Improvements in and connected with Furnaces for Burning Liquid Fuel.
Year: 1889

page_text: Date of Application, 11th Sept., 1889
Complete Specification Leit, 11th June, 1890-4ccepted, 11th Sept, 1890
DD
TLANT
Improvements in and connected with Furnaces for Burning
Liquid Fuel.
We CARL ADOLPH SAHLSTRÖM of No. 10, Colville Gardens, Bayswater in the
County of Middlesex, Engineer, and JOHN COLEY BROMFIELD of 49, Selborne Road,
Hove, in the County of Sussex, Civil Engineer, and ALEXANDER FRASER HILL of 9
Sackville Road, West Brighton in the County of Sussex Gentleman do hereby
declare the nature of our invention to be as follows:-
According to our invention the furnace is provided with one or more burners so
constructed that the fuel is blown or forced through same in a state of fine spray by
means of steam or air or both combined so that by a proper combination of the fuel
with super-heated steam and air of a proper temperature the highest possible heat is
obtained.
The supply of fuel, steam, or air is controlled by steam valve or otherwise so as to
be increased or diminished, each separately, at will.
The fuel is contained in a tank; and if this fuel consists of tar or other viscous
material a little heat must be applied to the tank in order to render its contents
perfectly fluid. The fuel is conducted from the tank to the burner by means of a
pipe so constructed at its mouth, for some of the contemplated purposes, that it passes
down the centre of a steam pipe forming the core of same and the steam pipe in its turn
is surrounded by an air jacket communicating with air pumps by means of which the air
may be forced if required. The mixture of air, fuel and steam in proper proportions
gives perfect combustion and a most intense heat.
For melting metals, glass &c. the ovens may be constructed as follows:-They
may be fixed or moveable. If fixed, the main structure is brick as customary, cased
or not with iron or other metal. In the interior of this brick-work is a chamber the
lower portion of which is widened to provide a passage for the circulation of the flame,
and in the case of melting large quantities of metal such as iron, this chamber is
filled with the material to be melted but in such a manner that the above described
passages are left free for the flame to circulate. When used for smaller quantities
or in those cases when it is necessary to keep the metal from direct contact with the
flame, this chamber is provided with an interior lining of fireclay or other fire
proof material having an orifice communicating with the exterior of the furnace
and supported in a suitable manner to bear the weight of the metals being melted.
There is a space between the lining and the chamber which is filled loosely with
balls of fireclay or other material through the interstices of which the flame passes.
Or instead of the lining a crucible may be used, in which case the upper part of the
open space may be filled with fire brick suitably fixed. The spent gasses are not
allowed to escape into the air but are utilized in preheating the crucibles, metals,
air, steam &c. required for use. In admitting the flame of the burner to the open
passage at foot of the chamber before described it is done (when one or two burners
are used) at a tangent and with a downward inclination in such a manner that the
flame comes into contact first with the fireclay or other filling material or the side of
the furnace before reaching the metal. The lower passage is also provided with
sight holes by which it may be seen that the proper regulation of the materials
forming the flame is attained. As a modification the lower portion of the interior
chamber immediately over the circulating passage previously described may be
fitted with fire brick in radial order to support the metal to be melted and having
interstices between them to allow of the passage of the flame and also to permit
the melted metal to descend into the receiver below. In this formn the widened
lower portion of the chamber is used as a receiver for the molten metal and has
no fire clay &c. balls as previously described. The flame is admitted as before
but impinges upon firebrick before coming in contact with the metals.
Pai 77

page_text: In the portable or moveable form, the apparatus is divided into two portions.
The lower part is preferably of hemispherical form, and may be used as the
receptacle for a crucible containing the metals to be melted; or may be used as
a crucible itself. If used as a receptacle for a crucible, the burner or burners are
fixed in this lower part in a similar manner to that before specified: and, in this
case, the upper portion of the apparatus, which is to be described presently is
made so that it can be lifted off or put upon the above mentioned lower portion.
If used as a crucible itself the burner or burners are preferably fixed in the top
compartment. This top compartment is somewhat cone-shaped and may contain
the coils or other means used for utilizing the spent gasses in heating the steam,
air and oil as already mentioned. The lower portion, used as a crucible, is provided
with means for attaching a crane &c. so that it can be carried to any required place,
tilted &c. The same system of burning liquid fuel may be used for heating steam
boilers and other purposes where an intense concentrated heat is not required, in the
following manner: The furnace is fitted with a dome of firebrick provided with
suitable openings for allowing the flame to come into contact with the boiler;
and is partly filled with pieces of firebrick or fireclay balls. If the latter are
used, in all cases wherein they are mentioned in this Specification they are preferably
pierced with a hole so as to expose a larger surface to the heat of the flame.
Below these pieces of firebrick or balls of fireclay, or in any other suitable place,
the coils or other means used for beating the oil, air, steam &c. are placed. The
burners are fixed in such a manner that the flame impinges upon the fireclay balls or
pieces of firebrick. It is not absolutely necessary, in this case, to force the air through
the air-jacket of the burner. When this method of firing is used in steam ships when
it is necessary to economize the fresh water in the boilers, the fuel can be forced into
the burners by means of compressed air, or steam preferably in the following manner :
The fuel is contained in one or more tanks, constructed in the same manner as the
boilers. Into the upper portion of the tanks compressed air, or preferably steam, is
forced, by which means the fuel is driven through the burner at a high velocity. The
interior of the fuel pipe of the burner is deeply rifled so as to give a rotary
motion to the stream of fuel and spread it on its exit at the mouth of the burner.
The pipe conveying the compressed air, or steam and which immediately surrounds
and encloses the oil pipe may also be rifled the volutes being in the same direction
or in a contrary direction to those of the fuel pipe. Or the same effect of spreading
the fuel into fine spray on its issuing from the burner may be produced by a
pair of fine platinum, or other suitable metal membranes between which the fuel
either with or without steam, or air is forced. Or, again, a rotating mouth piece
may be used to produce the required effect.
Dated this 11th dow'st Contamhan 1000
COMPLETE SPECIFICATION.
Improvements in and connected with Furnaces for Burning
Liquid Fuel.
'
We CARL ADOLPH SAHLSTRÖM of No. 10 Colville Gardens, Bayswater in the
County of Middlesex Engineer, JOHN COLEY BROMFIELD of 49 Selborne Road
Hove in the County of Sussex Civil Engineer, and ALEXANDER FRASER HILL of
9 Sackville Road, West Brighton in the County of Sussex Gentleman, 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:--
According to our invention the furnace is as hereafter described provided with one or
more burners so constructed that the fuel is blown or forced through same in a state

page_text: of fine spray by means of steam or air or both combined so that by a proper combin-
ation of the fuel with superheated steam and air of a proper temperature the highest
possible heat is obtained.
'The supply of fuel, steam or air is controlled by screw valve or otherwise so as to be
increased or diminished each separately at will.
.
The fue is contained in a tank and if this fuel consists of tar or other viscous
material a little heat must be applied to the tank in order to render its contents
perfectly fluid. The fuel is conducted from the tank to the burner by means of a pipe
so constructed at its mouth, for some of the contemplated purposes that it passes down
the centre of a steam pipe forming the core of same and the steam pipe in its turn is
surrounded by an air jacket communicating with air pumps by means of which the air
may be forced if required. The mixture of air fuel, and steam in proper proportions
gives perfect combustion and a most intense heat.
In order to illustrate how our invention may be conveniently carried into effect we
will further describe same with reference to the accompanying drawings.
Figure 1 is a longitudinal and Figure 2 is a transverse vertical section of a steam
boiler furnace for burning liquid fuel constructed according to one modification of our
invention.
A is the combustion chamber, B is the dome lining of fireproof material inserted in
the fire tube of an ordinary boiler as shewn, CC are the spray burners which may be
such apparatus as those described in the specification of a Patent granted to Carl Adolf
Sahlström the 19 November 1886 No. 15076 and these burners are fixed in such
manner that the flame impinges upon fire clay balls or pieces of fire brick D with
which the dome lining B is partly filled and when fire brick balls are used as shewn in
the drawing they are preferably formed with an aperture in such so as to expose
as large a surface as possible to the action of the flame. EE are openings or
passages in the dome lining B to allow the heat to pass from the combustion
chamber A and to act upon the fire tube F of the boiler; G G are the steam pipes
below the fire clay balls D for superheating the steam to supply the burners Cand
HH are tubes for heating and conveying the hot air to the burners C. These
steam pipes G and air pipes H may be arranged in the form of a coil or coils so as
to give them a circuitous course before arriving at the burners in order to obtain a
greater heating surface for the steam and air. It is not absolutely necessary in this
case to force the air through the air jacket of the burner. When this method of
firing is used in steam ships where it is necessary to economise the fresh water
in the boilers the fuel can be forced into the burners by means of compressed air
or steam or preferably in the following manner. The fuel is contained in one or
more tanks constructed in the same manner as the boilers. Into the upper portion
of the tanks, compressed air or preferably steam is forced by which means the fuel is
driven through the burner at a high velocity. The interior of the fuel pipe of the
burner is or may be deeply rifled so as to give a rotary motion to the stream of fuel
and spread it on its exit at the mouth of the burner.
The pipe conveying the compressed air or steain and which immediately surrounds
and encloses the oil pipe may also be rifled the volutes being in the same direction or
in a contrary direction to those of the fuel pipe.
Or the same effect of spreading the fuel into fine spray on its issuing from the
burner may be produced by a pair of fine platinum or other suitable metal membranes
between which the fuel either with or without steam or air is forced. Or again
a rotating mouth piece may be used to produce the required effect.
Figure 3 is a vertical section, and Figure 4 is a horizontal section through the
line X Y of Figure 3 of so much of a cupola furnace for melting metal such as iron
constructed according to our invention as will be necessary to explain same, and
Figure 5 is a diagram view shewing the arrangement of air flues. The main structure
is composed of brick as customary preferably cased with iron. A is the melting
chamber formed in the interior of the main structure, the lower portion A' of this
chamber is widened to allow, for the circulation of the flame therein and forms the
combustion chamber. CC are the spray burners such as those before referred to and

page_text: arranged radially three being shewn as best seen at Figure 5. J is an annular air
belt surrounding the cupola and this air belt may be otherwise constructed or
arranged from this belt there are air passages H in the thickness of the brickwork,
the direction and arrangement of which passages are shewn at Figure 5.
:
These passages lead as shewn at Figure 3 into the interior of the cupola and also
by passages H' lead to and supply the spray burners with heated air. The material
(iron ore for example) to be melted is inserted at the top of the cupola, the spray
burners Care put into action and hot air'and steam being simultaneously admitted by
the air pipes H' and steam pipes G the material is melted and may be drawn off
through the widened out base A¹ at the bottom of the cupola.
Figure 6 shews in sectional elevation a smelting furnace for burning liquid fuel
constructed according to our invention and suitable for smelting brass or copper.
In this case the fire clay crucible B is for containing the metal to be melted and
this arrangement is particularly applicable when small quantities of metal are to be
treated or when it is advisable to keep the metal from direct contact with the flame.
The main structure is composed of brick and preferably cased with iron as in the
previous arrangement.
The furnace proper is constructed of fire brick with iron casing and is formed with
an enlarged chamber A¹ at its lower part, B is the crucible placed immediately
somewhat above the enlarged chamber A¹.
The flue L leads off from around the crucible and the products of combustion are
caused to pass through a flue chamber L'in which metal may be piled for preliminary
heating and wherein there also fitted air heating chambers H and steam heating
coils G. L2 is the passage to the main flue and chimney; K is a sight hole; M is a
shutter for closing the flue. The burners not shewn in this drawing communicate
with the chamber A¹ and these burners are arranged at a tangent to the side of the
chamber and with a downward inclination in such manner that the frame comes into
contact first with the fireclay or other filling material or the side of the furnace before
acting on the crucible containing the metal. Sight holes are provided by which it
may be seen that the materials introduced are properly regulated in proportion to one
another.
Figure 7 shews in vertical section a portable or movable retort furnace arranged
and constructed according to our invention for burning liquid fuel.
In this arrange-
ment the retort is divided into two parts, P being the upper part and N the lower
part, the latter being preferably made of hemispherical form and may be used as the
receptacle for a crucible containing the metals to be melted or may be used as a
crucible itself. If used as a receptacle for a crucible the burner or burners are fixed
in the lower part in a similar manner to that before specified and in this case the
upper portion P of the apparatus is made so that it can be lifted off or put upon the
above mentioned lower portion N.
If used as a crucible itself as here shewn the burner or burners C C are preferably
fixed in the top or upper portion P. This top compartment P is somewhat cone-
shaped and preferably contains the tubular coils G and H or other means used for
utilizing the spent gases in heating the steam air and oil for supplying to the burners
as already mentioned. J is the air jacket communicating with the coils H and
supplying hot air to the burners as before described.
Means may be provided for attaching a crane or some equivalent so that the retort
can be carried to any required place tilted and otherwise manipulated.
In some cases and especially where an interior crucible is employed the space
between the lining and the chamber may be filled with balls of fireclay or other
suitable material through the interstices of which the flame passes.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :
I. In boiler furnaces for burning liquid fuel, the combination and arrangement with
the fire tube F and the spray burners, of the dome lining B combustion chamber A

page_text: steam and air heating tubes G and H together with the fire brick balls Dagainst which
the flame impinges the burners being inclined for that purpose all substantially as
and for the purposes set forth with reference to Figures 1 and 2 of the accompanying
drawings.
2. In cupola furnaces for burning liquid fuel the combination with the spray
burners, of the lower widened portion thereof A¹, air belt J, air passages H and H¹
and steam pipes G and parts connected therewith all substantially as and for
the purposes set forth with reference to Figures 3, 4 and 5 of the accompanying
drawings.
3. In brass and copper crucible smelting furnaces for burning liquid fuel, the com-
bination with the spray burners arranged tangentially and with a downward inclination
of the chamber A¹ and crucible B substantially as set forth with reference to Figure 6
of the accompanying drawings.
4. In brass and copper crucible smelting furnaces for burning liquid fuel the
combination with the spray burners arranged tangentially and with a downward
inclination of the enlarged chamber A!, crucible B, flue L, flue chamber L' and air and
steam heating apparatus G H situated therein and the parts connected therewith all
substantially as herein before described and illustrated with reference to Figure 6 of
the accompanying drawings.
5. In portable retort furnaces for burning liquid fuel the combination with the
inclined spray burners C of the divided retort composed of the upper conical part P
and the lower hemispherical part N the tubular heating coils G and H and the air
jacket J and parts connected therewith all substantially as and for the purposes herein
set forth with reference to Figure 7 of the accompanying drawings.
6. The general construction, combination and arrangement of parts composing our
liquid fuel furnaces all substantially as and for the purposes set forth.
Boted the ■ ou a
Ina LOCA
Doted the
BREWER & SON,
33, Chancery Lane, London, Agents for the Applicants.