may be placed across each other. I employ brackets,
standards, or other devices for supporting and dividing the said sieves or gratings,
which are placed one above another. I place within the divisions thus made oxide
of iron, cotton, asbestos, wool, or other suitable absorbent material, and I prefer
to provide one compartment with the oxide of iron, and the next compartment
with the wool or other absorbent material, and so on alternately. To the upper
part of the apparatus I attach a pipe with a cup at its upper end, and with a cock
beneath the said cup. The lower end of the tube dips into a vessel within the
outer casing of the apparatus. The liquid hydro-carbon (preferably benzoline)
designed to enrich the gas is poured into the said cup and passing through the
tubo enters the said vessel, and when the latter is full flows over its edges upon a
perforated plate or disc at the upper part of the apparatus, whence it passes down-
ward into the compartments between the gratings or sieves, and the wool or other
inaterial therein becomes saturated. By means of the said vessel and pipe I am
enabled to supply the said apparatus with hydro-carbon at any time without putting
out the lights, as the gas cannot escape through the vessel and pipe wien charged
with the liquid hydro-carbon. In some cases instead of providing a vessel for
the pipe to dip into I merely bend the lower extremity of the said pipe upward,
so that the liquid hydro-carbon will pass from the end of this turned up portion to
the perforated disc or plate. The effect will be practically the same as when using
the said vessel.
In some cases it may be desirable to feed the apparatus with the liquid hydro-
carbon from a distant point situated either outside the building in which the
carburetting apparatus is placed or at some other part thereof. In such a case I
provide a vessel which is placed in any convenient or desired position, and is
supplied with a quantity of liquid hydrocarbon. This vessel is furnished with a
self acting supply valve or cock of any suitable construction, and is connected with
the carburetting apparatus by a pipe or tube. By these means the carburetting
apparatus is supplied automatically with the liquid hydrocarbon as required. The
carburetting apparatus is suitably attached to the supply pipe leading from the
meter.

page_text: I also provide one or more tubes or chambers within or in connection with the
retort furnace, and so arranged that they will be maintained in a heated condition
whilst the retort is in action; the said tubes or chambers are each furnished with
an internal tube provided with perforations in its walls. Water is caused to flow
into the internal tube, and as it escapes through the apertures and comes in contact
with the heated walls of the outer tube steam is generated, which, being conveyed
into the retort or into the hydraulic main as desired, acts as an exhauster, and
creates a draught, thereby effecting the flow of the gas. This steain is also of
great use for scrubbing the gas with which it comes in contact to remove ammonia
therefrom.
At the upper part of the retort a I arrange a closed condensing vessel or
chamber c, which is attached to the mouth-piece or other part of the retort, and is
provided with an aperture & to enable the retort to be fed, the said feed aperture
being closed by a door or cover of any suitable construction. Within this
chamber c I arrange a series of cones e placed upon a screw-rod f, and secured
upon the same by a screw nut fl or otherwise These cones or conical pieces e
serve to partially condense and catch the rich carbon during distillation, the
inclined surfaces of the said cones causing the carbon or tar to fall back into the
retort for regeneration. Or instead of employing the cones 1 in some cases
arrange in the interior of the chamber ca series of pipes or tubes, preferably
forming a cone, through which water may be made to flow so as to regulate the
temperature of said cone, and thus condense the tar; g represents the pipe leading
from the retort to the hydraulic main
I will now proceed to describe my improved devices employed in connection
with the hydraulic main h, which may be either vertical or horizontal, and pro-
vided with a series of divisions or chambers. I place in the said main one or
more revolving drums or screens i, provided with arms, paddles, or floats ; these
drums are caused to revolve by the pressure of the gas which comes into contact
with the arms in its passage through the main. The water is thus constantly
agitated by the arms or floats i, the gas being thereby much more effectively
scrubbed than by any method heretofore employed In some cases I employ
divisions or partition plates j, either movable or fixed, in the hydraulic main for
distributing and causing the gas to descend to and pass over the surface of the
water for the better absorption of ammonia and other impurities. These division
plates may be hung loosely by their upper portion, so that the passing gas will be
deflected, the effect being to cause the gas to be pressed against or in contact with
the water. These division plates may be used in connection with the drums i, or
in lieu thereof, or the druins inay be used without any such divisions.
Another feature of my Invention consists in providing a valve or inlet devices
of peculiar construction for the purpose of relieving the retorts whilst in action
from undue back pressure; this valve consists of a cup or bowl & which is placed
below the dip pipe g' forming part of or attached to the pipe g, and whose lower
extremity extends nearly to the bottom of the said bowl; this bowl is partly
below the water line as shewn, and is provided with a series of perforations whose
area is calculated in proportion to the area of the pipe g from the retorts and the
pressure within the same, so that the incoming gas will force the water out of the
bowl, thus unsealing the pipe, and will pass into the space above the water in
the hydraulic main. As soon as the pressure ceases the surrounding water flows
back into the said bowl through the perforations and re-seals the pipe gl. It will
be seen that this valve is self-acting, and the water in the bowl acts as a powerful
scrubber to the passing gas!
In constructing a purifier I provide the same with a vertical central division or
divisions. I also provide the said purifier with trays, screens, or gratings con-
sisting of flat or bevilled oxidized bars which may be slightly inclined, and with
transverse bars for supporting the said inclined bars. I prefer to use as a
purifying medium within the said purifier rusty metal in the form of wire, scrap
iron, or borings, or in any other suitable form for filling the aforesaid trays, screens,

page_text: or gratings instead of lime which is ordinarily used. I also provide the said
purifier with an inlet and an outlet cock or valve for passing atmospheric air
through the purifier to re-oxidize or revivify the purifying medium without
having to remove the same.
Another part of my Invention, which is illustrated in Figures 4 and 5, relates to
apparatus chiefly designed to be used in public and other buildings for purifying
and carburetting the gas supplied to such buildings from the ordinary gas works;
this apparatus is so constructed as to utilize the air and at the same time to absorb
the sulphur, ammonia, and other impurities in the gas, and to cause the gas and
air to pass through and take up hydro-carbon, thus making the gas much purer
and richer than when such an apparatus is not employed; this apparatus may if
desired be used in conjunction with the gas producing apparatus hereinbefore
described.
The said carburetting apparatus is constructed as follows, that is to say :-I
provide within a closed vessel n a series of gratings, screens, or sieves o consisting
of of flat, bevelled, or plain bars, which may be placed across each other. I prefer
however to form the said gratings as shewn in Figures 4 and 5, that is to say,
I employ a series of bars o' (preferably oxidized) which are inclined in opposito
directions as shewn. These bars are held at the proper distance apart by the
pieces o³, one of which is placed between each two of the bars o, the necessary
incline being produced by the centre piece o³. To secure together the whole of
the parts constituting the gratings I prefer to employ a screw rod or rivetted bolt p,
which passes through the bars o' and pieces o³, o³, and clamps thein firmly in their
proper relative position. To support the said grating, screens, or sieves one above
another in their proper relative position I provide the same with rings or flanges q,
or I employ brackets, standards, or other devices for supporting and dividing the
said sieves or gratings. Within the spaces or divisions between the said gratings,
screens, or sieves I place cotton or asbestos-wool or other suitable absorbent material.
To prevent the spaces between the bars o' becoming clogged or filled up by such
absorbent material, I prefer to cover the same with thin porforated metal sheets
or sheets of wire gauze. To the upper part of the apparatus I attach a pipe r
with a cup r¹ at its upper end, and with a cock 2 beneath the said cup. The lower
end of this tube dips into a vessel within the outer casing of the apparatus, or is
extended upwards above the perforated plate or discs as shown. The liquid
hydro-carbon (preferably benzoline) designed to enrich the gas is poured into the
cup and passing through the tube or piper enters the carburetter, and flowing
over the plate s is evenly distributed by the same, and passes downward into the
compartments between the gratings or sieves o, the wool or other material between
the same being thereby saturated. By means of the cup and pipe r I am
enabled to supply the apparatus with hydro-carbon at any time without putting
out the lights, as the gas cannot escape through the vessel and pipe when charged
with the liquid hydro-carbon. When the piper dips into a vessel in the car-
buretter the liquid hydro-carbon when the said vessel is full flows over the edge of
the same through the disc a in a similar manner to that above described.
t represents the service-pipe leading from the carburetter to the burners. In some
cases I arrange in connection with this pipe a pressure regulating valve u which is
attached by its rod u¹ to a flexible diaphragm u³. When a few burners only are
alight the pressure of the gas in the carburetter will raise the diaphragm u and
approximately close the valve, but when a greater number of burners are lighted
the pressure of the gas in the carburetter will be diminished, and the valve will
consequently fall by its own weight. By this means I prevent the passage from
the carburetter of more gas than can be thoroughly consumed by the burner or
burners alight, and thereby obviate any flaring or noise at the said burners.
In some cases it may be desirable to feed the apparatus with the liquid hydro-
carbon from a distant point situated either outside and adjacent to the building in
which the carburetting apparatus is placed, or at some other part. In such a case
I provide a vessel which is placed in any convenient or desired position and is

page_text: supplied with a quantity of liquid hydro-carbon; this vessel is furnished with a
self acting supply valve or cock of any suitable construction, and is connected with
the carburetting apparatus by a pipe or tube. By these means the carburetting
apparatus is supplied automatically with the liquid hydro-carbon as required.
Having thus fully described my said Invention and the manner of performing
the same, I wish it understood that I am aware of the apparatus described in the
Specification of Letters Patent granted to George Symes, and dated November 22nd,
A D. 1876, No. 4526, and that I do not claim as my Invention any of the features
set forth in his said Specification, but I claim the improvements as hereinabove
specified, that is to say,-
First. The improvements in the manufacture of gas resulting from the use of the
above described apparatus, as above set forth.
Second. The taper form of the retort and the combination of the same with the
spent-fuel chamber, as and for the purposes specified.
Third. In combination with the said retort the condensing vessel or chamber
constructed as shewn in the Drawing, and containing the conical condensing
devices, and provided with a feed-aperture and a pipe leading to the bydraulic main,
substantially as and for the purposes specified.
Fourth. The improvements in connection with or relating to the hydraulic main,
and comprising the devices for agitating the water and the valve, arranged and
operating substantially as above described and as shewn in the Drawing for the
purposes specified.
Fifth. The improvements relating to the carburetting apparatus and comprising
the novel construction of the trays or screens, the feeding arrangements, and the
means for regulating the pressure, substantially as and for the purposes specified.
In witness whereof I, the said Horatio Richard Snelgrove, have hereunto set
my hand and seal, this Twenty-eighth day of June, in the year of our
One Lord thousand eight hundred and eighty.