Improved Apparatus for Injecting Liquid and Pulverised Fuel into Furnaces.
Year: 1899

page_text: Date of Application, 21st Nov., 1899-Accepted, 27th Jan., 1900
COMPLETE SPECIFICATION.
Improved Apparatus for Injecting Liquid and Pulverised Fuel
into Furnaces.
We, ERNEST ARMAND VETILLARD, Engineer to the Western of France Railway,
and EUGENE SCHERDING, Junior, Merchant, both of 22, Rue du Bouloi, Paris,
in the Republic of France, do hereby declare the nature of this invention, and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
This invention relates to certain improvements on our Patent No. 8589 of 1899
for "Improvements in apparatus for feeding liquid fuel into furnaces."
Our improved apparatus enables a stream of liquid fuel, and of pulverised fuel,
to be injected as may be desired, either simultaneously or separately, into a
furnace consuming solid fuel. This apparatus completes the installation described
in our former patent, in as much as it comprises an arrangement by means of
which pulverised fuel of any kind (the combustion of which is promoted by the
combination of the gaseous mixture) can be fed into the furnace simultaneously
with the said mixture.
The mechanism is so contrived that either the feeding of gasified liquid fuel
only may be interrupted or the feeding of both kinds of fuel at the same time.
in order that these improvements may be understood, we append to this descrip-
tion a drawing, the different figures of which are drawn to varied scales.
Figure 1 being a sectional plan, and Figure 2 a front view of a compound
injector for liquid and pulverised fuel, embodying one of the improvements.
Figure 3, a diagram of an installation in relation to a boiler and forming a
second improvement.
Figure 4, is a detail, in vertical section of the distributing box, constituting a
third improvement.
· Referring first to Figures 1 and 2, we will now describe the modification effected
in the "jet" apparatus.
The construction of the combined or compound injector, for liquid fuel and
pulverised fuel, shewn in Figures 1 and 2 is the same as that of the injector
represented in Figures 4 and 5 of the drawing annexed to the specification of the
principal patent, with the exception of the distinguishing features which we are
about to explain.
The difference is that the cone (c³) instead of opening directly into the atmos-
phere, for the purpose of taking up pure air, contains another cone, always
conical, indicated by (c10). Into the annular space left between (3) and (e),
the pipe (c) of an aspirator" opens. Steam passes into the latter through the
pipe (2), drawing the air through the orifice (c¹³), which is open to the atmos-
phere, and through the pipe connection (c14).
"
We would here remark that the suction jet or stream entering through (c¹²)
may either consist of compressed air or some other fluid under pressure, instead
of steam.
Connected with the central space of the cone (c¹0) is a pipe (c¹5) which com-

page_text: municates with the distributing box (X) and the funnel containing the pulverised
fuel.
The effect of the stream of steam and air entering the apparatus through the
annular space between the cones is that a current of air is drawn up through the
pipe (c), this current of air forming the vehicle for the pulverised fuel, the par-
ticles of which it carries in suspension, and which is thus injected into the
furnace simultaneously with the liquid fuel.
It should be observed that the pulverised fuel is in the axis of the injected
stream, and that the combustion is thus greatly promoted by the presence of the
gasified liquid fuel which surrounds it, so much indeed, that the combustion is
effected entirely without smoke.
1.
We would observe, further, that we are able, as has already been suggested
elsewhere, to inject into the furnace, simultaneously with the air and the fuel
an oxygenating or combustive agent of any kind, in a gasified, liquid, or solid
pulverised form in order to stimulate the combustion and render it more complete
in certain cases.
The stream of air carrying the particles of solid pulverised fuel in suspensión
and in certain cases the particles of the oxygenating agent, and which is drawn
in through the tube (15) is produced by the following arrangement.
The tube (c) extends to the bottom of a box (X) already mentioned (Figures 3
and 4) placed below the funnel (Y) (Figure 3) containing the pulverised fuel.
The funnel (Y) communicates with the box (X) by a pipe (y) which. penetrates
nearly half-way into the said box passing through the cover of the same and is
situated at the opposite end of the box, to that, to which the tube (a) of the
pipe (c), is connected.
An air-intake pipe (2) is attached to the cover of the box. and opens into, the
box near the tube (y). The opening from the pipe () to the box is contracted.at
(2) and is regulated if necessary by a valve. On the bottom of the box between
the openings (¹) and (e) is a transverse vertical partition (t) extending half-way
up the box.
It will be readily understood that the suction effected by the injector in the
tube (15), will draw pulverised fuel from the funnel (Y) and air through, the
pipe (z). Owing to the arrangement and height of the partition, the arrange-
ment and length of the tube (y), and the arrangement and form of the pipe (z)
the solid particles and air, which are drawn up are intimately blended and evenly
diffused, so that a stream of air containing particles of pulverised fuel in suspen-
sion, reaches the injector through the tube (c¹5). The elements of this stream
may be easily proportioned owing to the means indicated.
As regards the installation of the compound injector for liquid and pulverised
fuel in connection with a boiler furnace, it does not differ from that described
in the principal patent (Figures 1 and 2 in the latter) except in the following
respects which will be easily understood by reference to the accompanying draw-
ing (Figure 3).
The whole installation is the same as previously but there is in addition a
steam-intake (16) furnishing steam to the air and pulverised fuel "aspirator."
This steam-intake is independent of that for the injection of the liquid fuel so that
either the one or the other of these kinds of fuel may be injected separately or
both at the same time.
The distributing and mixing box (X) and the funnel (Y) for the pulverised fuel
may be placed in any way that is convenient.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what
we claim is:-
Firstly An injector, in accordance with the claims in our principal patent
in which the one or more "jet" apparatus, inject, besides the liquid fuel, pul-
verised fuel into the furnace, mixed with suitable quantities of combustive air,

page_text: (and if necessary of an oxygenating agent), so that the stream of pulverised fuel
is surrounded by the stream of gasified liquid fuel.
Secondly: In injectors as described in Claim 1, an apparatus with mixing
"jets," of which apparatus a first injector takes in the air which mixes with
steam; this mixture, having reached the opening of a second and conical injector,
drawing up, through a central pipe, the pulverised fuel and air, and the whole
of the fuel mixed and well diffused being projected into the furnace, passing
through a gasified mixture of liquid fuel, steam and air; this gasified mixture
being produced by a third injector, drawing up the liquid fuel, mixing it with
the steam and injecting it in the form of a cylindrical jet, whilst two conaxial
injectors convert this cylindrical jet into an annular jet, caught between a layer
of external air and the mixture of pulverised fuel and air entering through the
internal pipes, the result being that the pulverised and liquid fuel, the steam and
the air are thoroughly mixed and diffused.
Thirdly-In injectors according to the preceding claims, a distributing box
for the pulverised fuel inserted in the conduit between the reservoir for this fuel
and the "aspirator" in which the proportioning of the mixture of combustive
air and pulverised fuel is effected by the arrangement between the entrance orifice
of the fuel admission tube and the outlet tube for the stream of air which conveya
the pulverised fuel, of an air-intake pipe which can be regulated and of a parti-
tion or screen substantially as described in relation to Figure 4.
Fourthly-In injectors according to the preceding claims the arrangement in
combination with the reservoirs for the liquid fuel and the pulverised fuel, the funnel
and the distributing and mixing box for the pulverised fuel, of the necessary
arrangement of pipes and cocks in order to enable a mixture of liquid fuel, of
air, and steam and a mixture of pulverised fuel, air and steam to be thrown
into the furnace together or separately substantially as described.
Namb 1900
W. D. ROWLINGSON,
7, Quality Court, Chancery Lane, London, W.C., Agent for the Applicants.