IMPROVEMENTS IN FURNACES FOR BURNING POWDERED, LIQUID OR GASEOUS FUEL
Year: 1884

page_text: I THOMAS RUSSELL CRAMPTON of 4 Victoria Street in the city of Westminster
Civil Engineer do hereby declare the nature of my invention for "IMPROVEMENTS
IN FURNACES FOR BURNING POWDERED, LIQUID OR GASEOUS FUEL," to be as
follows:-
Heretofore in furnaces used for melting or making steel and also in furnaces for
heating steam boilers and which are to be heated by the combustion of powdered
fuel and air it has before been proposed to construct the roofs or tops and the
sides as well as the bottom of the furnace or combustion chamber of fire brick or
refractory material. The object of my invention is mainly to suppress the use of
such material in the construction of the sides and top of such furnaces.
I form the bottom of the furnace of a bed or bath of sand or other suitable
material either surrounded by a water casing or not. In this bath liquid slag is
formed when the furnace is in operation.
The sides of the furnace and the roof or the roof only I form of a water casing
which forms part of a steam boiler-the necessary apertures for working the
furnace and injecting the fuel and air are made preferably through the water casing
and the streams of fuel and air are so directed into the furnace as to ensure, as
perfectly as may be, that complete combustion shall take place immediately upon
and over the whole surface of the slag bath, and thereby cause as much as possible
of the heat to pass into the bath and avoid any combustion taking place
immediately under or near the surface of the boiler.
If steel has to be melted or made the materials are inserted into the liquid slag
bath or on to the sand projecting out all round the bath in which case when melted
they would run beneath the slag—the intense heat passing from the sheet of flame
into the slag and through the slag to the steel keeps it to the temperature desired.
In boilers for generating steam without melting steel it is not necessary in all
cases to form the bottom of refractory material the bottom of the chamber might
be a water casing which would chill the slag that came in contact with it and the
slag would then accumulate as a solid to a certain thickness over the bottom
whilst above this there would be a layer of melted slag when the furnace was in
operation.

page_text: In furnaces constructed as herein before described, the boiler may be constructed
independently of the bath portion and so arranged that the bath portion may be
removed from underneath the boiler portion for repairs or otherwise, and the
bottom portion may be made to revolve like an ordinary inclined revolving
puddling furnace,
The layer or sheet of flame formed immediately above the surface of the bath of
molten slag might be obtained by the combustion of oil or gas in place of with
powdered fuel.
It will be seen that if an ordinary locomotive engine is to be used for making or
melting steel it will be only necessary to form on the bottom of the fire box a bath
of sand on which the steel is to be melted and to blow the air and fuel on to
such bath. The heat generated and not taken up by the steel will pass into the
boiler.

page_text: I, THOMAS RUSSELL CRAMPTON of 4 Victoria Street in the City of Westminster
Civil Engineer do hereby declare the nature of my invention for "IMPROVEMENTS
IN FURNACES FOR BURNING POWDERED, LIQUID OR GASEOUS FUEL" and in what
manner the same is to be performed to be particularly described and ascertained
in and by the following statement:—
Heretofore in furnaces used for melting or making steel and also in furnaces for
heating steam boilers and which are to be heated by the combustion of powdered
fuel and air it has before been proposed to construct the roofs or tops and the sides
as well as the bottom of the furnace or combustion chamber of fire brick or
refractory material. The object of my invention is mainly to suppress as much as
possible the use of such material in the construction of the sides and top of such
furnaces.
I form the bottom of the furnace of a bed or bath of sand or other suitable
material either surrounded by a water casing or not. In this bath liquid slag is
continuously formed when the furnace is in operation the surplus being tapped out.
The sides or part of the sides of the furnace and the roof or the roof only I form
of a water casing which forms part of a steam or other boiler-the necessary
apertures for working the furnace and injecting the fuel and air and for the exit of
the gases are made preferably through the water casing and the streams of fuel
and air in a mixed state are so directed into the furnace as to ensure as perfectly
as may be that complete combustion shall evenly take place immediately upon or
over the whole bottom surface of the melted slag bath and thereby cause as much
as possible of the heat to pass into the bath and prevent any direct combustion of
the solid particles of fuel taking place immediately in contact with the other
surfaces of the furnace.
If steel has to be melted or made the materials are inserted into the liquid slag
bath or on to the sand projecting out all around the bath in which case when
melted they would run beneath the slag in the ordinary manner the intense heat
passing from the combustion of fuel formed immediately over the slag into the
slag and through it to the steel heating the steel to the temperature desired. The
bath for holding the slag is made of sand or other suitable material in the ordinary
way. Other metals than steel may be similarly melted or heated.
In boilers for generating steam or heating water without melting steel or other
metal it is not necessary in all cases to form the bottom of refractory material as
described the bottom of the chamber might be a water casing covered with slag.
In this case when the furnace is in operation the slag in contact with the casing
would be kept chilled and would remain as a solid to a certain thickness over the
bottom whilst above this there would be a layer of melted slag.
In furnaces constructed as herein before described the boiler portion may be
constructed independently of the bath portion and so arranged that the bath
portion may be removed from underneath the boiler portion for repairs or otherwise―
or the bath portion might be made to revolve like an ordinary revolving. steel
melting or puddling furnace.

page_text: It will be seen that if an ordinary locomotive form of boiler is to be used for
making or melting steel it will be only necessary to form on the bottom of the fire box
a bath of sand on which the steel is to be melted and line as much of the sides with
refractory material as desired and to blow the air and fuel on or near to such bath.
The heat generated and not taken up by the steel will pass into the boiler. If no
metal be melted then all the heat would pass into the boiler. A portion of the
heat might be utilized to heat the air for combustion or might be otherwise
utilized.
In some cases particularly where generation of steam only is required and where
the sides of the furnace are formed of a metal water casing the metal surfaces which
rise above the top surface of slag may have some of the slag splashed from time to
time up the metal sides. The slag would chill and adhere to these surfaces to a
certain thickness. One or more ledges or projections may be formed on the sides to
any convenient height above the bath on which projections solid slag (or materials
readily melted into slag) may be placed as required by throwing them in through
the ordinary working doors or through openings suitably arranged above the
projections. The materials on melting would run over the surfaces below and be
chilled into a solid upon them-melted slag might also be poured on to these ledges.
In some cases the bottom of the furnace may be made of fire bricks only the
bricks being carried vertically around the furnace for a convenient height the
boiler portion not protected by bricks resting on the brick bottom and forming
the top of the furnace.
The heating up of the furnace in the first instance is conducted in the way usual
with dust fuel furnaces the streams of air and powdered fuel are also directed into
these furnaces in the ordinary way.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is
1. The construction of furnaces with the bottom formed of a bed of sand slag
or other such like suitable material and with means of directing streams of air and
powdered fuel along or over the surface of such bed whilst the sides and top or
sides or top are of metal forming part of a steam or other boiler substantially as
described.
2.-The construction of furnaces heated by the combustion of powdered fuel and
air in such manner that steel or other metal may be melted or formed in the bed at
the bottom of the furnace whilst the upper part of the furnace is formed of a steam
or other boiler substantially as described.