Improvements in Effecting the Combustion of Fuel and Prevention of Smoke in Steam Boilers, also applicable for Domestic Fire Grates.
Year: 1890

page_text: Date of Application, 8th Sept., 1:90
Complete Specification Left, 6th June, 1891-Accepted, 1st Aug., 1891
PROVISIONAL SPECIFICATION.
Improvements in Effecting the Combustion of Fuel and Prevention
of Smoke in Steam Boilers, also applicable for Domestic Fire
Grates.
I, SAMUEL ALBERT JOHNSON of 3 Montagu Place in the Parish of Poplar,
London, E. Marine Engineer, do hereby declare the nature of this invention to be
as follows:-
By my invention I propose to effectually secure a more thorough and practically
perfect consumption of smoke and other products of combustion in the furnaces of
marine or other boilers than heretofore, which are usually allowed to escape; while
at the same time it effects a considerable economy in the consumption of fuel, as
perfect combustion is ensured. It is likewise applicable to household fire grates
or stoves or like purposes.
way
In the case of marine or land boilers of the general type or class as now in
ordinary use, or of any other later novel type, I do not intend in any material
to alter their constructional arrangement, but propose to provide and fit as in
addition thereto at or about and above the rear end of the furnace bridge a plate of
suitable material, proportion or area, which may be either plain or perforated, and
securely place and fix same in position at a suitable angle as from or about the
said furnace bridge in manner indicated (but in some cases I may so arrange and
dispose the said plate as to be movable or hinged so as to vary or alter the angle
of same should it in some cases be found more desirable); on the upper surface or
area of the said angular or deflecting plate I place a series of asbestos bulls or
blocks, or of a combination of asbestos with other suitable material or of fire clay
or of other like or suitable material capable of withstanding intense heat and of
retaining same; and as in the case of tubular boilers I so arrange that at some or
a convenient or suitable number of the lower set of boiler tubes, I fit thereto at
each of their ends with a short length of tube slightly lesser in diameter at one end
of each, so as to fit therein, within the mouth of each tube, at the fire bridge end
and within the lower portion of the combustion chamber, and just above the inclined
or angularly fixed plate previously referred to. The projecting or outward ends of
the short lengths of tubes, (whose open portions are inserted in the main tubes,)
within the said combustion chamber would have their outer ends closed and be
coated or covered over in their outward or projecting parts with either fire clay,
asbestos or mixture thereof or of any suitable fire proof material or combination of
same, which covering or coating as well as the length of the projecting tube itself
would be perforated throughout. I also fit and provide to each of the lower
corresponding tubes as at the smoke box or furnace end a further series of short
lengths of tubes of smaller diameter so as to fit within the mouth or end of each tube
to which they are applied and to project outwardly also, but open at their ends to the
atmosphere, so that a continuous and fresh atmospheric current would pass into the
short lengths or open tube connections into the lower tubes and the said induced
atmospheric current heated in its passage would readily and freely escape through
the perforated openings so fitted and which protrude within the combustion
chamber, and the heated fresh air would freely impinge upon and around also mix
with the gases or products and so combine with and materially aid in the combustion
which would be further secured by the smoke or other products having to meet the
great heat stored or retained in the balls or blocks of asbestos or other fire proof
material upon the angularly disposed plate.
And it will be found in practice that in boilers fitted as in accordance with my
invention that the smoke and heated gases would in their passage over the fire

page_text: bridge and in traversing over the fire proof asbestos balls or blocks (or of other
suitable material) would be so arrested that with the continuous currents of induced
fresh air, would so rapidly combine and decompose, that all wasto gasos and smoke
would be entirely consumed.
For household grates or stoves | may propose to employ vertical pipes or tubes 5
closed at their upper ends and perforated all round same and fitted and fixed at
their lower ends in a plate which covers the bottom of the grate, the said pipes or
tubes being left open to the atmosphere at their bottom or lower ends.
Dated this 8th day of September 1890.
S. A. JOHNSON.
COMPLETE SPECIFICATION.
Improvements in Effecting the Combustion of Fuel and Prevention
of Smoke in Steam Boilers, also applicable for Domestic Fire
Grates.
I, SAMOEL ALBERT JOHNSON of 3 Montagu Place, in the Parish of Poplar,
London, E. Marine 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 and accompanying drawings :-
By my invention I propose to effectually obtain a more thorough and practically
perfect consumption of smoke and other products of combustion in the furnaces of
inarine or other boilers than heretofore; and at the same time secure a very
considerable economy in the consumption of fuel. It is likewise applicable to
household fire grates or stoves or like purposes.
In the case of marine or land boilers of the ordinary type or class in general use,
or of any other later type or class of multitubular boiler, it is unnecessary by my
method or plan to materially alter their constructional arrangements, but in a very
simple mannor propose to provide and fit as in addition thereto, at or about and
above the rear end of the furnace bridge, a plate of suitable material, proportion or
area, which may be either plain or perforated, and securely place and fix same in
position at a suitable angle from or about the said furnace bridge, and I may prefer
to so arrange and dispose same, in some cases, as to be movable or hinged, that the
incline or angle given to the said plate may be varied or altered, as may be found
most advantageous in practice; and on the upper surface or area of the said
angularly disposed or inclined plate, I place a series of asbestos balls or blocks, or
a combination of same mixed with fire clay or other suitable material capable of
retaining great heat.
In the case of multitubular boilers I so arrange that some or a couvenient or
suitable mumber of the lower set of tubes are fitted at each of their ends with a
short length of tube slightly lesser in diameter at their inner portions so as to fil
and take within the mouth of two or more or several of the lower set of boiler
tubes. At the combustion chamber end and just above the inclined or angularly
fixed plate, upon which the asbestos or fire clay blocks are placed, so as to rest in
position thereon, the projecting ends of the said short lengths of tubes having their
open or inner portions inserted within the several lower innin tube ends and their
outer or projecting ends closed; the entire projecting outer surfaces of samo (within
the combustion chamber) are coated or covered with fire clay, asbestos or other
suitable mixture thereof or of fire proof kind and the said tubes and closed ends are
perforated throughout and around their projecting parts. To each end of the lower
corresponding boiler tubes at the smoke box end a further series of short lengths of
tubes are inserted and fitted within the mouth of each of the several boiler tube
ends, corresponding to those somewhat similarly shaped and fitted at the combustion
chamber end; and they likewise project outwardly, but in this instance toward and
into the stoke hole, their projecting ends being left open to the atmosphere, so that
a continuous and fresh atmospheric current may be and is induced to enter therein,

page_text: and in its passage through the main tube lengths, is led and diverted toward and
into the combustion chamber, arriving there in a very highly heated state. The
perforated openings around the projecting closed tube ends aid to the free
distribution of the highly heated air direct into the combustion chamber and thus
intermingly with the gaseous products of combustion evolved therein and freely
combining therewith, thereby instantly aiding toward the results desired which is
again further and finally secured by the smoke or other gaseous products having to
meet in their passage with the intense heat stored or retained in the luminous and
incandescent state of the asbestos or fire clay blocks or balls in position as before
referred to, whereby the entire products of combustion are instantly caused to burst
into flame; and as will be found in practice that the entire heating surface of the
boiler will derive the full benefit of the heat evolved from the more perfect
combustion of the fuel products as generated and consequently the entire
consumption of smoke will be thoroughly effected.
In order to regulate the heated gases in their passage ns toward the uptake, a
baffle plate is provided, pivotted or hinged at its lower part in the sinoke box, so
that they may be checked or arrested whenever desired and caused to further
impinge on the front of the boiler; the said baffle plate is adjusted by means of a
handle projecting into the stoke hole from where it is worked.
Provision is likewise made so that the admission of air to the projecting open
ends of the short lengths of tube (connected to the main tubes) may be wholly or
partially closed by an adjustable or regulating cover plate. If an excess of air to
that which would be ordinarily induced should at any time be needed I further
propose to provide and fix suitable nozzles in position, so that a jet or jets
of steam may be led into the open mouth of the projecting tube ends and capable
of being regulated at will.
In the accompanying drawings I have shewn at Sheet 1, Figure 1, a longitudinal
section of an ordinary type of multitubular marine boiler. Figure 2, is a view
partly in cross section and 'partly in elevation (front view) of same, wherein the
principle of my invention will be more readily understood and explained by reference
to the following letters, which refer to like or corresponding parts.
At or about the rear end of the furnace bridge it will be seen that a plate A, of
suitable area and proportion is fitted in position at a slight incline and hinged at its
lower end, so that the angle of same may be regulated or varied by means of a
lever arm B, and connection C, and rod D, acting upon same and worked from the
stoke hole end by the handle E. This angular plate A, is so formed as to receive
on its upper surface a series of asbestos balls or blocks F, or a combination of
asbestos and fire clay or other like or suitable material capable of retaining the
greatest amount of heat given out from the furnace. In the case of multitubular
boilers a certain suitable number of the lower set of boiler tubes as shewn at G, G,
are employed and a short length of tube connections H. H, of slightly lesser
diameter than the tubes themselves are fitted within the mouth of each of the
said lower tubes, just above the inclined or angular adjustable plate A, at the
combustion chamber end. These short tube connections H, H, would have their
outer ends closed, and their entire outward projecting parts coated or cased over
either with fire clay, asbestos or a compound of same or of other suitable fire
resisting material, and the entire projecting portion and closed ends thereof would
be perforated throughout. Each of the ends of the lower corresponding tubes at
the smoke box end would likewise have short tube connections K, K, inserted
within the mouths of same and their ends projecting outwardly under the smoke box
door into the stoke hole, but in this case their projecting portions or ends are left
open to the atmosphere, so that a continually fresh current of air is permitted to
enter therein and to pass into each of the lower main tubes directly toward the
combustion chamber. The said induced atmospheric currents will consequently
become highly heated in their passage through the said tubes and then escaping
freely through the perforated openings formed around the short projecting tube, and
in turn circulate and impinge upon the entire gaseous products and readily combining

page_text: therewith and at the same time the smoke or other products having to meet the
great heat stored or retained by the entire area of contents of the luminous
incandescent balls or blocks of asbestos or other materials, will likewise aid to most
effectively cause the entire unconsumed products to burst into flaine.
M, is a balle plate pivotted or hinged at its lower part within the sinoke box,
which is adjusted or regulated by means of a rod jointed to the said baffle plate and
hand connection N. O, is an adjustable cover plate connected to the arms P,
which enables it to be worked in a parallel direction, for regulating the admission
of air to the projecting open ends of the short tube connections K, K.
n
Figure 3, Sheet 2, exhibits a longitudinal section of an ordinary land or Cornish
boiler, wherein I have shewn my principle, but in a somewhat different manner, to
suit the particular purpose; in which R, is a horizontal tube inserted through the
ash pit and passing through the fire bridge, and the end or extremity of same R', is
closed, but the other end R2, is permitted to slightly project into the stoke hole and
is open to the atmosphere.
The end or extremity R', (with closed end) is pierced with holes to permit of the
atmospheric air readily passing through and around. Within the length of the said
tube R, a rod S is employed and works by means of the handle S'. This rod hus
at its end a lever connection or connections T, which work upon a pivot T'. U, is
a baffle plate having perforations therein and upon the face of which asbestos, fire
clay or other suitable material rests and the inrush of atmospheric air from the
perforated end of the tube R', is led to or passes through the highly heated blocks
of asbestos or fire clay for the particular purpose of consuming the smoke in manuer
previously detailed. V, is a bridge behind the fire bridge and W is a suspended
plate hinged to the baffle U, both of which prevent the air escaping into the flue,
as all air passing through the perforated openings of the tube end It, is intended to
upwards through the perforated portions of the plate U, which is raised or
lowered to any angle by means of the rod S, and lever connections referred to.
Figure 4 (Sheet 2) also shews that the principle of my invention can easily be
applied to the locomotive type of boiler wherein it will be seen that in addition
thereto have shewn that a certain number of tubes inay at one end be slightly
prolonged, as at the figures X-Y, and perforated around with the ends closed
(as in the combustion chamber end) the other extremities X, Y, are led and
connected to a tube Z, and are open to the air. Provision is in this case shewn
where connection is made from the steam dome of the boiler and the pipe
connection Z, communicates with nozzles Z, so that steam may be admitted into
and through the tubes X, Y, at their openings X and Y, and so induce further
atmospheric current into the combustion chamber whenever desired.
In the case of domestic fire grates as in accordance with my invention I
propose to insert a short length of tube within the fuel space toward the back
of the grate and having at the upper part thereof a further short length
connected to or tapped into the sides of the said vertical tube at about right
angles to the same, and closed at both ends forming as it were a T piece. The
upright length of tube would be secured at about its lower part toward the base
of the grate, and the end or bottom of same left quite open for the admission
of air, and the entire upper portion as well as the short horizontal length
T connections would be perforated throughout so that a perfectly free and
continuous upward current of rarified air would be freely distributed and intermingle
with the smoke and other resultants from the fuel-and will not only aid to the
more perfect combustion of same but entirely prevent and annihilate the smoke.
The outer portions of the said hollow T piece would have rings or covering of
asbestos, fire clay or other suitable unconsumable material placed thereon leaving
the perforations or air passages around same open, as in similar manner to that
described and illustrated for use in steam boilers.
I would however wish it to be understood that by the principle 1 propose of
inducing and distributing the circulation of air to the fuel and resultants in manner
referred to for domestic purposes, that the appliance as in manuer just referred to

page_text: would in some cases, have to be differently disposed and arranged to suit the
particular class of fire grate to which it would have to be adapted.
Having now particularly described the nature of my invention and in what
manner the same is to be performed I declare that what I claim is :-
The means or method for the prevention of smoke and in the economy of fuel by
the admission of atmospheric air in a rarefied state within the combustion chambers
and flues and by the employment of asbestos, fire clay, or other equivalent in like
manner substantially as herein set forth illustrated and described for the specific
and particular object and purpose set forth.
Dated this 6th day of June 1891.