Improvements in Steam Boilers or Generators.
Year: 1887

page_text: [Communicated from abroad by VICTOR COLLIAN, of Detroit, Michigan, United States
of America, Gentleman.]
Improvements in Steam Boilers or Generators.
I HENRY HARRIS LAKE, of the firm of Haseltine, Lake and Co., Patent Agents,
Southampton Buildings 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 following statement :-
This invention relates to steam generators, and has for its object to increase the
efficiency of such generators by applying an improved kind of furnace and an improved
mode of burning the fuel compared with those heretofore used for generating steam
for use as a motive power or otherwise.
The kind of furnace I apply in my improved steam generator is the one known as a
cupola furnace, wherein the combustion of the fuel is carried on by means of a hot air
blast.
As the efficiency of a steam generator is in proportion to the combustion of fuel, a
comparison of the respective amounts of fuel and heat obtained from the ordinary boiler
furnace and the cupola furnace will readily disclose the superiority of the latter.
-
In the former 1lb. of coal produces about 8 lbs. of steam of 5 atmospheres, at a
temperature of 153 degrees C. making the total amount of 8 x 153: 1224 degrees.
In the latter with 1 Ib. of coke I have melted as much as 13 lbs. of iron, which at
the melting temperature of 1200 degrees C. represents 13 x 1200:
16200 degrees.
This is a difference of 15000 degrees in favor of the cupola furnace as a direct result
of the superior combustion.
=
Again, in a boiler furnace under the best conditions of draught the amount of coal
that can be burned per hour on a square foot of grate does not exceed 120 lbs., while
in the hot blast cupola I have burned as much as 822 lbs. of fuel per square foot of
tuyere, per hour, which utilized for the production of steam would represent 6576 lbs.
of steam, per foot square of tuyere, as against 28 lbs. made by the Cornish boiler, or
960 lbs. by the best burning fuel locomotive per square foot of grate. These figures

page_text: are easily explained when it is considered that two things are essential to the proper
combustion of fuel viz. a sufficient supply of oxygen and a high temperature, and these
two must be in the most intimate combination. Now in the modern boiler furnace,
most of the time, only a small portion of the fuel on the grate is properly burned and
the rest is distillated, forming hydro-carbon gases which only help the generation of
steam by their temperature, or if partly inflained these gases are soon extinguished in
the complicated ducts and pipes of modern boilers, in which it is impossible to maintain
combustion.
In carrying out my invention I preferably combine a cupola furnace with a boiler
in such manner that none of the advantages of efficiency claimed for the cupola furnace
are lost, all as hereinafter shown and described.
In the accompanying drawings my improved steam generator is shown in vertical
central section, and the letters of reference indicate the following parts
A represents a solid bottom of any known or desired construction adapted for the
purpose desired, which can be dropped; it must be air tight and fire proof inside, lined
with brick, fire clay or sand. B is the cylindrical furnace chamber. C is the lower
section thereof lined with brick to near the height of the lower buyeres.
D is the boiler proper made of double metallic shell forming an annular water and
steam chamber D, containing the water to be evaporated, and extending from the
bottom of the furnace to the top of the furnace proper, where the steam is contained
in a drum preferably formed by enlarging the outside diameter of the boiler.
E is a metallic shell surrounding the lower portion of the whole, forming an outside
enclosing annular air chamber F; covering all the tuyeres; it is provided with an
inlet G, which is connected with a blower or fan (not shown) of any desired
construction, by means of which air is driven into the annular chamber.
Between the air chamber F and the inside of the furnace, there are several systems
and series of tuyeres T, distributing the blast in the furnace in such manner as to force
the blast to strike horizontally the vertical inside shell of the boiler, giving to the whole
of the vertical inside shell the maximum of efficiency of evaporation, as effectually as
the bottom of common boilers are heated on the top of the fire grate, making the whole
of this surface more than ten times as effective as the heating surface of the common
boiler.
The furnace is made air and water tight in such manner that when located in a
steam boat the fire could not be extinguished even if the boat were half full of water.
O is a slag hole which is closed by means of clay and sand, and is opened
occasionally to let the slag out, the ash of the fuel being made fusible by a small
addition to the fuel of a base such as lime.
S is an outlet steam pipe from the boiler to the steam engine.
His the fuel loading door, situated above the whole steam making apparatus and
above the steam dome.
Wood being put in at first at the bottom of the furnace it is lighted without the
use of the blast, by leaving all the tuyeres open. The coke or coal is thrown on
gradually until, being well ignited, it has attained the top of the higher tuyeres,
when blast is applied. The combustion is almost perfect, its produce being only
carbonic acid gas, which, by being an extinguisher prevents the upper strata of fuel
from burning, the combustion ceasing entirely about or 4 feet above the upper
tuyeres, so that there is no inflammable gas escaping and neither fire nor smoke
appears above the loading doors, it being as cool there as if there were no fire below.
According to the quantity of ashes contained in the fuel used a sufficient
quantity of a base, such as lime or fluor spar, is mixed with the fuel before loading,
in order to produce a liquid slag which can be drawn out when necessary.
K is a blast gate to regulate to pressure of the blast, and by so doing it also
regulates the production and pressure of steam, for, contrary to the old system of
making steam, which consists in increasing the quantity of fuel on the grate when
more steam is required, in my new furnace boiler the quantity of fuel is kept
constantly at the same height above the upper inyeres, the intensity of combustion
and the production of steam being entirely controlled by the quantity of the blast.

page_text: M is the blast meter on the air box to indicate the pressure of blast by which
the production of steam is controlled.
Jis the feed water pipe to furnish the water necessary to the boiler provided
with pumps and injectors (not shown).
I is the chimney or stack to admit the dranght of the furnace.
Other very important advantages of my steam generator over any other kind are
that the whole of the apparatus is entirely cold outside, and that the heat which escapes
and makes the care of the old system of boiler so tiresome and uncomfortable to the
stoker, especially on the inside of a boat, is all collected by the outside double
metallic shell surrounding the lower portion of the whole furnace. The stoking of
the furnace is done without the least inconvenience, there being no heat escaping at
the feed doors.
Having now particularly described and ascertained the nature of the said invention,
and in what manner the same is to be performed, as communicated to me by my foreign
Correspondent, I declare that what I claim is
First. In a steam generator, the combination of a cylindrical furnace open at the
top and closed at the bottom, a vertical annular boiler forming the furnace chamber,
and a system of tuyeres carrying an air blast through the sides of the boiler into the
furnace, substantially as described.
Second. In a steam generator, a furnace closed at the bottom and open at the top,
and provided with an air feeding system of tuyeres in the sides of the furnace,
substantially as described.
Third. In a steam generator, a furnace open at the top and closed at the bottom by
imperforate doors, and provided with an air feeding system of tuyeres in the sides and
a slag hole near the bottom, all substantially as described.
Fourth. In a steam generator, the combination of a cylindrical furnace open at the
top and closed at the bottom, a vertical annular boiler forming the sides of the said
furnace, a vertical extension of the said furnace above the top of the boiler, a fuel door
in the said extension, an air feeding system of tuyeres through the walls of the boiler
into the furnace, and an outside shell surrounding the boiler and forming an inclosed
air chamber therewith, all substantially as described.
Fifth. In a steam generator, the combination of the annular boiler D, the furnace B,
open at the top, and having the imperforate bottom A, the interior lining C, the slag
hole O, the tuyeres T, the air chamber F, the blast pipe G, the chimney I, and the
feed door H, all substantially as described.
HADELINE, LAKE & CO.,
45, Southampton Buildings, London,
Agents for the Applicant.