Improvements in Coke Ovens.
Year: 1891

page_text: Date of Application, 21st July, 1891
י
Complete Specification Left, 21st Apr., 1892-Accepted, 21st July, 1892
PROVISIONAL SPECIFICATION.
[Communicated from abroad by Dr. THEODOR BAUER, of Bülowstrasse, 31,
Berlin, W., Director, and GEORGE MENDHEIM, of Munich, Bavaria, Civil
Engineer, both in the German Empire.]
Improvements in Coke Ovens.
1, HENRY HARINGTON LEIGH, Assoc. M. Inst. C.E., Fel. Inst. P.A.,
practising as Phillips & Leigh, at No. 22, Southampton Buildings, Chancery
Lane, in the County of Middlesex, Engineer and Patent Agent, do hereby
declare the nature of this invention to be as follows :—
My invention relates to improvements in the construction of coke ovens worked
with or without extraction of the by-products. It consists in a novel combination
of oven, counter current air heating chambers through which the products of com-
bustion are led for the purpose of abstracting a substantial percentage of their
remanent caloric and transferring it to the fresh air supply destined to effect the
combustion in the combustion chambers of the gases evolved by the dry distillation
maintained in the coking chambers. The temperature to which the said air
currents is raised is sufficiently high to prevent them abstracting caloric from the
coking chambers. The resultant combustion is therefore as sufficient and thorough
as it can be and much more economical either in respect of quantity or quality of
heating gas consumed and yields better results in respect of the quantity of coal
coked by the given quantity of gas.
The present invention is applied to horizontal plant of ovens worked without
the extraction of by-products as follows.
"
Troughs are formed in the top of the oven and over the coking chambers which
extend across the plant. The coal, are dropped from the waggons into these
troughs and thence through suitable openings or throats at short distances from
each other vertically into the chamoers where they are pressed down by suitable
tools worked through the said throats. There are exit flues for the gases at each
end or side of a chamber near the top in its side walls and these per set deliver into
a transverse flue commo. to that set and from thence the gases flow through
suitable flues into chanr.els where they are met by a highly heated air supply,
flowing upwards out of ertical dues. Combustion is at once established.. Suitable:
spyholes are provided through which the progress of the combustion can be
watched. The flames ass down vertical flues intermediate to those last mentioned.
and thence into, flues ing under the soles.of the coking.chambers, thence through:
suitable ports and vertical flues into horizontal flues near the top of the oven:from t
which they descend through vertical flues into horizontal flues the floors of which
alone separate them from the horizontal air heating chambers. The flames or gases
now flow downwards through vertical pipes or tubes fixed in the air heating
chambers in the well known, manner.. They next flow into the main exhaust flue on
their way to the chimney. In the flue from the vertical pipes there are dampers:
applicable to each coking chamber. The exhaust may be further utilised as may
be desired or may be practicable before it reaches the chimney.
The air supply flues are some vertical and some horizontal. They deliver into
the air heaters at or near the bottom thereof. The air currents then flow to and
through a horizontal grid iron arrangement of pipes into a collecting channel from
which they flow into the first mentioned vertical flues on their way to meet the
gases from the coking chambers.
The air heaters are built up of bricks perforated in two directions both vertically
and horizontally. The number of perforations is according to the temperature to
which the air currents are to be raised.

page_text: The coking chambers on, say, the left hand of an installation deliver their com-
bustible gases to the right. The air supply from the air heater of the first chamber
is led to the left hand and in the case of the last to the right hand, but in the case
of the, say, two central chambers the gases and the air supplies are led in both
directions.
If it is desired to save the by-products the gas exit flues at the top of the coking
chambers are closed after the plant has got well into work by suitable devices
provided in the next or transverse flues and capable of being adjusted from the
outside. The gases will then flow into a special or collecting pipe leading to
the separator. The return gases from the latter flow into the flues near the top of
the plant above the level of the vertical flues through which the heated air supplies
flow. Suitable cocks are provided to regulate the said pipes.
In applying the present invention to a plant of vertical coke ovens the procedure
is as follows
The coking chambers are arranged in lines one on each side of the longitudinal
centre of the plant, and have arc shaped backs and soles. Down the said centre
runs the air-heater, i. e., between the two ranges of coking chambers which
accordingly stand at right angles with it.
The distilled gases from the coking chambers pass through suitable flues at the
top of the chambers into a horizontal combustion flue above the range of the latter
where they meet the hot air currents from the heater. The flames flow from this
flue into others beneath it and in front of the coking chamber so as to jacket the oven
against loss by radiation, and into the flues or chambers interspacing the coking
chambers. A damper is provided to regulate the area of the communication
between the horizontal combustion flue and the flues interspacing the coking
chambers.
Part of the flame or hot gases from a pair of the said interspacing flues flow
through side flues into the arched flue behind the respective coking chamber and
rising upwards behind it passes through a short transverse flue into horizontal flue
above the air heater, through which latter it flows downwards parting with the
major portion of its heat on its way and thence into the exhausts.
The main air supply channels communicate with the atmosphere at the ends of
the plant and are arranged in the lower level of the latter. The supplies flow
upwards through branch channels to the lower part of the air heating columns,
through horizontal and vertical pipes and passages therein suitably interspersed
with baffles through suitable horizontal flues into the combustion flue or chamber.
For the purpose of regulating the flow of hot air there are numerous vertical
openings from the top into the said horizontal flues through which suitable flue
stoppers can be introduced, or other equivalent devices can be used. Flue stops may
also be applied to either of the lateral flues leading from the interspacing com-
bustion chambers into the arc flue behind the coking chamber as well as at the top
of the last mentioned flue.
When a plant as just described is to be worked so as to yield the by-products,
the flues leading from the tops of the coking chambers are stopped and the said
products led into suitable valve-controlled flues into main pipes leading to the
separator from which the volatile combustible portions are. then returned to
the plant.
Dated thie 21st day of July 1801

page_text: The drying and preliminary heating of the oven is effected as heretofore; and in
describing hereinafter its construction and operation, it is assumed that the oven
has already been heated, and is being operated by the direct gases of the coking
chambers without the extraction of the bye-products. For charging the
chambers A, A, the coals are discharged from the trucks into the gutters b
whence they pass through the apertures a, a, a, into the chambers, where the coal
is pressed down by means of suitable tools worked through the said openings. The
latter are arranged close to each other so that the work of charging the chambers
up to the top is much facilitated and simplified.

page_text: The products of the dry distillation escape through the apertures c, c, c.
These
are arranged at the two ends of the oven. They lead into the flues d' or d
respectively, and pass through the apertures e, e into the flues f', where they are
met by highly heated air currents from the vertical flues g, 9, 9.
Combustion is
established, the development and temperature of which can always be observed
through the sight holes h³, h³.
Through the flues i, i, i and the apertures k, k, k, the flames pass into the flues
and underneath the sole of the chamber, from thence through the apertures m, m
into the flues n, n, and upwards into the flues o¹ and o², flowing thence downwards
through the flues p, p and g, g into the fluer or r² as the case may be. The soles
of the latter are furnished by the air-heaters B₁ and B respectively. Passing
through the vertical flues s, s, of the latter, the escaping flames impart to them
continuously a portion of the heat still remaining in them after they have passed
through the flues i, n, p, q, l, and 1, which serves to heat the charges of coal.
From there they flow into the flue t'and through the apertures u into the flue C
leading to the chimney. In the aperture u, the draught of each chamber can be
regulated at will by means of the respective slide which is accessible from the
corridor D.
If desired, the products of combustion may be led through the flue C to a boiler
or to the hearth of a drying kiln before they pass into the chimney. The air
necessary for the combustion of the gases from the coking chambers comes partly
through the pipes wl, wl, and partly through the pipes w³, w³. From them it flows
to the lower part of the air-heater, through the horizontal pipes x, of the latter
which are underneath the plates y and then through the horizontal pipes of the
air-heater arranged underneath the plates y², y and y. The current flows finally
through the pipes arranged above the plate y' into the small collecting channel =
and from the latter into the flues g. The latter are made of peculiarly shaped
bricks and lead upwards between the walls of the chamber and the flues of the
same to the combustion-chamber.
The different peculiarly shaped bricks which are perforated in two directions and
of which the columns of the air-heater are constructed are illustrated on an
enlarged scale in Figs. 6, 7, 8 and 9.
The number of peculiarly shaped bricks placed one above the other to form
the column of the air-heater, and how many times the air supply to be heated
is to flow through the columns by means of the horizontal tubes, are considerations
dependent upon the degree of heat to be given to the air-supply.
It may happen that the air in lieu of passing 6 times as illustrated in the drawings,
flows only 4 times or even only twice through the column; and, on the other
hand, it may be advisable to cause the air to pass 8 times, or even still oftener. At
all events, the temperature of the air in the air-heater B must be so high that in
passing through the flues g, g, it does not take up heat from the walls of the
coking chamber or at least only a very small quantity.
From the sections T-U, V-W, and Y-Z.-Fig. 2-it will be seen that the
chamber on the left hand discharges the combustible gases developed in it into the
flues on the right hand; that likewise, in the first chambers, the air which is heated
in the corresponding air-heater arranged underneath the said chambers, is led to
the left hand and in the last chambers to the right hand, but that from two
chambers located about in the central part of the plant, the gases developed therein
as well as the air heated in the air-heaters arranged underneath the said chambers,
are conducted on both sides into the flues on the right hand as well as to those on
the left hand, one of which therefore receives simultaneously the gases from two
chambers and the air from two air-heaters.
These central chambers work, of course, a little more weakly than the adjacent
ones, but this inconvenience is less important than it would be if the said chambers
were located directly at the ends of the range, the operation of which is
unfavourably influenced by a more intense radiation of heat, viz.-from the front.
walls of the oven.

page_text: become together with their flues, red hot, whereupon they are charged in the
regular way. If, at the same time there are by-products to be extracted from the
distilled gases, the apertures c, c, c are closed, after a few chambers have been
charged, by means of small flue plates provided for this purpose in the flues d¹, d².
These are pushed from the front part of the flues by means of a suitable tool, in
front of the said apertures c, c. The gases then flow through the iron tube 1, 1
fitted to the aperture a¹, and through the valve 2 into the collecting pipe 3, leading
to the scrubber or condenser. The same circulation that causes the gases to pass
through the scrubber forces the non-condensed portion of them into the con-
duits 41, 42, whence they flow through the branch pipes 6,6 into the flues d' and d².
The cocks 5, 5 serve to regulate their flow. The gases pass then from the said
flues & and a through the flues through which the gases which flowed direct from.
the apertures c, c, e previously passed.
THE COKING CHAMBERS.
A, A, A are the coking chambers. They are arranged in two ranges between.
which is located the air-heater B'.
To utilize directly the products of the dry distillation which goes on in the
chambers A, A, they are directed through the apertures a¹, a' at 6into the flue_c²
where they are ignited with the highly heated air supply from the air-heater B¹..
As the flame is compelled to pass from the flue c' through the two apertures d', d'
and then to descend, the part of the chamber located the nearest to the outer wall
of the oven takes the largest portion of the heat of the flame, for that part of the
chamber which is most exposed to the cooling influence of the outer air requires.
the largest quantity of heat. The larger part of the flame will pass preferably
from the flues d, taking the shortest way, vertically downwards through the
aperture e, as it is allowed to escape from the lateral aperture of the chamber only
through the flues f¹,ƒ³.
It may happen sometimes that this takes place more than is desired, through the
flame may penetrate through the flue g¹ also into the rear part of the.Hue į¹-
arranged underneath. To force, if required, the flame more through the apertures 9*..
and to increase by this means the heating of the rear parts of the chamber, use is
made of a slide or register k¹ for suitably restricting the passage e¹ whilst the
corresponding chamber is in operation.
Through each of the flues f¹, f, passes the half of the flame of each pair of
lateral flues into the flue behind the chamber, and, ascending the latter, passes
through the flue m' into the channel n¹, or n³, respectively above the air-heater.
It then descends through the vertical pipes o, o, o parts to the said air heater with
the larger part of its heat, and, lastly, flows through the channels p', q', and p³, q²,
to the chimney D, outside the oven body.
The air-supply is conducted through the branch channels s, s, s from the
channels, open at the two ends (but which may also be closed if required)
to the lower part of the air-heating columns, and flows thence through the
horizontal pipes 1, 1 and the intermediate spaces 1', 1' which are underneath the
plates 2, and from thence through the horizontal pipes of the air-heater arranged
underneath the plates 21, 22, 23 and 24 for entering finally through the pipes
arranged underneath the plate 24 of the air heater the passages 3, 3, 3 leading to.
the corresponding flues between the coking chambers or to the flues arranged on
the ends of the said chambers.
In order to reduce, if required, the admission of heated secondary air supply to
certain flues, or to shut off the same entirely when repairs are to be made in certain
chambers, a peculiarly shaped brick is arranged in each passage.3, the horizontal
escape opening t' of which may be restricted at will or be entirely closed. .Owing
to the accessibility of the opening from-above, these regulations may be effected

page_text: with a sufficient exactness, even while the oven is at work, so as to obtain the
desired effect with certainty.
Each flue m' may be closed by inserting at 4¹, a slide or register, and the
corresponding chamber may be separated from its secondary chambers and from
the air-heater by closing the flues at f¹ and f².
When by-products are to be extracted at the same time from the gases from
the coking chambers, the apertures a¹1, a³, which are easily accessible from above, as
may be seen from the drawings, are closed by means of suitable bricks luted thereto,
and the gases are led to the condenser through the pipes u, the valves v and the
pipes w. The return gases, i.e., those returning from the condenser, where they
have deposited their by-products flow through the flue ' and its branches y' into
the flues through which the direct gases (i.e., the gases distilled in the coking
chambers) flowed on their way to the combustion chambers and flues.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. The combination of coking chambers of any construction with counter-current
air heating appliances, in which flames escaping from the flues of the chambers
give off by transmission by means of walls made of refractory bricks a portion of
their heat to the secondary air serving for the combustion of the gases employed
for heating the oven and the temperature of which is raised by the escaping flame
then no longer capable of directly heating the coking chamber, substantially as
set forth and shown in the accompanying drawings.
2. In a horizontal coke oven plant and in combination with counter current air
heating-appliances :
•
a. The arrangement at each end of the oven of a flue at a high level whence
the direct gases from the coking chamber, or the gases returning from the.
scrubber or condenser after the extraction of the by-products, pass in several
currrents into a lower channel into which penetrate from below several
currents of heated air:
b. The arrangement of heating channels in such a manner that the flame
produced by the direct gases from the coking chamber, or the said returning
gases, and the heated air, is introduced at the two ends of each coking
chamber of the plant into the first vertical heating flues, rises then upwards,
after having passed through underneath the sole, into the adjacent vertical
heating channels of the chamber, the products of combustion descending
thence downwards again through the vertical heating flues of the chamber
in the central part of its length, heating thus on their way the sole of the
oven;
c. In a coke oven plant the arrangement of flues in such a manner that those
which are located at each end of the plant between the corresponding last
chamber of the oven and the corresponding front wall are fed with the
whole quantity of air passing through the air-heater arranged underneath
the corresponding chambers and with the whole quantity of combustible
gases produced in the corresponding chambers by the process of dry distilla-
tion, the latter when direct gases are used and not gases returning from
the scrubber, but that, on the contrary, the heated air arriving from the
air-heater arranged underneath the sole, and the combustible gases produced
therein, when by-products are not extracted, are distributed to one of the
chambers located in the central part or near the central part of the plant
into the flues arranged on the two longitudinal sides of the chamber in
question and which do not receive either gas or air from any adjacent
chamber.
d. The arrangement in the arch of each chamber of a larger number of
charging holes disposed one close to the other in such a manner that they

page_text: may be closed by means of suitable bricks and that the whole charge may
rapidly be introduced and pressed down by means of suitable tools passed
through the said holes.
. In a plant of vertical coking chambers provided with counter current air
ting appliances:
a. The arrangement of a flue c' on the upper end of each chamber into which
are introduced the direct gases therefrom or the gases remaining after the
extraction of the by-products and burnt with the aid of air highly heated by
the counter-current air heater B ;
b. The arrangement of the heating flues in such a manner that the exterior
parts of the chamber of the oven which are the most exposed to the cooling
influence of the outer air come into contact with the hottest part and the
largest volume of the flames, so that the latter pass from the flue c' through the
flues, to a heating channel ' arranged on the side of the coking
chamber at a lower level, and from thence in a main current through an
aperture which may be regulated by means of a slide e and which is
applied to the front wall of the oven and in a secondary current through a
flue g arranged in the rear part into a heating channel disposed at a lower
level from thence through a flue on the front wall of the oven to a
heating channel underneath the sole of the coking chamber from the said
flue through a channel n¹ or n³ respectively above the air heater to the
vertical pipes o¹ of the latter whence it escapes through the channels p¹
and g' to the chimney:
c. The arrangement of an aperture in the air supply conduit which can be
regulated by means of a small refractory plate or entirely shut off, so that
when repairs are to be made one or more chambers may be thrown out
without interrupting the operation of the plant.
.
Dated this 21st dew of Anril 1909
HENRY H. LEIGH,
22, Southampton Buildings, Chancery Lane, W.C.
HENRY H. LEIGH,
22, Southampton Buildings, Chancery Lane, W.C.