Year: 1887

page_text: Date of Application, 30th Apr., 1887
Complete Left, 29th Feb., 1888
Complete Accepted, 29th Mar., 1888
I, GEORGE DOWNING, of 8 Quality Court, Chancery Lane, in the County of
Middlesex Patent Agent A communication from abroad by Theodor Bauer, of
Munich, Bavaria in the Empire of Germany, Civil Engineer do hereby declare
the nature of the said invention to be as follows:-
The object of my invention is to effect improvements in the construction and
arrangements of coke ovens, suitable for manufacturing coke from various kinds of
coals and coal mixtures; my invention also comprising arrangements for the effective
operation of the ovens, whether the bye products are extracted or not.
In carrying out my invention, I build and arrange the chambers in a circular group
round a central air receiver or channel at the bottom and round a gas main or
receiver at the top. These two receivers communicate with one another. The lower
receiver or channel contains a circular flue leading into the gas main, or upper
collector, and provided at its outlet with a number of perforations so as to form a
grating, allowing the hot air which surrounds it to enter the channel. The circular
Aue in the centre of the group is constructed with a channel communicating with
the outer air and adapted to convey back (when required) the gases treated for the
extraction of bye products, and of leading them into the main. The several air
channels converge radially towards the central air channel, and are arranged below
the combustion chambers. When the Coke ovens are operated without extracting
the bye products, the channel may, when required, serve for the admission of air,
and, after the construction of such ovens is completed, they may be utilised for
drying the inner masonry work by means of a small coke fire. During the period
of time that the gases are being exhausted some of the dampers are closed to
prevent the escape of the gases into the gas main and becoming mixed therein
with air. When the gases have arrived at the lowest point of the central passages
they are divided, and pass into the combustion chambers, through small divided flues,
they then ascend above the dumpers, one of which is provided to each combustion
chamber these dampers being arranged in a circle round the common shaft. All the
chambers are formed alike as regards their dimensions and their combustion spaces;
and they all operate under the same conditions. A group of ovens of this novel
construction is entirely independent of the apparatus used for the extraction of the

page_text: bye products, and it may therefore be worked at any time with or without the
addition of the extraction of such products. These ovens are also capable of operating
intermittently or at stated intervals of time if only the gases of the first and most
productive time in the evolution of the gases are treated when for instance the per-
carburetted hydrogen gases which contain most of the tar are being disengaged.
This first period may likewise be utilised for coals which are rich in gases and only
slightly bituminous, and which could not be treated in any other oven for the
extraction of the bye products, on account of the cost. These coals will always yield
sufficient tar to cover the working expenses of my improved ovens and apparatus.
Furthermore, the necessity of having duplex apparatus, for the extraction of bye
products, is, unnecessary as, in case of interruptions of working such extraction by
repairs or otherwise the oven continues to operate after the dampers are closed, in the
saine manner as any other oven from which bye products are not extracted. This
oven however operates better and more uniformly than other systems when even the
extraction of bye products is abandoned from the first. In the ovens hitherto used
with extraction of bye products, it has been necessary to withdraw, and also to cool,
the last gases produced which gases are the hottest, and contain the least quantity of
bye products. This causes a considerable loss of heat, which has to be replaced or
regenerated by means of large and costly Siemen's regenerators, whereas in my oven
such requirement does not exist. I am also enabled to dispense with a considerable
number of large and small return pipes as ordinarily used, as only one return pipe is
necessary Moreover, my improved construction has this advantage, that by using
coal rich in gases, and withdrawing the gases for short periods of time, a great
portion of the heat may be used for heating boilers, and for lighting purposes,
provided powerful burners are employed. My improvements are economical in
construction; and coke may be manufactured in these ovens with coal which could
not be profitably utilised in ordinary ovens.

page_text: Improvements in Coke Ovens.
I, GEORGE DOWNING, of No. 8, Quality Court, Chancery Lane, in the County of
Middlesex, Patent Agent, do hereby declare the nature of this invention, (a com-
munication from abroad by Theodor Bauer, of Munich, Bavaria, in the Empire of
Germany, Civil Engineer,) and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement :-
The object of this invention is to effect improvements in the construction and
management of coke ovens.
It consists in the combination of retorts; controllable gas-exits to the condenser ;
central gas collecting, and gas-and-air mixing chambers, arranged side by side or one
above the other; controllable gas flues from the retorts to said chambers; air supply
conduits; a return communication from the condenser to the said gas collecting
chamber; and air heating or refrigerating devices.
These improvements adapt the ovens for coking various kinds of coal, and of coal
mixtures; and also provide for the working of one entire oven in totality, or in part
only, and with or without communication on the part of any one or more of the
several retorts of said oven with the condenser.
I will now proceed to describe this present invention, as the same has been
communicated to me, in detail, referring in so doing to the accompanying drawings
which are to be taken as part of this specification and read as illustrations thereof.
It will be observed that I have selected a transverse sectional elevation, and a plan,
for the purpose of illustrating each type of the improved coke oven. Each plan is a
composite one; the respective sectors of which, as divided by the diameter lines
drawn through the figure, are plans corresponding with the levels Nos. 1. 2. 3, etc., as
marked on the respective elevations.
Figs. 1 and 2 illustrate the invention in a general way. The construction of oven,
as well as the relative positions and functions of the various parts shown in the said
figures, may bo taken by the reader, and are intended to be so taken, as embodying
the main ideas, and illustrating the substantive features of the invention. But it is to
be distinctly understood that this invention is not confined, in respect of the relative
positions of the various parts, to the exact construction illustrated in the said figures,
inasmuch as such positions, as well as other details, may be modified without
departing from the scope of the said invention.
Figs. 1 and 2 are, therefore, illustrations of the invention in a simple form; and
are inserted for the purpose of shewing its principal features; while the remaining
figures, riz. 3 to 10, are illustrations of four modifications or developments of
my invention, as shewn in such figures. Each one of these four modifications is
peculiarly adapted to the coking of some specific class of coal, or to the conduct of
the process of coking in some particular way.
Referring to Figs. 1 and 2, A are the chambers, or retorts, arranged radially in a
circular group around both a central, or annular, air-receiver, Z, and a gas main or
receiver, or gas collecting chamber, G.
Y is a circular flue establishing a communication between the air-receiver, Z, and

page_text: the gas collecting chamber, G. It is provided with a number of perforations, , so as
to form a grating which shall allow the hot air from the receiver Z, to enter the said
flue or channel, Y.
It may now be pointed out that the function of the air receiver being to receive the
air for combustion, and to deliver it to the gases escaping from the retorts, A, which
gases are collected in the chamber G, it is practically a matter of indifference whether
the said receiver, Z, and chamber, G, are, the former under the latter, or are arranged
so that the former is outside the latter. If the air-receiver is outside the gas collecting
chamber, the flue of communication, Y, will necessarily be replaced by horizontal
flues discharging the same function. B is the air-and-gas mixing chamber in which
the gases from the collecting chamber, G, and the air for combustion from the
receiver, Z, conmingle, before they pass through the ways, I, into the passages or
flues, J, behind and beneath the retorts, A.
These passages or flues, J, occupy a central position between the vertical axis of an
oven, and the exterior thereof; and communicate, right and left near the outer wall
of the oven, with the combustion chambers, D, interspacing the retorts, A, by means
of flues, j.
The several air channels, or conduits, C, converge radially towards the air
receiver, Z; and may be, advantageously, arranged in a plane immediately under
the combustion chambers.
All the retorts and combustion chambers are counterparts of each other respectively;
and operate under the same conditions.
The products of combustion pass away from the combustion chambers, D, into the
exhaust flue, K, past dampers, E.
His a flue leading from each retort, A, away to the condenser; and, F, a damper
controlling the flue leading from a retort to the gas collecting chamber, G.
G2 is a channel establishing a communication between the circular flue, Y, and the
outside, where it is connected up to a gas main leading back from the condenser.
It may also be used as a channel for the admission of combustion air when it is
not being used as a gas conduit from the condenser to the oven. It is also well
adapted to serve as a furnace for drying a new oven, by having a fire kept up in
it for the necessary time.
If it be desired to work the retorts, any or all of them in combination with the
extraction of the bye-products from the gases evolved therein, communication is
established between those retorts and the condenser via the flue, H, and shut off
between them and the gas collecting chamber, G, by closing the dampers, F. The
gases will then flow through the condenser, and, after having deposited the bye-
products therein, return to the gas collecting chamber, G, along the flue, G².
Figures 3 and 4 illustrate a coke oven of twelve retorts, constructed according to
this invention for coking fat coals. This construction is hereinafter referred to as
Type 1.
Figures 5 and 6 illustrate a coke-oven of twenty four retorts, constructed according
to this invention for coking middling fat coals. This construction is hereinafter
referred to as Type 2.
Figures 7 and 8 illustrate a coke oven of thirty retorts, constructed according to
this invention for coking non-caking coals-This construction is hereinafter referred
to as Type 3.
Figures 9 and 10 illustrate a coke oven of forty retorts, constructed according to
this invention, for coking lean coals, and supplying sufficient coke for one blast
furnace. This construction is hereinafter referred to as Type 4.
In each of the sectional elevations, Figs. 1, 3, 5, 7 and 9, the left hand balf is a
section through a retort and the right hand half a section through a combustion
chamber.
O
10

page_text: ',
m,
m: Vertical and lateral exhaust flues.
A coke oven constructed according to the present invention is adapted not only for
the production of coke from coals of different qualities, but also allows of the retorts
being worked with, or without, the condensation of the bye products. As a con-
sequence of this adaptability, duplicate condensers, for it must be borne in mind
that, up to the present time, it has been necessary to provide two condensers, one to
stand in reserve, and ready to be used in the event of a break down or of repairs,―
may be dispensed with and the cost of the plant lessened considerably.
"
Referring to a former invention of "Improvements in coke ovens by the Inventor
from whom I have received this communication; and for which Letters Patent,
No. 11040, dated 7th August, 1884, were granted; I wish to point out that the part
described in the Blue Book of said Patent as the "Contact Canal flues i" is replaced,
in the present invention, by an annular gas and air mixing chamber, which is
surrounded by ovens having curved bottoms.
All the gases issuing from the retorts, A, as well as those returning from the
condenser, (not shewn in any of the figures), meet in the said gas and air mixing
chamber, B, with the hot combustion air flowing along the air conduits, C, C1, C2
The lower part of the said mixing chamber, B, is provided with gratings, b, for the
purpose of equalizing the temperature of the air currents flowing into the chamber.
This gas and air mixing chamber is supplied continuously with gas and air; and all
the bottom and lateral Hues of the retorts are, therefore, supplied continuously and
equally with gas and air mixed ready for combustion. The combustion chambers, D,
interspace the soveral retorts, A, up to the level of the dampers, E; and all draw
upon the same source of heat of a high temperature generated by the free combustion
of gas and a proper volume of air.
The composition of these gases is varied. They either flow from the retorts, A,
past the dampers, F, direct into the gas collecting chamber, G, which is central in
Types 1 and 2, and annular in Types 3 and 4, or, if the retorts are being worked in
combination with the condenser, they then flow back from the condenser into the said
gas collecting chamber, G, through a suitable pipe, G', conveniently situated for the
discharge of its functions. This pipe is illustrated in Figures 7 and 9 as a circular
one on the top of the oven, but is not shewn in the other elevations.
It is in any case adapted to deliver the return gases flowing along it into flues G²,
leading to the said gas chamber, the position of said flues being near to the top, or to
the bottom of the oven, according to that of the return pipe, GY.
As each retort, A, is provided with its own separate complement of conduits, flues,
and dampers, all the retorts being arranged radially, and alternating the the com-
bustion chambers, D, it at once becomes apparent that any one or more of the retorts
of one oven can be kept in operation independently, of the others.
And not only can

page_text: any of the retorts of one oven be kept in operation independently, but, they, or any of
them, can be worked
a: Either without extracting the bye products in the condenser, if the gases set
free in the retort are allowed to flow direct therefrom into the gas chamber, G; or,
b: In combination with the extraction of the bye products in the condenser, by
using for the purposes of combustion, the gases returning from the condenser; or,
c: Both the said methods may be amalgamated; that is, a mixture of direct and
return gases; the former from the retorts, A, past the dampers, F, and the latter
through the flues, G³, may be used for the purposes of combustion.
Managers of gas works have now by the aid of analyses and long practical
experience established the fact that the most advantageous periods for the extraction
of the bye products precede the less advantageous periods in definite proportions.
It was easy to apply this knowledge in actual practice, but up to the present time
this has not been done.
The practical application referred to would have consisted in defining, so to speak,
the most advantageous period for the extraction of the byc products in a suitable
construction of plant adapted to allow of the several retorts being worked in shifts, as
may be required; and in saving the cost of a second or duplicate condenser, which
has always been required, to be used in the event of the one in use getting out of order.
The improved construction of coke oven which forms the subject of this present
invention solves the problem of the said practical application, and at the same time
allows of the use in the retorts, of coals containing only a small per centage of tar
and ammonical liquor.
In a coke oven constructed according to the said invention, it is possible to extract
a quantity of tar sufficient to cover the cost of working mixtures of 50% of anthracite
and 50% of caking coals. In the coke ovens in use up to the present time it has
been impossible to obtain a practicable coke from such mixtures as those just specified,
to say nothing of the extraction of any bye products.
Every competent engineer knows that the act of charging a retort with fresh coal
is soon followed by the development of so considerable a volume of gas, that flues,
constructed in view of a nominal quantity cannot contain it. Consequently, a certain
proportion is not burnt, because the act of charging necessarily involves a cooling of
the retort so long as the charging lasts, and this prevents the free development of gas,
and interferes with the supply of combustion-air.
The resultant incomplete combustion, and the partial syntheses which take place,
allow a large per centage of carbon to pass away through the flues, and up the
chimney unburnt. Coals whose composition inclines them to deposit soot, quickly
produce choking of the flues, and this is followed by a considerable cooling of the
retort, and the production of coke of an inferior quality.
In a coke oven constructed according to the present invention, the excess of gas
which is not drawn off into the condenser for the extraction of bye products passes
into the gas collecting chamber, G, the capacity of which suffices for the utilisation,
for the benefit of the entire oven, of the excess of gas periodically set free in one or
the other of the retorts.
The gases always surround the retorts, A, in unvarying volume and temperature,
with the result that the heating thereof is continuous and not interfered with during
the act of drawing the coke. Moreover, no cold air can flow by way of the retort into
the flues, inasmuch as the retort damper F, and the flue, H, to the condenser, are
always closed towards the end of the shift.
A retort has, excepting the door in front at which the coke is drawn, no more vents
than those just mentioned, so that it is impossible for a current of air through it to be
established when the said door is opened; and besides, the sliding of the mass of coke
downwards practically shuts off the upper part of the retort against the entrance of
cold air from the outside.
When its door is shut, a retort is a closed chamber; and if, from any cause, its
temperature should fall, it can be rapidly raised by the continuous circulation of the
burning gases, and the proper adjustment of the damper, E.

page_text: When any retort needs repairing, its damper, E, is closed, as are also those of the
two adjoining retorts whereupon the circulation of the combustion gases about the
said retort ceases while the remaining retorts of the oven continue to work as before.
The operation of a coke oven constructed according to the present invention is as
follows; and as tho construction of the four types is essentially identical, this
description applies in a corresponding degree to all.
The retorts, A, having been charged through the doors, A¹, the direction in which
the gases evolved from the coal undergoing the process of coking depends upon
whether they are to be subjected to the process of condensation before being burnt in
the combustion chamber, D, or whether they are to be passed into the latter direct
without previous condensation.
If they are to be sent through the condenser, communication between the retorts to
be tapped and the condenser pipe, H', is established; and the damper, F, closed.
After the gases have passed through the condenser, they are brought back through
the pipe, G, into the flue, G³, from which they flow into the gas collecting
chamber, G, into which they would have been passed direct from the retorts if the
process of condensation had been omitted.
Here they meet with the heated combustion air which has been admitted along the
various conduits, and C. This air has been heated in its passage by contact with
the hot walls of the regeneration or heat accumulator, viz, the walls of the exhaust
flues adjoining the air conduits. Gas and air mingle with each other in the mixing
chamber, B.
pro-
The hot gaseous mixture now flows from the mixing chamber, B, through the ways, I,
into the flues, J, behind and under the retorts; and up by way of the flues, j, into the
combustion chambers, D). It will be noticed that a special air-conduit, C², may be
vided for the purpose of supplying extra air to a combustion chamber if it be required.
The exhaust gases pass away from the combustion chamber past the dampers, E.
The passage of the gases from the gas and air mixing chamber, B, through the
openings, I, on to the combustion chamber, D, is the same in Types 1, 2, and 3.
The products of combustion flow past the dampers, E, into the main chimney, K,
which is provided in the centre of ovens of Types 1 and 2. In Type 3 this main
chimney must be constructed at the side of the oven, and if required one shaft may
serve for several ovens.
The gases from the combustion chamber of this latter type flow downwards through
a central vertical flue, L, from which they pass into lateral flues 1, 1, which are led
backwards and forwards between the air conduits C, C¹; their common walls, there-
fore, acting as a heat accumulator, or regenerator-to use the common expression,
for the air-currents flowing along the said conduits. From the lateral flues ', the
exhaust gases pass into the main exhaust, 1, communicating with the chimney, K,
are disposed of in any other convenient way.
ог
Type 1 has only one air conduit, C, for the gases have not long distances to travel;
and coals for which this type is intended are very prone to cake, and develope but
little gas while yielding a considerable quantity of coke.
In Type 3, the air conduits discharge into a common air chamber, 0³, situated
between them and the gratings, b, of the air and gas chamber, B, for the purpose of
adjusting the differences in temperature of the air currents entering by the said
conduits, as well as for assimilating the distribution of said currents.
It must be carefully borne in mind, that, in Type 3, only a few flues, G³, for the
entrance of the return gases are required, (say 4 to 6), and not one to each retort,
even if there should be as many as 30, for the return gases distribute themselves in
the gas collecting chamber, G, and the air-and-gas-chamber, B, and mix with
direct gases flowing past the damper, F, as well as with the heated combustion air
flowing from the chamber, C³.
Constant and practical experience, as well as the requirements of mine managers to
be able to turn out good results cheaply from lean coals and mixtures, as well as the
desire to be able to supply a blast furnace from one coke oven, (i.e., an output of from
60 to 70 tons every 24 hours), have led up to the elaboration of Type 4.

page_text: The oven illustrated in Figures 9 and 10 is 15 metres in diameter and has
40 retorts, each capable of receiving a charge of 2½ tons every 24 hours which
makes 100 tons for the oven.
The output varies according to the quality and composition of the coals or mixtures
used; or from 60 to 85 tons of coke every 24 hours; for the turnout from theso
ovens is almost equal to the theoretical quantity, as has been already proved by
practical use of them.
Coke ovens constructed according to the present invention are provided with a heat
accumulator adapted to extract the heat from the exhaust gases.
This extracting and heating goes on without reversing the draught, and without
costly regenerators.
The heat accumulator illustrated in Figures 9 and 10 is constructed within the
bottom part of the wall of the central chimney K. The air conduits, C, at the
top of the oven are led downwards, being expanded at short intervals into annular
chambers, e, to the base of the shaft, where they join the lateral air conduits, C. The
exhaust gases flow from the combustion chambers past the dampers, E, down the
flues, m, into the lateral flues m¹, and up the central chimney, K, therefore on both
sides of and close to the vertical air conduits, C,
The remainder of the construction of the several retorts and of the air and gas flues
of this Type 4 is, substantially, the same as that of Types 1, 2, and 3, already
described.
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 combination in a coke oven, the retorts of which are arranged radially
around a vertical centre common to all, of either a central or an annular gas
collecting chamber with an annular air-and-gas mixing chamber, and passages leading
from the former to the latter.
2. In a coke oven the retorts of which are arranged radially around a vertical axis
common to them all; the combination with said retorts, of flues led from the air-and-
gas mixing chamber downwards behind and under the backs and floors, respectively,
of said retorts, said flues being thereby adapted to lead the gas-and-air mixture from
the central part of the oven outwards, and to then deliver it into the combustion
chambers.
3. A central, or annular, gas collecting chamber adapted to receive the gases
flowing from retorts arranged radially around it, as well as the gases returning from
the condenser; substantially as described with reference to the accompanying figures.
4. The combination of radial retorts; central gas collecting chamber; controllable
flues leading from the said retorts, respectively, to the said chamber; and a gas flue
adapted to receive the gases returning from the condenser, and to deliver them into
the said chamber; substantially as described with reference to the accompanying
Figures 1, 2, 3, 4, 5, and 6.
5. An annular gas and air mixing chamber adapted to receive the gases from the
retorts, the gases returning from the condenser, either or both, and air for their
combustion delivered into said chamber through heated air conduits; in combination
with flues under the retorts, and air and gas ways adapted to lead the mixed air and
gas from the said chamber to the combustion chambers by way of said ways and
Blues; substantially as described with reference to the accompanying figures.
6. The combination of radial retorts; annular gas and air mixing chamber;
controllable flues adapted to lead the gases from the said retorts into said chamber;
a flue adapted to receive the gases returning from the condenser, and to deliver them
to the said annular mixing chamber; one or more air conduits under each retort
adapted to supply said annular mixing chamber with air for the combustion of said
gases; ways leading from the said mixing chamber into said flues; radial combustion
chambers interspacing the retorts, into which combustion chambers said flues under
the retorts are adapted to deliver the mixed gases and combustion air; and regulatable

page_text: exhausts adapted to heat the air conduits; substantially as described with reference to
the accompanying drawings.
;
7. The combination of radial retorts; a central or annular gas collecting chamber
annular gas-and-air-mixing chamber; controllable flues adapted to lead the gases
from said retorts into said gas collecting chamber; a flue adapted to receive the
gases returning from the condenser, and to deliver them to said annular gas
collecting chamber; one or more air conduits to each retort adapted to supply said
annular mixing chamber with air for the combustion of said gases; flues under
the said retorts; and ways leading from the said mixing chamber into said flues;
radial combustion chambers interspacing the retorts into which combustion chambers
said flues under the ovens are adapted to deliver the mixed gases and combustion-air ;
and regulatable exhausts adapted to heat the air conduits; substantially as described
with reference to the accompanying drawings.
8. The combination of radial combustion chambers interspacing the retorts with air
conduits adapted to supply air to said chambers, respectively, in the manner and
substantially as described with reference to Figures 5, 6, 7, 8, 9 and 10.
9. The combination, with a retort and its gas supply, of two air conduits adapted, by
their length and propinquity to hot exhaust flues, to heat the air currents flowing
through them; and an annular air collecting chamber adapted to receive the heated
air currents from said air conduits, in which chamber they become amalgamated
before passing into the gas-and-air mixing chamber substantially as described with
reference to the accompanying Figures 7, 8, 9, and 10.
10. The combination of vertical exhaust flue adapted to receive the gaseous
products of combustion from the combustion chambers, and lateral exhaust flues
adapted to lead said products away past the walls of the air conduits, substantially
as described with reference to Figures 7 and 8.
11. The combination of vertical central chimney flue; downward air conduits
formed within the wall thereof; annular expansions of said conduits; and lateral
air conduits led past the walls of lateral exhaust flues; substantially as described
with reference to Figures 9 and 10.
12. The combination with a retort, of a flue adapted to lead the gases developed in
said retort either towards the condenser, or to the gas collecting chamber, or gas-and-
air-mixing chamber; a valve and damper adapted to control said flue, and to,
consequently, direct the course of said gases either towards the condenser, or into the
said chambers; and a damper adapted to control the exhaust from the combustion
chamber for the purpose of enabling the several retorts of a coke oven to be used
together or separately, and in combination, or not, as may be desired, with the
condenser.
13. The general construction of coke ovens, and the process of operating the same,
substantially as described with reference to Figures 1 and 2.
14. The general construction of coke ovens of Type 1, and the process of operating
the same, substantially as described with reference to Figures 3 and 4.
15. The general construction of coke ovens of Type 2, and the process of operating
the same, substantially as described with reference to Figures 5 and 6.
16. The general construction of coke ovens of Type 3, and the process of operating
the same, substantially as described with reference to Figures 7 and 8.
17. The general construction of coke ovens of Type 4, and the process of operating
the same, substantially as described with reference to Figures 9 and 10.
D
301