Improvements in or relating to Regenerative Furnaces.
Year: 1897

page_text: Date of Application, 14th June, 1897-Accepted, 14th June, 1898
COMPLETE SPECIFICATION.
Improvements in or relating to Regenerative Furnaces.
A communication from FRANZ WÜRTENBERGER, of Sestri Ponente, in the
Kingdom of Italy, Mining Engineer.
I, ALFRED JULIUS BOULT, of 111, Hatton Garden, in the County of Middlesex,
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 follow-
ing statement:—
The present invention relates to a special construction of a regenerative or
Siemens-Martin furnace which enables the temperature of the gases entering the
furnace maintained is within such limits that the disadvantageous and wasteful
dissociation of the generator-gas which according to observation has hitherto
occurred in the gas chambers is completely done away with whereas on the con-
trary the temperature of the air in the air chambers is brought to the highest
maximum attainable which has a very favourable effect on the good working of
the furnace.
In order to express in degrees the different temperatures aimed at it can be
stated that the gas the temperature of which at the gas inlet valve is, on the
average about 300° C (572° F) is heated in the gas chamber to about 700° C
(13920 F) while the air the original temperature of which is about 30° C (86° F)
is heated to the highest maximum possible, that is, to about 1300° C (2372° F)
or more. In order that the gas may be heated only very little and the air on the
contrary as much as possible the number and volume of the gas chambers are
made different from the number and volume of the air chambers. The interior
of the air and gas chambers is moreover arranged in a different way and lastly
there is arranged a suitable device for regulating the heating that is the amount
of the waste heat entering the chambers.
In the accompanying drawing,
Fig. 1 is an irregular horizontal cross section of the improved regenerative
furnace, on the lines u-u, vw, x, y, z, Fig. 2.
Fig. 2 a vertical cross section on the irregular line a bed of Fig. 1.
Fig. 3 a vertical section on the line n o of Fig. 2.
Fig. 4 a vertical section on the line p q r of Fig. 1.
Fig. 5 a vertical section on the line I m of Fig. 1.
Fig. 6 a vertical section on the line ef of Fig. 4.
Fig. 7 shows a slightly modified construction of the furnace in horizontal cross
section.
In Fig. 8 the left hand half is a vertical section of Fig. 7 on the line a-b, the
upper part of the right hand half being a similar section on the line e, f, g, & the
lower part a section on the line c-d of that figure.
Fig. 9 a vertical section on the line no of Fig. 7 and
Fig. 10 a vertical section on the line p q r s t u of Fig. 7.

page_text: number of the chambers used namely the number of air chambers in the present
invention is twice that of the gas chambers, there being all together 4 air
chambers (I II III IV) but only 2 gas-chámbers (V VI). Further each air
chamber has a much greater capacity than each gas chamber.
While using the 6 chambers the regenerative furnace can be formed in
different ways it being however preferable to arrange the chambers in side by
side with their longitudinal axis normal to the longitudinal axis of the furnace
(direction of the flame).
With regard to the different possible constructions of the furnace the two gas
chambers (V and VI) may for example either be arranged separately from the
air chambers I II III and IV so, that the latter alone form the foundation of the
furnace as in Figs. 1 to 6 of the drawings, or the 6 chambers of the regenerative
furnace may together form the solid foundation of the furnace as shown in
Figs. 7 to 10.
It must be however pointed out that the main characteristic feature of the in-
vention does not consist in the particular constructions illustrated, but in the
combination of air chambers with only half the number of gas chambers of the
constructions shown the one, mentioned first in which the air chambers alone form
the foundation of the furnace is considered more suitable than the second in
which the 6 chambers together form the foundation of the furnace.
Each of the 4 air chambers I II III IV is provided at the top towards the metal
chamber of the furnace with a flue so that 4 flues are formed marked in the
drawings A1 A2 A3 A4 (Fig. 2) further at the bottom of the air chambers I II III IV
there are provided flues B1 B2 B33 134 which lead to the air-inlet and reversing valve,
the flues B1 and B2 B3 and B' merging together near the air reversing apparatus
so as to form single flues 135 and B6 (Fig. 1). Near where the flues merge together
each of the four flues B1 B2 B3 B is provided with a valve (v³ 2d 2-5 2001).
The two gas chambers V and VI which are separated from the 4 air chambers
form a space whose cross sectional area and volume are much smaller than those
of the air chambers. The gas chambers V and VI communicate at the top in
the usual way by means of flues C₁ and respectively with the metal chamber E
of the furnace. At the bottom of said chambers V and VI flues D' and D² lead
to the gas-reversing apparatus.
The second characteristic feature of the invention consists in the interior
arrangement of the two different kinds of chambers above referred to. The air
chambers are filled in the usual way with refractory stones or material in order
to form in these air chambers a mass capable of absorbing and giving off great
quantities of heat whilst the gas chambers on the contrary are only provided with
a series of superposed arches forcing the gas entering said chambers to follow a
zig-zag path and also confining the melting and the formation of slag to the upper
part of the gas-chamber. For this purpose the upper arch of each chamber V
and VI is provided with a space C3 and C4 respectively in which the slag collects.
Lastly with reference to the new method of regulating the admission of the
heat from the furnace to the chambers it is effected by a combination of 4 valves
for the air chambers with only 1 valve for the two gas chambers.
The air valves 23242526 are arranged in the flues which lead from the air
chambers to the air reversing apparatus close to this latter. The valve for
regulating the admission of waste heat into the two gas chambers is however not
arranged as hitherto in the passage or flue leading from the gas reversing
apparatus to the chamber but on the contrary it is arranged in a separate passage
or flue F branching off from the gas reversing apparatus A.
In the present case where the main object in view is to keep the temperature
of the gas chambers different from that of the air chambers it would be wrong to
arrange the valve in the passage between the gas chamber and the gas reversing
apparatus for in such case said valve would have to be lowered very much during
that period of working during which the waste heat taken from the chambers in
order to allow only a little heat to pass into the gas chambers but much heat into

page_text: the air chambers. On the contrary the valve would have to be fully open during
the period in which the hot gases enter the chambers, because hot gases require
a great space owing to their expansion under heat.
To avoid this drawback it was found advisable to arrange a separate heat regu-
lating passage or flue (F) leading from the gas reversing apparatus to the main
chimney and to arrange in said passage or flue F a regulating valve or damper 22
which in the present case suffices for both gas chambers.
The passages are therefore arranged so that at first there are separate super-
posed passages F and G starting from the two reversing apparatus A and B, Figs. 4
and 6, the air flue G being arranged underneath and its cross section being much
larger than that of the upper gas flue F separated from the air flue by an arch I
and containing the regulating damper 2. From the damper 2 the arch separat-
ing the two flues continues a little further and then the two flues combine in one
flue H (Fig. 1) the damper v¹ being arranged in this combined flue.
As will be seen in the drawings the improvements above described are embodied
both in the furnace shown in Figs. 1 to 6 and in that shown in Figs. 7 to 10 and
it will be evident that said improvements can be applied to all furnaces of the
regenerative kind whatever be their shape or direction of the flame.
Having now particularly described and ascertained the nature of the said
invention as communicated to me by my foreign correspondent and in what
manner the same is to be performed I declare that what I claim is :-
1. In a regenerative furnace regenerators consisting of four air-chamber and
two gas-chambers the latter being either combined with the former to form the
lower portion of the furnace or arranged separately from the the air chambers
in which case the lower portion of the furnace consists only of the four air
chambers the longitudinal axis of the air chambers being arranged at right angles
to the direction of the flame in the furnace substantially as described and for the
purpose specified.
2. In a regenerative furnace waste heat regulators consisting of two valves v³ v
or arranged in the air supply passages and a valve in a separate flue for
regulating the heating of the gas chamber substantially as described.
3. In a regenerative furnace the construction of a flue by means of two super-
posed passages leading from the two reversing apparatus the regulating valves v
being arranged in the upper one leading from the gas reversing apparatus sub-
stantially as described.
4. In a regenerative furnace the construction of a gas chamber consisting of
several superposed arched partitions which force the gas to follow a zig zag path
substantially as and for the purpose described.
5. The combination and arrangement of parts constituting the complete
regenerative furnace substantially as described and illustrated in Sheet One or in
Sheet 2 of the accompanying drawings.
Dated this 14th day of June 1807