Improvements in the Prevention or Combustion of Smoke in Furnaces.
Year: 1891

page_text: Date of Application, 13th May, 1891
Complete Specification Left, 31st Dec., 1891-Accepted, 6th Feb., 1892
PROVISIONAL SPECIFICATION.
Improvements in the Prevention or Combustion of Smoke
in Furnaces.
I, ALFRED RICHARD SENNETT, of Brentford, Middlesex, Civil Engineer, do
hereby declare the nature of this invention to be as follows :-
i
cause introduced air or a mixture of air and steam or other gases to impinge
on one or more deflecting plates in the furnace, or in connection therewith, so that
the currents are directed on to and distributed over the fire. The oxygen thus
introduced prevents the formation of smoke by effecting the complete combustion
of the carbon of the coal. The deflectors may if desired be made of some refractory
material and may be placed either above the centre or at the sides of the fire. It is
advisable to employ superheated steam to inject the air, and I sometimes also heat
the air before it is introduced. A portion of the hot gases the products of
combustion may be again introduced into the furnace with a fresh supply of
oxygen.
In the case of reverberatory furnaces and such as have no boiler above the fire,
I sometimes admit the injected air or mixtures by an opening in the cone of the
furnace, such opening being generally connected to the injecting apparatus by means
of a curved conduit in which case the curved side or sides of the conduit form the
deflector or deflectors.
Dated this 12th dow of Ma 1901
W. H. MUNNS,
Agent for Applicant.
COMPLETE SPECIFICATION (AMENDED).
Improvements in the Prevention or Combustion of Smoke
in Furnaces.
I, ALFRED RICHARD SENNETT of Brentford, Middlesex, 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:-
The object of my invention is the rendering of the combustion of fuel in steam
boiler and other furnaces more perfect, whereby the formation of smoke is prevented
and a greater amount of energy is obtained from a given weight of coal.
I cause introduced air or a mixture of air and steam to impinge on one or more
deflecting surfaces or plates in the furnace or in connection therewith, so that the
currents are directed on to and distributed over the surface of the fuel. The
oxygen thus introduced prevents the formation of smoke.
Fig. 3 shows in section an arrangement for carrying this out, the surface employed
being in this case a plate L, of such a shape and placed at such an angle with the
01.......מ

page_text: axis of direction of introduced air as to cause the latter to be distributed over the
surface of the fuel in the furnace P. T, represents the conduit conveying the current,
but a centrifugal fan, blowing engine, or any other suitable means of introducing
the current may be employed. The deflector or deflectors may be made of some
refractory material and may be placed either above the centre or at the sides of
the fire.
Fig. 11 shows in section an arrangement in which a block of refractory material
is employed, and which may be, as in this instance, very conveniently made in the
form of a complete, arch, the surface s, having the angle and shape requisite for
proper distribution. The air or mixture of air and steam or other gas or gases
may be introduced through an aperture, which I generally make in the form of a
crescent or ellipse, or several apertures may be made use of as shown at t, t, t, in
Fig. 10 which is a front view of furnace.
•
Fig. 12 shows in section an arrangement for the employment of two or more
deflecting plates L, L. In this case it will be seen that there are two crescent
shaped apertures ', ', inside the furnace.
In the case of reverberatory furnaces and such as have no boiler above the fire I
⚫ sometimes admit the injected air or mixture by an opening in the crown of the
furnace, such opening being generally connected to the injecting apparatus by
means of a curved conduit, in which case the curved or inclined sides of the conduit
form the deflector or deflectors. Fig. 13 shows in section such an arrangement.
The crown c, c, of the furnace is pierced by a suitably shaped orifice O, and the
source of the supply of fresh air or mixture is connected to this by a suitable
conduit,, which I generally construct of refractory material, and of a curved
form. The source of supply of the air or mixture is the apparatus shown at T, 6, B,
which is no part of my present invention.
For accelerating the speed of combustion of the fuel 1 cause the introduced air
or mixture to impinge upon the under surface of the fuel. By this means the
necessity for creating a pressure of air below the bars is obviated, and it is not
necessary therefore to employ either a closed stoke-hold or closed ash-pits.
Fig. 6
is a plan of the arrangement under fire bars shown in section in Fig. 3. I lead
the introduced air or mixture into a chamber M, from which it escapes by means of
an orifice, or orifices s, extending any required distance along or across the under
surface of the fuel. The edges or lips of this orifice or slit are composed of
movable sections, and, so that the width as a whole or any part may be adjusted
at will, whereby the quantity of air allowed to impinge upon any portion of the
surface of the fuel may be controlled. A similar system may be made use of on
the upper surface of the fuel when desirable. K is a guard to prevent ashes falling
into the slit when the apparatus is not at work. The trunk M may be provided
with more than one slits, as shown by dotted lines in Fig. 4, which shows the
arrangement of Fig. 3 as viewed from front of boiler, or several trunks may be
used in the same ash-pit. In the arrangement shown in transverse section in Fig. 5,
two trunks M, M, are employed, and the necessity for using the ash guard K, is
obviated by allowing the introduced current to issue from orifices or slits placed at
an angle, the proper direction for impingement being effected by the angle which
said orifice or orifices makes or make with the under surface of the fuel, or it may
be obtained by causing the two streams to mingle as shown by the arrows.
In injecting the air by means of steam it is advisable to superheat the steam
and I also prefer to heat the air or mixture before bringing it into contact with
the fuel.
Fig. 2 shows in longitudinal section a method of superheating. I employ a super-
heating bridge b, also shown in cross section at 2*. Steam from the boiler is led to
the hollow bridge b, and is preferably made to traverse a considerable distance
within the said bridge, so that it may come into contact with a large amount of
heating surface. This may be conveniently done by providing the bridge with a
series of tubes, or by inserting partitions as shown at p. Fig. 24. On emerging from
the said bridge the air or mixture is conveyed preferably in carefully covered pipes

page_text: to the injecting apparatus.. The bridge may be made of cast iron and have its-
interior face protected by brickwork or refractory material m.
In other cases such for example as when steam at very high pressure is
employed prefer to employ a superheater placed in the furnace or fire box of**
the boiler.
Fig. 9 shows such a superheater separately.
Fig. 94, is cross section of same.
The superheater is also shown in position at s', in the longitudinal section Fig. 8,.
and front view Fig. 7. The superheater consists of a receptacle preferably a.
casting having ducts so arranged that the steam passes backwards and forwards
from end to end, and for this purpose it is convenient to make the ducts in sets
of 2, 4, etc., so that the steam returns to the end whence it started. For example,.
the superheater shown in Fig. 9, has two pairs of ducts the part s', projects within.
the furnace while the part D is passed through the boiler front and may be secured
by the nut n. Steam is admitted to the superheater by a pipe connecting with one-
of the ducts say a Fig. 94, and is led away by a pipe connecting with another duct.
say.
I employ similar methods to heat the air. At Fig. 2, the superheating of the
steam and the heating of the air or mixture is effected by the use of two hollow-
bridges. The construction of the air heating bridge B is similar to that of the
steam beating bridge b. I prefer to make the passages of B less contracted than.
those of, as shown at Fig. 2.
Fig. 1 is front elevation of furnace.
In Figs. 1 and 2 the steam is led from the boiler to the steam bridge b, thence-
to the injector, whence the mingled volume of superheated steam and air passes to
the bridge B, and having traversed this latter passes to the hollow boiler front F,
whence it issues by the orifice O, and is caused to be properly distributed over the
fuel by the deflecting surfaces. In Figs. 7, and 8, the steam passes from the boiler-
by pipes p, p, p, to the superheaters s,, and having traversed the ducts of
these, it passes by pipes p³, p*, p to the injecting apparatus, thence by trunk M,.
which I prefer to make of oblong or elliptic section, to the bridge B. There it
bifurcates, one portion passing by the conduite, and the other by the conduit c², to.
the hollow boiler front F, whence it issues by orifice O, and is deflected on to and
distributed over the surface of the fire by means of the deflecting surface s. In
some case dispense with the deflecting plate and cause the current to impinge
upon the surface of the fuel direct from the said orifice.
L
Having now particularly described and ascertained the nature of my said inven--
tion and in what manner the same is to be performed, I declare that what I
claim is:
1. In a contrivance for the prevention of smoke and the more perfect combustion.
of fuel in furnaces the-system combination with the apparatus covered by Claims 6 and 7,
the method of distributing an introduced current or currents over the surface of the
fuel by causing the current, or currents, to impinge upon a deflecting surface or
surfaces substantially as described and shown in Figs. 3, 8, 11, 12 and 13.
2. In-a-contrivance for the prevention of smoke and the more perfect combustion
of fuel the system of introducing a current into the furnace through-a-cellular boiler
front-provided with an orifice or orifices so shaped and disposed as to distribute the
current or currents-over the surface of the fuel.
3. In a contrivance for the prevention of smoke and the more perfect combustion
of fuel in furnaces the system of using superheated steam for the purpose of injecting
a current to be distributed over the surface of the fuel.
2. The use of a hollow fire bridge such as bas described and illustrated in Figs. 2
and 2ª for the purpose specified.
4. In a contrivance covered by Claim-3 the hollow fire bridge b, for the
purpose of effecting such superheating substantially as described and shown in
nives and A

page_text: 3. The use of a superheater such as s¹ as described and illustrated in Figs. 7, 8, 9,
and 9, for the purpose specified.
5. In a contrivance covered by Claim 3 the superhenters' for the purpose-of
effecting such superheating, substantially as described-and-shown-in-Figs. 7, 2, 0,
and-9
6. In-a-contrivance for the prevention of smoke-und the more perfect-combustion
of fuel in furnaces, the system 4. The method of heating the air or other gases or
mingled volumes of steam and air or other gases, which are to be distributed on the
surface of the fuel, by passing the same through hollow fire bridge B substantially
as described and shown in Figs. 2, 2", and 8 for the purpose specified.
7.
In-a-contrivance-for-the-prevention of smoke and the more perfect-combus-
tion-of-fuel-in-furnaces, the system 5. The method of introducing a current or
currents to be distributed over the surface of the fuel by means of one or more
apertures in the crown of reverberatory and other furnaces substantially as described
and shown in Fig. 13 for the purpose specified.
8. In-a-contrivance for the prevention of smoke-and the more-perfect-combustion
of fuel in furnnees the system of obviating the necessity of employing a closed
stokehold-or-closed-ash pit by 6. The method of and apparatus for causing an
induced current to impinge ou the under surface of fuel in furnaces without a closed
stokehold or closed ashpit, substantially as described and shown in Figs. 3, 4, 5, and 6 for
the purpose specified.
0. In a contrivance 7. In apparatus covered by Claim 6 the aperture or
apertures s, which can be regulated so as to distribute the current on to any
desired part substantially as described and shown in Figs. 3, 4, 5, and 6.
Dated this 30th day of December 1891.
W. H. MUNNS,
Agent for Applicant.