Improved Means for Preventing the Formation of Smoke in Steam Boiler and other Furnaces, and Increasing the Temperature of the Flues distant from the Firegrate or Furnace.
Year: 1890

page_text: Date of Application, 8th May, 1890
Complete Specification Left, 25th Feb., 1891-Accepted, 8th May, 1891
PROVISIONAL SPECIFICATION.
Improved Means for Preventing the Formation of Smoke in Steam
Boiler and other Furnaces, and Increasing the Temperature of
the Flues distant from the Firegrate or Furnace.
THOMAS GIRDWOOD HARDIE Civil Engineer 36 Vernon Street Church Lane
Harperhay Manchester do hereby declare the nature of this invention to be as
follows:-
First. The firebars are made as thin as possible so as to give increased airspace,
and are perforated so as to increase circulation of the air, and keep them cool.
Second. A hollow bridge is formed of perforated cast-iron, fireclay or other
material in lieu of a solid one so as to admit of air to the furnace and flues beyond,
and to mix air with the flame and gases of combustion as they pass over it.
Third. Perforated pipes or flues, admitting air from without are laid in the tubes
and flues regulated by valves automatically or by hand. And small perforated
pipes are placed alongside of them wherein gas, petroleum, fine coal dust, or other
ensily ignited substance is drawn or forced into the flues to increase their
temperature, and assist combustion, and give added boiler power.
1000
T. G. HARDIE.
COMPLETE SPECIFICATION.
Improved Means for Preventing the Formation of Smoke in Steam
Boiler and other Furnaces, and Increasing the Temperature of
the Flues distant from the Firegrate or Furnace.
I THOMAS GIRDWOOD HARDIE residing at 36 Vernon Street Church Lane
Harperhay Manchester, in the County of Lancaster Civil 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 :-
To diffuse the air entering the furnace in, and amongst the glowing fuel on the
hearth, so that the oxygen may have an opportunity of coming in contact with, or
within the range of chemical affinity with the carbon of the fuel and equivalently
combine and form carbonic-acid the only product of complete combustion of
carbonaceous matter.
The means adopted to effect that object are as follows.
Firstly. The firebars are made as thin as consistant with durability, so as to
admit more air into, and be better diffused through the fuel, and the diffusion of
air or oxygen is greatly assisted by the admission of air into and amongst the fuel
on the hearth of furnace, by perforated pipes, tubes or boxes, regulated by valves
passing air into and amongst the burning fuel from the front of boiler.
Secondly. Instead, of the usual solid brick bridge at the end of firegrate a
hollow one is formed of cast-iron or other material perforated with numerous small
holes, lined with fire brick on the furnace side, and supplied with air from the front,
by the pipe G through the ashpit of furnace A. This pipe or flue is extended to
the end of the fire-tube D, in the case of Cornish, or Lancashire boilers where the
fire or furnace is placed within the tube or tubes. The object of the perforated air
pipes G is to diffuse oxygen if required to continue the combustion of any uncon-
sumed fuel that may have passed from the furnace C over the bridge B into the
tube D and flues beyond.
Thirdly. Small perforated pipes H charged with gas from the street mains, or
D
1

page_text: other gas, or gases mixed, regulated by taps, cocks or valve--or they may be
charged with petroleum from a cistern or barrel elevated to give the pressure
required to discharge it through the small holes in the form of spray, regulated by
aps, or valves or fine coal-dust may be discharged or drawn in by the indraught
of the furnace Blues, from a hopper, or cistern placed or fixed on the end of the
boiler seating, or where convenient also regulated by tap or valve.
Fourthly. These are the means proposed to be adopted, and the substances to be
used by preference, to prevent, or lessen the formation of smoke, and to increase
and regulate the temperature in the flues distant from the furnace or firegrate. But
1 do not confine myself exclusively to them-or any particular substance, or mode,
or means of using them. What I claim as new, is an improved means of preventing
the formation of smoke in steam boiler, and other furnaces, is a more complete and
minute diffusion of the air in and amongst the fuel on the hearth when in a glowing
state_and_supplying air by perforated pipes into the flues hitherto devoid, yet
requiring it and in keeping up, or increasing the temperature of the furince,
and flues distant from the furnace or firegrate by burning gas-petroleum-ur fine
coal-dust or other substances therein.
Having now particularly de-cribed, and ascertained the nature of my said
invention, and the manner it is to be performed, 1 declare that what I claim as
new, and original is preventing or lessening the formation of smoke from steam
boiler, and other furnaces, and in increasing or keeping up the temperature of the
Blues distant from the furnace or firegrate, and which as far as I know, has not been
hitherto tried, or even suggested, is a more complete and minute diffusion of air or
oxygen into, through, and amongst the fuel than by the grate-bar spaces alone,
whether by natural or mechanical draught, so that each atom of carbon contained
in the fuel, may have an opportunity of receiving, and combining with its equivalent
of oxygen required for complete union or combustion.
1st. By making the firebars of the furnace C as thin as consistant with durability,
and by placing or fixing thereon, perforated boxes, or pipes, receiving air from the
front of the boiler, the quantity admitted being regulated by valves &c.
2nd. A particular form of hollow bridge or partition B at the end of the furnace,
or fireplace, in lieu of the usual solid one, so as to diffuse air at that part in and
amongst the flame and gases that may contain carbon, or hydro-carbon that have
not entered into combustion for want of their equivalent of oxygen.
3rd. Perforated pipes G of fire clay, or iron, or other material to convey and
diffuse air through the perforations along the tubes D, and bottom of the boiler E,
and side flues leading to the chimney and to supply the air required for the com-
bustion of the fuel used to heat the flues, and parts between the furnace and the
chimney.
4th. Increasing the temperature of the flues C. D. E & F by the combustion or
burning the following or other inflamable substances therein viz. gas from the street
mains, or other gas or mixed gases or petroleum-or fiue coal-lust-or other
substances conveyed into these flues and parts through small perforated pipes H
lying alongside of the perforated air pipes C, both the quantity of air and com-
bustable matter admitted into the flues is regulated by cocks, taps, or valves.
Dated Sixteenth day of February Eighteen hundred and ninety-one.
THOMAS GIRDWOOD HARDIE.