IMPROVE- MENTS IN AND RELATING TO GAS GENERATORS, AND IN GAS BURNING FURNACES CONNECTED WITH THEM
Year: 1880

page_text: LETTERS PATENT to Carl Pieper, Civil Engineer and Patent Agent, of
74, Belle-Alliance-Strasse, Berlin, S.W., Prussia, for an Invention of "IMPROVE-
MENTS IN AND RELATING TO GAS GENERATORS, AND IN GAS BURNING
FURNACES CONNECTED WITH THEM." A communication from August Kloenne,
Engineer, of Dortmund, Prussia.
PROVISIONAL SPECIFICATION left by the said Carl Pieper at the Office of
the Commissioners of Patonts on the 22nd March 1880.
CARL PIEPER, Civil Engineer and Patent Agent, of 74, Belle-Alliance-Strasso,
Berlin, S.W., Prussia. "IMPROVEMENTS IN AND RELATING TO GAS GENERATORS,
AND IN GAS BURNING FURNACES CONNECTED WITH THEM." A communication
from August Kloenne, Engineer, of Dortmund, Prussia.
This Invention relates to improvements in gas-generators and parts connected
therewith, as also to the furnaces in which the generator-gases are to be burnt,
special regard being had to the mode of combining the generator with a retort-
furnace or a steam boiler.
When gas-retorts are to be heated by generator-gases, the generator is placed
under the retort-chamber. It is constructed as low as possible, and is made to
project as far upward into the said chamber as the retorts will allow. For this
purpose the generator is by preference provided with a pointed or parobolic.arch,
the lower retorts are placed as far as possible apart from each other, and the lower
flues under these retorts are, or may be, shifted towards the outer walls of the
furnace. The charging orifice of the generator is by preference arranged in its
front wall. The air requisite for converting the fuel into carbonic oxyde enters
through an opening near the bottom of the generator. The arch above this opening
is kept cool by means of an iron or other tube or channel through which water,
steam, or air circulates, and is thus protected against any destructive influence of
tho slags.
The generator-gas passes from the generator through openings in the roof of the
latter into the retort-furnace, and here meets with the air requisite for its com-
bustion, which is supplied by suitable channels. The air by preference at first
passes through channels placed along the sides of the generator, and is thence
conducted by branch channels to the points of combustion. For the sake of proper

page_text: distribution of the air, there may be one main channel more on one side than ou
the other, or the air may be caused to enter into the channels on one side from the
front, and on the other side from the rear.
The branch channels lie inside of the retort-chamber or furnace, and on the roof
of the generator. They are constructed out of thin fire-proof bricks of suitable
shape.
In front of the generator there is a recess or pit for the fire man, which may be
closed by balanced flap-doors. If the generator is to be built on wet ground, it is
advantageous to provide the same with an inverted arch at the bottom.
The described arrangement of generator may also be used with furnaces of steam-
boilers or of other apparatuses requiring to be beated.
In small gas-works it may be advantageous to combine the generator with two
chambers, each containing one or two retorts, and cach communicating separately
with the generator, the chimney-flue, and a third retort chamber. This arrange-
ment allows the heating of one, two, or three chambers, as may be desired.
The air which has to be supplied to the generator may be heated by means of a
heating apparatus placed in a flue which conducts the combustion-gases from the
furnace to the chimney.
In some cases it is advantageous to arrange the channels supplying air for the
combustion of the gas in such a manner that these channels communicate with
each other alternately in the middle and at the ends.
Instead of using a channel through which water passes for keeping certain parts
of the generator cool, the latter may be arranged with a suitable grate and an ash-
pit adapted to contain water,

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Carl Pieper in the Great Seal Patent Office on the 20th September
1880.
CARL PIEPER, Civil Engineer and Patont Agent, of 74, Bello Alliance Strasse,
Berlin, S.W., Prussia. "IMPROVEMENTS IN AND RELATING TO GAS-GENERATORS,
AND IN GAS BURNING FURNACES CONNECTED WITH THEM." A communication
from August Klönne, Engineer, of Dortmund, Prussia.
This Invention relates to improvements in gas-generators and parts connected
therewith, as also to the furnaces in which the generator-gases are to be burnt,
special regard being had to the mode of combining the gas-generator with a retort-
furnace or a steam-boiler.
On the annexed Sheet of Drawings a retort-furnace containing six retorts for the
production of lighting-gas, and combined with the improved gas-generator, is
represented in different sections. The lines on which the sections are taken are
shown in the Figures.
The gas-generator K is placed under the retort-chamber, and by preference in its
center-line. It is constructed as low as possible, and is made to project as far
upward into the said chamber as the retorts will allow. For this purpose the
generator is, by preference, provided with a pointed or parabolic arch; moreover,
the two lower retorts are placed as far as possible apart from each other, and the
lower flues L, L, which have hitherto been located under the middle of these retorts
are or may be arranged close to the outer walls of the furnace. In this manner
a large combustion chamber is obtained, and also sufficient room between the lower
retorts as to allow the crown of the generator to be raised above the floor-line and the
charging orifice M to be arranged in the front wall of the furnace or the generator.
If prefered, however, this orifice may lie in the level of the floor. The air requisite
for the partial combustion of the fuel contained in the generator (i.e., for its
conversion into carbonic oxyde) enters through the opening N. For the purpose of
cooling the arch above this opening and of preventing it from being destroyed by
the slags produced by the combustion of the fuel in case they should have a
tendency to attack and melt the bricks, or when special fluxes are used, a tube or
channel O of cast iron or other metal is arranged on the inside face of the arch, and
through this tube or channel water, or if preferred air or steam, is made to pass by
means of suitable feed- and discharge-pipes. The said channel may however be
arranged inside of the brick-work which forms the arch.
The generator-gas passes through the openings P, P, into the retort-furnace, and
here meets with the air supplied by the channels h, h. This air enters from the
outside into the channels a and d, thereupon circulates on one side in the channels t
and c; on the other side in the channels e, f, and g, and is finally conducted by the
branch-channels h, h, to the points where the combustion of the carbonic oxyde gas
takes place. In consequence of the arrangement according to which there is on one
side of the furnace one horizontal channel more than on the other side the advantage
is attained that all points of combustion receive a nearly equal quantity of air. In
case, for instance, the distribution of air from channel c, Fig. 4, should be such that
the front branch channel h receives more air than the rear branch-channel, the
supply from channel g through its rear branch-channel will, on the contrary, be
greater than through the front one. The entire quantities supplied to the different
combustion points will therefore be nearly equal. The same object may, however, be
attained with an equal number of horizontal channels on either side of the furnace,
if on one side the air is admitted from the front, on the other side from the back
into the channels a and d. These channels may however be arranged otherwise if
preferred, or their number may be varied.

page_text: Within the channels a, b, c, and d, e, f, g, the air is heated to a certain extent;
but mainly this takes place in the branch channels h, which lie inside of the retort-
chamber or furnace. These channels are built upon the arched roof of the generator
out of thin fireproof bricks of special shape, as may be seen from Fig. 2. The air
being thus raised to a high temperature before meeting with the gas the heat
developed by the combustion is very intense. It may also be observed that no
combustion of gas takes place within the generator as is the case in certain other
furnace arrangements, and that therefore the temperature inside of the generator is
comparatively low. For the purpose of preventing an accidental ignition of the gas
inside of the generator by the flame passing downward through any one of the
openings P, these are made sufficiently small so as to cause the pressure in the
generator to be slightly higher than in the retort chamber.
In front of the generator there is a recess or pit R for the fire-man, who from
time to time has to clear out the slags collecting at the bottom of the generator
near the opening N. The said pit is provided with flap-doors, to which counter-
balance weights are attached, so that they may be opened and closed wich facility.
Sliding doors may however also be applied. By this arrangement the construction
of a vault under the floor, which would otherwise be required, is rendered
unnecessary; and the slags may easily be thrown out of the pit. The fireman also
keeps his head above the floor, and is therefore less exposed to heat and to the
influence of noxious gases. When the said doors are closed the retorts may be
attended to as usual.
The generator may be built with an inverted arch at the bottom, as shown in
the Drawing, for the purpose of keeping off any underground water. The arch
which forms the roof of the furnace is, by preference, made of elliptic shape,
especially when the furnace contains six retorts arranged in the manner represented
in Fig. 1, as this form is the most suitable for the purpose.
The described location of the lower retorts close to the outer walls of the furnace
yet presents the advantage over the common arrangement, that the gas discharge-
pipes may be connected with the retorts without any bend or elbow (see Fig. 1), in
consequence whereof the cleaning of those pipes is facilitated.
Although in the preceeding a furnace with six retorts has been mentioned only,
the described system of combining the generator with the furnace may, with slight
modifications, be adapted to furnaces containing any other number of retorts.
When eight or nine are used it is advantageous to apply two rows of gas orifices P,
between which channels for admission of air are located. With twelve retorts
three rows of gas-orifices will be found suitable, whereas one row is sufficient when
the number of retorts does not exceed seven.
I am aware that a furnace arrangement presenting some similarity with the one
described in the foregoing has been set forth in the Specification of the German
Patent, No. 31, granted to G. A. F. Liegel. It is however to be observed that,
according to this Specification, air is admitted into the chamber containing the
fuel, and immediately above the latter, so that tho gas generated is burnt within
the said chamber, which is therefore not to be considered a gas generator but an
ordinary furnace with a secondary admission of air. In the present arrangement,
on the contrary, there is no combustion of gas within the generator. The difference
between the two constructions is however yet founded on other points besides the
one specified.
The described construction of generator may also be used with furnaces of
steam-boilers or of other apparatuses requiring to be heated, it being only
necessary to adapt the same in every instauce to the special requirements of the
case.
Considerable advantages have already been obtained with the said gas firing
arrangement as well in respect to economy of fuel as in the quantity of lighting-
gas produced.
In small gas-works it may be advantageous to combine the generator with two
chambers, each containing one or two retorts, and each communicating separately

page_text: with the generator, the chimney-fluc, and a third retort chamber. An arrangement
of this kind in which each chamber contains one retort is shown by Figs. 5, 6,
and 7. The lower chambers Q and Q' communicate respectively by the holes P
and P with the generator by the openings n and n' with the upper chamber Q³,
and by the channels m and m with the chimney-flue S, while the channel m³ leads
from the chamber Q to the flue; and are the channels for the admission of
air. If one retort, for instance, the one in the chamber Q, is to be heated only, the
hole P¹, the channel, and the openings n and n' are closed, whereas the
channel m, the hole P, and the channel are opened. For the purpose of heating
the retorts of the two chambers and Q, m is closed, and n and m³ are
opened, &c. By this combination one or two retorts may be kept in reserve in
chambers more or less heated; these retorts may therefore always be put into
operation after a very short time, and with but small expenditure of fuel for
previously heating them to the required degree.
The Figures 8 and 9 represent a similar furnace with five retorts whose
arrangements allows the heating of two, three, four, or of the whole set of five
retorts, as may be desired.
The air to be supplied to the combustion-points P is heated according to Figs. 5
and 6, partly in the channels 1, 2, 3, on one side, and 1, 2, 3, 4, on the other side,
and partly in a series of pipes arranged within the flue S, and communicating with
the said channels.
The air required for the generator may also be heated by means of a heating-
apparatus placed in a flue or channel, which conducts the combustion gases from the
furnace to the chimney. An arrangement of this kind combined with channels
for heating the air for the combustion of the gas is shown in Figs. 10 and 11. The
combustion-gases pass from the fluo L into the flue L'. In this flue a pipe or a
series of pipes U is placed, which communicates with the generator, and within
which the air serving for maintaining the combustion in the latter is thus heated.
Instead of the pipes U the series of pipes arranged in the flue S may however also
be used for heating the air to be conducted to the generator, suitable connecting
pipes only being necessary for this purpose.
The air by which the combustion of the gas is to be produced enters by the
channel 1, is heated in the channels 2, 3, and 4, passing along the sides and bottom
of L, and is thenco conducted by channel 5 and the branch channels to the
combustion-points P. There may be, in this case, one air-channel more on one side
than on the other, as in the first described furnace.
According to the arrangement shown in Figs. 12 and 13 the air-channels
communicate with each other alternately in the middle and at the ends. The
manner in which the air circulates in this case will be seen clearly from Fig. 13.
It was however impossible to show the channel 4 in this Figure, as will easily be
understood by following the course of the lino N, O, Fig. 12, on which the section
Fig. 13 is taken. By the described construction of channels a uniform distribution
of air to the different points of combustion is obtained, as well as with the one
described with regard to Figures 1 to 4, but the air may enter in the same
direction on both sides of the furnace. In some cases this arrangement may
present advantages in the construction.
Fig. 14 shows a modification of the generator, in which the latter is provided
with a grate while the ash-pit is recessed at the bottom, so that it may contain
water. The steam generated from this water by the ashes which fall into the
same, and by the heat radiating from the grate, is decomposed while passing
through the burning fuel, so that hydrogen gas is produced, which is subsequently
burnt in the furnace together with the carbonic oxyde. The water and the steam
serve also to keep the lower parts of the generator sufficiently cool, in consequence
whereof special arrangements for preventing the arch above the opening N of the
ash-pit from being melted (such as the above-described channel O) may be dispensed
with.
Having thus described the nature and object of this Invention, and the manner

page_text: in which it may be carried out in practice, as communicated to mo by my
correspondent, I hereby claim as new and important features of the same,-
1. The gas-generator K placed below a retort-furnace, a steam-boiler, or other
apparatus requiring to be heated, the arrangement being made in such a manner
that the air required for the conversion of the solid fuel into carbonic oxyde enters
by an opening N in the front or lateral wall of the generator, while the points of
combustion P of the carbonic oxyde are immediately above the arch of the same,
substantially as and for the purpose specified.
2. The combination with the arch above the opening N of the generator of one
or more channels O made of metal, through which water, steam, or air circulates,
as and for the purpose described.
3. The transverse branch-channels h constructed within the combustion-chamber
of the gas, and built of fire-proof bricks of special shape; these channels serving
for the purpose of heating the air while they conduct the same to the combustion-
points P, substantially as described.
4. In combination with the described furnace the pit R, provided with balanced
flap-doors, as hereinbefore specified.
6. In a retort-furnace the arrangement of the lower flues L close to the lateral
walls of the furnace, as described and for the purpose stated.
6. The arrangement of the charging orifice M in the front wall of the generator.
7. In combination with a gas-generator of the kind described, an inverted arch
at the bottom of the same, for the purpose herein before stated.
8. The combination with the gas-generator K, Figs. 5, 9, of the two chambers Q
and Q', cach containing one or two retorts, and each communicating by separato
apertures with the generator, the chimney-flue, and a third retort-chamber Q, as
and for the purpose described.
9. The combination with a gas-furnace provided with a generator K of a pipe or
a series of pipes arranged in a flue, which conducts the combustion-gases to the
chimney, such pipe or pipes serving to heat the air which causes combustion either
in the generator or in the furnace, substantially as hereinbefore specified.
10. In combination with a gas-furnace provided with a generator K, the
arrangement of a number of channels supplying air for the combustion of the gas,
and which communicate with each other altornately at the middle and at the ends,
as described with reference to the Figures 12 and 13.
11. In a gas-generator K when combined with a retort-furnace, a steam-boiler,
etc., the arrangement of a grate with steps, below which water is maintained in the
recessed ash-pit, as described and for the purpose set forth.
In witness whereof, I, the said Carl Pieper, have hereunto set my hand and
seal, this Eleventh day of September, in the year of our Lord One thousand
eight hundred and eighty.