Process and Apparatus for the Manufacture of Coal-gas.
Year: 1899

page_text: Date of Application, 4th July, 1899-
1900
Complete Specification. Left, 4th Apr., 1900-Accepted, 16th June,
Process and Apparatus for the Manufacture of Coal-gas.
I, EDUARD BESEMFELDER, Doctor of Philosophy, of Kantstrasse 105°, Char-
lottenburg, in the Kingdom of Prussia, do hereby declare the nature of this
invention to be as follows:-
In the ordinary process for the manufacture of illuminating gas the coal is
subjected to destructive distillation in retorts heated from outside, the coke is
afterwards drawn off, allowed to cool and then used as a fuel. The heat con-
tained in the red-hot coke, when being discharged from the retort, is either
not utilized at all or only imperfectly, and the external heating the retorts is
also attended with considerable loss of heat.
80 as 'to
This invention has for its object, to combine various operations,
achieve an important industrial progress, that is to say, the continuous and
almost automatic working of a gas producer, with complete gasification of the
carbon contained in the coal, saving of labour, and without the consumption of
fuel for the direct heating of retorts, and an increased yield of gas in comparison
with the most advantageous process hitherto known, viz., the Delwick-process.
For this purpose I utilize the red-hot coke, as it comes from the gas retorts,
that is to say before it has had time to cool, for making water gas, I utilize
the heat with which the water gas leaves the gas generators for gasifying the
coal by conducting the gas from the generators directly into the gas retorts,
where it mixes with the gas liberated from the coal and then escapes as a gas
mixture, and I heat the gas retorts externally by the waste gases obtained from
the water gas producers during the preliminary or heating stage, which waste
gases are practically free from oxygen.
The apparatus for carrying out this process may assume a variety of forms;
the example hereafter described chiefly comprises the following parts or
devices:-
An inclined retort adapted to revolve on its axis by means of tooth gear, a
stuffing box and rollers, and supplied with fuel at the upper end by means of a
revolving feed-screw placed in the axis of the retort, a hopper receiving the
fuel from a bucket chain elevator and delivering it to the said feed screw, the
interior of the said retort being provided with helical transporting ribs attached
to the circumference of the retort, so as to deliver the fuel at the lower end to
an inclined shoot situated in the interior of a bent tube which forms the outlet of
the retort, a distributing device which receives the red-hot mass discharged
from the retort and distributes it to the water gas generators arranged in a
circular group below the outlet end of the bent discharge tube mentioned above.
The distributing device chiefly consists of a hollow distributing cone or
annular distributing receptacle mounted on the upper extremity of a vertical
shaft situated in the axis of the group of water gas generators, the said cone
br receptacle being fitted into the lower or outlet extremity of the bent dis-
charge tube mentioned above, a group of paddle wheels or distributing wheels
(one for each water gas generator) arranged around the said shaft and immedi-

page_text: ately underneath the distributing cone, but above the water gas generators
and coaxially with the same, the bearings of each paddle wheel being fixed to
the distributing cone so as to revolve with the same, and each paddle wheel
being adapted to receive some of the hot mass which drops through the dis-
tributing cone and to discharge it at the proper moment into the upper end of
one of the inclined feed pipes connecting the distributor with the top of the
water gas generators (one feed pipe or shoot for eacli generator), a stationary
distributing ring or annular box situated underneath the distributing cone,
the said ring serving as a support for the bent discharge tube coming from the
retort and forming connections with the inclined discharge tubes leading to the
water gas generators; the top of the said annular box or distributing ring has
as many horizontal flanges or inward projections as there are paddle wheels,
each projection being situated between two of the inclined discharge tubes,
and the paddle wheels extend downward into the said box or ring, so that
whenever during the revolution of the shaft a paddle wheel is placed radially
in line with one of the said projections or flanges, one of its blades will rest
upon the same so as to prevent the wheel from turning on its (horizontal) axis,
but when the wheel is in line with one of the inclined discharge tubes; the
blade will descend and allow the mass to fall into the inclined discharge tube.
During the heating stage of a water gas generator the connection between
the distributing ring and the generator is cut off by means of a rotary slide
adapted to close the upper end of the inclined discharge pipe, the said slide
being fixed to a sleeve mounted on the central shaft and adapted to turn inde-
pendently of the latter, said slide being also provided with a rest for the blades
of the paddle wheel, which prevents the latter from turning on its axis.
The individual water gas generators may be constructed in the usual manner;
but the necessary steam is preferably superheated in the water gas generator
by conducting it through helical tubes which are let into the iron jacket of the
generator.
The steam nozzles may be caused to draw from a suitable reservoir tar or
petroleum refuse aud to blow the same in a fine state of division into the red-
hot coke, in order to carburate the water gas, which then passes over the red
hot coke situated in the distributing apparatus and on the inclined shoot into
the interior of the retort, to mix with the gases generated in the latter, the
mixture being allowed to escape through a pipe at the upper end of the retort..
For heating the retort from outside by the waste gases produced during the
heating period of the water gas. generators, the retort is preferably surrounded
with a helical heating canal or flue.
Instead of a revolving retort,, as described above, a stationary retort with hori-
zontal coal feed produced by known means may be employed, the coal in the
retort being heated as far as the nature of the metal will allow it.
Tall his hf.1: 1000
FAIRFAX & WETTER,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Presses and Apparatus for the Manufacture of Coal-gan.
I, EDUARD BESEMFELDER, Doctor of Philosophy, of Kantstrasse 105, Char-
lottenburg, in the Kingdom of Prussia, do hereby declare the nature of this
invention and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement:--
In the ordinary process for the manufacture of illuminating gas the coal is
840.
I, EDUARD BESEMFELDER, Doctor of Philosophy, of Kantstrasse 105°, Char-
lottenburg, in the Kingdom of Prussia, do hereby declare the nature of this
invention and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement:-
In the ordinary process for the manufacture of illuminating gas the coal is

page_text: subjected to destructive distillation in retorts heated from outside, the coke is
afterwards drawn off, allowed to cool and then used as a fuel. The heat con-
tained in the red-hot coke, when being discharged from the retort, is either not
utilized at all or only imperfectly, and the external heating of the retorts is, also
attended with considerable waste of heat.
This invention has for its object, to combine various operations, so as to achieve
an important industrial progress, that is to say, the continuous and almost auto-
matic working of a gas producer with complete gasification of the carbon con-
tained in the coal, saving of labour, and without the consumption of fuel for
the external heating of retoris, and an increased yield of gas in comparison with
the most advantageous process hitherto known.
For this purpose I utilize the red-liot coke, as it comes from the gas retorts,
that is to say, before it has had time to cool, for making water-gas; I utilize
the heat, with which the water-gas leaves the gas generators, for gasifying the
coal, by conducting the gas from the generators directly into the gas retorts,
where it mixes with the gas liberated from the coal,, and then escapes as a
gas mixture, and I heat the gas retorts externally by the waste gases obtained
from the water gas producers during the proliminary or heating-up stage, which
waste gases are practically free from oxygen.
The apparatus for carrying out this process may assume a variety of forms,
some of which are illustrated by the accompanying drawings:-
Fig. 1 is a vertical section of a gas producing plant embodying my invention.
Figs. 2 to 5 represent details of construction.
Figs. 6 and 7 represent a modification of detail.
Fig. 8 is a vertical section of a modified gas producing plant.
Figs. 9 to 13 represent details of construction, those in Figs. 9, 12 and 13
being shown on a larger scale.
In the example represented by Fig. 1, a bucket chain 1 supplies the raw
material continuously to a funnel 6 leading to a transporting screw 3 which
is guided by a stuffing box 2 and situated in a tube extending into the head 4
of an inclined retort 5 revolving slowly on its axis..
The material from which the gas is to be extracted is fed along by means of
channel-shaped conducting ribs 7, secured to the periphery of the cylindrical
retort, at an angle to the axis of the same. The rotation of the retort and
the rate at which the material travels within the same should be so determined,
that the latter may leave the retort in a condition somewhat closely approaching
that of the coke from ordinary illuminating gas works. The red-hot material
treated in the retort, is delivered into a scoop 8, and thence drops into coaxially
arranged apparatus adapted to distribute it uniformly among three out of four
gas producers 9 erected underneath, while admission of charges of material to
the fourth generator, which happens to be in the preliminary blowing in or
heating up stage, is prevented by any suitable cut-off device. Instead of four,
any other suitable number of gas generators may be arranged around the axis
of the distributor.
In the form of apparatus illustrated in Figs. 1 to 5 inclusive, the distributing
device is driven by the shaft 10, and mainly consists of a hollow distributing
cone 11 rigidly secured to the said shaft, and the star-shaped groups of distribut-
ing blades or paddles 12, situated, each upon its own spindle, below such hollow
cone; one side of each of the blades 12, abutting upon one of the off sets 13
(Fig. 4) of the ring 14. When, however, any one of the distributing blades 12,
as the shaft 10 turns. is situated in the recess 15 existing between each
pair of projections 13, such blade will turn on its horizontal axis, so that the
material it carries is dicharged into the shoot 16 leading to the generator '9:
The device serving to provide for the sufficiently tight closing of the generator,
which is in the preliminary heating or blowing in stage, so as to avoid any
dilution of the water-gas with nitrogen and carbonic acid, and to keep any
further supply of gas-yielding material out of such generator, mainly consists

page_text: of a sliding door or valve 18, attached to a revoluble sleeve 17. This door or
valve carries a stop 19, with which the blades 12 (Fig. 1) are adapted to engage,
being thus prevented from swinging round at this point. At the end of the
blowing in stage in that generator, and when the generator in which the pre-
liminary heating is to take place next has been charged, the door or valve 18
automatically turns 90°, or any other suitable angle according to the number of
generators, and by so doing, closes the feeding shoot 16 of this last-mentioned
generator. This reversal of the slide or valve 18 is effected by a rotary movement
of the shaft 10; upon which is unted a belt pulley 20; a toothed wheel 21,
also arranged upon such shaft, seing geared with a set of tooth wheels 22; 23,
which engages with a toothed segment 24 and, at the same time, through the
medium of a tappet 25, effects the reversal of the steam supply to the generators,
as is clearly illustrated in Fig. 2.
These water gas producers are fitted with the well-known device for injecting
compressed air or superheated steam, the latter of which may be superheated in
the generator itself, to which end it may, in accordance with the Frederking
system, for example, be conducted through pipes let into the protecting iron
walls of the generator.
The steam jets acting by suction, extract tar or petroleum residues from a
reservoir with which they are suitably connected, such residues being thus
injected into the coke in the state of as fine a division as practicable: The water-
gas, so carburetted; sweeps over the red-hot coke on the (combined) distributing
and delivery apparatus, passes into the interior of the retort, and here, owing
to its high temperature, at the same time expels the constituents of ordinary
illuminating gas from the gas-yielding material which it meets; after which, on
mixing with these constituents, it leaves the retort through a vertical tube 26,
rising from the stationary front portion of such retort; the gas mixture there-
upon proceeding to the purifying or scrubbing apparatus well-known in con-
nection with the illuminating gas manufacture. Below the vertical tube 26 is
arranged a tar collector 28 fitted with a downwardly-opening lid or cover 27,
whence the tar issues laterally through a syphon 29.
The revoluble retort 5 is heated externally by the gases produced during
the blowing in stage of the water gas generators, and containing little or no
oxygen these gases flowing, for example, through a vertical tube 30 and the
flying dust collector 31,-into a cylinder 32 surrounding the retort 5, and being
here (with a view to the maximum utilization of their heat) conducted by resis-
tances such as 33, which may be provided either on the retort 5 or on the cylin-
der 32 so that the said gases are thus compelled to take a spiral course around
the retort.
In Figs. 6 and 7 is shown a modification of the apparatus for distributing the
coke which leaves the retort 5 in a red-hot condition. In this modified form, the
'red-hot coke drops out of the scoop 8 on to a conically inclined plane 34, and
thence into the three (or other suitable number of) open shoots 35. Both the
distributing cone 34 and the parts surrounding the shoota 35, are arranged
revolubly and set in motion by a shaft 10. The shoot 36 leading to the generator,
which is being heated up at the time, is closed by a ball 37 confined within a
cubical chamber 38 and adapted. to be lifted from its seat and conducted to the
inlet of the delivery shoot 36 leading to the next following generator, as the
shaft 10 revolvos.
To protect the iron parts, which are exposed to the influence of the highly
heated gases issuing from the generator, such parts should preferably be sur-
rounded with a casing of firebricks.
The fact that the extraction of gas from the carbonaceous material in the
retort proceeds slowly under the influence both of the heat of the water gas (which
heats the retort internally and of the gases escaping from the water gas pro-
ducers which are in the blowing-up stage (whereby the retort is heated extor-
nally), this is generally known to happen in the process now employed in the

page_text: manufacture of illuminating gas; whereas, on the other hand, the gasification
of the carbonaceous residue from the retorts takes place rapidly in the water
gas producers; this fact makes it necessary in practice, to use a retort of 'con-
siderable length, whenever it is desired, that the water gas generators be fed
with carbon holding residue from the retort in a manner consistent with con-
tinuous operation, and that, at the same time, the coal in the retort, as it
travels through the latter, be freed from gas to as full an extent as practicable.
In many cases, therefore, it is advisable, with a view to the-accomplishment
of the object just stated, to employ a series of short retorts arranged one below
the other, instead of one long retort; or in other words to divide the retort into
a number of compartments placed one under the other; and further, to locate
a portion of the work to be performed in the retort, viz., the extraction of gas
from carbon-holding material,—within a shot-tower attached to; and forming,
as it were, an extension of the retort or retorts.
In the apparatus represented in Figs. 8 to 13, 39 is the elevator by which
the coal or other carbonaceous material is supplied to the funnel or hopper 40
provided with distributing rollers 41, whence it drops into the uppermost of the
horizontal retorts 42. The retorts are provided with transporting screws. 43
which receive rotary motion from a belt pulley 44 through the medium of
toothed gearing 45, and whereby the material is gradually conducted through
each one of the retorts alternately connected with each other at the front and
at the back end, so that, upon eventually leaving the retorts, the coke or car-
bonaceous residue may be delivered into the shot tower 46 attached to the lower
retort and fitted with distributing plates 47. Both the distributing plates and
the tower itself are covered or jacketed with fire bricks. Within the shot tower,
which is preferably provided with spy holes 48, the material, from which part
of the gas has already been extracted in the retorts, slides downwards from
plate to plate, thus moving in a direction opposite to that of the water gas
rising from the water gas producers which are arranged below the tower; under
the action of the heat of which gas the said material undergoes a further gas-
extracting process. The gas mixture thus obtained passes from the tower into
the lower-most retort, and thence, moving in the opposite direction to that of
the carbonaceous material, passes through all the retorts in succession and
effecting as it does a partial gas extraction from the material under treatment.
Finally the gas mixture leaves the retorts through the escape device 74, 75.
To provide for the carburization of the gas, and generally for the effective
gasification of the tar or the petroleum residues obtained in the course of opera-
tion, the shot tower at its upper part, above the plates, carries a reservoir 66,
having an outlet 67 for the tar etc., and a steam injector 68 serving to force
the tar or the petroleum residues contained in the reservoir, into the tower.
To ensure the requisite balance of pressure, the reservoir is furthermore con-
nected at its upper part with the tower by an escape pipe 69 fitted with a
nozzle 70. Owing to the fact, that the tar, or the petroleum residues, as the
case may be, directly meet the red-hot coal inass, as it moves along from plate
to plate in the tower, any caking of the coal residue resulting from decomposi-
tion, and its adhesion to the stationary supports, are avoided and a rapid and
complete gasification of the tar etc. is secured:
The coal residue, freed from gas, on leaving the shot tower 46, passes over
a discharging device arranged coaxially with the tower and serving to distribute
the coal residue uniformly among three out of four gas producers forming a
group, while access to the interior of the fourth generator, which happens to
be in the heating up stage at the time, is prevented by any suitable cut-off
device. As stated above, this discharging or distributing arrangement and the
cut-off device may vary in construction, the arrangement represented in the
drawing being, however, preferable. From the funnel-shaped orifice 49 of the
tower, the material passes into a shot pan 55, adapted to be raised and lowered,
and provided with an annular groove as a means of ensuring hermetic sealing,

page_text: within which pan there revolves the distributing cone 50. The latter is held
by a rotary supporting structure or frame 53, 54, divided into two halves held
together by screw-bolts. Rotary motion is imparted by means of toothed gear-
ing 51 and 52 (51 being a pinion and 52 a toothed rini). 56 is a rim for the
supporting structure to travel upon, and 67 a ball bearing working in oil. The
annular groove is filled with water and serves for cooling the guiding rim, with
the structure supporting the distributing cone travelling upon it. The pan 55,
which may be raised and lowered as stated, rests upon the carrying spindle 59,
which is mounted in the frame 60 provided with an internal screw-thread. The
frame 60 is mounted upon a carriage adapted to run upon a railway 62.
72 is a
toothed rim, and 73 a pinion for raising and lowering the pan 55 by means of
the spindle 59.
The distributing mechanism above described has the great advantage of being
readily accessible, whenever there happens to be any occasion for repairs, or
whenever any irregularity occurs in the operation. Also, as its operative parts
are situated outside, they can at all times be readily watched or inspected, whilst
in operation.
From the pan 55 the material is conducted, through the agency of the dis-
tributing cone 50, and through the shoots 58, to the water gas generators, and
divided among them in the manner stated. The water gas sweeps along the
tower and through the retorts in the upward direction, and, as it does so, effects
the extraction of gas from the new material and the gasification of the tar.
The gases escaping from the water gas producer in the heating up stage are
utilized for the external heating of the retorts in the manner described above,
they being conducted from the generators, over the dust collectors and through
the escape flues 64,-by the shortest way,-into the heating jackets 65 serving
for the retorts 42.
As compared with the employment of a single long retort, which the hot gases
emanating from the gas producers enter directly, the method of dividing the
retort into a number of short sections or lengths, arranged one below the other,
and combined with a shot tower, affords the additional advantage that, in this
arrangement, the transporting screws are less injuriously affected by high tem-
peratures, and one screw conveyor which is at all likely to wear off somewhat
rapidly, viz., that of the lowermost retort, can be readily removed and exchanged.
The process, which, in regard to details, is not confined to the forms herein
described but may, for instance, be carried out by means of stationary retorts,
differs from the methods of gas manufacture hitherto generally adopted by the
following advantages:-it effects, as far as practicable, a maximum saving in
the cost of labour; it saves the fuel usually required for external heating of the
retorts; it ensures the full utilization of the heat from the red-hot coke, from
which the gas has been extracted-which heat is lost in the ordinary processes;
its yield in gas as compared with that of the best methods hitherto known is
very high (viz., per ton of coal, about 1500 cubic metres of gas mixture of over.
3000 thermal units) and lastly, it admits of an easy carburization of the gas.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, I declare that what
I claim is:
1. The process for the complete gasification of coal and other carbonaceous
material, which consists in partly gasifying the carbonaceous material by the
direct action of the heat of highly heated water gas admitted from water gas
generators, this operation being continued until the residue approximately corre-
sponds to the coke produced in the manufacture of illuminating coal gas, then
transferring the red-hot residue thus obtained to. the water gas generatora and
converting it into water gas, with or without carburization of the latter by
injecting into the generators. hydrocarbons simultaneously with the steam, sub-
stantially as described and for the purpose specified.

page_text: 2. Gas generating plant comprising in its construction one or more revolving
retorts (5), each being provided with a stuffing box (2), transporting screw (3),
feed hopper (6), and guide ribs (7), a group of water gas producers (9) mounted
at a lower level near the discharge end of the said retort or retorts, a coke
distributing appliance situated over the centre of the group of water gas pro-
ducers and adapted to distribute the residual product of the retort to the gas
producers, and a scoop (8) adapted to guide the carbonaceous material from the
discharge end of the retorts to the said distributing appliance, the whole being
constructed and adapted to operate substantially as described, with reference
to Figs. 1 to 5.
3. In a gas generating plant of the type described, the combination of a series
of retorts (42) placed one above the other and communicating with each other
alternately in front and at the back and containing transporting screws 43, with
a shot tower 46 communicating at the top with the lowermost retort and at the
bottom with discharge shoots 64 leading to the water gas generators, the interior
of the said shot tower being provided with distributing plates 47 and the top
with a tank 66, substantially as described and for the purpose specified.
4. In a combined retort and water gas plant of the type described, the com-
bination of a circular group of water gas producers, with a distributing appliance
chiefly consisting of shaft 10, distributing cone 11, paddle wheels 12 and circular
casing 14 having projections 13 and recesses 15, substantially as described with
reference to Figs. 1 to 5, also the modified distributing appliance described with
reference to Figs. 6 and 7.
.
5. In a gas generating plant of the type described a distributing apparatus
with annular cooling and sealing device inserted between the lower end of the
shot tower 46 and the conduits 64 leading to the gas generators, chiefly com-
prising a rotary distributing .cone 50, a vertically moveable shot pan 55 resting
on a supporting spindle 59, and a stand 60 mounted on a truck running on
rails, substantially as described.
6. Apparatus for the manufacture of illuminating or heating gas from car-
bonaceous material consisting of gas retorts, water gas generators and accessories,
constructed and adapted to operate substantially as described. .
Dated this 4th day of April 1900
FAIRFAX & WETTER,
Agents 37 and 39, Essex Street, Strand, London.
FAIRFAX & WETTER,
Agents 37 and 39, Essex Street, Strand, London.