Improvements in Regenerative Gas Furnaces and Producers.
Year: 1889

page_text: Date of Application, 16th Mar., 1889
Complete Specification Left, 16th Dec., 1889-Accepted, 18th Jan,, 1890
PROVISIONAL SPECIFICATION.
Improvements in Regenerative Gas Furnaces and Producers.
1. FREDERICK SIEMENS, of No. 12 Queen Anne's Gate, Westminster in the
County of Middlesex, Engineer do hereby declare the nature of this invention to
be as follows:-
Regenerative gas furnaces for metallurgical purposes and melting glass have
hitherto been constructed with detached gas producers placed at a distance from the
furnace, and with two pairs of regenerators to each furnace, working alternately for
heating the inflowing gas and air and abstracting the heat from the products of
combustion, the flame entering and leaving the heating chamber through two sets of
separate gas and air ports in communication with the two pairs of regenerators
controlled by reversing valves.
It has been suggested that in such furnaces the regenerators for heating the gas
might be dispensed with, but unless rich gas is used, similar to the natural gas which
is available in America, or oil gas etc., the working of furnaces constructed in
accordance with this suggestion has not been attended with success, owing probably
to the inflowing gas into the furnace not being sufficiently hot.
Regenerative gas furnaces have, however, been constructed and successfully worked
provided with two regenerators for air only and their reversing valves, the gas, from
gas producers built near to or between the regenerators, being delivered hot in a
continuous stream. into the heating chamber by one port near to which two other
ports are provided serving alternately for the inflowing air and for the outflowing
products of combustion.
Regenerative gas furnaces have also been constructed in which the hot gas flows
continuously from one or more ports into the heating chamber where it meets with
heated air also flowing continuously from one or more ports in communication with
regenerators, which in this case act by transmitting heat from the outgoing to the
inflowing currents through brick walls instead of being of the reversible type as
above referred to.
My present invention consists in constructing a regenerative gas furnace provided
with air regenerators of the reversible type also with two separate sets of gas
and air, or flame, ports and with gas producer or gas producers placed as near as
possible to the Heating Chamber. The flue, or flues, bringing the gas to the Heating
Chamber is or are provided with means for feversing the direction of the current in
the furnace, and the regenerators are also provided with a reversing valve or its
equivalent for reversing the direction of the. inflowing air to the Heating Chamber
and of the outflowing products of combustion.
In this furnace, the Gas Producer may be provided with a grate or grates, or the
lower portion of the fuel may rest on a solid hearth; also air injection by artificial
means may be employed.
Instead of supplying air at the bottom of the Producer, products of combustion
from the Heating Chamber of the furnace may be admitted, in which case a steam
jet or other means must be employed for introducing such gases to the Producer; or
sometimes air and sometimes products of combustion may be admitted to the gas
Producer, the furnace working more economically in the latter case.
Dated this 16th day of March 1889
ABEL & IMRAY,
Agents for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in Regenerative Gas Furnaces and Producers.
I FREDERICK SIEMENS, of No. 12, Queen Anne's Gate, Westminster in the County
of London, Engineer, 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:-
Regenerative gas furnaces for metallurgical purposes and melting glass have hitherto
been constructed with detached gas producers placed at a distance from the furnace
and with two pairs of regenerators to each furnace working alternately for heating
the inflowing gas and air and abstracting the heat from the products of combustion,
the flame entering and leaving the heating chamber through separate sets of gas
and air ports in communication with the two pairs of regenerators, controlled by
reversing valves.
It has been suggested that in such furnaces the regenerators for heating the gas
might be dispensed with, but, unless rich gas is used, similar to the natural gas which
is available in America, or oil gas etc. the working of furnaces constructed in
accordance with this suggestion has not been attended with success, owing probably
to the inflowing gas into the furnace not being sufficiently hot.
Regenerative gas furnaces have, however, been constructed and successfully worked
provided with two regenerators for air only and their reversing valves, the gas, from
gas producers built near to or between the regenerators, being delivered hot in a
continuous stream into the heating chamber by one port near to which two other
ports are provided serving alternately for the inflowing air and for the outflowing
products of combustion.
Regenerative gas furnaces have also been constructed in which the hot gas flows
continuously from one or more ports into the heating chamber where it meets with
heated air also flowing continuously from one or more ports in communication with
regenerators which in this case act by transmitting heat from the outgoing to the
inflowing currents through brick walls, instead of being the reversible type above
referred to.
My present invention consists in constructing a regenerative gas furnace provided
with air regenerators of the reversible type, also with two or more separate sets of
gas and air, or flame, ports and with a gas producer, or gas producers, placed near to
the heating chamber. Each flue that brings the gas to the heating chamber is
provided with means for reversing the direction of the current in the furnace, and
the regenerators are also provided with a reversing valve, or its equivalent, for
reversing the direction of the inflowing air to the heating chamber and of the
outflowing products of combustion.
In this furnace the gas producer may be provided with a grate or grates, or the
lower portion of the fuel may rest on a solid hearth; also air injection by artificial
means may be employed.
Instead of supplying air at the bottom of the producer, products of combustion
from the heating chamber of the furnace may be admitted, in which case a steam
jet, or other means, inust be employed for introducing such gases to the Producer;
or sometimes air and sometimes products of combustion may be admitted to the gas
producer, the furnace working more economically in the latter case.
Fig. 1 of the accompanying drawings is a longitudinal section on the line a a of
Fig. 2 which is a sectional plan on 6b of Fig. 1, of a furnace according to my
invention.
Figs. 3 and 4 are vertical sections on c c and d d respectively of Fig. 1, and
Fig. 5 is a sectional plan on line e e. of Fig. 1. A is the bed of the furnace, B B.are
the two regenerator chambers, in this case situated below the producer C, which is
placed close to the furnace. On opening either of the valves V V, the hot gases from
the producer pass by one of the two ports D to one of the combustion chambers E E
where they meet with the heated air rising by one of the flues F F from the

page_text: regenerator B, which is then receiving air admitted to it through the reversing
valve W having attached to it a regulating damper plate w.
The flame sweeps round the furnace and the products of combustion pass by the
other of the flues F to the other regenerator B and thence by the reversing valve W
and the opened damper X to the chimney flue G When the one of the
regenerators B has become partly cooled by the passage of air through it, and the other
has become heated by the issuing products of combustion, the valves V and W are
moved so as to reverse the direction of the flame in the furnace and the action of the
regenerators, in the usual manner of operating with regenerative gas furnaces.
From the two spaces H, which intervene between the producer and the flame ports
of the furnace, I provide passages K (furnished with caps, by which they can be
closed) to the space L below the producer C. In each of the passages K. I arrange
a steam pipe which can direct a jet into the space I. During the time that the
products of combustion from the furnace A are passing by one of the flues F to one
of the regenerators, the passage K on the same side of the furnace is opened and its
steam jet is put in action. A portion of the products of combustion, instead of
passing down the flue F, is thus drawn by the injector action of the steam jet
through the space H and directed into the space L under the producer. As the
products of combustion consisting mostly of carbon-dioxide and nitrogen pass
through the incandescent fuel in the producer the former takes up an additional
portion of carbon whereby it is converted into combustible carbonic oxide, which
passes with the other produced gases to the furnace. M. and m are doors giving
access to the producer for clinkering and cleaning the grates. The caps to the
passages K being closed and the doors M m being opened, or the doors M m being
closed and an auxiliary steam jet, or jets as shewn at K¹ being provided, for the
admission of air to the spaces L under the grates, the furnace can be operated
without passing any of the waste gases through the gas producer as described.
Figs. 6 and 7 shew a similar arrangement of furnace with the regenerators B B
situated on each side of the producer C instead of being placed below. Fig. 6 is a
vertical section on ff Fig. 7 through the producer and regenerators, and Fig. 7 is a
sectional plan on qq Fig. 6..
In this
Fig. 8 is a longitudinal section of a furnace having a long bed A with a set of
producer, regenerators, passages and valves at each end of the bed, forming two
complete sets of gas producers, regenerators &c. for heating one chamber.
case the ignited gases form two horse shoe, or semicircular flames in the furnace
chamber. The products of combustion are drawn. away at each end of the furnace
chamber A by the flues F partly to the regenerators B and partly by the jets in the
passages K to the spaces Lunder the grates of the producers; but, instead of so
working the furnace, one jet K to each producer may be made to inject products of
combustion into the space I, under the grate, as shewn on the left hand side of
Fig. 8, while the other may be made to inject hot air rising from the regenerator
under the same grate, as shewn on the right hand side of the same figure; or one
gas producer may be supplied with products of combustion and the other with hot
air rising from the regenerator; or, again both gas producers may be supplied with
hot air alone from the regenerators.
Fig. 9 is a section on h h of Fig. 10 which is a sectional plan on of Fig. 9 of a
glass tank furnace A with producer, regenerators, passages and valves arranged as
above described, with reference to Figs. 1 to 5 inclusive.
Fig. 11 is a longitudinal section on of Fig. 12 which is a sectional plan on nn
Fig. 13, of a furnace with wide producer so arranged that the flame is directed from
either end of the furnace bed to the other. Fig. 13 is a section on m m of Fig. 12
shewing the gas producer and heating chamber in transverse sections.
Fig. 14 is a longitudinal section shewing a modified form of furnace heated by
flame from either end, there being a producer C.at only one end, with a passage N,
for the produced gases, which is shewn above the crown of the furnace, but
may be placed elsewhere. As shewn in this figure, the gas producer may be

page_text: supplied with air drawn from below the bed of the furnace by ineans of the steam
jet J.
Fig. 15 shews a form of furnace chamber with gas and air ports D and E partly
raised above the bed or siege A so that the flame delivered vertically or at an angle,
therein will afterwards take a horizontal or partly circular course to the..outlet
ports for heating by radiation as described in my Specification No. 5677 of: 1883.
which system can be applied with advantage to furnaces such as are herein
described.
In the drawings the reversing apparatus for gas is shewn as consisting of two
valves VV at the ends of a rocking beam, but other known forms of reversing
apparatus may obviously be employed.
In Fig. 14 a construction of furnace is shewn with, one outlet from the gas
producer leading to two valves V. V; but in other cases where one outlet from the
gas producer is adopted it may be preferable to use a flap reversing, valve or one of
some other pattern.
Instead of employing a steam jet for injecting products of combustion, or air,.
under or into the producer a jet of compressed air may be used, or mechanical means
may be employed; to create the required, currents, and such means may be used.
separately or some of them conjointly for the purpose of injecting either products of
combustion or air or both.
Although in the drawings I have shewn the flame ports as rectangular mouths
of horizontal flues for the air and gas, meeting the one above the other, in the
furnace chamber, they may be made of other forms or other arrangements of flame
ports such as are usually employed in regenerative gas furnaces may be adopted.
Also, instead of heating by one flame running the whole length of the furnace
chamber or sweeping round therein, there may be two or more flames, more or less
parallel to each other in each chamber controlled by one or more sets of valves; or,
as shewn in Fig. 8, there may be two semicircular flames issuing from opposite sides
or ends of the chamber.
In all the figures corresponding parts “are indicated by similar reference letters,
except where otherwise expressed.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what
I claim is
1. A regenerative gas furnace provided with air regenerators only and with a
gas producer near to the heating chamber the gas and air ports being governed by
suitable valves, some of them alternately admitting flame to the chamber, and one or
more of them discharging products of combustion therefrom, substantially as
described.
2. In combination with a furnace such as is above referred to a gas producer
provided with means of injecting air or products of combustion thereinto, sub-
stantially as described.
Dated this 16th day of December 1889