Improvements in the Utilization of Gas for the Combined Purpose of Heating Low Temperature Furnaces and the like, and Producing a High Temperature for Heating Steam Boilers, or other Purpose.
Year: 1899

page_text: .
Improvements in the Utilization of Gas for the Combined Purpose of
Heating Low Temperature Furnaces and the like, and Producing a
High Temperature for Heating Steam Boilers, or other Purpose.
We, AMBROSE BEARD, of 48, Windham Terrace, North Road, Wolverhampton,
in the County of Stafford, Iron and Steel Works Manager, and ALFRED EDMUND
BEARDMORE, of 365, New Hampton Road, Wolverhampton aforesaid, Chemist,
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:-
This invention has for its object means. whereby considerable economy of fuel
may be effected by the use of producer or other gas for the combined purpose
of heating a low (or comparatively low) temperature furnace, kiln or the like,
and producing a high temperature in a separate chamber for the purpose of rais-
ing steam, or for other purpose.
The above object is accomplished, according to this invention, by first burn-
ing the gas with a limited supply of air and utilizing the products of slow or
imperfect combustion to heat the low (or comparatively low) temperature furnace,
kiln or the like, and carrying the gases from such furnace, kiln or the like, to a
separate combustion chamber where they are burned with a further supply of air
which has, preferably, been heated such as by the heat of the low temperature
furnace, or kiln, and introducing into such second combustion chamber also a
supply of live gas which is burnt with the gases from the low temperature fur-
nace or kiln. The heat of combustion in the second chamber is at a high tem-
perature, and is utilized in raising steam in any convenient form of steam boiler,
or for other purpose for which a high temperature is required.
In order that the invention may be the better understood, we will describe the
same more in detail, and by way of example, as applied to heating furnaces for
iron or steel sheets, bars or black plates, and in doing so will refer to the accom-
panying drawings, which shew, also, by way of example, a method of utilizing
the heat from a second or high temperature combustion chamber in heating a
steam boiler.
Figure 1 is a sectional elevation, taken, as regards the left hand half thereof,
in the planes indicated by the line of Figure 2, and, as regards the right hand
side thereof, in the planes indicated by the lines yy of Figure 2, Figure 2 is
a vertical section taken on line a¹¹ of Figure 1; and Figure 3 is a sectional plan
through one of the low temperature furnaces, taken in the plane indicated by
line yy of Figure 2. The section shewn by the right-hand side of Figure 1,
and the section shewn by Figure 2, are somewhat conventional, for the sake of
greater clearness than would be afforded by true sections in the planes indicated

page_text: by the lines along which the sections are said to be taken. In Figure 2 the
boiler is omitted, for the sake of clearness of illustration.
"
The drawings illustrate two low temperature furnaces and corre-
sponding high temperature combustion chambers, and a vertical tubular
steam boiler (which is shewn, by way of example, as of the "Cook
type) adapted to be heated by the products of combustion from the high tem-
perature combustion chambers.
Each low temperature furnace A has a combustion chamber B3 which is divided
from the heating chamber C by a fire-bridge D, as is usual with this kind of
furnace; but the combustion chamber is filled in, except for the upper portion
thereof where the gases collect, with chequer brickwork. The producer gas, or
other gas, is brought through a pipe E into the lower portion of the combustion
chamber B, being brought in conveniently through the bottom of the back wall a
thereof, as shewn. Air flues bb, which are open at the front end of the furnace
run therefrom at a short distance below the middle of the bottom of the heating
chamber C, and are continued under the bridge D, and under the bottom of the
combustion chamber, and are formed with openings c through the bottom of the
combustion chamber. Air is, consequently, drawn through the flues and open-
ings into the bottom of the combustion chamber, and such air, being heated
on its passage through the hot flues, reaches the combustion chamber B consider-
ably raised in temperature, and mingling with the gas supplied through the
pipe E causes a partial or incomplete combustion sufficient to raise the heating
chamber to the required temperature for the purpose for which the furnace is
used. The products of partial or incomplete combustion pass out from each heat-
ing chamber C through flues d, which open out one from each side of each
chamber near to the forward end thereof and some distance above the bottom of
the chamber, and these flues from each heating chamber, respectively, communi-
cate with a flue e which itself communicates with a corresponding high tempera-
ture combustion chamber F. A pipe G supplies producer or other gas to each high
temperature combustion chamber F. Air flues ff, which are open at the front of
each furnace and pass therefrom under the bed of the heating chamber C, com-
municate, through short vertical flues g, with a transverse fluch formed within
the corresponding heating chamber C immediately at the front face of the fire-
bridge D, and this transverse flue h communicates with an upward flue i formed
in the brickwork of one side of the heating chamber; and a flue k communicates
between the flue and the corresponding flue e. The flue k communicates with
the corresponding flue e at a point which is nearer to the corresponding high tem-
perature combustion chamber F than that at which the corresponding flues d
communicate, and the flues d from a heating chamber may be cut off from the
corresponding high temperature combustion chamber F (the low temperature fur-
nace being, consequently, damped down) by means of a damper 7 which cuts off
the flues d without cutting off the air flue k. The air which passes through the
flues f, g, hi and k becomes considerably heated by the hot brickwork of the fur-
nace, and enters the combustion chamber F, consequently, at a considerable tem-
perature, and mingling with the gases from the flues d (when permitted to do so)
completes the combustion of such gases. The excess of air required for com-
pleting the combustion of the gases from the flues d, or the whole of the air pass-
ing through the flues fghik (if the flues d are cut off from the combustion
chamber F) is utilized in the combustion of the live gas entering the combustion
chamber F through the pipe G.
The products of combustion passing out from the high temperature combustion
chambers F are utilized to heat the boiler H.
The flow of the air and gases through their respective passage-ways, or flues, is
indicated by the arrows.
The high temperature combustion chambers F are filled in with chequer brick-
work, and the flow of gas through each pipe G into a high temperature combus-
tion chamber is regulated by a valve or damper m,

page_text: The boiler and high temperature combustion chambers are shewn, in the
arrangement illustrated, to be carried upon a platform I which is supported by
girders K and stanchions L.
If the heating chambers C are required to be at a higher temperature than
that of an ordinary low temperature furnace or muffle, such as when, for instance,
the heating chambers are for use for heating blooms, billets or the like, a greater
quantity than otherwise of heated air is supplied to each combustion chamber B.
This is conveniently effected, in the case of each furnace, by the use of additional
air flues nn which run under the bed of the heating chamber and communicate
through short vertical flues with a transverse flue o formed immediately below
the flue h and communicating, through an opening P, with the combustion
chamber B. The flues n are open to the atmosphere at the front end of the fur-
nace, and the air- which is drawn therethrough is heated on its passage through
the hot brickwork and enters the combustion chamber at a considerable tem-
perature. The combustion in this case being, of course, less partial than when a
less quantity of air is supplied to a combustion chamber, the escaping gases from
the corresponding heating chamber are not of the same value as fuel, and a corre-
spondingly greater supply of producer or other live gas needs to be supplied
through the pipe, G to the corresponding high temperature combustion chamber.
Air for the combustion of the gas may be supplied in any convenient manner,
either in lieu of or in addition to the methods, or either of them, above described.
The position of the high temperature combustion chambers, in relation to the
low temperature furnaces may, of course, be varied as required, as also may the
position and character of the boiler; and in some cases only a single high tem-
perature combustion chamber may be used, in combination with one or more low
temperature furnaces.
The gas may be utilized for slow or imperfect combustion, to produce a low
(or comparatively low) temperature, in the cases also, of furnaces, kilns or the
like, generally, in which a low temperature only is required, such as furnaces
for heating copper ingots, bars and sheets, close-annealing metals, burning
bricks and other earthenware goods, and such like purposes; and subsequently
with a further supply of gas for the purpose of producing a high temperature
for raising steam or for other purpose. The detail arrangements may have to
be varied to some extent to suit different kinds of furnaces, kilns or the like, but
the description above given in relation to heating furnaces for iron or steel sheets,
bars or black plates, and in relation to furnaces for heating blooms, billets and
the like, will indicate the character of the arrangements which will be generally
applicable for furnaces, kilns or the like, in connection with which the inven
tion is applied.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what
we claim is:-
1. Improvements in the utilization of producer or other gas for the combined
purpose of heating a low temperature furnace, kiln or the like, and producing a
high temperature for heating a steam boiler or other purpose, which comprise
burning the gas with a limited supply of air, utilizing the products of slow or
imperfect combustion to heat the low temperature furnace, kiln or the like, and
burning the gases from such furnace, kiln or the like, in a separate combustion
chamber with a further supply of air, and with a fresh supply of producer or other
live gas, substantially as described.
2. Improvements in the utilization of producer or other gas for the combined
purpose of heating a low temperature furnace, kiln or the like, and producing a
high temperature for heating a steam boiler, or other purpose, which comprise
burning the gas with a limited supply of air, utilizing the products of slow or
imperfect combustion to heat the low temperature furnace, kiln, or the like, and
burning the gases from such furnace, kiln, or the like, in a separate combustion

page_text: chamber with a further supply of air and with a further supply of pro-
ducer or other live gas, the air used in the combustion being heated by passing
through flues formed in the brickwork of the furnace, kiln, or the like, substan-
tially as described.
Dated this 1st day of March 1899.
STEPHEN WATKINS & GROVES,
Wolverhampton, Agents for the Applicants.